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Background: Stenotrophomonas maltophilia, a pathogen that colonizes medical equipment and causes nosocomial infections due to its ability to form biofilms, has high mortality rates. This study investigated the risk factors related to mortality in patients who were diagnosed with S. maltophilia bacteremia. Methods: It is a multi-center, retrospective ad observational cohort study. The demographic characteristics, clinical findings, microbiological data, and risk factors for patients were obtained from the medical records of patients at ten different hospitals between January 1, 2018, and June 30, 2023. Results: The study included a total of 321 patients. The observed thirty-day mortality rate was 46.1%. A central venous catheter (CVC) was present in 276 patients (86%), and in 66 of these patients (23.9%) the CVC was removed. While only 18 patients (5.6%) received appropriate empirical antibiotics, 242 (75.4%) patients received appropriate antibiotics according to antimicrobial susceptibility test (AST) results and treatment revisions. Multivariate analysis revealed that advanced age (hazard ratio [HR] = 1.02; 95% confidence interval [CI]: 1.00– 1.03), appropriate antibiotic treatment (HR = 0.35; 95% CI: 0.23–0.52), and removal of central venous catheters (HR = 0.31; 95% CI: 0.16–0.60) were significantly related to reduced mortality. Conclusions: S. maltophilia is a significant pathogen, and to reduce its high mortality rate, removal of the CVC and switching to appropriate antibiotics should be performed as soon as possible. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia , an environmentally ubiquitous microbe, is a challenging opportunistic pathogen in the hospital setting. Neonates are particularly vulnerable to infection with Stenotrophomonas but information on presentation, therapeutic response and outcome of such infection in this population is limited. To expand this knowledge, we report here a series of five cases. All the five neonates having S. maltophilia sepsis, were preterms (27–32 weeks), very low birth weight, with clinical presentation within three weeks of life, with respiratory involvement presenting as respiratory distress due to pulmonary haemorrhage, non-specific features like lethargy, altered blood sugar levels and haemodynamic instability. The microbe was sensitive to amikacin, ceftazidime, cotrimoxazole, gentamycin, levofloxacin and minocycline except in two cases showing levofloxacin resistance. All but one neonate survived with morbidities like retinopathy of prematurity, bronchopulmonary dysplasia and metabolic bone disease. [ABSTRACT FROM AUTHOR]

Previous reports focusing on cefiderocol susceptibility against Stenotrophomonas maltophilia have included a large number of noninvasive or colonized isolates, and data focusing on invasive S. maltophilia strains are still lacking. We retrospectively investigated the cefiderocol susceptibility of stored S. maltophilia strains that caused bacteremia at two Japanese hospitals. The MIC50 and MIC90 were 0.06 μg/mL and 0.25 μg/mL, respectively, while the susceptibility rate was 99.3% (current CLSI breakpoint criteria). Our results provide the MIC distribution of bacteremic S. maltophilia isolates in Japan and show the preserved cefiderocol susceptibility of S. maltophilia among clinically invasive pathogenic strains. [ABSTRACT FROM AUTHOR]

Background: Limited information exists on carriage of multidrug-resistant organisms (MDRO) by health workers (HWs) in primary care settings. This study aims to determine the prevalence of MDRO carriage among HWs in primary care and to identify associated risk factors. Methods: A cross-sectional study was conducted across all 12 primary care units in São Caetano do Sul-SP, Brazil, from October to December 2023. Self-collected samples (nasal, oropharyngeal, and inguinal) were obtained. Environment cultures (potable water, sewage and stream water) were evaluated. Stenotrophomonas maltophilia isolates (human and environmental) were typed. Results: The study included 265/288 (92%) of HWs in primary care teams, mostly women with a median age of 47 years (IQR 38—57); 78% had no comorbidities. MDRO colonisation was found in 8.7% (23 HWs). The following bacteria were found: S. maltophilia (n = 9; 3.4%) in inguinal swabs; methicillin-resistant Staphylococcus aureus (n = 8; 3%) from all sites; extended-spectrum ß-lactamase-producing bacteria (n = 5; 2%) in inguinal swabs; and vancomycin-resistant enterococci in an inguinal swab (n = 1; 0.4%). Previous antibiotic use was significantly associated with MDRO colonisation (OR 2.91, 95% CI 1.19–7.09, p = 0.018), mainly narrow spectrum oral beta-lactams and macrolides. S. malthophilia was polyclonal and human and environmental isolates differed. Conclusion: Colonisation by MRSA, VRE, and ESBL-producing bacteria was low; however, 4% were surprisingly colonized by polyclonal S. maltophilia. This pathogen may also suggest using narrow-spectrum rather than the expected broad-spectrum antimicrobials. Antibiotic use was the only risk factor found, mainly with oral narrow-spectrum drugs. [ABSTRACT FROM AUTHOR]

Previously, some bacteria were shown to harbour enzymes capable of catalysing the oxidative cleavage of the double bond of t -anethole and related compounds. The cofactor dependence of these enzymes remained enigmatic due to a lack of biochemical information. We report on catalytic and structural details of a representative of this group of oxidative enzymes: t -anethole oxygenase from Stenotrophomonas maltophilia (TAO Sm). The bacterial enzyme could be recombinantly expressed and purified, enabling a detailed biochemical study that has settled the dispute on its cofactor dependence. We have established that TAO Sm contains a tightly bound b-type heme and merely depends on dioxygen for catalysis. It was found to accept t -anethole, isoeugenol and O-methyl isoeugenol as substrates, all being converted into the corresponding aromatic aldehydes without the need of any cofactor regeneration. The elucidated crystal structure of TAO Sm has revealed that it contains a unique active site architecture that is conserved for this distinct class of heme-containing bacterial oxygenases. Similar to other hemoproteins, TAO Sm has a histidine (His121) as proximal ligand. Yet, unique for TAOs, an arginine (Arg89) is located at the distal axial position. Site directed mutagenesis confirmed crucial roles for these heme-liganding residues and other residues that form the substrate binding pocket. In conclusion, the results reported here reveal a new class of bacterial heme-containing oxygenases that can be used for the cleavage of alkene double bonds, analogous to ozonolysis in organic chemistry. • Identification of a new class of heme-containing enzymes. • Cofactor-independent biocatalytic C C cleavage. • Crystal structure of a trans-anethole oxygenase. • Novel active site architecture of a heme-containing enzyme. [ABSTRACT FROM AUTHOR]

Supercoiled flagellar filaments function as mechanical propellers within the bacterial flagellum complex, playing a crucial role in motility. Flagellin, the building block of the filament, features a conserved inner D0/D1 core domain across different bacterial species. In contrast, approximately half of the flagellins possess additional, highly divergent outer domain(s), suggesting varied functional potential. In this study, we report atomic structures of flagellar filaments from three distinct bacterial species: Cupriavidus gilardii, Stenotrophomonas maltophilia, and Geovibrio thiophilus. Our findings reveal that the flagella from the facultative anaerobic G. thiophilus possesses a significantly more negatively charged surface, potentially enabling adhesion to positively charged minerals. Furthermore, we analyze all AlphaFold predicted structures for annotated bacterial flagellins, categorizing the flagellin outer domains into 682 structural clusters. This classification provides insights into the prevalence and experimental verification of these outer domains. Remarkably, two of the flagellar structures reported herein belong to a distinct cluster, indicating additional opportunities on the study of the functional diversity of flagellar outer domains. Our findings underscore the complexity of bacterial flagellins and open up possibilities for future studies into their varied roles beyond motility. Here the authors use cryo-EM to determine the structures of three bacterial flagellar filaments, revealing distinct outer domains. Upon further analysis of all AlphaFold predicted flagellar outer domains, they show that the outer domains of flagella are highly diverse. [ABSTRACT FROM AUTHOR]

The spread of carbapenemase-producing gram-negative pathogens, especially those producing metallo-β-lactamases (MBLs), has become a major health concern. MBLs are molecularly the most diverse carbapenemases, produced by a wide spectrum of gram-negative organisms, including the Enterobacterales, Pseudomonas spp., Acinetobacter baumannii, and Stenotrophomonas maltophilia, and can hydrolyze most β-lactams using metal ion cofactors in their active sites. Over the years, the prevalence of MBL-carrying isolates has increased globally, particularly in Asia. MBL infections are associated with adverse clinical outcomes including longer length of hospital stay, ICU admission, and increased mortality across the globe. The optimal treatment for MBL infections not only depends on the pathogen but also on the underlying resistance mechanisms. Currently, there are only few drugs or drug combinations that can efficiently offset MBL-mediated resistance, which makes the treatment of MBL infections challenging. The rising concern of MBLs along with the limited treatment options has led to the need and development of drugs that are specifically targeted towards MBLs. This review discusses the prevalence of MBLs, their clinical impact, and the current treatment options for MBL infections and their limitations. Furthermore, this review will discuss agents currently in the pipeline for treatment of MBL infections. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to compare the safety and effectiveness of monotherapy versus combination therapy for the treatment of infections caused by S. maltophilia. Methods: This retrospective, multicenter, cohort study included patients treated with either monotherapy or combination therapy for infections caused by S. maltophilia. Primary outcomes included overall in-hospital mortality, 30-day mortality, and clinical cure. Safety outcomes were also evaluated. Multivariable logistic regression was used as a control for confounding variables. Results: A total of 407 patients were included, 330 patients received monotherapy and 77 patients received combination therapy. A total of 21% presented with concomitant bacteremia. After adjusting the differences between the two groups, there were no statistically significant differences between patients who received monotherapy versus combination therapy in clinical cure (55% vs 65%; OR, 0.72; 95% CI, 0.40–1.31) and overall in-hospital mortality (52% vs 49%; OR, 0.84; 95% CI, 0.45–1.57). However, patients who received monotherapy had a lower rate of 30-day mortality (28% vs 32%; OR, 0.45; 95% CI, 0.22–0.90) and acute kidney injury (9% vs 18%; OR, 0.35; 95% CI, 0.16–0.78). Conclusion: Clinical outcomes did not significantly differ in patients who received combination therapy versus monotherapy. More data are needed to validate these findings. [ABSTRACT FROM AUTHOR]

Sixteen isolates of bacteria obtained from the entomopathogenic nematode (Heterorhabditis sp.) infected cadavers of Galleria mellonella larvae were identified following phenotypic characterization and molecular analysis of 16S rRNA. Two isolates were identified as the symbiotic bacterium, Photothabdus luminescens, while 14 other isolates were represented by nine species of nonsymbiotic bacteria viz., Stenotrophomonas maltophilia, Alcaligenes aquatilis, Brevundimonas diminuta, Brucella pseudointermedia, Ochrobactrum sp., Brucella pseudogrignonensis, Brucella anthropic, Pseudomonas azatoformans and Pseudomonas lactis. The phylogenetic analysis confirmed the evolutionary relationship between P. luminescens and Pseudomonas spp. The study also found a close relationship among the nonsymbiotic bacteria such as A. aquatilis, B. diminuta, Ochrobactrum sp., and Brucella spp. P. luminescens has been documented for its insecticidal effects against a wide range of insects. The two local isolates obtained in this study may be explored for their biocontrol potential against major pests of the region. Further, the association of nonsymbiotic bacteria with the EPN may be investigated. [ABSTRACT FROM AUTHOR]

Antibiotics as micro-pollutants enter the environment through pharmaceutical effluents, human urine and faeces, and sweat and increase antibiotic resistance genes. The purpose of this study was to isolate amoxicillin (AMX) and co-amoxiclav (AMC) biodegrading bacteria from agricultural soil. From 15 isolates, Stenotrofomonas maltophilia strain DF1 (accession no. MW898434) was identified by phenotypic and molecular methods as the best degrading strain in the base mineral medium contained AMX or AMC. S. maltophilia strain DF1 was capable of removing 88.7% (w/v) of 43 ppm AMX and nearly 100% (w/v) of 15.2 ppm clavulanic acid after 72 h, which was measured by UV spectrophotometry and HPLC analysis. The maximum antibiotic biodegradation for S. maltophilia DF1 strain by one factor at a time was obtained after 72 h, without any additional carbon source, at 150 rpm shaking, the inoculum size of 5% (v/v), pH 7, and temperature 30 °C. According to the one-way ANOVA, the pH was affected on the AMX and AMC biodegradation. Optimal condition AMX and AMC biodegradation were determined by response surface method (RSM) with Design Expert12 software for three factors included inoculum level (1, 3, 5% (v/v)), pH (6.5, 7.25, and 8), and incubation time (40, 55, 70 h). Optimum degradation of AMC predicted by RSM at pH 7.12, inoculum level 4.78% (v/v), and 60.19 h. According to the results of this study, microbial degradation of AMX and AMC by S. maltophilia DF1 is a suitable strategy for the elimination of these micropollutants from aquatic media in aerobic conditions. [ABSTRACT FROM AUTHOR]

This study aimed to identify and characterize actinobacteria and rhizobia with plant growth-promoting (PGP) traits from chickpea plants. Out of 275 isolated bacteria, 25 actinobacteria and 5 chickpea rhizobia showed 1-aminocyclopropane-1-carboxylate deaminase (ACCd) activity. Selected chickpea rhizobia were tested for their nodulating capacity under sterile and non-sterile soil conditions. Further screening on salinity and PGP traits identified three promising isolates: Nocardiopsis alba KG13, Sinorhizobium meliloti KGCR17, and Bacillus safensis KGCR11. These three isolates were analyzed for their compatibility and made into a consortium (Consortium 1). This along with another consortium made from our salinity-tolerant lab strains Chryseobacterium indologenes ICKM4 and Stenotrophomonas maltophilia ICKM15 (Consortium 2) was compared in planta studies. Trials revealed that Consortium 2 showed significant (p < 0.05) tolerance and on above-ground, below-ground traits and yield components than Consortium 1. Moreover, both consortia induced nodulation in saline-stressed plants, alleviated electrolyte leakage (2.3 vs. 0.4 in ICCV 2; 1.8 vs. 0.6 in JG 11), and increased chlorophyll content. Histochemical staining indicated reduced oxidative stress and lipid peroxidation in consortium-treated plants under salinity stress. Further, gene expression studies revealed mixed patterns, with up-regulation of antioxidant and transporter genes observed in consortium-treated plants, particularly in Consortium 2. Overall, Consortium 2 showed better gene expression levels for antioxidant and transporter genes, indicating its superior efficacy in mitigating salinity stress in chickpea plants. This study provides valuable insights into the potential use of these microbial isolates in improving chickpea productivity by enhancing salinity tolerance. [ABSTRACT FROM AUTHOR]

Microorganisms are evolving to withstand the effect of antimicrobial agents and thereby pose a global threat known as antimicrobial resistance. Resistance towards multiple drugs due to various intrinsic as well environmental factors leads to an even more dangerous drug resistance property known as multi-drug resistance (MDR). WHO has recognized MDR bacteria as a top global threat as they complicate the treatment and augment mortality and morbidity risks. Gram-negative bacteria produce beta-lactamase enzymes that can hydrolyze beta-lactam antibiotics, impacting drug susceptibility. Stenotrophomonas maltophilia, an opportunistic pathogen, exemplifies MDR due to the production of two types of beta-lactamases. The metallo-beta-lactamase (MBL) L1 produced by the bacteria is a class B1 zinc-dependent MBL that is broadly substrate-specific and is a challenge to the currently available treatment options. This study constructs and analyzes a protein-protein interaction network of L1 beta-lactamase to comprehend its role in the MDR property of the bacteria. The network encompasses 51 proteins including L1 MBL (Smlt2667) and 382 interactions, revealing key players in MDR and potential drug targets. The network analysis aids the discernment of antimicrobial gene impact on cellular function, informing drug discovery strategies. This research addresses the emerging challenge of antibiotic resistance and identifies pathways for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Antibiotic resistance in bacteria leads to high mortality rates and healthcare costs, a significant concern for public health. A colonizer of the human respiratory system, Stenotrophomonas maltophilia is frequently associated with hospital-acquired infections in individuals with cystic fibrosis, cancer, and other chronic illnesses. The importance of this study is underscored by its capacity to meet the critical demand for effective preventive strategies against this pathogen, particularly among susceptible groups of cystic fibrosis and those undergoing cancer treatment. In this study, we engineered a multi-epitope vaccine targeting S. maltophilia through genomic analysis, reverse vaccination strategies, and immunoinformatic techniques by examining a total of 81 complete genomes of S. maltophilia strains. Our investigation revealed 1945 core protein-coding genes alongside their corresponding proteomic sequences, with 191 of these genes predicted to exhibit virulence characteristics. Out of the filtered proteins, three best antigenic proteins were selected for epitope prediction while seven epitopes each from CTL, HTL, and B cell were chosen for vaccine development. The vaccine was refined and validated, showing highly antigenic and desirable physicochemical features. Molecular docking assessments revealed stable binding with TLR-4. Molecular dynamic simulation demonstrated stable dynamics with minor alterations. The originality of this investigation is rooted in the thorough techniques aimed at designing a vaccine that directly targets S. maltophilia, a microorganism of considerable clinical relevance that currently lacks an available vaccine. This study not only responds to a pressing public health crisis but also lays the groundwork for subsequent research endeavors focused on the prevention of S. maltophilia outbreaks. Further evidence from studies in mice models is needed to confirm immune protection against S. maltophilia. [ABSTRACT FROM AUTHOR]

Oak decline is a major concern in Iran. A literature search with the terms 'Iran' AND 'oak' OR 'Quercus' from 1963 through 2023 resulted in 635 articles with over 200 dealing specifically with oak decline. In Iran, oak decline is most severe in the Zagros forests, followed by the Arasbaran and Hyrcanian forests. Of Iran's 11 native oak species, Quercus brantii is the most affected. Several factors have been identified as contributing to oak decline in Iran. Some economic and social factors include high rural unemployment, livestock overgrazing and uncontrolled cutting of live tree branches with the wood used for firewood and foliage used as food for farm animals. These pruning wounds can serve as entry points for pathogens and attract insects. Important abiotic factors included extended drought, increasing air temperature and wind speed, and increased levels of airborne dust and heavy metals. Important pathogens identified in the early 2000s included Armillaria mellea and charcoal rot fungus (Biscogniauxia mediterranea). More recently, many other fungal pathogens (e.g., Discula quercina, Neoscytalidium dimidiatum, Obolarina persica, Paecilomyces formosus and Phaeoacremonium tuscanicum) and bacterial pathogens (e.g., Bacillus pumilus, Brenneria goodwinii, Gibbsiella quercinecans, Rahnella victoriana and Stenotrophomonas maltophilia) were found in association with declining oaks. Among the insects, severe oak defoliation has resulted from various Lepidoptera in the families Erebidae, Geometridae and Tortricidae. Similarly, several bark‐ and wood‐boring beetles in the families Buprestidae and Cerambycidae were reported from declining oaks, with the buprestid Agrilus hastulifer being one of the most common. It is hoped that this review will improve our understanding of the many factors involved in oak decline in Iran and promote the development of management strategies. [ABSTRACT FROM AUTHOR]

Objectives Patients with reported Stenotrophomonas maltophilia (S. maltophilia) growth in lower respiratory tract samples were investigated. The results of these patients were assessed by clinicians as either infection or colonization. The data of patients considered to have S. maltophilia infection were compared to those considered to have colonization to explore factors associated with infection. Methods Parameters including as age, length of hospital stay, duration of S. maltophilia growth after hospital admission, sex, unit, department, specimen type, mechanical ventilation treatment status, antimicrobial susceptibility results, comorbidities, survival, and antimicrobials used during the period from hospital admission to S. maltophilia growth were investigated. Additionally, some biochemical parameters that were examined include the day of hospital admission, the day of sample collection when the bacterium was isolated (±1 day), and the day of discharge/died. Results The infection group had a significantly higher rate of admissions to internal medical departments and more cases of discharge/died. The infection group showed a lower amount of aminoglycoside antibiotic usage and significantly higher levels of BUN, creatinine, neutrophils, and neutrophil-to-lymphocyte ratio on their day of discharge/died. Conclusion Being admitted to internal medical departments and receiving aminoglycoside treatment were identified to be factors associated with S. maltophilia infection. These patients should be monitored for infection markers such as CRP and neutrophil count, as well as renal function tests. It should be noted that being infected with S. maltophilia is an independent risk factor for mortality. [ABSTRACT FROM AUTHOR]

Nucleases of the S1/P1 family have important applications in biotechnology and molecular biology. We have performed structural analyses of SmNuc1 nuclease from Stenotrophomonas maltophilia, including RNA cleavage product binding and mutagenesis in a newly discovered flexible Arg74‐motif, involved in substrate binding and product release and likely contributing to the high catalytic rate. The Arg74Gln mutation shifts substrate preference towards RNA. Purine nucleotide binding differs compared to pyrimidines, confirming the plasticity of the active site. The enzyme–product interactions indicate a gradual, stepwise product release. The activity of SmNuc1 towards c‐di‐GMP in crystal resulted in a distinguished complex with the emerging product 5′‐GMP. This enzyme from an opportunistic pathogen relies on specific architecture enabling high performance under broad conditions, attractive for biotechnologies. [ABSTRACT FROM AUTHOR]

Maximal standard-of-care (SOC) management could not stop the life-threatening progression of a necrotizing fasciitis induced by Panton-Valentine Leukocidin-producing Methicillin-Resistant Staphylococcus aureus (MRSA) in a 12-year-old boy. Multi-route phage therapy was initiated along with antibiotics against Staphylococcus aureus, Pseudomonas aeruginosa and Stenotrophomonas maltophilia, eventually leading to full recovery with no reported adverse events. [ABSTRACT FROM AUTHOR]

Background/Objectives: Intestinal colonization by multidrug-resistant (MDR) bacteria is considered one of the main risk factors for invasive infections in the hematopoietic stem-cell transplant (HSCT) setting, associated with hard-to-eradicate microorganisms. The aim of this study was to assess the rate of intestinal colonization by MDR bacteria and their microbial spectrum in a group of post-HSCT patients to study the genetic determinants of beta-lactam and glycopeptide resistance in the recovered isolates, as well as to determine the epidemiological relation between them. Methods: The intestinal colonization status of 74 patients admitted to the transplantation center of University Hospital "St. Marina"—Varna in the period January 2019 to December 2021 was investigated. Stool samples/rectal swabs were screened for third-generation cephalosporin and/or carbapenem-resistant Gram-negative bacteria, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and Stenotrophomonas maltophilia. Identification and antimicrobial susceptibility testing were performed by Phoenix (BD, Sparks, MD, USA) and MALDI Biotyper sirius (Bruker, Bremen, Germany). Molecular genetic methods (PCR, DNA sequencing) were used to study the mechanisms of beta-lactam and glycopeptide resistance in the collected isolates, as well as the epidemiological relationship between them. Results: A total of 28 patients (37.8%) were detected with intestinal colonization by MDR bacteria. Forty-eight non-duplicate MDR bacteria were isolated from their stool samples. Amongst them, the Gram-negative bacteria prevailed (68.8%), dominated by ESBL-producing Escherichia coli (30.3%), and followed by carbapenem-resistant Pseudomonas sp. (24.2%). The Gram-positive bacteria were represented exclusively by Enterococcus faecium (31.2%). The main beta-lactam resistance mechanisms were associated with CTX-M and VIM production. VanA was detected in all vancomycin-resistant enterococci. A clonal relationship was observed among Enterobacter cloacae complex and among E. faecium isolates. Conclusions: To the best of our knowledge, this is the first Bulgarian study that presents detailed information about the prevalence, resistance genetic determinants, and molecular epidemiology of MDR gut-colonizing bacteria in HSCT patients. [ABSTRACT FROM AUTHOR]

Abstract Background Stenotrophomonas maltophilia, a pathogen that colonizes medical equipment and causes nosocomial infections due to its ability to form biofilms, has high mortality rates. This study investigated the risk factors related to mortality in patients who were diagnosed with S. maltophilia bacteremia. Methods It is a multi-center, retrospective ad observational cohort study. The demographic characteristics, clinical findings, microbiological data, and risk factors for patients were obtained from the medical records of patients at ten different hospitals between January 1, 2018, and June 30, 2023. Results The study included a total of 321 patients. The observed thirty-day mortality rate was 46.1%. A central venous catheter (CVC) was present in 276 patients (86%), and in 66 of these patients (23.9%) the CVC was removed. While only 18 patients (5.6%) received appropriate empirical antibiotics, 242 (75.4%) patients received appropriate antibiotics according to antimicrobial susceptibility test (AST) results and treatment revisions. Multivariate analysis revealed that advanced age (hazard ratio [HR] = 1.02; 95% confidence interval [CI]: 1.00– 1.03), appropriate antibiotic treatment (HR = 0.35; 95% CI: 0.23–0.52), and removal of central venous catheters (HR = 0.31; 95% CI: 0.16–0.60) were significantly related to reduced mortality. Conclusions S. maltophilia is a significant pathogen, and to reduce its high mortality rate, removal of the CVC and switching to appropriate antibiotics should be performed as soon as possible.

Objectives: The World Health Organization named Stenotrophomonas maltophilia (SM) a critical multi-drug resistant threat, necessitating rapid diagnostic strategies. Traditional culturing methods require up to 96 h, including 72 h for bacterial growth, identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) through protein profile analysis, and 24 h for antibiotic susceptibility testing. In this study, we aimed at developing an artificial intelligence-clinical decision support system (AI-CDSS) by integrating MALDI-TOF MS and machine learning to quickly identify levofloxacin and trimethoprim/sulfamethoxazole resistance in SM, optimizing treatment decisions. Methods: We selected 8,662 SM from 165,299 MALDI-TOF MS-analysed bacterial specimens, collected from a major medical centre and four secondary hospitals. We exported mass-to-charge values and intensity spectral profiles from MALDI-TOF MS .mzML files to predict antibiotic susceptibility testing results, obtained with the VITEK-2 system using machine learning algorithms. We optimized the models with GridSearchCV and 5-fold cross-validation. Results: We identified distinct spectral differences between resistant and susceptible SM strains, demonstrating crucial resistance features. The machine learning models, including random forest, light-gradient boosting machine, and XGBoost, exhibited high accuracy. We established an AI-CDSS to offer healthcare professionals swift, data-driven advice on antibiotic use. Conclusions: MALDI-TOF MS and machine learning integration into an AI-CDSS significantly improved rapid SM resistance detection. This system reduced the identification time of resistant strains from 24 h to minutes after MALDI-TOF MS identification, providing timely and data-driven guidance. Combining MALDI-TOF MS with machine learning could enhance clinical decision-making and improve SM infection treatment outcomes.

Background: Trimethoprim-sulfamethoxazole (TMP-SMX) has long been considered the treatment of choice for infections caused by Stenotrophomonas maltophilia. Levofloxacin has emerged as a potential option for treating these infections. This study aimed to evaluate the clinical outcomes in patients who received TMP-SMX versus levofloxacin for treating S. maltophilia infections. Methods: A retrospective, cohort study was conducted in 4 tertiary centres and included patients who were treated with either TMP-SMX or levofloxacin for infections caused by S. maltophilia. The main study outcomes were overall in-hospital mortality, 30-d mortality, and clinical cure. Safety outcomes were also evaluated. Multivariate analysis using logistic regression was used to control for the effect of the covariables. Results: We included 371 patients in this study, 316 received TMP-SMX and 55 patients received levofloxacin. A total of 70% were in the intensive care unit and 21% presented with bacteraemia. No statistically significant differences were observed in overall in-hospital mortality (52% vs. 40%; P = 0.113; odd ratio [OR], 1.59; 95% confidence interval [CI], 0.89–2.86), 30-d mortality (28% vs. 25%; P = 0.712; OR, 1.13; 95% CI, 0.59–2.18), or clinical cure (55% vs. 64%; P = 0.237; OR, 0.70; 95% CI, 0.37–1.31). Rates of acute kidney injury were comparable between the two groups (11% vs. 7%; P = 0.413). Conclusion: Patients receiving levofloxacin for the treatment of infections caused by S. maltophilia demonstrated clinical outcomes similar to those receiving TMP-SMX. Our study suggests that levofloxacin can be a reasonable alternative to TMP-SMX to treat these infections.

Stenotrophomonas maltophilia causes challenging infections in immunocompromised patients, exhibiting increasing resistance to multiple antimicrobials and possessing various virulence genes, including emerging resistance to trimethoprim‐sulfamethoxazole. A total of 80 clinical isolates of S. maltophilia were collected from multiple hospitals in Tehran, Iran. This study conducted an analysis of antibiotic susceptibility by disc diffusion method and E‐test assay, resistance and virulence gene frequencies were examined by PCR‐sequencing, and multilocus sequencing typing (MLST) was performed for strain typing. Across the tested isolates, we observed notably high resistance rates for imipenem 80 (100%), meropenem 78(97.5%), and ceftazidime 72 (90%), while trimethoprim‐sulfamethoxazole (SXT) showed a lower resistance rate of 2 (2.5%). Minocycline and levofloxacin demonstrated the highest susceptibility rates, with 70 (87.5%) and 80 (100%), respectively. The prevalence of antibiotic resistance genes blaL1, and blaL2 was 71 (88.75%) and 76 (95%), respectively. Additionally, the PCR analysis revealed that the frequency of virulence genes (fliC, virB, papD, pilU, hlyIII, stmPr1, and stmPr2) was 78 (97.5%), 77 (96.25%), 58 (72.5%), 77 (96.2%), 76 (95%), 31 (38.75%), and 80 (100%), respectively. Resistance to SXT isolate belong to the sequence type (ST15) and exhibits allelic profiles of (10, 29, 21, 21, 32, 32, and 10). The data obtained from our investigation have indicated that SXT remains an efficacious antibiotic and also highlighted the importance of effective management, identification of resistant isolates, and typing methods to address the global prevalence of antibiotic resistance in S. maltophilia. [ABSTRACT FROM AUTHOR]

The existence of viable human pathogens in bioaerosols which can cause infection or affect human health has been the subject of little research. In this study, data provided by 10 tropospheric aircraft surveys over Japan in 2014 confirm the existence of a vast diversity of microbial species up to 3,000 m height, which can be dispersed above the planetary boundary layer over distances of up to 2,000 km, thanks to strong winds from an area covered with massive cereal croplands in Northeast (NE) Asia. Microbes attached to aerosols reveal the presence of diverse bacterial and fungal taxa, including potential human pathogens, originating from sewage, pesticides, or fertilizers. Over 266 different fungal and 305 bacterial genera appeared in the 10 aircraft transects. Actinobacteria, Bacillota, Proteobacteria, and Bacteroidetes phyla dominated the bacteria composition and, for fungi, Ascomycota prevailed over Basidiomycota. Among the pathogenic species identified, human pathogens include bacteria such as Escherichia coli, Serratia marcescens, Prevotella melaninogenica, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus saprophyticus, Cutibacterium acnes, Clostridium difficile, Clostridium botulinum, Stenotrophomonas maltophilia, Shigella sonnei, Haemophillus parainfluenzae and Acinetobacter baumannii and health-relevant fungi such as Malassezia restricta, Malassezia globosa, Candida parapsilosis and Candida zeylanoides, Sarocladium kiliense, Cladosporium halotolerans, and Cladosporium herbarum. Diversity estimates were similar at heights and surface when entrainment of air from high altitudes occurred. Natural antimicrobial-resistant bacteria (ARB) cultured from air samples were found indicating long-distance spread of ARB and microbial viability. This would represent a novel way to disperse both viable human pathogens and resistance genes among distant geographical regions. [ABSTRACT FROM AUTHOR]

The body temperature of Warm-blooded hosts impedes and informs responses of bacteria accustomed to cooler environments. The second messenger c-di-GMP modulates bacterial behavior in response to diverse, yet largely undiscovered, stimuli. A long-standing debate persists regarding whether a local or a global c-di-GMP pool plays a critical role. Our research on a Stenotrophomonas maltophilia strain thriving at around 28°C, showcases BtsD as a thermosensor, diguanylate cyclase, and effector. It detects 37°C and diminishes c-di-GMP synthesis, resulting in a responsive sequence: the periplasmic c-di-GMP level is decreased, the N-terminal region of BtsD disengages from c-di-GMP, activates the two-component signal transduction system BtsKR, and amplifies sod1-3 transcription, thereby strengthening the bacterium′s pathogenicity and adaptation during infections in 37°C warm Galleria mellonella larvae. This revelation of a single-protein c-di-GMP module introduces unrecognized dimensions to the functional and structural paradigms of c-di-GMP modules and reshapes our understanding of bacterial adaptation and pathogenicity in hosts with a body temperature around 37°C. Furthermore, the discovery of a periplasmic c-di-GMP pool governing BtsD-BtsK interactions supports the critical role of a local c-di-GMP pool. Author summary: The body temperature of mammals, typically around 37°C, serves as an important host-derived signal for pathogens thriving at substantially lower temperatures. The ability to detect and respond to this host-derived temperature signal is essential for a bacterium′s life cycle shift from a free-living state to pathogenicity. The c-di-GMP signaling network is predominant in detecting signals and regulating bacterial behaviors, leaving many input signals and their sensing mechanisms remain elusive. The significance of our research lies in uncovering the mechanism by which a single-protein c-di-GMP module detects 37°C and enhances the virulence and adaptability of Stenotrophomonas maltophilia during infection, broadening our understanding of the role played by a compartmentalized c-di-GMP pool and our knowledge of the simplicity of c-di-GMP modules. This breakthrough deepens our insight into how this bacterium transforms between free-living state and pathogenicity at 37°C, and opens new avenues for developing treatments targeting this pathway. [ABSTRACT FROM AUTHOR]

Background: Biofilm production in nonfermenting Gram-negative bacteria influences drug resistance. The aim of this work was to evaluate the effect of different antibiotics on biofilm eradication of clinical isolates of Achromobacter, Burkholderia, and Stenotrophomonas maltophilia. Methods: Clinical isolates were identified by matrix-assisted laser desorption ionization–time of flight mass spectrometry in a third-level hospital in Monterrey, Mexico. Crystal violet staining was used to determine biofilm production. Drug susceptibility testing was determined by broth microdilution in planktonic cells and biofilm cells. Results: Resistance in planktonic cells was moderate to trimethoprim-sulfamethoxazole, and low to chloramphenicol, minocycline, levofloxacin (S. maltophilia and Burkholderia), ceftazidime, and meropenem (Burkholderia and Achromobacter). Biofilm eradication required higher drug concentrations of ceftazidime, chloramphenicol, levofloxacin, and trimethoprim-sulfamethoxazole than planktonic cells (p < 0.05). Levofloxacin showed biofilm eradication activity in S. maltophilia, minocycline and meropenem in Burkholderia, and meropenem in Achromobacter. Conclusions: Drug resistance increased due to biofilm production for some antibiotics, particularly ceftazidime and trimethoprim-sulfamethoxazole for all three pathogens, chloramphenicol for S. maltophilia and Burkholderia, and levofloxacin for Burkholderia. Some antibiotics could be used for the treatment of biofilm-associated infections in our population, such as levofloxacin for S. maltophilia, minocycline and meropenem for Burkholderia, and meropenem for Achromobacter. [ABSTRACT FROM AUTHOR]

Introduction The material of a bandage plays an important role in wound management. Microorganisms can colonize the dressing and release toxins, which create dead cells in the wound. This allows the microorganisms to bind the dead cells and infect the wound. Thus, a dressing is needed that kills bacteria in the bandage. To combat health care–associated infections, antimicrobial treatment of medical textiles, such as gauze, uniforms, curtains, bed sheets, gowns, and masks, is required. Besides, antimicrobial resistance is another major problem of this century. Antibacterial overuse has contributed to drug-resistant bacteria. To combat these two problems, we synthesized new organo-selenium compounds that can be attached to the cotton of the dressing. We then used an in vivo wound model, which allowed us to measure the effectiveness of selenium attached to a cotton dressing, to prevent bacteria from infecting a wound. Materials and Methods Organo-selenium was attached to cotton fabric, resulting in a fabric with 0.1% selenium covalently attached to it. Staphylococcus aureus (as well as methicillin-resistant S. aureus [MRSA]), Stenotrophomonas maltophilia , Enterococcus faecalis , Staphylococcus epidermidis , and Pseudomonas aeruginosa were chosen for the wound infection study. All the bacteria were enumerated in the wound dressing and in the wound tissue under the dressing. Wounds were made on the backs of mice. The material was used as a bandage over the wound. Bacteria were injected into the wound under the bandage. The amount of bacteria in the wound after 5 days was determined. A similar study was performed using dressing material that was soaked in phosphate buffered saline at 37 °C for 3 months before use. Results Cotton dressing with selenium attached showed complete inhibition (7 logs, as compared with control dressing) of different bacterial strains, in both the dressing and "the tissue" of the wound. Similar results were obtained using selenium cotton dressing that was soaked for 3 months before use. Control cotton with no selenium showed complete infiltration of bacteria into the wound and the dressing. In addition, a study was performed under Food and Drug Administration standard methods to show the ability of the selenium to kill bacteria in the fabric, using material that was washed 5 times in detergent. This also showed complete killing of bacteria in the fabric. Conclusions The results show that the selenium remains in the dressing after washing and is able to completely protect the wound from bacterial infection. In the selenium bandage, no bacteria were found in the bandage or the wound after 5 days. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia (S. maltophilia) is a spoilage microorganism widely distributed in vegetables, dairy products, and various environments and can cause serious foodborne illnesses. Renowned for its environmentally friendly, safe, and non-toxic properties, rose essential oil (REO) is widely recognized as an exceptional natural antibacterial agent. In the present study, we conducted a comprehensive analysis to elucidate the inhibition mechanism of REO against S. maltophilia at both cellular and metabolic levels. The results demonstrated that REO treatment of cells resulted in the disruption of cell structure and leakage of cellular contents. Remarkable changes in the morphology of bacterial cells were observed under both scanning electron microscopy and transmission electron microscopy. At the metabolic level, multiple metabolic pathways were disrupted after REO treatment, including amino acid metabolism, nucleotide metabolism, and aminoacyl tRNA biosynthesis. These results shed new light to the inhibition mechanism of REO against S. maltophilia and provide a theoretical basis for the development of effective essential oil preservatives. [ABSTRACT FROM AUTHOR]

Colombia shows a high density and variety of bird species, making it one of the most diverse avian territories globally. Antioquia ranks among the top four provinces with the greatest variety of bird species, underscoring the importance of research efforts on the local bird fauna. Therefore, this study aimed to identify bacterial agents in the blood of wild birds from the municipality of Jardín (Antioquia, Colombia) by 16S qPCR sequencing. A descriptive cross-sectional study was conducted using non-probabilistic convenience sampling. Wild birds were captured using mist nets and blood samples were collected from each animal via puncture using sterile lancets in the brachial vein, and a drop of blood was collected on filter paper for qPCR analysis. The 16S gene in bacterial genomes was found in 13 out of 46 wild birds of the Passeriform and quasi-Passeriform orders, captured at three different locations within the study municipality at altitudes ranging from 1,665 to 2,034 m.a.s.l. Seven different bird species were recorded and four different haemobacteria were identified (i.e. Exiguobacterium spp., Escherichia coli, Stenotrophomonas spp., and Stenotrophomonas maltophilia). This study contributes to the knowledge in Colombia by identifying four different hemobacteria in wild birds. Further research is required on the health status of these birds and the attributable impacts on their populations and other related factors, including humans. [ABSTRACT FROM AUTHOR]

17 β‐Estradiol is produced by animals, and humans and excreted through excreta, and has endocrine‐disrupting activity. Bacterial degradation is one of the suitable methods used for the removal of 17 β‐estradiol (E2) from the natural environment. In this study, E2‐degrading bacteria were screened from the enriched sediment sample from the wastewater environment. Two bacterial strains of E2‐degrading bacteria (Stenotrophomonas maltophilia MN08 and Pseudomonas aeruginosa KL10) were determined and >70% of E2‐degradation was achieved. The strain MN08 could rapidly remove approximately 86.5% ± 1.3% of E2 within 7 days of treatment. In addition, the strain KL10 removed 79.5% ± 1% of E2 within the same period. Optimized culture temperature and pH of the medium could improve E2‐degradation. The results demonstrated that the strain MN08 exhibited maximum E2‐degradation activity at 35°C, and pH 8.0. The optimal pH for strain KL10 to degrade E2 ranged from 7.0 to 9.0. The E2‐degradation level for the mixture culture systems can exhibit synergistic E2‐degradation activity. The degradation of the MN08 and KL10 individual strains was 87.3% ± 1.2% and 81.4% ± 1.5%, respectively. The E2‐degradation potential for the mixed culture system was 91.3% ± 2.9% under optimized conditions in which 100 mg/L of E2 served as the sole source of carbon and energy. The present finding demonstrates that the co‐culture of S. maltophilia MN08 and P. aeruginosa KL10 may provide a promising bio‐treatment strategy for the removal of steroids from wastewater. [ABSTRACT FROM AUTHOR]

Using existing adrentimicrobials with essential oil components to prevent antimicrobial resistance is an alternative strategy. This study aimed to evaluate the resistance status, synergistic combinations, and in vitro biofilm formation activities of clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA), Stenotrophomonas maltophilia and Candida albicans against antimicrobial agents and cinnamaldehyde, carvacrol, eugenol, limonene and eucalyptol. Antimicrobial activities were evaluated by microdilution, cytotoxicity by XTT, synergy by checkerboard and time-kill, and biofilm inhibition by microplate methods. Cinnamaldehyde and carvacrol showed strong antimicrobial activity. Synergistic effects were observed when using all essential oils with antimicrobials. Only two C. albicans isolates showed antagonism with cinnamaldehyde and fluconazole. The constituents showed cytotoxic effects in the L929 cell line (except limonene). A time-kill analysis revealed a bacteriostatic effect on S. maltophilia and MRSA isolates and a fungicidal effect on C. albicans isolates. These results are important for further research to improve antimicrobial efficacy or to develop new agents. [ABSTRACT FROM AUTHOR]

The aim of this work was to assess the microbiological safety and quality of horsemeat. A total of 19 fresh horsemeat samples were analysed. Mesophile counts were 4.89 ± 1.08 log CFU/g, and Enterobacteriaceae, Staphylococcus spp., and enterococci were only isolated from 36.84%, 21.05%, and 15.79% of the samples, respectively. Neither Staphylococcus aureus nor Escherichia coli were found in any sample. Listeria spp. and Listeria monocytogenes were detected in 31.58% and 21.05% of the samples, respectively. Campylobacter jejuni was not detected in any sample. The dominant bacteria were lactic acid bacteria. Seven different Staphylococcus spp. were identified, the most common being S. delphini, S. saprophyticus, and S. warneri. S. delphini showed resistance against mupirocin and cefoxitin. All the L. monocytogenes strains showed resistance against ampicillin, cefotaxime, and oxacillin. Multi-resistant Yersinia enterocolitica, Stenotrophomonas maltophilia, and Vagococcus. fluvialis strains were found, with resistance to 11, 7, and 8 antibiotics, respectively, causing significant concern. Therefore, specific actions should be taken to decrease the contamination of horsemeat. [ABSTRACT FROM AUTHOR]

The exploration of microbial genetic resources for the production of fFen-flavor Baijiu has not only enriched the microbial library for baijiu production but has also laid the foundation for process improvement and strain optimization in baijiu brewing. In this study, a total of 177 fungal isolates were screened, including Saccharomyces cerevisiae, non-Saccharomyces cerevisiae, molds, and some pathogenic bacteria. Among them, Saccharomyces cerevisiae was the most abundant with 119 isolates, playing a major role in the fermentation of baijiu production. A total of 148 bacterial isolates were obtained from the fermentation mash samples, showing greater diversity compared to fungi. Bacillus species were the most abundant, with 94 isolates. Bacillus licheniformis, in particular, can produce a rich enzymatic system and flavor precursors, making it an important contributor to the sensory quality of baijiu. Lactic acid bacteria were the second most abundant, with 16 isolates. Additionally, five pathogenic fungal species were identified, including Candida pelliculosa, Candida lusitaniae, Fusarium oxysporum, Fusarium solani and Talaromyces marneffei. Six pathogenic bacterial species were also isolated, namely Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus xylosus, Moraxella osloensis, Actinomyces meyeri and Stenotrophomonas maltophilia. Finally, two strains of high acetate ethyl ester-producing yeast and lactate-degrading bacteria with good tolerance to temperature, pH, and ethanol concentration were identified as Saccharomyces cerevisiae and Bacillus licheniformis, respectively. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia, a ubiquitous environmental bacterium, is an important cause of nosocomial infections. Although banned in some countries, paraquat (PQ) is commonly used to control weeds. In this study, we investigated the effects of increasing concentrations of PQ on S. maltophilia and its antimicrobial resistance. The sequential exposure of S. maltophilia K279a to increasing concentrations of PQ induces the formation of strains with increased resistance to PQ. Among the 400 PQ-resistant isolates tested, 70 clones were resistant to 16 μg/ml ciprofloxacin (CIP), and around 18% of the PQ/CIP-resistant isolates showed increased resistance to all the tested antimicrobials including, the aminoglycosides, quinolones, cephalosporin, chloramphenicol, and co-trimoxazole. The results of the expression analysis of the antimicrobial resistance genes in the five selected PQ/CIP-resistant isolates demonstrated the high expression of genes encoding efflux pumps (smeYZ, smaAB, smaCDEF, smeDEF, smeVWX, and smtcrA) and the enzymes aph(3')-IIc, blaL1, and blaL2. However, expression of the genes known for PQ resistance (i.e., mfsA and sod) were not altered relative to the wild-type levels. Whole genome sequence analysis identified gene mutations that could account for the antimicrobial resistance, namely, smeT (TetR family regulatory protein), rplA (ribosomal protein L1), and acnA (aconitase A). Ectopic expression of wild-type AcnA partially complemented the fluoroquinolone-resistant phenotype of the mutant with mutated acnA, which suggests the role of aconitase A in antimicrobial susceptibility. Exposure of S. maltophilia to PQ thus induces the development of strains that increase resistance to multiple antimicrobials. [ABSTRACT FROM AUTHOR]

Background Lysins (cell wall hydrolases) targeting gram-negative organisms require engineering to permeabilize the outer membrane and access subjacent peptidoglycan to facilitate killing. In the current study, the potential clinical utility for the engineered lysin CF-370 was examined in vitro and in vivo against gram-negative pathogens important in human infections. Methods Minimum inhibitory concentration (MICs) and bactericidal activity were determined using standard methods. An in vivo proof-of-concept efficacy study was conducted using a rabbit acute pneumonia model caused by Pseudomonas aeruginosa. Results CF-370 exhibited potent antimicrobial activity, with MIC50/90 values (in µg/mL) for: P aeruginosa , 1/2; Acinetobacter baumannii , 1/1; Escherichia coli , 0.25/1; Klebsiella pneumoniae , 2/4; Enterobacter cloacae 1/4; and Stenotrophomonas maltophilia 2/8. CF-370 furthermore demonstrated bactericidal activity, activity in serum, a low propensity for resistance, anti-biofilm activity, and synergy with antibiotics. In the pneumonia model, CF-370 alone decreased bacterial densities in lungs, kidneys, and spleen versus vehicle control, and demonstrated significantly increased efficacy when combined with meropenem (vs either agent alone). Conclusions CF-370 is the first engineered lysin described with potent broad-spectrum in vitro activity against multiple clinically relevant gram-negative pathogens, as well as potent in vivo efficacy in an animal model of severe invasive multisystem infection. [ABSTRACT FROM AUTHOR]

Background: Bloodstream infections (BSI) are a significant health concern, necessitating effective diagnostic tools. This study evaluates the performance of the BD Bactec FX system in comparison to the established BacT/Alert system, examining mean time till detection (TTD) across various blood culture bottles. Methods: The study involves 148 blood culture bottles, inoculated with representative bacterial ATCC strains (n= 15) and 04 yeast isolates. Parallel testing is conducted by seeding 10-30 colony-forming units (CFU) in duplicate in both BD Bactec FX and BacT/Alert systems. TTD is assessed across aerobic, anaerobic, and pediatric bottles for diverse microbial species. Results: All 148 bottles tested in parallel show positive signals in both systems. BD Bactec FX demonstrates significantly shorter TTD for adult-seeded cultures in aerobic and anaerobic bottles compared to BacT/Alert Similarly, pediatric bottles with BD Bactec FX exhibit a shorter TTD compared to BacT/Alert. The statistical significance of TTD, 95% confidence intervals (CI), and p-values is evident for Bactec FX aerobic, anaerobic, and pediatric bottles across tested organisms. Notable examples of faster TTD include; Bacteroides ovatus (16.6h by Bactec FX vs. 70.5h by Bact/Alert 3D), Stenotrophomonas maltophilia (33.7h vs. 72.5h), and Streptococcus pyogenes (8.1h vs. 11.9h). Conclusions: In conclusion, the study's findings demonstrate that BD Bactec FX surpasses BacT/Alert in prompt microbial detection, showcasing potential for early identification of bacteremia and fungemia. Faster TTD implies the potential to initiate timely antimicrobial treatment, thereby reducing patient morbidity and mortality. However, exceptions in certain microbial species highlight the need for comprehensive clinical validation to establish the broad applicability of these findings. [ABSTRACT FROM AUTHOR]

Background Stenotrophomonas maltophilia is a carbapenem-resistant Gram-negative pathogen increasingly responsible for difficult-to-treat nosocomial infections. Objectives To describe the contemporary clinical characteristics and genome epidemiology of patients colonized or infected by S. maltophilia in a multicentre, prospective cohort. Methods All patients with a clinical culture growing S. maltophilia were enrolled at six tertiary hospitals across Japan between April 2019 and March 2022. The clinical characteristics, outcomes, antimicrobial susceptibility and genomic epidemiology of cases with S. maltophilia were investigated. Results In total, 78 patients were included representing 34 infection and 44 colonization cases. The median age was 72.5 years (IQR, 61–78), and males accounted for 53 cases (68%). The most common comorbidity was localized solid malignancy (39%). Nearly half of the patients (44%) were immunosuppressed, with antineoplastic chemotherapy accounting for 31%. The respiratory tract was the most common site of colonization (86%), whereas bacteraemia accounted for most infection cases (56%). The 30 day all-cause mortality rate was 21%, which was significantly higher in infection cases than colonization cases (35% versus 9%; adjusted HR, 3.81; 95% CI, 1.22–11.96). Susceptibility rates to ceftazidime, levofloxacin, minocycline and sulfamethoxazole/trimethoprim were 14%, 65%, 87% and 100%, respectively. The percentage of infection ranged from 13% in the unclassified group to 86% in genomic group 6A. The percentage of non-susceptibility to ceftazidime ranged from 33% in genomic group C to 100% in genomic groups 6 and 7 and genomic group geniculate. Conclusions In this contemporary multicentre cohort, S. maltophilia primarily colonized the respiratory tract, whereas patients with bacteraemia had the highest the mortality from this pathogen. Sulfamethoxazole/trimethoprim remained consistently active, but susceptibility to levofloxacin was relatively low. The proportions of cases representing infection and susceptibility to ceftazidime differed significantly based on genomic groups. [ABSTRACT FROM AUTHOR]

This study aims to understand the role of Stenotrophomonas maltophilia AVSW 1, a chilli root endophytic bacteria, in promoting plant growth and fungal antagonism against Fusarium oxysporum in tomato. Ability of AVSW1 in terms of fungal antagonism, SEM analysis of root colonization, growth optimization and enhancement of the production of Indole-3-aceticacid, Ammonia and siderophore, and phosphate solubilisation followed by in vitro plant growth promotion of tomato using seed bacterization were evaluated. using GC-MS and HPLC analysis of volatile compounds and secondary metabolites of AVSW1was also studied. AVSW1 showed 26.3μg/ml of Ammonia production, 19.33 μg of IAA production, 60.67 psu of Siderophore and 91.67ppm of phosphate solubilisation under optimised growth conditions(35°C, pH7,1% NaCl,1% Fructose, 1% Peptone and 60 h incubation). Growth parameters like root length, shoot height, no. of leaves and lateral roots, biomass, and protein and carbohydrate are much higher in AVSW 1 inoculated plants compared to untreated control. GC-MS analysis revealed that 2-Pentanone,4-Hydroxy-4-methyl, Cyclopropane,1-(1-Methylethyl)-2-Nonyl-Glycine, N-Acetyl-N(Trifluoroacetyl), MethylEster2-Acetoxy Isobutyryl Chloride, propanoic Acid, 2-Oxo-, Methyl Ester Pentanoic Acid 4-Oxo,5-Hydroxy pentane hydroxyl amine Ethanol,2-(Octyloxy), 2-Cyclopenten-1-One, 2-Hydroxy-3,4-Dimethyl and 2, 2- Di methyl tetrahydro pyran-4-ol are pivotal compounds of S. maltophilia AVSW1 responsible for fungal antibiosis and root colonization to promote growth in tomato seedlings. [ABSTRACT FROM AUTHOR]

This retrospective study was conducted to evaluate the characteristics and outcomes of patients with ventilator-associated pneumonia (VAP) caused by Stenotrophomonas maltophilia (S. maltophilia), focusing on the impact of appropriate empirical antimicrobial treatment. Of the enrolled 240 patients with VAP due to S. maltophilia (median age: 45 years) in a tertiary-care hospital in southern Thailand between January 2010 and December 2021, 90% had medical comorbidities and 91% had previously received carbapenems. In addition, only 45% of the patients were initially admitted to the intensive care unit. Patients administered appropriate empirical antimicrobial treatment including colistin alone and colistin plus TMP-SMX or fluoroquinolone-based regimens had significantly lower 14-day, 30-day, and in-hospital mortalities, compared with those who did not receive appropriate empirical antimicrobial treatment (21% and 2% vs. 31%; 30% and 5% vs. 44%; and 30% and 12% vs. 53%, respectively). Thus, the use of appropriate empirical antimicrobial treatments led to a significantly reduced length of hospital stay, duration of ventilation, and hospital costs. The current study suggests that the use of appropriate empirical antimicrobial treatment based on susceptibility testing without considering pharmacokinetic properties and administration dosages improves the outcomes of patients with VAP due to S. maltophilia. [ABSTRACT FROM AUTHOR]

Removing polychlorinated biphenyls (PCBs) from the environment is an important process for the protection of biota. This work examines three different approaches to the degradation of such contaminants. The first involves the use of iron bionanoparticles (Fe-BNPs) prepared through green synthesis from selected plant matrices. The second approach entails the use of the bacteria Stenotrophomonas maltophilia (SM) and Ochrobactrum anthropi (OA) isolated from a PCB-contaminated area, Strážsky canal, located in the Slovak republic, which receives efflux of canal from Chemko Strážske plant, a former producer of PCB mixtures. The third approach combines these two methods, employing a sequential hybrid two-step application of Fe-BNPs from the plant matrix followed by the application of bacterial strains. Fe-BNPs are intended to be an eco-friendly alternative to synthetic nanoscale zero-valent iron (nZVI), which is commonly used in many environmental applications. This work also addresses the optimization parameters for using nZVI in PCB degradation, including the pH of the reaction, oxygen requirements, and dosage of nZVI. Pure standards of polyphenols (gallic acid, GA) and flavonoids (quercetin, Q) were tested to produce Fe-BNPs using green synthesis at different concentrations (0.1, 0.3, 0.5, 0.8, and 1 g.L−1) and were subsequently applied to the PCB degradation experiments. This step monitored the minimum content of bioactive substances needed for the synthesis of Fe-BNPs and their degradation effects. Experimental analysis indicated that among the selected approaches, sequential nanobiodegradation appears to be the most effective for PCB degradation, specifically the combination of Fe-BNPs from sage and bacteria SM (75% degradation of PCBs) and Fe-BNPs from GA (0.3 g.L−1) with bacteria OA (92% degradation of PCBs). [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia (S. maltophilia) is an emerging opportunistic pathogen that exhibits resistant to a majority of commonly used antibiotics. Phages have the potential to serve as an alternative treatment for S. maltophilia infections. In this study, a lytic phage, A1432, infecting S. maltophilia YCR3A-1, was isolated and characterized from a karst cave. Transmission electron microscopy revealed that phage A1432 possesses an icosahedral head and a shorter tail. Phage A1432 demonstrated a narrow host range, with an optimal multiplicity of infection of 0.1. The one-step growth curve indicated a latent time of 10  min, a lysis period of 90  min, a burst size of 43.2 plaque-forming units per cell. In vitro bacteriolytic activity test showed that phage A1432 was capable to inhibit the growth of S. maltophilia YCR3A-1 in an MOI-dependent manner after 2  h of co-culture. BLASTn analysis showed that phage A1432 genome shares the highest similarity (81.46%) with Xanthomonas phage Xoo-sp2 in the NCBI database, while the query coverage was only 37%. The phage contains double-stranded DNA with a genome length of 61,660  bp and a GC content of 61.92%. It is predicted to have 79 open reading frames and one tRNA, with no virulence or antibiotic resistance genes. Phylogenetic analysis using terminase large subunit and DNA polymerase indicated that phage A1432 clustered with members of the Bradleyvirinae subfamily but diverged into a distinct branch. Further phylogenetic comparison analysis using Average Nucleotide Identity, proteomic phylogenetic analysis, genomic network analysis confirmed that phage A1432 belongs to a novel genus within the Bradleyvirinae subfamily, Mesyanzhinovviridae family. Additionally, phylogenetic analysis of the so far isolated S. maltophilia phages revealed significant genetic diversity among these phages. The results of this research will contribute valuable information for further studies on their morphological and genetic diversity, will aid in elucidating the evolutionary mechanisms that give rise to them. [ABSTRACT FROM AUTHOR]

The screening and identification of attachment genes is important to exploring the formation mechanism of biofilms at the gene level. It is helpful to the development of key culture technologies for aerobic granular sludge (AGS). In this study, genome-wide sequencing and gene editing were employed for the first time to investigate the effects and functions of attachment genes in AGS. With the help of whole-genome analysis, ten attachment genes were screened from thirteen genes, and the efficiency of gene screening was greatly improved. Then, two attachment genes were selected as examples to further confirm the gene functions by constructing gene-knockout recombinant mutants of Stenotrophomonas maltophilia ; when the two attachment genes were knocked out, the attachment potential was reduced by 50.67% and 43.93%, respectively. The results provide a new theoretical principle and efficient method for the development of AGS from the perspective of attachment genes. [Display omitted] [ABSTRACT FROM AUTHOR]

Key Clinical Message: Stenotrophomonas maltophilia can cause rare odontogenic brain abscesses in immunocompetent patients, highlighting the importance of considering uncommon pathogens in central nervous system infections. With only three reported cases of cerebral abscesses and one pituitary abscess caused by this microorganism, tailored diagnostic methods and individualized treatment regimens are crucial for accurate management. Brain abscesses present diagnostic and therapeutic challenges, with Stenotrophomonas maltophilia infections being exceptionally rare in the central nervous system. We present a case of odontogenic brain abscesses caused by S. maltophilia in an immunocompetent patient, highlighting the rarity and complexity of such infections. A 66‐year‐old male presented with spatial–temporal disorientation and left‐sided weakness. Radiological investigations revealed an expansive lesion in the right posterior frontal region. A craniotomy and drainage were performed, identifying S. maltophilia in the purulent material. The patient responded well to tailored antibiotic therapy. S. maltophilia‐related central nervous system infections are infrequent, emphasizing the need for a heightened clinical suspicion in atypical cases. This case contributes to the literature, emphasizing the importance of a multidisciplinary approach for successful diagnosis and management. [ABSTRACT FROM AUTHOR]

Background: Stenotrophomonas maltophilia is an opportunistic, gram-negative bacillus with few therapeutic options due to a high level of intrinsic resistance. Trimethoprim/sulfamethoxazole (SXT) is recommended as the first-line treatment; however, minocycline (MIN) has been shown to have similar clinical outcomes in treating S. maltophilia and addresses concern for increasing resistance to SXT. Objective: The objective of this study is to evaluate the efficacy and safety outcomes of nonurinary, monomicrobial infections due to S. maltophilia in hospitalized patients treated with MIN or SXT. Methods: This was a retrospective study of hospitalized adult patients receiving MIN or SXT for nonurinary monomicrobial S. maltophilia infection from April 1, 2018 to March 31, 2020. The primary outcome was clinical disposition classified as rates of clinical failure, clinical improvement, or clinical success. Results: Eighty-two patients (88.2%) received MIN and 11 patients (11.8%) received SXT initially. Clinical failure occurred in 16 (19.5%) patients in the MIN group and in 4 (36.4%) patients in the SXT group (P = 0.242). Clinical improvement occurred in 11 (13.4%) patients in the MIN group and in 1 (9.1%) patient in the SXT group (P = 1.0). Clinical success occurred in 55 (67.1%) patients in the MIN group and in 6 (54.5%) patients in the SXT group (P = 0.503). Total duration of antimicrobial therapy (P = 0.3198), in-hospital mortality (P = 1.0), hospital length of stay (P = 0.9668), intensive care unit (ICU) length of stay (P = 0.1384), and 30-day readmission (P = 0.686) were similar between groups. Conclusions and Relevance: Rates of clinical failure, clinical improvement, or clinical success were similar between MIN and SXT for nonurinary monomicrobial S. maltophilia infections. [ABSTRACT FROM AUTHOR]

Background: We aim to study the impact of postoperative Stenotrophomonas maltophilia infections among cancer patients undergoing major surgery. Methods: Ambispective, observational study. Study period from 1st November 2019 to 31st March 2024. The study population included patients with a definite diagnosis of cancer who underwent a major surgical procedure in a single, dedicated surgical unit and developed postoperative infection which showed a documented growth of Stenotrophomonas maltophilia. Clinical and laboratory parameters were collected and data represented as median values, percentages and range. Results: Nine patients were identified to have Stenotrophomonas maltophilia infection in the postoperative period among a total of 2506 patients. Co-morbid illnesses were noted in 33.3% patients; all were nosocomial infections. Fever was a manifestation in 77.8% patients, 44.4% had leukocytosis. Of all samples, 33.3% were respiratory ones. Co-infection was noted in 44.4% patients. Sensitivity to trimethoprim-sulphamethoxazole was seen in 44.4% and to levofloxacin in 66.7% isolates. Mortality rate was 11.1%. Conclusion: Stenotrophomonas maltophilia causes uncommon but clinically significant infections among cancer patients in the postoperative period. [ABSTRACT FROM AUTHOR]

Growing interest in probiotics has spurred research into their health benefits for hosts. This study aimed to evaluate the probiotic properties, especially antibacterial activities and the safety of two Weissella confusa strains, W1 and W2, isolated from Khao-Mahk by describing their phenotypes and genotypes through phenotypic assays and whole genome sequencing. In vitro experiments demonstrated that both strains exhibited robust survival under gastric and intestinal conditions, such as in the presence of low pH, bile salt, pepsin, and pancreatin, indicating their favorable gut colonization traits. Additionally, both strains showed auto-aggregation and strong adherence to Caco2 cells, with adhesion rates of 86.86 ± 1.94% for W1 and 94.74 ± 2.29% for W2. These high adherence rates may be attributed to the significant exopolysaccharide (EPS) production observed in both strains. Moreover, they exerted remarkable antimicrobial activities against Stenotrophomonas maltophilia, Salmonella enterica serotype Typhi, Vibrio cholerae, and Acinetobacter baumannii, along with an absence of hemolytic activities and antibiotic resistance, underscoring their safety for probiotic application. Genomic analysis corroborated these findings, revealing genes related to probiotic traits, including EPS clusters, stress responses, adaptive immunity, and antimicrobial activity. Importantly, no transferable antibiotic-resistance genes or virulence genes were detected. This comprehensive characterization supports the candidacy of W1 and W2 as probiotics, offering substantial potential for promoting health and combating bacterial infections. [ABSTRACT FROM AUTHOR]

The aim of this review is to synthesise the key aspects of the epidemiology, current microbiological diagnostic challenges, antibiotic resistance rates, optimal antimicrobial management, and most effective prevention strategies for Stenotrophomonas maltophilia (SM) in the intensive care unit (ICU) population. In recent years, resistance surveillance data indicate that SM accounts for less than 3% of all healthcare-associated infection strains, a percentage that doubles in the case of ventilator-associated pneumonia (VAP). Interestingly, SM ranks as the third most isolated non-glucose fermenter Gram-negative bacilli (NFGNB). Although this NFGNB genus has usually been considered a bystander and colonising strain, recently published data warn about its potential role as a causative pathogen of severe infections, particularly pneumonia and bloodstream infections (BSI), not only for the classical immunocompromised susceptible host patients but also for critically ill ones even without overt immunosuppression. Indeed, it has been associated with crude 28-day mortality as high as 54.8%, despite initial response following targeted therapy. Additionally, alongside its intrinsic resistance to a wide range of common antimicrobials, various worldwide and local surveillance studies raise concerns about an increase in ICU settings regarding resistance to first-line drugs such as cotrimoxazole or tigecycline. This scenario alerts ICU physicians to the need to reconsider the best stewardship approach when SM is isolated in obtained samples from critically ill patients. Despite the coverage of this multidrug-resistant bacterium (MDRB) provided by some traditional and a non-negligible number of current pipeline antimicrobials, an ecological and cost-effective strategy is needed in the present era. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia is a model organism exhibiting intrinsic antibiotic resistance, primarily due to its production of Mβ-lactamase enzymes that inactivate β-lactam antibiotics. This study aims to synthesize an azo derivative containing an oxazepine ring as a potential inhibitor of Mβ-lactamase. The molecular docking results revealed that the binding energies of the Mβ-lactamases ranged from − 5.95 to − 6.09 kcal/mol, indicating favourable interactions with the synthesized compounds. Two compounds were prepared: the first via aldol condensation of (A1) with p-hydroxybenzaldehyde to form (K1) and the second through Azo-Schiff base formation from 3,5-dimethylaniline, resulting in (L2) and (L18). Characterization of these compounds was conducted via FT-IR, CHN, 1H NMR, and 13C NMR spectroscopy. Antimicrobial activity was assessed through minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) tests, which yielded values ranging from 1.19 ± 1 to 0.02 µg/mL and from 1.12 ± 1 to > 0.04 µg/mL, respectively. Notably, the MBC/MIC ratios indicated that L2 and L18 exhibited significant bactericidal activity. In silico analysis via MOE 2015 software allowed us to determine the binding poses and energies of the synthesized inhibitors against Mβ-lactamase (PDB ID: 6UAF). The most stable conformation from the docking results was selected for further evaluation. Compared with standard ceftazidime, the synthesized compounds significantly inhibited Mβ-lactamase activity. Additionally, ADMET analysis indicated favourable pharmacokinetic profiles and low toxicity, suggesting promising oral drug-like properties for the synthesized molecules.

The article in the Journal of Clinical Investigation discusses the effects of Elexacaftor/tezacaftor/ivacaftor (ETI) on cystic fibrosis infections over 3.5 years of treatment. The study found that while ETI maintained reductions in sputum pathogen density, it did not increase the effects of treatment. The research suggests that the durability of ETI-associated infection responses may be influenced by bacterial adaptations and the initial pathogen burden. Additionally, the study highlights the challenges in eradicating infections and the importance of continued research in understanding the long-term effects of ETI treatment on cystic fibrosis infections. [Extracted from the article]

Abstract Background Urinary tract infection is one of the most common infections in humans, affecting women in more proportion. The bladder was considered sterile, but it has a urinary microbiome. Moreover, intracellular bacteria (IB) were observed in uroepithelial cells from children and women with urinary tract infections (UTIs). Here, we evaluated the presence of IB in urine from healthy people and patients with UTI symptoms. Methods Midstream urine was self-collected from 141 donors, 77 females and 64 males; 72 belonged to the asymptomatic group and 69 were symptomatic. IB was characterized by a culture-dependent technique and visualized by confocal microscopy. Urine was also subjected to the classical uroculture and isolated bacteria were identified by MALDI-TOF. Results One-hundred and fifteen uroculture were positive. A significant association was observed between the presence of symptoms and IB (P = 0.007). Moreover, a significant association between the presence of IB, symptoms and being female was observed (P = 0.03). From the cases with IB, Escherichia coli was the most frequent microorganism identified (34.7%), followed by Stenotrophomonas maltophilia (14.2%), Staphylococcus spp (14.2%), and Enterococcus faecalis (10.7%). Intracellular E. coli was associated with the symptomatic group (P = 0.02). Most of the intracellular Staphylococcus spp. were recovered from the asymptomatic group (P = 0.006). Conclusions Intracellular bacteria are present in patients with UTI but also in asymptomatic people. Here, we report for the first time, the presence of S. maltophilia, Staphylococcus spp., and Enterobacter cloacae as intracellular bacteria in uroepithelial cells. These findings open new insights into the comprehension of urinary tract infections, urinary microbiome and future therapies. Uroculture as the gold standard could not be enough for an accurate diagnosis in recurrent or complicated cases.