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Background In the coronavirus disease 2019 (COVID-19) pandemic, correctional facilities are potential hotspots for transmission. We examined the genomic epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) early in the pandemic in one of the country's largest urban jails. Methods Existing SARS-CoV-2 isolates from 131 detainees at the Cook County Jail in Chicago, Illinois, from March 2020 through May 2020 were analyzed by whole-genome sequencing. Contemporaneous isolates from Rush University Medical Center (Chicago, Illinois) and the Global Initiative on Sharing All Influenza Data (GISAID) were used to identify genetic clusters containing only jail isolates. Transmission windows were identified for each pair of detainees using the date of the SARS-CoV-2–positive test and location data to determine if detainees overlapped in the jail, within a specific building, or within particular living units during transmission windows. Results We identified 29 jail-only clusters that contained 75 of the 132 SARS-CoV-2 isolates from detainees; of these clusters, 17 (58.6%) had individuals who overlapped in the jail during putative transmission windows. Focusing on specific buildings revealed that 2 buildings, a single- and double-cell style of housing. were associated with having detainees infected with similar SARS-CoV-2 genomes during their infectious time period (P <.001). Conclusions Our findings suggest that there was transmission of SARS-CoV-2 in the jail, in the setting of extensive importation of COVID-19 from the community. Numerous infection control practices at intake and during incarceration were implemented in the jail to limit viral spread. Our study shows the importance of genomic analysis in this type of settings and how it can be utilized within infection control protocols. [ABSTRACT FROM AUTHOR]

Storage mites colonize a wide spectrum of food commodities and adaptations to diets have been suggested as mechanisms enabling successful colonization. We characterized the response of seven unique Tyrophagus putrescentiae cultures (5K, 5L, 5N, 5P, 5Pi, 5S, and 5Tk) with different baseline microbiomes to different diets. The offered diets included a rearing diet, protein-enriched diet, oat flakes, and sunflower seeds. Microbiome characterization was performed using 16S ribosomal RNA (rRNA) gene amplicon sequencing and 16S rRNA gene quantitative PCR. The mite culture microbiomes were classified into four groups: (i) Sodalis- dominated (5Pi), (ii) Wolbachia -dominated (5N and 5P), (iii) Cardinium- dominated (5L and 5S), and (iv) asymbiontic (5K and 5Tk) mites dominated by Bacillus and Bartonella. Mite growth rates were most strongly affected by nutrients in the diet, while respiration and microbial community profiles were largely influenced by mite culture. While growth rate was not directly explained by microbiome composition, microbiomes strongly influenced mite fitness as measured by respiration. While diet significantly influenced microbial profiles in all cultures, the effect of diet differed in impact between cultures (5Pi > 5S > 5N > 5K > 5Tk > 5L > 5P). Furthermore, no new bacterial taxa were acquired by mites after dietary changes. Bacteria from the taxa Bacillus, Bartonella- like, Solitalea- like, Kocuria , and Sodalis- like contributed most strongly to differentiating mite-associated microbiomes. [ABSTRACT FROM AUTHOR]

Background: We determined how the vaginal and penile microbiomes contribute to herpes simplex virus type 2 (HSV-2) serostatus within sexual partnerships.Methods: Microbiomes were characterized in cervicovaginal lavage and penile meatal swab specimens through high-throughput 16s ribosomal RNA gene amplicon sequencing. HSV-2 antibody was detected in serum specimens. We modeled vaginal and penile taxa and covariates contributing to HSV-2 status in women and men using bivariate probit analysis.Results: Among 231 couples, HSV-2 was detected in both partners in 78 couples (33.8%), in the woman only in 52 (22.5%),in the man only in 27 (11.7%), and in neither in 74 (32.0%). Among the women (median age, 22 years) 10.9% had human immunodeficiency virus (HIV), and 21.4% had Bacterial vaginosis. Among men (median age, 26 years), 11.8% had HIV, and 55.0% circumcised. In an analysis with adjustment for sociodemographics and Bacterial vaginosis, enrichment of vaginal Gardnerella vaginalis and Lactobacillus iners was associated with increased likelihood of HSV-2 in both partners. Penile taxa (including Ureaplasma and Aerococcus) were associated with HSV-2 in women.Conclusions: We demonstrate that penile taxa are associated with HSV-2 in female partners, and vaginal taxa are associated with HSV-2 in male partners. Our findings suggest that couples-level joint consideration of genital microbiome and sexually transmitted infection or related outcomes could lead to new avenues for prevention. [ABSTRACT FROM AUTHOR]

Background Congregate settings, such as jails, may be a location where colonized detainees transmit methicillin-resistant Staphylococcus aureus (MRSA). We examined MRSA acquisition during incarceration and characterized the genomic epidemiology of MRSA entering the jail and isolated during incarceration. Methods Males incarcerated at the Cook County Jail were enrolled within 72 h of intake and MRSA surveillance cultures collected. Detainees in jail at Day 30 were re-cultured to determine MRSA acquisition. A survey was administered to identify acquisition predictors. Genomic sequencing of surveillance and clinical isolates was integrated with epidemiologic and jail location data to track MRSA transmission pathways. Results 800 males were enrolled; 19% MRSA colonized at intake. Of 184 who reached Day 30 visit, 12 acquired MRSA. Heroin use before entering (OR 3.67, P =.05) and sharing personal items during incarceration (OR = 4.92, P =.01) were predictors of acquisition. Sequenced clinical USA300 isolates (n = 112) were more genetically similar than diverse intake USA300 strains (P <.001), suggesting jail transmission. Four acquired colonization isolates were within 20 single-nucleotide variant (SNVs) of other isolates; 4 were within 20 SNVs of an intake isolate, 2 for an acquisition isolate, and 1 for a clinical isolate. Individuals with genetically similar isolates were more likely to have had overlapping stays in the same buildings. Conclusion There was a high MRSA burden entering jail. Genomic analysis of acquisition and clinical isolates suggests potential spread of incoming strains and networks of spread during incarceration, with spread often occurring among detainees housed in similar locations. Sharing personal items during incarceration is associated with MRSA acquisition and could be a focus for intervention. [ABSTRACT FROM AUTHOR]

Interactions among endosymbiotic bacteria inside their eukaryotic hosts are poorly understood, particularly in mites. The mite Tyrophagus putrescentiae is a common, medically important generalist species that has many intracellular and gut bacterial symbionts. In the experiments, we examined bacterial abundances and composition in mite populations obtained by controlled mixing of stock mite populations that differed in the presence/absence of the major intracellular bacteria Wolbachia and Cardinium. Changes in microbial communities were characterized using 16S ribosomal RNA high-throughput sequencing (pooled mite individuals) and quantitative PCR for key microbial taxa (individual mites). Mite fitness was estimated as a parameter of population growth. We detected that in mixed mite populations, Cardinium and Wolbachia can co-occur in the same mite individual. The presence of Cardinium was negatively correlated with the presence of Wolbachia and Bartonella , while the Bartonella and Wolbachia were positively correlated in individual level samples. Since mixed populations had lower abundances of Wolbachia , while the abundance of Cardinium did not change, we suggest that the presence of Cardinium inhibits the growth of Wolbachia. The mixed mite populations had lower population growth than parental populations. The possible effect of symbionts on the fitness of mixed population is discussed. [ABSTRACT FROM AUTHOR]

Background Methicillin-resistant Staphylococcus aureus (MRSA)—and now USA300 MRSA—is a significant intensive care unit (ICU) pathogen; healthcare worker (HCW) contamination may lead to patient cross-transmission. Methods From September 2015 to February 2016, to study the spread of MRSA, we enrolled HCWs in 4 adult ICUs caring for patients on MRSA contact precautions. Samples were collected from patient body sites and high-touch surfaces in patient rooms. HCW hands, gloves, and personal protective equipment were sampled pre/post-patient encounter. Whole genome sequencing (WGS) was used to compare isolates from patients, HCWs, and environment. Results There were 413 MRSA isolates sequenced (38% USA300, 52% USA100) from 66 patient encounters. Six of 66 HCWs were contaminated with MRSA prior to room entry. Isolates from a single patient encounter were typically either USA100 or USA300; in 8 (12%) encounters both USA300 and USA100 were isolated. WGS demonstrated that isolates from patients, HCWs, and environment often were genetically similar, although there was substantial between-encounter diversity. Strikingly, there were 5 USA100 and 1 USA300 clusters that contained similar strains (<22 single-nucleotide variants [SNVs], with most <10 SNVs) within the cluster despite coming from different encounters, suggesting intra- and inter-ICU spread of strains, that is, 4 of these genomic clusters were from encounters in the same ICU; 5 of 6 clusters occurred within 1 week. Conclusions We demonstrated frequent spread of MRSA USA300 and USA100 strains among patients, environment, and HCWs. WGS identified possible spread within and even between ICUs. Future analysis with detailed contact tracing in conjunction with genomic data may further elucidate pathways of MRSA spread and points for intervention. [ABSTRACT FROM AUTHOR]

In culture, the house dust mite, Dermatophagoides pteronyssinus , shows different growth patterns, but the composition and changes in the associated microbial community during mite culture growth are poorly known. In this study, we analyzed temporal changes in microbial communities including 'internal' communities (inside mites, ingested) and 'environmental' communities (from culture environment). Microbial community structure was correlated with guanine content (a nitrogenous waste product of mites) and mite population density. Both internal and environmental microbial communities were remarkably consistent between biological replicates from the same culture age group and were composed of relatively few dominant taxa–11 bacterial and 3 fungal operational taxonomic units (OTUs). Significant changes over time in microbial community structure in the bulk culture environment and in internal mite samples were observed. The yeast, Saccharomyces cerevisiae , a main component of the mite diet, gradually disappeared during mite culture growth and was replaced by fungi from the genera Aspergillus and Candida in both 'internal' and 'environmental' samples. In environmental samples, bacteria from the genus Lactobacillus and S. cerevisiae were negatively correlated, and Aspergillus and Candida positively correlated, with guanine content. The relative abundance of bacteria from the genus Kocuria increased with mite density but declined with increasing guanine content. The relative abundance of bacteria from the genus Virgibacillus was negatively correlated with mite density in 'internal' samples. Gram-positive bacteria dominated bacterial microbiomes at all time points in our experiments, indicating a more limited possibility for vaccine contamination by bacterial endotoxins (heat-stable lipopolysaccharides produced mostly by Gram-negative bacteria) in our experimental cultures. [ABSTRACT FROM AUTHOR]

Background Jails may facilitate spread of methicillin-resistant Staphylococcus aureus (MRSA) in urban areas. We examined MRSA colonization upon entrance to a large urban jail to determine if there are MRSA transmission networks preceding incarceration. Methods Males incarcerated in Cook County Jail (Chicago) were enrolled, with enrichment for people living with human immunodeficiency virus (PLHIV), within 72 hours of intake. Surveillance cultures assessed prevalence of MRSA colonization. Whole-genome sequencing (WGS) identified preincarceration transmission networks. We examined methicillin-resistant Staphylococcus aureus (MRSA) isolates to determine if there are transmission networks that precede incarceration. A large proportion of individuals enter jail colonized with MRSA. Molecular epidemiology and colonization risk factors provide clues to community reservoirs for MRSA. Results There were 718 individuals (800 incarcerations) enrolled; 58% were PLHIV. The prevalence of MRSA colonization at intake was 19%. In multivariate analysis, methamphetamine use, unstable housing, current/recent skin infection, and recent injection drug use were predictors of MRSA. Among PLHIV, recent injection drug use, current skin infection, and HIV care at outpatient clinic A that emphasizes comprehensive care to the lesbian, gay, bisexual, transgender community were predictors of MRSA. Fourteen (45%) of 31 detainees with care at clinic A had colonization. WGS revealed that this prevalence was not due to clonal spread in clinic but rather to an intermingling of distinct community transmission networks. In contrast, genomic analysis supported spread of USA500 strains within a network. Members of this USA500 network were more likely to be PLHIV (P <.01), men who have sex with men (P <.001), and methamphetamine users (P <.001). Conclusions A large proportion of individuals enter jail colonized with MRSA. Molecular epidemiology and colonization risk factors provide clues to identify colonized detainees entering jail and potential community reservoirs of MRSA. [ABSTRACT FROM AUTHOR]

Municipal solid waste (MSW) landfills are the third largest anthropogenic source of methane (CH4) emissions in the United States. The majority of CH4 generated in landfills is converted to carbon dioxide (CO2) by CH4-oxidizing bacteria (MOB) present in the landfill cover soil, whose activity is controlled by various environmental factors including temperature. As landfill temperature can fluctuate substantially seasonally, rates of CH4 oxidation can also vary, and this could lead to incomplete oxidation. This study aims at analyzing the effect of temperature on CH4 oxidation potential and microbial community structure of methanotrophs in laboratory-based studies of landfill cover soil and cultivated consortia. Soil and enrichment cultures were incubated at temperatures ranging from 6 to 70 °C, and rates of CH4 oxidation were measured, and the microbial community structure was analyzed using 16S rRNA gene amplicon sequencing and shotgun metagenome sequencing. CH4 oxidation occurred at temperatures from 6 to 50 °C in soil microcosm tests, and 6–40 °C in enrichment culture batch tests; maximum rates of oxidation were obtained at 30 °C. A corresponding shift in the soil microbiota was observed, with a transition from putative psychrophilic to thermophilic methanotrophs with increasing incubation temperature. A strong shift in methanotrophic community structure was observed above 30 °C. At temperatures up to 30 °C, methanotrophs from the genus Methylobacter were dominant in soils and enrichment cultures; at a temperature of 40 °C, putative thermophilic methanotrophs from the genus Methylocaldum become dominant. Maximum rate measurements of nearly 195 μg CH4 g−1 day−1 were observed in soil incubations, while observed maximum rates in enrichments were significantly lower, likely as a result of diffusion limitations. This study demonstrates that temperature is a critical factor affecting rates of landfill soil CH4 oxidation in vitro and that changing rates of CH4 oxidation are in part driven by changes in methylotroph community structure. [ABSTRACT FROM AUTHOR]

Background: We examined whether disparities existed in hospital-onset (HO) Staphylococcus aureus bloodstream infections (BSIs) and used whole-genome sequencing (WGS) to identify factors associated with USA300 transmission networks.Methods: We evaluated HO methicillin-susceptible S. aureus (MSSA) and HO methicillin-resistant S. aureus (MRSA) BSIs for 2009-2013 at 2 hospitals and used an adjusted incidence for modeling. WGS and phylogenetic analyses were performed on a sample of USA300 BSI isolates. Epidemiologic data were analyzed in the context of phylogenetic reconstructions.Results: On multivariate analysis, male sex, African-American race, and non-Hispanic white race/ethnicity were significantly associated with HO-MRSA BSIs whereas Hispanic ethnicity was negatively associated (rate ratio, 0.41; P = .002). Intermixing of community-onset and HO-USA300 strains on the phylogenetic tree indicates that these strains derive from a common pool. African-American race was the only factor associated with genomic clustering of isolates.Conclusions: In a multicenter assessment of HO-S. aureus BSIs, African-American race was significantly associated with HO-MRSA but not MSSA BSIs. There appears to be a nexus of USA300 community and hospital transmission networks, with a community factor being the primary driver. Our data suggest that HO-USA300 BSIs likely are due to colonizing strains acquired in the community before hospitalization. Therefore, prevention efforts may need to extend to the community for maximal benefit. [ABSTRACT FROM AUTHOR]

Background. In a community, it is unknown what factors account for transmission of methicillin-resistant Staphylococcus aureus (MRSA). We integrated whole genome sequencing (WGS) and epidemiologic data to identify factors associated with MRSA transmission networks in an urban community. Methods. WGS was performed on colonizing USA300 MRSA isolates from 74 individuals within 72 hours of admission to a public hospital in Chicago, IL. Single nucleotide variants (SNVs) were used to reconstruct the phylogeny of sequenced isolates, and epidemiologic data was overlaid to identify factors associated with transmission networks. Results. The maximum within-patient SNV difference for an individual with multisite colonization was 41 SNVs, with no systematic divergence among body sites. We observed a minimum of 7 SNVs and maximum of 153 SNVs between isolates from different individuals. We identified 4 pairs of individuals whose isolates were within 40 SNVs of each other. Putting our isolates in the context of previously sequenced USA300 isolates from other communities, we identified a 13-member group and two 4-member groups that represent samples from putative local transmission networks. Individuals in these groups were more likely to be African American, to be human immunodeficiency virus-infected, to reside in high detainee release areas, and to be current users of illicit drugs. Conclusions. Using WGS, we observed potential transmission networks in an urban community and that certain epidemiologic factors were associated with inclusion in these networks. Future work with contact tracing and advanced molecular diagnostics may allow for identification of MRSA "epicenters" in the community where interventions can be targeted. [ABSTRACT FROM AUTHOR]

Stromatolites are sedimentary deposits that are the direct result of interactions between microbes and their surrounding environment. Once dominant on ancient Earth, actively forming stromatolites now occur in just a few remote locations around the globe, such as the island of Highborne Cay, Bahamas. Although the stromatolites of Highborne Cay contain a wide range of metabolically diverse organisms, photosynthetic cyanobacteria are the driving force for stromatolite development. In this study, we complement previous morphological data by examining the cyanobacterial phylogenetic and physiological diversity of Highborne Cay stromatolites. Molecular analysis of both clone and culture libraries identified 33 distinct phylotypes within the stromatolites. Culture libraries exhibited several morphologically similar but genetically distinct ecotypes, which may contribute to ecosystem stability within the stromatolites. Several of the cultured isolates exhibited both a positive phototactic response and light-dependent extracellular polymeric secretions production, both of which are critical phenotypes for stromatolite accretion and development. The results of this study reveal that the genetic diversity of the cyanobacterial populations within the Highborne Cay stromatolites is far greater than previous estimates, indicating that the mechanisms of stromatolite formation and accretion may be more complex than had been previously assumed.The ISME Journal (2009) 3, 573–587; doi:10.1038/ismej.2008.129; published online 15 January 2009 [ABSTRACT FROM AUTHOR]

The cyanobacterial community structure and composition of hypersaline mats were characterized in an experiment in which native salinity and sulfate levels were modified. Over the course of approximately 1 year, microbial mats collected from Guerrero Negro (Baja, California Sur, Mexico) were equilibrated to lowered salinity (to 35 p.p.t.) and lowered sulfate (below 1mM) conditions. The structure and composition of the cyanobacterial community in the top 5mm of these mats were examined using a multifaceted cultivation-independent molecular approach. Overall, the relative abundance of cyanobacteria—roughly 20% of the total bacterial community, as assayed with a PCRbased methodology—was not significantly affected by these manipulations. Furthermore, the mat cyanobacterial community was only modestly influenced by the dramatic changes in sulfate and salinity, and the dominant cyanobacteria were unaffected. Community composition analyses confirmed the dominant presence of the cosmopolitan cyanobacterium Microcoleus chthonoplastes, but also revealed the dominance of another Oscillatorian cyanobacterial group, also detected in other hypersaline microbial mats. Cyanobacterial populations increasing in relative abundance under the modified salinity and sulfate conditions were found to be most closely related to other hypersaline microbial mat organisms, suggesting that the development of these mats under native conditions precludes the development of organisms better suited to the less restrictive experimental conditions. These results also indicate that within a significant range of salinity and sulfate concentrations, the cyanobacterial community is remarkably stable. [ABSTRACT FROM AUTHOR]

Microbial colonization of plant seeds and roots is a highly complex process in which soil and plant type can influence the composition of the root-associated and rhizosphere microbial communities. Amendment of compost, a common agricultural technique, introduces exogenous nutrients and microorganisms to the soil–plant environment, and can further influence microbial community composition in the plant environment. Although compost amendments can strongly influence soil and rhizosphere microbial communities, there is evidence that with increasing proximity to the root, plant influences predominate over soil effects. We hypothesized that the ‘rhizosphere effect’ observed with proximity to plant surfaces does not act equally on all microorganisms. To explore this issue, we examined two bacterial taxa that reproducibly colonized seed and root surfaces in an experiment examining the influence of compost amendment on plant-associated bacterial communities. Population-specific analyses revealed striking differences in the ecology of bacteria from the genus Chryseobacterium and the family Oxalobacteraceae in potting mix and plant-associated environments. Seed- and root-colonizing Oxalobacteraceae populations were highly sensitive to plant effects, and phylogenetic analyses of root-colonizing Oxalobacteraceae revealed the presence of root-associated populations that were highly similar, regardless of treatment, and differed from the potting mix populations detected at the same sampling points. Conversely, Chryseobacterium community composition was found to be essentially invariant within treatments, but was strongly influenced by compost amendment. This persistence and stable nature of the Chryseobacterium community composition demonstrates that rhizosphere selection is not the exclusive factor involved in determining the composition of the cucumber spermosphere and rhizosphere communities.The ISME Journal (2007) 1, 291–299; doi:10.1038/ismej.2007.33; published online 24 May 2007 [ABSTRACT FROM AUTHOR]

We analyzed bacterial communities in two cow manure composts derived from the same feed manure and composted in the same location, but composted with different carbon amendments, and in peat-based potting mixes amended with these composts. Bacterial communities were characterized by PCR-denaturing gradient gel electrophoresis (DGGE) analysis of extracted DNAs, and population fingerprints generated for each sample were compared. Sequence analyses of dominant DGGE bands revealed that members of the phylum Bacteroidetes were the most dominant bacteria detected in this study (19 of 31 clones). These analyses demonstrate that bacterial community profiles of individual composts were highly similar, as were profiles of compost-amended potting mixes. However, potting mix profiles differed substantially from the original compost profiles and from that of the peat base. These data indicate that highly similar bacterial populations were active in the two composts, and suggest that the effects of the initial carbon amendment on the mature compost bacterial communities were minor, while factors such as the feed manure and composting location may have been more influential. [Copyright &y& Elsevier]