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Abstract Background Mounting evidence links glucose intolerance and diabetes as aspects of metabolic dysregulation that are associated with an increased risk of developing dementia. Inflammation and inflammasome activation have emerged as a potential link between these disparate pathologies. As diet is a key factor in both the development of metabolic disorders and inflammation, we hypothesize that long term changes in dietary factors can influence nervous system function by regulating inflammasome activity and that this phenotype would be sex-dependent, as sex hormones are known to regulate metabolism and immune processes. Methods 5-week-old male and female transgenic mice expressing a caspase-1 bioluminescent reporter underwent cranial window surgeries and were fed control (65% complex carbohydrates, 15% fat), high glycemic index (65% carbohydrates from sucrose, 15% fat), or ketogenic (1% complex carbohydrates, 79% fat) diet from 6 to 26 weeks of age. Glucose regulation was assessed with a glucose tolerance test following a 4-h morning fast. Bioluminescence in the brain was quantified using IVIS in vivo imaging. Blood cytokine levels were measured using cytokine bead array. 16S ribosomal RNA gene amplicon sequencing of mouse feces was performed to assess alterations in the gut microbiome. Behavior associated with these dietary changes was also evaluated. Results The ketogenic diet caused weight gain and glucose intolerance in both male and female mice. In male mice, the high glycemic diet led to increased caspase-1 biosensor activation over the course of the study, while in females the ketogenic diet drove an increase in biosensor activation compared to their respective controls. These changes correlated with an increase in inflammatory cytokines present in the serum of test mice and the emergence of anxiety-like behavior. The microbiome composition differed significantly between diets; however no significant link between diet, glucose tolerance, or caspase-1 signal was established. Conclusions Our findings suggest that diet composition, specifically the source and quantity of carbohydrates, has sex-specific effects on inflammasome activation in the central nervous system and behavior. This phenotype manifested as increased anxiety in male mice, and future studies are needed to determine if this phenotype is linked to alterations in microbiome composition.

ABSTRACT The impact of chronic indwelling urinary catheters (IUCs) on the composition and stability of the urinary microbiota remains unknown. The primary aim of this study was to describe the urinary microbiomes of geriatric males with chronic IUCs. A secondary aim was to explore clinical catheter-associated urinary tract infection (CAUTI) courses of the participants. Geriatric male patients with chronic IUCs were followed longitudinally. Catheterized urine, catheter tips, and both urethral and periurethral swabs were collected from participants at monthly intervals. Microbes were isolated and identified from each specimen using an enhanced culture method called expanded quantitative urine culture (EQUC) and targeted 16S rRNA gene DNA sequencing. Microbial outcomes were examined both in the absence of urinary symptoms and in the context of clinical diagnosis of CAUTI. Ten male participants (mean age 86 years) were enrolled. Urinary microbiomes differed for each participant. However, within each individual, microbiomes were similar over time and across niches (bladder, catheter, urethra, and periurethra). Within-niche microbiomes differed across individuals, and this was observed over time. The most abundant bacteria isolated from all niches were known uropathogens. Six of 10 individuals met diagnostic criteria for CAUTI at least once during the 12-month observation period, but no evidence of this or antibiotic treatment/response was discernable in our monthly samples. The microbiomes of each participant were unique and remained similar over time and across niches. Longitudinal EQUC or 16S rRNA gene sequencing data could be useful to clinicians when diagnosing or treating possible CAUTI.IMPORTANCECatheter-associated urinary tract infections (CAUTIs) are serious but preventable nosocomial infections. The most common risk factor for developing CAUTI is prolonged use of indwelling urinary catheters (IUCs). This study provides the first longitudinal description of the urinary microbiomes of geriatric males with chronic IUCs, in the absence of urinary signs and symptoms, as a first step toward enhancing our knowledge of the impact of chronic IUCs on the composition and stability of the urinary microbiota. This is an understudied area, particularly for males.

ABSTRACT Lysine and arginine methylation is an important regulator of enzyme activity and transcription in eukaryotes. However, little is known about this covalent modification in bacteria. In this work, we investigated the role of methylation in bacteria. By reanalyzing a large phyloproteomics data set from 48 bacterial strains representing six phyla, we found that almost a quarter of the bacterial proteome is methylated. Many of these methylated proteins are conserved across diverse bacterial lineages, including those involved in central carbon metabolism and translation. Among the proteins with the most conserved methylation sites is ribosomal protein L11 (bL11). bL11 methylation has been a mystery for five decades, as the deletion of its methyltransferase PrmA causes no cell growth defects. Comparative proteomics analysis combined with inorganic polyphosphate and guanosine tetra/pentaphosphate assays of the ΔprmA mutant in Escherichia coli revealed that bL11 methylation is important for stringent response signaling. In the stationary phase, we found that the ΔprmA mutant has impaired guanosine tetra/pentaphosphate production. This leads to a reduction in inorganic polyphosphate levels, accumulation of RNA and ribosomal proteins, and an abnormal polysome profile. Overall, our investigation demonstrates that the evolutionarily conserved bL11 methylation is important for stringent response signaling and ribosomal activity regulation and turnover.IMPORTANCEProtein methylation in bacteria was first identified over 60 years ago. Since then, its functional role has been identified for only a few proteins. To better understand the functional role of methylation in bacteria, we analyzed a large phyloproteomics data set encompassing 48 diverse bacteria. Our analysis revealed that ribosomal proteins are often methylated at conserved residues, suggesting that methylation of these sites may have a functional role in translation. Further analysis revealed that methylation of ribosomal protein L11 is important for stringent response signaling and ribosomal homeostasis.

Objective: To identify possible stone-promoting microbes, we compared the profiles of microbes grown from stones of patients with and without metabolic syndrome (MetS). The association between MetS and urinary stone disease is well established, but the exact pathophysiologic relationship remains unknown. Recent evidence suggests urinary tract dysbiosis may lead to increased nephrolithiasis risk. Methods: At the time of percutaneous nephrolithotomy, bladder urine and stone fragments were collected from patients with and without MetS. Both sample types were subjected to expanded quantitative urine culture (EQUC) and 16 S ribosomal RNA gene sequencing. Results: Fifty-seven patients included 12 controls (21.1%) and 45 MetS patients (78.9%). Both cohorts were similar with respect to demographics and non-MetS comorbidities. No controls had uric acid stone composition. By EQUC, bacteria were detected more frequently in MetS stones (42.2%) compared to controls (8.3%) (p=0.041). Bacteria also were more abundant in stones of MetS patients compared to controls. To validate our EQUC results, we performed 16 S ribosomal RNA gene sequencing. In 12/16 (75.0%) sequence-positive stones, EQUC reliably isolated at least one species of the sequenced genera. Bacteria were detected in both “infectious” and “non-infectious” stone compositions. Conclusion: Bacteria are more common and more abundant in MetS stones than control stones. Our findings support a role for bacteria in urinary stone disease for patients with MetS regardless of stone composition.

Abstract Background Although the human bladder is reported to harbor unique microbiota, our understanding of how these microbial communities interact with their human hosts is limited, mostly owing to the lack of isolates to test mechanistic hypotheses. Niche-specific bacterial collections and associated reference genome databases have been instrumental in expanding knowledge of the microbiota of other anatomical sites, such as the gut and oral cavity. Results To facilitate genomic, functional, and experimental analyses of the human bladder microbiota, we present a bladder-specific bacterial isolate reference collection comprising 1134 genomes, primarily from adult females. These genomes were culled from bacterial isolates obtained by a metaculturomic method from bladder urine collected by transurethral catheterization. This bladder-specific bacterial isolate reference collection includes 196 different species, including representatives of major aerobes and facultative anaerobes, as well as some anaerobes. It captures 72.2% of the genera found when re-examining previously published 16S rRNA gene sequencing of 392 adult female bladder urine samples. Comparative genomic analysis finds that the taxonomies and functions of the bladder microbiota share more similarities with the vaginal microbiota than the gut microbiota. Whole-genome phylogenetic and functional analyses of 186 bladder Escherichia coli isolates and 387 gut Escherichia coli isolates support the hypothesis that phylogroup distribution and functions of Escherichia coli strains differ dramatically between these two very different niches. Conclusions This bladder-specific bacterial isolate reference collection is a unique resource that will enable bladder microbiota research and comparison to isolates from other anatomical sites.

ABSTRACT Bacterial isolates from the human urinary microbiome have been extensively studied for their antibiotic resistance; however, little work has been done on those isolates that are difficult to grow in vitro. This study was designed to qualify a serum-based medium, New York City Broth III (NYCIII), and a broth microdilution method to determine the antibiotic susceptibility of previously underreported or undescribed microbes that have a difficult time growing in standard Mueller-Hinton broth. Here, we demonstrate that NYCIII microbroth dilution can be an effective method for the determination of antibiotic susceptibility of species found in the human urinary microbiome. We show that this method serves well to characterize fastidious and anaerobic urinary microbes that have no Clinical and Laboratory Standards Institute (CLSI) guidelines, including several in the families Aerococcaceae, Lactobacillaceae, or Actinomycetaceae. Previous studies using expanded quantitative urine culture reveal that urine samples from clinical patients are commonly polymicrobial in composition. Thus, we test whether NYCIII can serve as a viable harmonized medium, capable of supporting antibiotic susceptibility testing in a range of fastidious, non-fastidious, and anaerobic urinary microbes. We propose this methodology to be standardized comparable to CLSI standards to allow for resistance testing in uncharacterized urinary bacteria.IMPORTANCEAntibiotic susceptibilities of fastidious and anaerobic bacteria of the human urinary microbiome are largely underreported due to difficulty in growing them in the lab environment. The current standard medium, Muller-Hinton broth, has difficulty supporting the growth of many of these species, leaving microbiologists without a standardized method. To address this need, this study offers a methodology to survey susceptibilities in a high-throughput manner of these understudied microbes with a proposed harmonized medium, NYCIII, which is capable of supporting the growth of both fastidious and non-fastidious urinary microbes. Broader standardization of this method can allow for the development of antibiotic-resistant breakpoints of the many uncharacterized urinary microbes.

Intravesical therapy (IVT) is the standard of care to decrease risk of recurrence and progression for high‐grade nonmuscle‐invasive bladder cancer. However, post‐IVT recurrence remains common and the ability to risk‐stratify patients before or after IVT is limited. In this prospectively designed and accrued cohort study, we examine the utility of urinary comprehensive genomic profiling (uCGP) for predicting recurrence risk following transurethral resection of bladder tumor (TURBT) and evaluating longitudinal IVT response. Urine was collected before and after IVT instillation and uCGP testing was done using the UroAmp™ platform. Baseline uCGP following TURBT identified patients with high (61%) and low (39%) recurrence risk. At 24 months, recurrence‐free survival (RFS) was 100% for low‐risk and 45% for high‐risk patients with a hazard ratio (HR) of 9.3. Longitudinal uCGP classified patients as minimal residual disease (MRD) Negative, IVT Responder, or IVT Refractory with 24‐month RFS of 100%, 50%, and 32%, respectively. Compared with MRD Negative patients, IVT Refractory patients had a HR of 10.5. Collectively, uCGP enables noninvasive risk assessment of patients following TURBT and induction IVT. uCGP could inform surveillance cystoscopy schedules and identify high‐risk patients in need of additional therapy.

Abstract Background Enterococcus faecalis is the most commonly isolated enterococcal species in clinical infection. This bacterium is notorious for its ability to share genetic content within and outside of its species. With this increased proficiency for horizontal gene transfer, tremendous genomic diversity within this species has been identified. Many researchers have hypothesized E. faecalis exhibits niche adaptation to establish infections or colonize various parts of the human body. Here, we hypothesize that E. faecalis strains isolated from the human bladder will carry unique genomic content compared to clinical strains isolated from other sources. Results This analysis includes comparison of 111 E. faecalis genomes isolated from bladder, urogenital, blood, and fecal samples. Phylogenomic comparison shows no association between isolation source and lineage; however, accessory genome comparison differentiates blood and bladder genomes. Further gene enrichment analysis identifies gene functions, virulence factors, antibiotic resistance genes, and plasmid-associated genes that are enriched or rare in bladder genomes compared to urogenital, blood, and fecal genomes. Using these findings as training data and 682 publicly available genomes as test data, machine learning classifiers successfully distinguished between bladder and non-bladder strains with high accuracy. Genes identified as important for this differentiation were often related to transposable elements and phage, including 3 prophage species found almost exclusively in bladder and urogenital genomes. Conclusions E. faecalis strains isolated from the bladder contain unique genomic content when compared to strains isolated from other body sites. This genomic diversity is most likely due to horizontal gene transfer, as evidenced by lack of phylogenomic clustering and enrichment of transposable elements and prophages. Investigation into how these enriched genes influence host-microbe interactions may elucidate gene functions required for successful bladder colonization and disease establishment.

Continued efforts to isolate and sequence bacteria of the urinary tract has increased representation of these species in publicly available databases. This in turn has improved taxonomic classifications of the urinary microbiome (urobiome). Short-read sequencing targeting a variable region(s) of the 16S rRNA gene sequence has been fundamental in characterizing the urobiomes of males and females with and without lower urinary tract symptoms, as well as cancers of the urinary tract. Here, we have compiled a data set of full-length or near-full-length 16S rRNA gene sequences for the urobiome. To generate this data set, we first plated 203 isolates from the bladder on differential media and sequenced their full-length 16S rRNA gene sequence. We combined this data set with publicly available genomes from primarily the female urinary tract. The final data set includes 399 sequences representative of 160 different species from 73 genera. We assessed the ability of publicly available databases to correctly predict these sequences based on the V1-V3, V4, and V4-V6 variable regions. As expected, species designations based upon these variable regions is often not possible or incorrect. We also detected incorrect genus-level classifications. This data set can be used to supplement existing databases, by increasing urobiome species variation, and thus improve future studies characterizing urobiomes.

With the advent of next generation sequencing, it is now appreciated that human urine is not sterile. Recent investigations of the urinary microbiome (urobiome) have provided insights into several urological diseases. Urobiome dysbiosis, defined as non-optimal urine microbiome composition, has been observed in many disorders; however, it is not clear whether this dysbiosis is the cause of urinary tract disorders or a consequence. In addition, immunologically altered disorders are associated with higher rates of urinary tract infections. These disorders include immunoproliferative and immunodeficiency diseases, cancer, and immunosuppressant therapy in transplant recipients. In this review, we examine the current state of knowledge of the urobiome in immunologically altered diseases, its composition and metabolomic consequences. We conclude that more data are required to describe the urobiome in immune altered states, knowledge that could facilitate understanding the role of the urobiome and its pathophysiological effects on urinary tract infections and other disorders of the urinary tract.

ABSTRACT Untreated asymptomatic bacteriuria (ASB) has been associated with adverse pregnancy outcomes. Thus, routine screening by standard urine culture (SUC) and treatment of ASB are currently recommended for all pregnant women. However, SUC often misses microbes detected by expanded quantitative urine culture methods (EQUC) and 16S rRNA gene (amplicon) sequencing. The existence of these microbes (urinary microbiome) challenges the current approach to ASB screening in pregnancy as it is limited by two assumptions: (i) the female bladder is naturally sterile and (ii) SUC identifies all clinically relevant uropathogens. To determine the uniqueness or similarity between urinary and vaginal microbiomes, we performed a prospective observational institutional review board (IRB)-approved cohort study of pregnant women with a singleton pregnancy

The recognition of the Aerococcus urinae complex (AUC) as an emerging uropathogen has led to growing concerns due to a limited understanding of its disease spectrum and antibiotic resistance profiles. Here, we investigated the prevalence of macrolide resistance within urinary AUC isolates, shedding light on potential genetic mechanisms. Phenotypic testing revealed a high rate of macrolide resistance: 45%, among a total of 189 urinary AUC isolates. Genomic analysis identified integrative and conjugative elements (ICEs) as carriers of the macrolide resistance gene ermA, suggesting horizontal gene transfer as a mechanism of resistance. Furthermore, comparison with publicly available genomes of related pathogens revealed high ICE sequence homogeneity, highlighting the potential for cross-species dissemination of resistance determinants. Understanding mechanisms of resistance is crucial for developing effective surveillance strategies and improving antibiotic use. Furthermore, the findings underscore the importance of considering the broader ecological context of resistance dissemination, emphasizing the need for community-level surveillance to combat the spread of antibiotic resistance within the urinary microbiome.

ABSTRACT Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus iners, and Lactobacillus jensenii are dominant species of the urogenital microbiota. Prior studies suggest that these Lactobacillus species play a significant role in the urobiome of healthy females. In our prior genomic analysis of all publicly available L. jensenii and Lactobacillus mulieris genomes at the time (n = 43), we identified genes unique to these two closely related species. This motivated our further exploration here into their genotypic differences as well as into their phenotypic differences. First, we expanded genome sequence representatives of both species to 61 strains, including publicly available strains and nine new strains sequenced here. Genomic analyses conducted include phylogenetics of the core genome as well as biosynthetic gene cluster analysis and metabolic pathway analyses. Urinary strains of both species were assayed for their ability to utilize four simple carbohydrates. We found that L. jensenii strains can efficiently catabolize maltose, trehalose, and glucose, but not ribose, and L. mulieris strains can utilize maltose and glucose, but not trehalose and ribose. Metabolic pathway analysis clearly shows the lack of treB within L. mulieris strains, indicative of its inability to catabolize external sources of trehalose. While genotypic and phenotypic observations provide insight into the differences between these two species, we did not find any association with urinary symptom status. Through this genomic and phenotypic investigation, we identify markers that can be leveraged to clearly distinguish these two species in investigations of the female urogenital microbiota. IMPORTANCE We have expanded upon our prior genomic analysis of L. jensenii and L. mulieris strains, including nine new genome sequences. Our bioinformatic analysis finds that L. jensenii and L. mulieris cannot be distinguished by short-read 16S rRNA gene sequencing alone. Thus, to discriminate between these two species, future studies of the female urogenital microbiome should employ metagenomic sequencing and/or sequence species-specific genes, such as those identified here. Our bioinformatic examination also confirmed our prior observations of differences between the two species related to genes associated with carbohydrate utilization, which we tested here. We found that the transport and utilization of trehalose are key distinguishing traits of L. jensenii, which is further supported by our metabolic pathway analysis. In contrast with other urinary Lactobacillus species, we did not find strong evidence for either species, nor particular genotypes, to be associated with lower urinary tract symptoms (or the lack thereof).

ABSTRACT The microbial community of the urinary tract (urinary microbiota or urobiota) has been associated with human health. Bacteriophages (phages) and plasmids present in the urinary tract, like in other niches, may shape urinary bacterial dynamics. While urinary Escherichia coli strains associated with urinary tract infection (UTI) and their phages have been catalogued for the urobiome, bacterium-plasmid-phage interactions have yet to be explored. In this study, we characterized urinary E. coli plasmids and their ability to decrease permissivity to E. coli phage (coliphage) infection. Putative F plasmids were predicted in 47 of 67 urinary E. coli isolates, and most of these plasmids carried genes that encode toxin-antitoxin (TA) modules, antibiotic resistance, and/or virulence. Urinary E. coli plasmids, from urinary microbiota strains UMB0928 and UMB1284, were conjugated into E. coli K-12 strains. These transconjugants included genes for antibiotic resistance and virulence, and they decreased permissivity to coliphage infection by the laboratory phage P1vir and the urinary phages Greed and Lust. Plasmids in one transconjugant were maintained in E. coli K-12 for up to 10 days in the absence of antibiotic resistance selection; this included the maintenance of the antibiotic resistance phenotype and decreased permissivity to phage. Finally, we discuss how F plasmids present in urinary E. coli strains could play a role in coliphage dynamics and the maintenance of antibiotic resistance in urinary E. coli. IMPORTANCE The urinary tract contains a resident microbial community called the urinary microbiota or urobiota. Evidence exists that it is associated with human health. Bacteriophages (phages) and plasmids present in the urinary tract, like in other niches, may shape urinary bacterial dynamics. Bacterium-plasmid-phage interactions have been studied primarily in laboratory settings and are yet to be thoroughly tested in complex communities. This is especially true of the urinary tract, where the bacterial genetic determinants of phage infection are not well understood. In this study, we characterized urinary E. coli plasmids and their ability to decrease permissivity to E. coli phage (coliphage) infection. Urinary E. coli plasmids, encoding antibiotic resistance and transferred by conjugation into naive laboratory E. coli K-12 strains, decreased permissivity to coliphage infection. We propose a model by which urinary plasmids present in urinary E. coli strains could help to decrease phage infection susceptibility and maintain the antibiotic resistance of urinary E. coli. This has consequences for phage therapy, which could inadvertently select for plasmids that encode antibiotic resistance.

The advent of sensitive enhanced culture (metaculturomic) and culture-independent DNA-based (metagenomic) methods has revealed a rich collection of microbial species that inhabit the human urinary tract. Known as the urinary microbiome, this community of microbes consists of hundreds of distinct species that range across the entire phylogenetic spectrum. This new knowledge clashes with standard clinical microbiology laboratory methods, established more than 60 years ago, that focus attention on a relatively small subset of universally acknowledged uropathogens. Increasing reports support the hypothesis that this focus is too narrow. Single uropathogen reports are common in women with recurrent urinary tract infection (UTI), although wider disruption of their urinary microbiome is likely. Typical “UTI” symptoms occur in patients with “no growth” reported from standard culture and sometimes antibiotics improve these symptoms. Metaculturomic and metagenomic methods have repeatedly detected fastidious, slow growing, and/or anaerobic microbes that are not detected by the standard test in urine samples of patients with lower urinary tract symptoms. Many of these microbes are also detected in serious non-urinary tract infections, providing evidence that they can be opportunistic pathogens. In this review, we present a set of poorly understood, emerging, and suspected uropathogens. The goal is to stimulate research into the biology of these microbes with a focus on their life as commensals and their transition into pathogens

Diagnosis and treatment of urinary tract infections (UTIs) remains stagnant. The presumption that a patient either has a UTI or does not (binary choice) is inappropriately simplistic. Laboratory diagnostic tests have not advanced for decades. The goal of UTI treatment has not been rigorously defined and may increase the prescription of potentially harmful, inappropriate antibiotics. Despite the high incidence of UTI diagnoses, the high cost of UTI treatment, and increasing concerns associated with antimicrobial resistance, the development of novel and more accurate UTI tests has not been considered a priority, in part due to the general perception that current UTI care is already sufficient. In this review, we discuss the importance of improving UTI diagnostic testing to improve treatment outcomes. We discuss the problems associated with UTI diagnosis. Urinary microbes are alive and exist in both healthy and symptomatic individuals—urine is not sterile. We specifically outline the limitations of standard urine culture methods used by clinical microbiology laboratories, explaining clearly why such methods cannot be considered to be the “gold standard,” as standard culture methods underreport most of the urinary tract microbes, including some acknowledged and many emerging uropathogens. We do not recommend abandonment of this test, as no universally accepted substitute yet exists. However, we strongly encourage the development of new and improved diagnostic tests that can both improve outcomes and preserve antibiotic stewardship.

ABSTRACT Streptococcus anginosus is a prevalent member of the human flora. While it has been found in the microbiota of “healthy” asymptomatic individuals, it has also been associated with genitourinary tract infections and bacteremia. Based upon multilocus sequence analysis, two subspecies and two genomosubspecies have been characterized for the species. We previously conducted whole-genome sequencing of 85 S. anginosus isolates from the urinary tract. Here, we present genomic analysis of this species, including isolates from the urinary tract as well as gut and fecal, vaginal, oral, respiratory, and blood and heart samples. Average nucleotide identity and core genome analysis revealed that these strains form two distinct groups. Group 1 is comprised of the S. anginosus type strain and other previously identified S. anginosus subspecies and genomosubspecies, including isolates from throughout the human body. In contrast, group 2 consists of predominantly urinary streptococci (n = 77; 85.6%). Both of these S. anginosus groups are distinct from other members of the Streptococcus anginosus group (SAG) species S. intermedius and S. constellatus. Genes conserved among all strains of one group but not in any strains in the other group were next identified. Group 1 strains included genes found in S. intermedius and S. constellatus, suggesting that they were lost within the ancestor of the group 2 strains. In contrast, genes unique to the group 2 strains were homologous to more distant streptococci, indicative of acquisition via horizontal gene transfer. These genes are ideal candidates for use as marker genes to distinguish between the two groups in the human microbiota. IMPORTANCE Whole-genome analysis of S. anginosus strains provides greater insight into the diversity of this species than from marker genes alone. Our investigation of 166 publicly available S. anginosus genomes via average nucleotide identity and core genome analysis revealed two phylogenomically distinct groups of this species, with one group almost exclusively consisting of isolates from the urinary tract. In contrast, only 8 urinary strains were identified within the other group, which contained the S. anginosus type strain, as well as all identified subspecies and genomosubspecies. While genomic analysis suggested that this urinary group of S. anginosus is genomically different from the previously characterized S. anginosus subspecies, phenotypic characterization is still needed. Given prior reports of the prevalence of S. anginosus in the urinary tract of both continent and incontinent females, future studies are needed to investigate if the symptom state of the urinary tract is associated with these two different groups.

IntroductionIntravesical therapy (IVT), including Bacillus Calmette-Guérin (BCG), is the standard of care for high grade (HG) non-muscle invasive bladder cancer (NMIBC). Despite the use of IVT, many patients recur after treatment. The bladder microbiome and its role in disease processes has recently risen to prominence. We aim to characterize changes that occur in the bladder microbiome over the course of intravesical therapy and assess whether these changes correlate with outcomes in patients with NMIBC.MethodsPatients with NMIBC undergoing induction BCG or intravesical therapy were prospectively enrolled from January 2019 to March 2020. Patients with clinical T2 or greater pathology or active urinary tract infection at enrollment were excluded. Twenty-nine patients had catheterized (bladder) urine samples collected prior to induction intravesical therapy and prior to each IVT instillation. Twenty-seven received BCG while 2 received intravesical gemcitabine. Bacteria were identified using 16S ribosomal RNA gene sequencing. Bladder microbiome changes were evaluated and differences between patients who recurred and patients who did not recur after IVT were investigated.ResultsAcross the 29 patients analyzed, bacterial richness decreased significantly following intravesical therapy (Richness, P=0.01). Evenness and overall diversity did not change significantly (Pielou, P=0.62; Shannon, P=0.13). Patients who experienced recurrence had a higher relative abundance of Aerococcus in their urine (P

Anthrax, a severe zoonotic disease, is infrequently reported in anthrax-endemic regions of Pakistan. Despite clinical reports indicating its presence, particularly cutaneous anthrax, there is insufficient laboratory evidence regarding disease occurrence and environmental persistence. The present study aimed to confirm Bacillus anthracis presence, accountable for animal mortality and human infection, while exploring environmental transmission factors. Between March 2019 and July 2021, a total of 19 outbreaks were documented. Of these, 11 affected sheep/goats in Zhob district and 8 affected cattle/sheep in Bajour Agency. Clinical signs suggestive of Bacillus anthracis outbreak were observed in 11 animals. Blood and swab samples were collected for confirmation. The study followed a One Health approach, analyzing animal, environmental (soil/plant), and human samples. Of the 19 outbreaks, 11 were confirmed positive for anthrax based on growth characteristics, colony morphology, and PCR. Soil and plant root samples from the outbreak areas were collected and analyzed microscopically and molecularly. Cutaneous anthrax was observed in six humans, and swab samples were taken from the lesions. Human serum samples (n = 156) were tested for IgG antibodies against PA toxin and quantitative analysis of anthrax toxin receptor 1 (ANTXR1). Bacillus anthracis was detected in 65 out of 570 (11.40%) soil samples and 19 out of 190 (10%) plant root samples from the outbreak areas. Four out of six human samples from cutaneous anthrax lesions tested positive for Bacillus anthracis. Human anthrax seroprevalence was found to be 11% and 9% in two districts, with the highest rates among butchers and meat consumers. The highest ANTXR1 levels were observed in butchers, followed by meat consumers, farm employees, meat vendors, veterinarians, and farm owners. These findings highlight the persistence of anthrax in the region and emphasize the potential public health risks.

Due to its frequent association with urinary tract infections (UTIs), Escherichia coli is the best characterized constituent of the urinary microbiota (urobiome). However, uropathogenic E. coli is just one member of the urobiome. In addition to bacterial constituents, the urobiome of both healthy and symptomatic individuals is home to a diverse population of bacterial viruses (bacteriophages). A prior investigation found that most bacterial species in the urobiome are lysogens, harboring one or more phages integrated into their genome (prophages). Many of these prophages are temperate phages, capable of entering the lytic cycle and thus lysing their bacterial host. This transition from the lysogenic to lytic life cycle can impact the bacterial diversity of the urobiome. While many phages that infect E. coli (coliphages) have been studied for decades in the laboratory setting, the coliphages within the urobiome have yet to be cataloged. Here, we investigated the diversity of urinary coliphages by first identifying prophages in all publicly available urinary E. coli genomes. We detected 3,038 intact prophage sequences, representative of 1,542 unique phages. These phages include both novel species as well as species also found within the gut microbiota. Ten temperate phages were isolated from urinary E. coli strains included in our analysis, and we assessed their ability to infect and lyse urinary E. coli strains. We also included in these host range assays other urinary coliphages and laboratory coliphages. The temperate phages and other urinary coliphages were successful in lysing urinary E. coli strains. We also observed that coliphages from non-urinary sources were most efficient in killing urinary E. coli strains. The two phages, T2 and N4, were capable of lysing 83.5% (n = 86) of strains isolated from females with UTI symptoms. In conclusion, our study finds a diverse community of coliphages in the urobiome, many of which are predicted to be temperate phages, ten of which were confirmed here. Their ability to infect and lyse urinary E. coli strains suggests that urinary coliphages may play a role in modulating the E. coli strain diversity of the urobiome.

ABSTRACT Emerging studies reveal unique bacterial communities in the human bladder, with alteration of composition associated to disease states. Systemic lupus erythematosus (SLE) is a complex autoimmune disease that is characterized by frequent impairment of the kidney. Here, we explored the bladder microbiome, metabolome, and cytokine profiles in SLE patients, as well as correlations between microbiome and metabolome, cytokines, and disease profiles. We recruited a group of 50 SLE patients and 50 individually matched asymptomatic controls. We used transurethral catheterization to collect urine samples, 16S rRNA gene sequencing to profile bladder microbiomes, and liquid chromatography-tandem mass spectrometry to perform untargeted metabolomic profiling. Compared to controls, SLE patients possessed unique bladder microbial communities and increased alpha diversity. These differences were accompanied by differences in urinary metabolomes, cytokines, and patients’ disease profiles. The SLE-enriched genera, including Bacteroides, were positively correlated with several SLE-enriched metabolites, including olopatadine. The SLE-depleted genera, such as Pseudomonas, were negatively correlated to SLE-depleted cytokines, including interleukin-8. Alteration of the bladder microbiome was associated with disease profile. For example, the genera Megamonas and Phocaeicola were negatively correlated with serum complement component 3, and Streptococcus was positively correlated with IgG. Our present study reveals associations between the bladder microbiome and the urinary metabolome, cytokines, and disease phenotypes. Our results could help identify biomarkers for SLE. IMPORTANCE Contrary to dogma, the human urinary bladder possesses its own unique bacterial community with alteration of composition associated with disease states. Systemic lupus erythematosus (SLE) is a complex autoimmune disease often characterized by kidney impairment. Here, we explored the bladder microbiome, metabolome, and cytokine profiles in SLE patients, as well as correlations between the microbiome and metabolome, cytokines, and disease profiles. Compared to controls, SLE patients possessed a unique bladder microbial community and elevated alpha diversity. These differences were accompanied by differences in bladder metabolomes, cytokines, and patients’ disease profiles. SLE-enriched genera were positively correlated with several SLE-enriched metabolites. SLE-depleted genera were negatively correlated to SLE-depleted cytokines. Alteration of the bladder microbiome was associated with disease profile. Thus, our study reveals associations between the bladder microbiome and the bladder metabolome, cytokines, and disease phenotypes. These results could help identify biomarkers for SLE.

ABSTRACT Nε-lysine acetylation is a common posttranslational modification observed in diverse species of bacteria. Aside from a few central metabolic enzymes and transcription factors, little is known about how this posttranslational modification regulates protein activity. In this work, we investigated how lysine acetylation affects translation in Escherichia coli. In multiple species of bacteria, ribosomal proteins are highly acetylated at conserved lysine residues, suggesting that this modification may regulate translation. In support of this hypothesis, we found that the addition of either of the acetyl donors acetyl phosphate and acetyl-coenzyme A inhibits translation but not transcription using an E. coli cell-free system. Further investigations using in vivo assays revealed that acetylation does not appear to alter the rate of translation elongation but, rather, increases the proportions of dissociated 30S and 50S ribosomes, based on polysome profiles of mutants or growth conditions known to promote lysine acetylation. Furthermore, ribosomal proteins are more acetylated in the disassociated 30S and 50S ribosomal subunits than in the fully assembled 70S complex. The effect of acetylation is also growth rate dependent, with disassociation of the subunits being most pronounced during late-exponential and early-stationary-phase growth—the same growth phase where protein acetylation is greatest. Collectively, our data demonstrate that lysine acetylation inhibits translation, most likely by interfering with subunit association. These results have also uncovered a new mechanism for coupling translation to the metabolic state of the cell. IMPORTANCE Numerous cellular processes are regulated in response to the metabolic state of the cell. One such regulatory mechanism involves lysine acetylation, a covalent modification involving the transfer of an acetyl group from central metabolite acetyl-coenzyme A or acetyl phosphate to a lysine residue in a protein. This posttranslational modification is known to regulate some central metabolic enzymes and transcription factors in bacteria, though a comprehensive understanding of its effect on cellular physiology is still lacking. In the present study, lysine acetylation was also found to inhibit translation in Escherichia coli by impeding ribosome association, most likely by disrupting salt bridges along the binding interface of the 30S and 50S ribosomal subunits. These results further our understanding of lysine acetylation by uncovering protein synthesis as a new target of regulation and aid in the design of bacteria for biotechnology applications where the growth conditions are known to promote lysine acetylation.

The discovery of the urinary microbiome (urobiome) has created opportunities for urinary health researchers who study a wide variety of human health conditions. This manuscript describes an analysis of catheterized urine samples obtained from 1,004 urobiome study participants with the goal of identifying the most abundant and/or prevalent (common) taxa in five clinically relevant cohorts: unaffected adult women (n=346, 34.6%), urgency urinary incontinence (UUI) (n=255, 25.5%), stress urinary incontinence (SUI) (n=50, 5.0%), urinary tract infection (UTI) (n=304, 30.4%), and interstitial cystitis/painful bladder syndrome (IC/PBS) (n=49, 4.9%). Urine was collected via transurethral catheter and assessed for microbes with the Expanded Quantitative Urine Culture (EQUC) technique. For this combined analytic cohort, the mean age was 59 ± 16; most were Caucasian (n=704, 70.2%), Black (n=137, 13.7%), or Hispanic (n=130, 13.0%), and the mean BMI was 30.4 ± 7.7. Whereas many control or IC/PBS cohort members were EQUC-negative (42.4% and 39.8%, respectively), members of the other 3 cohorts were extremely likely to have detectable microbes. The detected urobiomes of the controls and IC/PBS did not differ by alpha diversity or genus level composition and differed by only a few species. The other 3 cohorts differed significantly from the controls. As expected, Escherichia was both prevalent and highly abundant in the UTI cohort, but other taxa also were prevalent at more moderate abundances, including members of the genera Lactobacillus, Streptococcus, Staphylococcus, Corynebacterium, Actinomyces, and Aerococcus. Members of these genera were also prevalent and highly abundant in members of the UUI cohort, especially Streptococcus anginosus. Intriguingly, these taxa were also detected in controls but at vastly lower levels of both prevalence and abundance, suggesting the possibility that UUI-associated symptoms could be the result of an overabundance of typical urobiome constituents. Finally, prevalence and abundance of microbes in the SUI cohort were intermediate to those of the UUI and control cohorts.These observations can inform the next decade of urobiome research, with the goal of clarifying the mechanisms of urobiome community composition and function. There is tremendous potential to improve diagnosis, evaluation and treatment for individuals affected with a wide variety of urinary tract disorders.

ABSTRACT The urinary tract has a microbial community (the urinary microbiota or urobiota) that has been associated with human health. Whole genome sequencing of bacteria is a powerful tool, allowing investigation of the genomic content of the urobiota, also called the urinary microbiome (urobiome). Bacterial plasmids are a significant component of the urobiome yet are understudied. Because plasmids can be vectors and reservoirs for clinically relevant traits, they are important for urobiota dynamics and thus may have relevance to urinary health. In this project, we sought plasmids in 11 clinically relevant urinary species: Aerococcus urinae, Corynebacterium amycolatum, Enterococcus faecalis, Escherichia coli, Gardnerella vaginalis, Klebsiella pneumoniae, Lactobacillus gasseri, Lactobacillus jensenii, Staphylococcus epidermidis, Streptococcus anginosus, and Streptococcus mitis. We found evidence of plasmids in E. faecalis, E. coli, K. pneumoniae, S. epidermidis, and S. anginosus but insufficient evidence in other species sequenced thus far. Some identified plasmidic assemblies were predicted to have putative virulence and/or antibiotic resistance genes, although the majority of their annotated coding regions were of unknown predicted function. In this study, we report on plasmids from urinary species as a first step to understanding the role of plasmids in the bacterial urobiota. IMPORTANCE The microbial community of the urinary tract (urobiota) has been associated with human health. Whole genome sequencing of bacteria permits examination of urobiota genomes, including plasmids. Because plasmids are vectors and reservoirs for clinically relevant traits, they are important for urobiota dynamics and thus may have relevance to urinary health. Currently, urobiota plasmids are understudied. Here, we sought plasmids in 11 clinically relevant urinary species. We found evidence of plasmids in E. faecalis, E. coli, K. pneumoniae, S. epidermidis, and S. anginosus but insufficient evidence in the other 6 species. We identified putative virulence and/or antibiotic resistance genes in some of the plasmidic assemblies, but most of their annotated coding regions were of unknown function. This is a first step to understanding the role of plasmids in the bacterial urobiota.

ABSTRACT The human bladder contains bacteria, even in the absence of infection. Interest in studying these bacteria and their association with bladder conditions is increasing. However, the chosen experimental method can limit the resolution of the taxonomy that can be assigned to the bacteria found in the bladder. 16S rRNA amplicon sequencing is commonly used to identify bacteria in urinary specimens, but it is typically restricted to genus-level identification. Our primary aim here was to determine if accurate species-level identification of bladder bacteria is possible using 16S rRNA amplicon sequencing. We evaluated the ability of different classification schemes, each consisting of combinations of a reference database, a 16S rRNA gene variable region, and a taxonomic classification algorithm to correctly classify bladder bacteria. We show that species-level identification is possible and that the reference database chosen is the most important component, followed by the 16S variable region sequenced. IMPORTANCE Accurate species-level identification from culture-independent techniques is of importance for microbial niches that are less well characterized, such as that of the bladder. 16S rRNA amplicon sequencing, a common culture-independent way to identify bacteria, is often critiqued for lacking species-level resolution. Here, we extensively evaluate classification schemes for species-level bacterial annotation of 16S amplicon data from bladder bacteria. Our results show that the proper choice of taxonomic database and variable region of the 16S rRNA gene sequence makes species level identification possible. We also show that this improvement can be achieved through the more careful application of existing methods and resources. Species-level information may deepen our understanding of associations between bacteria in the bladder and bladder conditions such as lower urinary tract symptoms and urinary tract infections.

ABSTRACT Urobiome research has the potential to advance the understanding of a wide range of diseases, including lower urinary tract symptoms and kidney disease. Many scientific areas have benefited from early research method consensus to facilitate the greater, common good. This consensus document, developed by a group of expert investigators currently engaged in urobiome research (UROBIOME 2020 conference participants), aims to promote standardization and advances in this field by the adoption of common core research practices. We propose a standardized nomenclature as well as considerations for specimen collection, preservation, storage, and processing. Best practices for urobiome study design include our proposal for standard metadata elements as part of core metadata collection. Although it is impractical to follow fixed analytical procedures when analyzing urobiome data, we propose guidelines to document and report data originating from urobiome studies. We offer this first consensus document with every expectation of subsequent revision as our field progresses.

In recent years, the clinical significance of Aerococcus urinae has been increasingly recognized. A. urinae has been implicated in cases of urinary tract infection (UTI; acute cystitis and pyelonephritis) in both male and female patients, ranging from children to older adults. Aerococcus urinae can also be invasive, causing urosepsis, endocarditis, and musculoskeletal infections. Mechanisms of pathogenesis in A. urinae infections are poorly understood, largely due to the lack of an animal model system. In response to this gap, we developed a model of A. urinae urinary tract infection in mice. We compared A. urinae UTI in female C3H/HeN and C57BL/6 mice and compared four clinical isolates of A. urinae isolated from patients with UTI, urgency urinary incontinence, and overactive bladder. Our data demonstrate that host genetic background modulates A. urinae UTI. Female C57BL/6 female mice rapidly cleared the infection. Female C3H/HeN mice, which have inherent vesicoureteral reflux that flushes urine from the bladder up into the kidneys, were susceptible to prolonged bacteriuria. This result is consistent with the fact that A. urinae infections most frequently occur in patients with underlying urinary tract abnormalities or disorders that make them susceptible to bacterial infection. Unlike uropathogens such as E. coli, which cause infection and inflammation both of the bladder and kidneys in C3H/HeN mice, A. urinae displayed tropism for the kidney, persisting in kidney tissue even after clearance of bacteria from the bladder. Aerococcus urinae strains from different genetic clades displayed varying propensities to cause persistent kidney infection. Aerococcus urinae infected kidneys displayed histological inflammation, neutrophil recruitment and increased pro-inflammatory cytokines. These results set the stage for future research that interrogates host-pathogen interactions between A. urinae and the urinary tract.

ABSTRACT To determine whether functionally relevant questions associated with the urinary or gut microbiome and urinary stone disease (USD) can be answered from metagenome-wide association studies (MWAS), we performed the most comprehensive meta-analysis of published clinical MWAS in USD to date, using publicly available data published prior to April 2021. Six relevant studies met inclusion criteria. For alpha-diversity, significant differences were noted between USD status, stone composition, sample type, study location, age, diet, and sex. For beta-diversity, significant differences were noted by USD status, stone composition, sample type, study location, antibiotic use (30 days and 12 months before sampling), sex, hypertension, water intake, body habitus, and age. Prevotella and Lactobacillus in the gut and urinary tract, respectively, were associated with healthy individuals, while Enterobacteriaceae was associated with USD in the urine and stones. Paradoxically, other Prevotella strains were also strongly associated with USD in the gut microbiome. When data were analyzed together, USD status, stone composition, age group, and study location were the predominant factors associated with microbiome composition. Meta-analysis showed significant microbiome differences based on USD status, stone composition, age group or study location. However, analyses were limited by a lack of public data from published studies, metadata collected, and differing study protocols. Results highlight the need for field-specific standardization of experimental protocols in terms of sample collection procedures and the anatomical niches to assess, as well as in defining clinically relevant metadata and subphenotypes such as stone composition. IMPORTANCE Studies focused on the microbiome broadly support the hypothesis that the microbiome influences the onset of chronic diseases such as urinary stone disease. However, it is unclear what environmental factors shape the microbiome in ways that increase the risk for chronic disease. In addition, it is unclear how differences in study methodology can impact the results of clinical metagenome-wide association studies. In the current meta-analysis, we show that age, stone composition, and study location are the predominant factors that associate with the microbiome and USD status. Furthermore, we reveal differences in results based on specific analytical protocols, which impacts the interpretation of any microbiome study.

The EcoCyc model-organism database collects and summarizes experimental data for Escherichia coli K-12. EcoCyc is regularly updated by the manual curation of individual database entries, such as genes, proteins, and metabolic pathways, and by the programmatic addition of results from select high-throughput analyses. Updates to the Pathway Tools software that supports EcoCyc and to the web interface that enables user access have continuously improved its usability and expanded its functionality. This article highlights recent improvements to the curated data in the areas of metabolism, transport, DNA repair, and regulation of gene expression. New and revised data analysis and visualization tools include an interactive metabolic network explorer, a circular genome viewer, and various improvements to the speed and usability of existing tools.

Staphylococci can cause a wide array of infections that can be life threatening. These infections become more deadly when the isolates are antibiotic resistant and thus harder to treat. Many resistance determinants are plasmid-mediated; however, staphylococcal plasmids have not yet been fully characterized. In particular, plasmids and their contributions to antibiotic resistance have not been investigated within the Arab states, where antibiotic use is not universally regulated. Here, we characterized the putative plasmid content among 56 Staphylococcus aureus and 10 Staphylococcus haemolyticus clinical isolates from Alexandria, Egypt. Putative plasmid sequences were detected in over half of our collection. In total, we identified 72 putative plasmid sequences in 27 S. aureus and 1 S. haemolyticus isolates. While these isolates typically carried one or two plasmids, we identified one isolate—S. aureus AA53—with 11 putative plasmids. The plasmid sequences most frequently encoded a Rep_1, RepL, or PriCT_1 type replication protein. As expected, antibiotic resistance genes were widespread among the identified plasmid sequences. Related plasmids were identified amongst our clinical isolates; homologous plasmids present in multiple isolates clustered into 11 groups based upon sequence similarity. Plasmids from the same cluster often shared antibiotic resistance genes, including blaZ, which is associated with β-lactam resistance. Our analyses suggest that plasmids are a key factor in the pathology and epidemiology of S. aureus in Egypt. A better characterization of plasmids and the role they contribute to the success of Staphylococci as pathogens will guide the design of effective control strategies to limit their spread.

Prior research into the bacterium Gardnerella vaginalisG. vaginalis

The human body harbors numerous populations of microorganisms in various ecological niches. Some of these microbial niches, such as the human gut and the respiratory system, are well studied. One system that has been understudied is the urinary tract, primarily because it has been considered sterile in the absence of infection. Thanks to modern sequencing and enhanced culture techniques, it is now known that a urinary microbiota exists. The implication is that these species live as communities in the urinary tract, forming microbial ecosystems. However, the interactions between species in such an ecosystem remains unknown. Various studies in different parts of the human body have highlighted the ability of the pre-existing microbiota to alter the course of infection by impacting the pathogenicity of bacteria either directly or indirectly. For the urinary tract, the effect of the resident microbiota on uropathogens and the phenotypic microbial interactions is largely unknown. No studies have yet measured the response of uropathogens to the resident urinary bacteria. In this study, we investigate the interactions between uropathogens, isolated from elderly individuals suffering from UTIs, and bacteria isolated from the urinary tract of asymptomatic individuals using growth measurements in conditioned media. We observed that bacteria isolated from individuals with UTI-like symptoms and bacteria isolated from asymptomatic individuals can affect each other’s growth; for example, bacteria isolated from symptomatic individuals affect the growth of bacteria isolated from asymptomatic individuals more negatively than vice versa. Additionally, we show that Gram-positive bacteria alter the growth characteristics differently compared to Gram-negative bacteria. Our results are an early step in elucidating the role of microbial interactions in urinary microbial ecosystems that harbor both uropathogens and pre-existing microbiota.

Urinary tract infections (UTIs) are one of the most common human bacterial infections. While UTIs are commonly associated with colonization by Escherichia coli, members of this species also have been found within the bladder of individuals with no lower urinary tract symptoms (no LUTS), also known as asymptomatic bacteriuria. Prior studies have found that both uropathogenic E. coli (UPEC) strains and E. coli isolates that are not associated with UTIs encode for virulence factors. Thus, the reason(s) why E. coli sometimes causes UTI-like symptoms remain(s) elusive. In this study, the genomes of 66 E. coli isolates from adult female bladders were sequenced. These isolates were collected from four cohorts, including women: (1) without lower urinary tract symptoms, (2) overactive bladder symptoms, (3) urgency urinary incontinence, and (4) a clinical diagnosis of UTI. Comparative genomic analyses were conducted, including core and accessory genome analyses, virulence and motility gene analyses, and antibiotic resistance prediction and testing. We found that the genomic content of these 66 E. coli isolates does not correspond with the participant’s symptom status. We thus looked beyond the E. coli genomes to the composition of the entire urobiome and found that the presence of E. coli alone was not sufficient to distinguish between the urobiomes of individuals with UTI and those with no LUTS. Because E. coli presence, abundance, and genomic content appear to be weak predictors of UTI status, we hypothesize that UTI symptoms associated with detection of E. coli are more likely the result of urobiome composition.

ABSTRACT Lactobacilli are dominant members of the “healthy” female urogenital microbiota. One of these species, Lactobacillus jensenii, is routinely identified in the urinary microbiota of women both with and without urinary tract symptoms. In March 2020, the new bacterial species Lactobacillus mulieris was introduced, and phylogenetic and average nucleotide identity analysis identified eight L. jensenii strains that should be classified as members of the L. mulieris species. This prompted our phylogenomic study of all publicly available L. jensenii and L. mulieris genome sequences. While there is little variation in the 16S rRNA gene sequences, the core genome shows a clear distinction between genomes of the two species. We find eight additional strains of the species L. mulieris among these genomes. Furthermore, one strain, currently classified as L. mulieris UMB7784, is distinct from both L. jensenii and L. mulieris strains. As part of our comparative genomic study, we also investigated the genetic content that distinguishes these two species. Unique to the L. jensenii genomes are several genes related to catabolism of disaccharides. In contrast, L. mulieris genomes encode several cell surface and secreted proteins that are not found within the L. jensenii genomes. These L. jensenii-specific and L. mulieris-specific loci provide insight into phenotypic differences of these two species. IMPORTANCE Lactobacillus species play a key role in the health of the urinary tract. For instance, Lactobacillus crispatus and L. jensenii have been found to inhibit uropathogenic Escherichia coli growth. While L. crispatus is typically found only within the microbiota of women without lower urinary tract symptoms (LUTS), L. jensenii has been found in the microbiota of women both with and without LUTS. With the recent introduction of the new species Lactobacillus mulieris, several strains of L. jensenii were reclassified as L. mulieris based upon gene marker and average nucleotide identity. We took a phylogenomic and comparative genomic approach to ascertain the genetic determinants of these two species. Looking at a larger data set, we identified additional L. mulieris strains, including one distinct from other members of the species—L. mulieris UMB7784. Furthermore, we identified unique loci in each species that may have clinical implications.

ABSTRACT Temporal dynamics of certain human microbiotas have been described in longitudinal studies; variability often relates to modifiable factors or behaviors. Early studies of the urinary microbiota preferentially used samples obtained by transurethral catheterization to minimize vulvovaginal microbial contributions. Whereas voided specimens are preferred for longitudinal studies, the few studies that reported longitudinal data were limited to women with lower urinary tract (LUT) symptoms, due to ease of accessing a clinical population for sampling and the impracticality and risk of collecting repeated catheterized urine specimens in a nonclinical population. Here, we studied the microbiota of the LUT of nonsymptomatic, premenopausal women using midstream voided urine (MSU) specimens to investigate relationships between microbial dynamics and personal factors. Using 16S rRNA gene sequencing and a metaculturomics method called expanded quantitative urine culture (EQUC), we characterized the microbiotas of MSU and periurethral swab specimens collected daily for approximately 3 months from a small cohort of adult women. Participants were screened for eligibility, including the ability to self-collect paired urogenital specimens prior to enrollment. In this population, we found that measures of microbial dynamics related to specific participant-reported factors, particularly menstruation and vaginal intercourse. Further investigation of the trends revealed differences in the composition and diversity of LUT microbiotas within and across participants. These data, in combination with previous studies showing relationships between the LUT microbiota and LUT symptoms, suggest that personal factors relating to the genitourinary system may be an important consideration in the etiology, prevention, and/or treatment of LUT disorders. IMPORTANCE Following the discovery of the collective human urinary microbiota, important knowledge gaps remain, including the stability and variability of this microbial niche over time. Initial urinary studies preferentially utilized samples obtained by transurethral catheterization to minimize contributions from vulvovaginal microbes. However, catheterization has the potential to alter the urinary microbiota; therefore, voided specimens are preferred for longitudinal studies. In this report, we describe microbial findings obtained by daily assessment over 3 months in a small cohort of adult women. We found that, similarly to vaginal microbiotas, lower urinary tract (LUT) microbiotas are dynamic, with changes relating to several factors, particularly menstruation and vaginal intercourse. Our study results show that LUT microbiotas are both dynamic and resilient. They also offer novel opportunities to target LUT microbiotas by preventative or therapeutic means, through risk and/or protective factor modification.

The female bladder seems to harbor a poorly characterized indigenous microbiota. Here, the authors isolate and genome-sequence 149 bacterial strains from catheterized urine of 77 women, generating a culture collection representing two thirds of the bacterial diversity within the samples.

ABSTRACT Microbial communities are commonly studied using culture-independent methods, such as 16S rRNA gene sequencing. However, one challenge in accurately characterizing microbial communities is exogenous bacterial DNA contamination, particularly in low-microbial-biomass niches. Computational approaches to identify contaminant sequences have been proposed, but their performance has not been independently evaluated. To identify the impact of decreasing microbial biomass on polymicrobial 16S rRNA gene sequencing experiments, we created a mock microbial community dilution series. We evaluated four computational approaches to identify and remove contaminants, as follows: (i) filtering sequences present in a negative control, (ii) filtering sequences based on relative abundance, (iii) identifying sequences that have an inverse correlation with DNA concentration implemented in Decontam, and (iv) predicting the sequence proportion arising from defined contaminant sources implemented in SourceTracker. As expected, the proportion of contaminant bacterial DNA increased with decreasing starting microbial biomass, with 80.1% of the most diluted sample arising from contaminant sequences. Inclusion of contaminant sequences led to overinflated diversity estimates and distorted microbiome composition. All methods for contaminant identification successfully identified some contaminant sequences, which varied depending on the method parameters used and contaminant prevalence. Notably, removing sequences present in a negative control erroneously removed >20% of expected sequences. SourceTracker successfully removed over 98% of contaminants when the experimental environments were well defined. However, SourceTracker misclassified expected sequences and performed poorly when the experimental environment was unknown, failing to remove >97% of contaminants. In contrast, the Decontam frequency method did not remove expected sequences and successfully removed 70 to 90% of the contaminants. IMPORTANCE The relative scarcity of microbes in low-microbial-biomass environments makes accurate determination of community composition challenging. Identifying and controlling for contaminant bacterial DNA are critical steps in understanding microbial communities from these low-biomass environments. Our study introduces the use of a mock community dilution series as a positive control and evaluates four computational strategies that can identify contaminants in 16S rRNA gene sequencing experiments in order to remove them from downstream analyses. The appropriate computational approach for removing contaminant sequences from an experiment depends on prior knowledge about the microbial environment under investigation and can be evaluated with a dilution series of a mock microbial community.

Post-translational modifications (PTM) decorate proteins to provide functional heterogeneity to an existing proteome. The large number of known PTMs highlights the many ways that cells can modify their proteins to respond to diverse stimuli. Recently, PTMs have begun to receive increased interest because new sensitive proteomics workflows and structural methodologies now allow researchers to obtain large-scale, in-depth and unbiased information concerning PTM type and site localization. However, few PTMs have been extensively assessed for functional consequences, leaving a large knowledge gap concerning the inner workings of the cell. Here, we review understanding of N-𝜀-lysine acetylation in bacteria, a PTM that was largely ignored in bacteria until a decade ago. Acetylation is a modification that can dramatically change the function of a protein through alteration of its properties, including hydrophobicity, solubility, and surface properties, all of which may influence protein conformation and interactions with substrates, cofactors and other macromolecules. Most bacteria carry genes predicted to encode the lysine acetyltransferases and lysine deacetylases that add and remove acetylations, respectively. Many bacteria also exhibit acetylation activities that do not depend on an enzyme, but instead on direct transfer of acetyl groups from the central metabolites acetyl coenzyme A or acetyl phosphate. Regardless of mechanism, most central metabolic enzymes possess lysines that are acetylated in a regulated fashion and many of these regulated sites are conserved across the spectrum of bacterial phylogeny. The interconnectedness of acetylation and central metabolism suggests that acetylation may be a response to nutrient availability or the energy status of the cell. However, this and other hypotheses related to acetylation remain untested.

Polyomaviruses are abundant in the human body. The polyomaviruses JC virus (JCPyV) and BK virus (BKPyV) are common viruses in the human urinary tract. Prior studies have estimated that JCPyV infects between 20 and 80% of adults and that BKPyV infects between 65 and 90% of individuals by age 10. However, these two viruses encode for the same six genes and share 75% nucleotide sequence identity across their genomes. While prior urinary virome studies have repeatedly reported the presence of JCPyV, we were interested in seeing how JCPyV prevalence compares to BKPyV. We retrieved all publicly available shotgun metagenomic sequencing reads from urinary microbiome and virome studies (n = 165). While one third of the data sets produced hits to JCPyV, upon further investigation were we able to determine that the majority of these were in fact BKPyV. This distinction was made by specifically mining for JCPyV and BKPyV and considering uniform coverage across the genome. This approach provides confidence in taxon calls, even between closely related viruses with significant sequence similarity.

Staphylococcus aureus infections are of growing concern given the increased incidence of antibiotic resistant strains. Egypt, like several other countries, has seen alarming increases in methicillin-resistant S. aureus (MRSA) infections. This species can rapidly acquire genes associated with resistance, as well as virulence factors, through mobile genetic elements, including phages. Recently, we sequenced 56 S. aureus genomes from Alexandria Main University Hospital in Alexandria, Egypt, complementing 17 S. aureus genomes publicly available from other sites in Egypt. In the current study, we found that the majority (73.6%) of these strains contain intact prophages, including Biseptimaviruses, Phietaviruses, and Triaviruses. Further investigation of these prophages revealed evidence of horizontal exchange of the integrase for two of the prophages. These Egyptian S. aureus prophages are predicted to encode numerous virulence factors, including genes associated with immune evasion and toxins, including the Panton–Valentine leukocidin (PVL)-associated genes lukF-PV/lukS-PV. Thus, prophages are likely to be a major contributor to the virulence of S. aureus strains in circulation in Egypt.

ABSTRACT Posttranslational modifications, such as Nε-lysine acetylation, regulate protein function. Nε-lysine acetylation can occur either nonenzymatically or enzymatically. The nonenzymatic mechanism uses acetyl phosphate (AcP) or acetyl coenzyme A (AcCoA) as acetyl donor to modify an Nε-lysine residue of a protein. The enzymatic mechanism uses Nε-lysine acetyltransferases (KATs) to specifically transfer an acetyl group from AcCoA to Nε-lysine residues on proteins. To date, only one KAT (YfiQ, also known as Pka and PatZ) has been identified in Escherichia coli. Here, we demonstrate the existence of 4 additional E. coli KATs: RimI, YiaC, YjaB, and PhnO. In a genetic background devoid of all known acetylation mechanisms (most notably AcP and YfiQ) and one deacetylase (CobB), overexpression of these putative KATs elicited unique patterns of protein acetylation. We mutated key active site residues and found that most of them eliminated enzymatic acetylation activity. We used mass spectrometry to identify and quantify the specificity of YfiQ and the four novel KATs. Surprisingly, our analysis revealed a high degree of substrate specificity. The overlap between KAT-dependent and AcP-dependent acetylation was extremely limited, supporting the hypothesis that these two acetylation mechanisms play distinct roles in the posttranslational modification of bacterial proteins. We further showed that these novel KATs are conserved across broad swaths of bacterial phylogeny. Finally, we determined that one of the novel KATs (YiaC) and the known KAT (YfiQ) can negatively regulate bacterial migration. Together, these results emphasize distinct and specific nonenzymatic and enzymatic protein acetylation mechanisms present in bacteria. IMPORTANCE Nε-Lysine acetylation is one of the most abundant and important posttranslational modifications across all domains of life. One of the best-studied effects of acetylation occurs in eukaryotes, where acetylation of histone tails activates gene transcription. Although bacteria do not have true histones, Nε-lysine acetylation is prevalent; however, the role of these modifications is mostly unknown. We constructed an E. coli strain that lacked both known acetylation mechanisms to identify four new Nε-lysine acetyltransferases (RimI, YiaC, YjaB, and PhnO). We used mass spectrometry to determine the substrate specificity of these acetyltransferases. Structural analysis of selected substrate proteins revealed site-specific preferences for enzymatic acetylation that had little overlap with the preferences of the previously reported acetyl-phosphate nonenzymatic acetylation mechanism. Finally, YiaC and YfiQ appear to regulate flagellum-based motility, a phenotype critical for pathogenesis of many organisms. These acetyltransferases are highly conserved and reveal deeper and more complex roles for bacterial posttranslational modification.

ABSTRACT RcsB is a highly conserved transcription regulator of the Rcs phosphorelay system, a complex two-component signal transduction system (N. Majdalani and S. Gottesman, Annu Rev Microbiol 59:379–405, 2005; A. J. Wolfe, Curr Opin Microbiol 13:204–209, 2010, https://doi.org/10.1016/j.mib.2010.01.002; D. J. Clarke, Future Microbiol 5:1173–1184, 2010, https://doi.org/10.2217/fmb.10.83). RcsB plays an important role in virulence and pathogenicity in human hosts by regulating biofilm formation. RcsB can regulate transcription alone or together with its auxiliary transcription regulators by forming heterodimers. This complexity allows RcsB to regulate transcription of more than 600 bacterial genes in response to different stresses (D. Wang et al., Mol Plant Microbe Interact 25:6–17, 2012, https://doi.org/10.1094/MPMI-08-11-0207). Despite increasing knowledge of RcsB importance, molecular mechanisms that drive the ability of RcsB to control transcription of a large number of genes remain unclear. Here, we present crystal structures of unphosphorylated RcsB in complex with the consensus DNA-binding sequence of 22-mer (DNA22) and 18-mer (DNA18) of the flhDC operon from Escherichia coli determined at 3.15- and 3.37-Å resolution, respectively. The results of our structural analysis combined with the results of in vitro binding assays provide valuable insights to the protein regulatory mechanism, demonstrate how RcsB recognizes target DNA sequences, and reveal a unique oligomeric state that allows RcsB to form homo- and heterodimers. This information will help us understand the complex mechanisms of transcriptional regulation by RcsB in bacteria. IMPORTANCE RcsB is a well-studied two-component response regulator of the Rcs phosphorelay system, conserved within the family Enterobacteriaceae, which includes many pathogens. It is a global regulator, controlling more than 5% of bacterial genes associated with capsule biosynthesis, flagellar biogenesis, cell wall biosynthesis, antibiotic resistance, biofilm formation, and virulence in pathogens. Knowledge of RcsB structure represents a unique opportunity to explore mechanisms that regulate the Rcs phosphorelay system and its role in the family Enterobacteriaceae.

ABSTRACT Lysine acetylation is a common protein post-translational modification in bacteria and eukaryotes. Unlike phosphorylation, whose functional role in signaling has been established, it is unclear what regulatory mechanism acetylation plays and whether it is conserved across evolution. By performing a proteomic analysis of 48 phylogenetically distant bacteria, we discovered conserved acetylation sites on catalytically essential lysine residues that are invariant throughout evolution. Lysine acetylation removes the residue’s charge and changes the shape of the pocket required for substrate or cofactor binding. Two-thirds of glycolytic and tricarboxylic acid (TCA) cycle enzymes are acetylated at these critical sites. Our data suggest that acetylation may play a direct role in metabolic regulation by switching off enzyme activity. We propose that protein acetylation is an ancient and widespread mechanism of protein activity regulation. IMPORTANCE Post-translational modifications can regulate the activity and localization of proteins inside the cell. Similar to phosphorylation, lysine acetylation is present in both eukaryotes and prokaryotes and modifies hundreds to thousands of proteins in cells. However, how lysine acetylation regulates protein function and whether such a mechanism is evolutionarily conserved is still poorly understood. Here, we investigated evolutionary and functional aspects of lysine acetylation by searching for acetylated lysines in a comprehensive proteomic data set from 48 phylogenetically distant bacteria. We found that lysine acetylation occurs in evolutionarily conserved lysine residues in catalytic sites of enzymes involved in central carbon metabolism. Moreover, this modification inhibits enzymatic activity. Our observations suggest that lysine acetylation is an evolutionarily conserved mechanism of controlling central metabolic activity by directly blocking enzyme active sites.

Abstract Objective The objective of this study was to characterize the bladder microbiota in pregnancy. Methods A prospective observational study of 51 pregnant women, admitted to a tertiary care hospital, who underwent straight catheterization urine collection or transurethral Foley catheter placement. 16S rRNA gene sequencing and enhanced quantitative urine culture assessed the maternal bladder microbiota with comparisons made to standard urine culture results. Results Enhanced quantitative urine culture and 16S rRNA gene sequencing detected bacteria in the majority of participants. Lactobacillus and Gardnerella were the most commonly detected microbes. In contrast, standard urine culture had a 100% false-negative rate and failed to detect several known or emerging urinary pathogens. Conclusion There are live bacteria in the bladders of most pregnant women. This challenges the definition of asymptomatic bacteriuria.

The changing science of the urinary microbiota and microbiome has both clinical and research implications. This review paper provides an overview of the state of this science, as well as a discussion of the potential for prevention, diagnosis, and treatment of human disease. The history of techniques used for clinical detection of infection are placed into context along with the modern methods of bacterial detection and identification.