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PubMed2026

Multiomic insights into fungal polylactic acid degradation: Metabolic adaptation and hydrolytic mechanisms of Sporobolomyces pararoseus.

Polylactic acid (PLA), a biodegradable polyester from renewable resources, is a sustainable alternative to petrochemical plastics. However, its environmental degradation is inefficient naturally, requiring specific microbial activities. While bacterial PLA-degrading mechanisms are well documented, fungal degrading systems-particularly their molecular mechanisms-are underexplored.We isolated Sporobolomyces pararoseus ZRQ01 from the gut microbiota of PLA-fed mealworms. This fungal strain noticeably degraded PLA in PLA-containing medium supplemented with 2% glucose. Biodegradation assays revealed 22.8% loss of the PLA film weight after 35 days of incubation, and scanning electron microscopy confirmed extensive surface erosion and pore formation. Integrated transcriptomic and proteomic analyses, together with the reference genome of S. pararoseus ZRQ01, revealed that S. pararoseus ZRQ01 upregulates hydrolytic enzymes at both transcript and protein levels to cleave PLA into lactic acid. After lactic acid is transferred into S. pararoseus ZRQ01 cells by monocarboxylate transporters with increased abundance, it is assimilated by pathways of pyruvate metabolism and the TCA cycle with increased protein abundance. Intriguingly, upregulation of genes in autophagy-related and MAPK signaling pathways underscores an adaptive stress response potentially supporting cellular homeostasis and degradation-related gene expression. Our results highlight S. pararoseus ZRQ01's metabolic potential for bioremediation and offer insights into fungal bioplastic degradation pathways.

Polyesters↗

PubMed2026

[Complex therapy of chronic bacterial prostatitis using the immunomodulatory drug sodium aminodihydrophthalazinedione].

INTRODUCTION: Chronic bacterial prostatitis (CBP) is characterized by a recurrent course caused by pathogen persistence and impaired local immunity of the prostate. AIM: To assess the effectiveness of the use of sodium aminodihydrophthalazinedione in the complex therapy of chronic bacterial prostatitis. MATERIALS AND METHODS: The prospective comparative study included 60 men aged 21-50 years with CBP (NIH category II). Patients were randomized into two groups of 30: the comparison group received levofloxacin 500 mg/day for 28 days; the main group additionally received rectal sodium aminodihydrophthalazinedione. NIH-CPSI, IPSS, QoL, uroflowmetry, leukocyte and lecithin body counts in prostatic secretion, and bacteriological examination were assessed at baseline and on day 28, and the recurrence rate over 3 months. RESULTS: By day 28, the main group showed a more pronounced decrease in the total NIH-CPSI score (8.1+/-2.1 vs 13.4+/-2.6; p<0.001), restoration of lecithin bodies (+65.1% vs +24.5%; p<0.05), normalization of uroflowmetry, and pathogen eradication in 86.7% vs 66.7% of patients (p<0.05). The 3-month recurrence rate decreased from 26.7 to 10.0% (p<0.05). No adverse events were registered. DISCUSSION: The advantage of combinationtherapy is due to the combination of anti-inflammatory,immunomodulatory,antioxidantandregenerativeeffects of the drug,which is confirmed by the restoration of the secretoryfunction of the prostateepitheliumaccording to the dynamics of lecithingrains. CONCLUSION: The inclusion of sodium aminodihydrophthalazinedione in the combination therapy of CBP increases the clinical and microbiological efficacy of treatment and reduces the recurrence rate.

Humans↗

PubMed2026

Ruling out pediatric bacterial epididymo-orchitis with urinalysis - The case for minimizing unnecessary antibiotic prescription.

INTRODUCTION: Epididymo-orchitis in pediatric patients is predominantly non-bacterial, often stemming from viral or reactive etiologies. Despite guidelines recommending conservative management for non-bacterial cases, antibiotic overtreatment remains prevalent in the outpatient setting. We evaluated the diagnostic accuracy of urinalysis in ruling out bacterial infection to support antibiotic stewardship in this population. METHODS: We conducted a cross-sectional diagnostic accuracy study using electronic health records from a large health maintenance organization in Israel. The cohort included patients younger than 18 years with a diagnosis of epididymo-orchitis or clinically overlapping entities (acute scrotum, appendage torsion) who had paired urinalysis and urine culture results within one week of diagnosis. Logistic regression and ROC curve analysis were performed to assess the ability of urinalysis parameters to predict positive urine cultures. RESULTS: Of 682 eligible cases, confirmed bacterial infection was rare, occurring in only 17 patients (2.5%). Nitrite positivity was the strongest independent predictor of infection (OR 43.98; p < 0.001). A prediction model incorporating all urinalysis parameters yielded an area under the curve (AUC) of 0.825 and achieved a 97.7% classification accuracy for correctly predicting negative cultures. Despite the low prevalence of infection, antibiotics were prescribed in 237 cases (34.7%). Urinary anatomic abnormalities were significantly associated with culture positivity. CONCLUSIONS: Bacterial coinfection in pediatric epididymo-orchitis is uncommon. Urinalysis serves as a highly accurate screening tool to rule out bacterial etiology. A negative urinalysis supports withholding antibiotics in this setting, reserving treatment for children with positive markers or known anatomic abnormalities. This evidence-based approach This evidence-based approach has the potential to reduce unnecessary antibiotic exposure, however prospective studies are needed to validate these findings before broad implementation.

Humans↗

PubMed2026

Molecular Diagnostics for WHO Priority Bacterial Pathogens: A Bibliometric Mapping of Diagnostic Platforms, Resistance Markers, and Antimicrobial Resistance Research Trends.

Antimicrobial resistance (AMR) constrains effective treatment and carries implications for infection control, surveillance, and public health. The World Health Organization (WHO) priority bacterial pathogen framework has intensified the need for diagnostic innovation by redefining research priorities around organisms combining high disease burden with complex resistance profiles. Molecular diagnostics have accordingly moved beyond culture-based workflows, integrating rapid pathogen identification, resistance-marker detection, genomic surveillance, and clinical decision support. The present study conducted a bibliometric mapping of the literature on WHO priority pathogens. Rather than addressing resistance at a general level or a single pathogen or technology, it integrates priority pathogens, molecular platforms, and resistance markers within a single framework, tracing their joint thematic and temporal evolution along an explicit pathogen-platform-marker axis. Scopus-indexed articles and reviews (2000-2025) were retrieved, yielding 1746 publications after screening adapted from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Analyses used Bibliometrix/Biblioshiny, R, and VOSviewer. The literature expanded markedly after 2018, led by China and the United States. Methicillin-resistant Staphylococcus aureus (MRSA), Mycobacterium tuberculosis, Enterococcus faecium, and the Enterobacterales-carbapenemase axis constituted the principal thematic cores, whereas conventional polymerase chain reaction (PCR)/nucleic acid amplification testing (NAAT) and whole-genome sequencing were the dominant platforms. Overall, the field has evolved from pathogen detection into an AMR-centered translational domain encompassing resistance prediction, genomic epidemiology, surveillance, and clinical decision support. Diagnostic development, stewardship, and surveillance depend on hybrid workflows coupling rapid marker-targeted assays with genome-based characterization, delivering actionable resistance within clinically meaningful timeframes, and extending coverage to underrepresented pathogens and platforms.

Humans↗

PubMed2026

[Comparative analysis of comprehensive treatment outcomes in patients with chronic bacterial prostatitis with the addition of the multicomponent complex AndrOPREN].

INTRODUCTION: Type II chronic bacterial prostatitis is characterized by persistent infection, insufficient efficacy of standard therapy, and a high recurrence rate, which necessitates the search for additional treatment options. AIM: To evaluate the efficacy and safety of adding the multicomponent complex AndrOPREN to comprehensive therapy for type II chronic bacterial prostatitis. MATERIALS AND METHODS: This prospective, comparative, randomized study included 233 patients allocated to the main group (n=126) and the control group (n=107). In both groups, patients received standard therapy; men in the main group additionally received the multi-ingredient complex AndrOPREN at a dose of two capsules of No. 1 and two capsules of No. 2 daily for 1-2 months. The follow-up period was 60 days. Changes in symptoms according to the IPSS and QoL scores, urinalysis parameters, microscopy findings of expressed prostatic secretions, pathogen eradication, and biochemical safety parameters were assessed. RESULTS: Improvement was observed in both groups and was more pronounced in the main group. By day 14, the median IPSS score was 14.0 [12.0; 16.0] vs. 18.0 [15.0; 20.0] in the control group (p<0.001); by day 60, the corresponding values were 7.0 [5.0; 9.0] and 11.0 [9.0; 13.0] (p<0.001). At the end of follow-up, the QoL score was 2.0 [1.0; 2.0] and 3.0 [2.0; 3.0], respectively. No microbial growth was detected in 91.2% and 80.4% of patients, respectively (p=0.026); Escherichia coli eradication was achieved in 91.7% and 76.9%, respectively. No biochemical changes indicative of nephrotoxicity or hepatotoxicity were detected. DISCUSSION: The addition of the multicomponent complex AndrOPREN was associated with more rapid symptom resolution, a reduction in inflammatory changes, restoration of the secretory function of the prostate, and greater microbiological efficacy. CONCLUSION: The addition of the multicomponent complex AndrOPREN to comprehensive therapy for type II chronic bacterial prostatitis improves treatment efficacy while maintaining a favorable safety profile.

Humans↗

PubMed2026

Cefoxitin versus cefotaxime as empirical treatment of spontaneous bacterial peritonitis in liver cirrhotic patients: randomized controlled clinical trial.

BACKGROUND: Spontaneous bacterial peritonitis (SBP) is a severe complication of cirrhosis requiring immediate empirical antibiotic therapy. Third-generation cephalosporins are the traditional agents of choice; however, increasing clinical failure rates necessitate the evaluation of alternative antibiotics to ensure optimal therapeutic outcomes. The aim was to investigate the efficacy of cefoxitin versus cefotaxime for SBP treatment. METHODS: A randomized clinical trial was conducted on 140 cirrhotic patients with community-acquired SBP at Al-Rajhy Liver University Hospital, Assiut, Egypt. Patients were randomized to receive either cefotaxime (n = 70) or cefoxitin (n = 70), 2 g every 8 h for 5 days. Polymorphonuclear neutrophil (PMN) counts were measured upon admission, on Day 2 and on Day 5. Clinical response rates at Days 2 and 5, development of hepatorenal syndrome, length of stay and mortality were assessed. RESULTS: According to intention-to-treat analysis, clinical response rates at Day 2 were 74.2% in the cefotaxime group and 80% in the cefoxitin group, while at Day 5, they were 71.4% and 74.3%, respectively (P = 0.704). The PMN counts at Days 0, 2 and 5 showed no significant differences between the cefotaxime and cefoxitin groups (P = 0.889, 0.909 and 0.360, respectively). The incidence of hepatorenal syndrome was 7.1% in the cefotaxime group compared with 8.6% in the cefoxitin group (P = 0.753), and mortality was 15.7% and 12.9%, respectively (P = 0.629). CONCLUSIONS: Cefoxitin showed comparable effectiveness to cefotaxime but may be utilized in selected clinically stable SBP patients.

Humans↗

PubMed2026

Metal-organic frameworks nanozyme-integrated portable microneedle patch for visual bacterial monitoring in meat.

Foodborne microbial contamination is a major global health concern, with conventional methods often being time-consuming and complex. Herein, we developed a novel portable biosensor by integrating microneedle patch technology and a metal-organic framework (Fe/Cu-NBDC MOF) nanozyme, enabling rapid, on-site, visual detection of bacteria in meat. The sensing system works by encapsulating aptamer-functionalized MOF nanozymes within a hydrogel patch, where their catalytic sites are initially blocked by the aptamer. In the presence of Staphylococcus aureus (S. aureus) as the target, the specific aptamer's binding to bacteria exposes numerous catalytic sites, further activating the chromogenic reaction of the tetramethylbenzidine‑hydrogen peroxide (TMB-H₂O₂) system, enabling visual detection of S. aureus. The biosensor demonstrates a detection limit of 82 CFU/mL with excellent specificity to successfully apply to commercial mutton. By integrating sampling, enrichment, and visual detection into a single compact device, this platform offers a practical, efficient solution for rapid on-site screening of foodborne pathogens.

Biosensing Techniques↗

PubMed2026

Genomic epidemiology of clinically critical antibiotic resistance in Salmonella enterica causing bloodstream infections across six Chinese provinces, 1994-2023.

Clinically critical antibiotic-resistant Salmonella enterica (S. enterica) causing bloodstream infections remains a public health challenge. Here, we aim to reveal the emergence and trends of clinically important antibiotic resistance in S. enterica causing bloodstream infections using 833 isolates from six Chinese provincial-level administrative areas during 1994-2023. We identified 48 serovars and 64 sequence types (STs). Overall, 8.52% of 833 isolates were resistant or had decreased susceptibility to ciprofloxacin, 4.32% and 6.84% reported resistance or decreased susceptibility to third- and fourth-generation cephalosporins (3GCs and 4GCs), 1.80% reported resistance to fosfomycin, and 2.16% reported resistance to azithromycin. Across these six regions, azithromycin and fosfomycin resistance is increasing, as is decreased susceptibility or resistance to ciprofloxacin, 3GCs, and 4GCs, especially among younger children and elderly people. Clinically prioritized antibiotic resistance also varies by region, serovar, and age group. S. Paratyphi A genotype 2.3.3 strains are mainly divided into 2 lineages distributed in Guangxi and Shanghai. Within the scope of this passive surveillance dataset, S. Typhi genotype 4.3.1.2.1 was identified as the earliest documented case among the collected isolates. Our retrospective and longitudinal genomic epidemiology study provides critical data for the formulation of treatment guidelines and policies for bloodstream infections and for the monitoring and control of antimicrobial resistance.

Humans↗

PubMed2026

Bacterial Lysates Add-On Therapy to Reduce Postoperative Recurrence in Nasal Polyps.

OBJECTIVE: This study aimed to investigate the potential role of OM-85 in reducing polyp recurrence (PR). METHODS: A single-center randomized, prospective study was performed to compare the inter-group PR rate, patient-reported outcome measures (PROMs), CT and endoscopic scores. Hundred patients were randomized to receive either add-on OM-85 (34/50) or control group (43/50); 77 participants completed the 12-month follow-up. The OM-85 group received oral treatment for 10 days, followed by a 20-day washout (Months 1-3 and 7-9). Primary outcome was the PR rate. Secondary outcomes included PROMs, Lund-Kennedy (L-K) scores, Lund-Mackay (L-M) scores, and complete blood count (CBC) parameters. RESULTS: The PR rate was significantly lower in the OM-85 group (8.82%) than in the control group (27.91%, χ 2 = 4.408, p = 0.036). Univariable analysis identified pre-operative Lund-Mackay (L-M) score (p = 0.008) and hyposmia VAS score (p = 0.031) as significant predictors of PR. In multivariable analysis, the L-M score remained an independent predictor (OR = 1.15, p = 0.012), with an optimal cutoff of 10. The OM-85 group showed significant improvements in nasal obstruction, olfactory dysfunction, and mucopurulent discharge at 6 and 12 months (p < 0.05). Lund-Kennedy (L-K) score and 22-item Sinonasal Outcome Test (SNOT-22) score were also significantly improved (p < 0.05). Furthermore, the OM-85 group exhibited elevated white blood cell counts and lymphocyte percentages from 6 months onward (p < 0.05). CONCLUSION: Adjuvant OM-85 may reduce postoperative PR, with improved endoscopic and symptom scores, potentially mediated by enhanced systemic immune function.

Humans↗

PubMed2026

Comparative genomic epidemiology of food- and patient-derived diarrheagenic Escherichia coli from sentinel surveillance in Southeast China.

Diarrheagenic Escherichia coli (DEC) remains an important foodborne pathogen, yet long-term comparative genomic surveillance data jointly characterizing food-derived and patient-derived isolates remain limited. This surveillance-based comparative study integrated antimicrobial susceptibility testing and whole-genome sequencing to characterize diarrheagenic Escherichia coli isolates recovered from food and patient sources in Lishui, Southeast China, during 2018-2025, with emphasis on occurrence, resistance profiles, genomic backgrounds, and plasmid replicon-associated features. Antimicrobial susceptibility testing was performed for 258 selected isolates, and whole-genome sequencing was conducted for a curated analytical subset of 204 isolates. The sequenced subset was used for diversity-oriented comparative genomic analysis rather than for unbiased prevalence estimation of the entire DEC collection. EAEC predominated in both sources, although food-associated occurrence was heterogeneous across categories, with the highest recovery rate observed in raw meat. Patient-derived isolates showed a broader overall resistance burden, whereas food-derived isolates retained substantial resistance to tetracycline, chloramphenicol, and florfenicol. Phylogenetic analysis showed partial overlap in genomic backgrounds between food-derived and patient-derived isolates, while representative resistance determinants displayed both broadly distributed and lineage-enriched patterns. Replicon-based plasmid profiling identified 42 plasmid types, including 12 detected in both sources, with IncF-related replicons predominating among these shared profiles. Several food-derived isolates carried multiple plasmid replicon types that were also observed in patient-derived isolates. Overall, food-derived and patient-derived DEC showed partial overlap in genomic backgrounds, resistance determinants, and replicon-defined plasmid profiles within this surveillance setting, while retaining source-associated heterogeneity. These findings should be interpreted as surveillance-based comparative evidence rather than as evidence of direct source attribution or transmission.

Humans↗

PubMed2026

A black soybean yoghurt fermented with a reusable probiotic cellulose gel: beneficial effects and metabolic characteristics.

The demand for plant-based yoghurts is continuously increasing. However, achieving stable physicochemical properties and acceptable flavor of the plant-based yoghurts remains challenging. In our previous work, we encapsulated Lactiplantibacillus plantarum (L. plantarum) LCC-605 biofilm into bacterial cellulose (BC), obtaining a LP605@BC gel. LP605@BC gel exhibited excellent harsh-environment resistance abilities and storage stability, and is very suitable as a starter culture. In this work, we used LP605@BC as a starter culture to prepare the fermented plant-based yoghurt (e.g., black soybean yoghurt, BSY-LP605@BC). After fermentation, the inverted nonflowing yoghurt was formed due to the strong interaction between protein and exopolysaccharide (EPS) produced by LCC-605 during fermentation. In addition, the water holding capacity (67.2%) of BSY-LP605@BC was also greatly improved. The viable bacterial counts in BSY-LP605@BC reached 11.2 log CFU/mL after 21 days of storage. BSY-LP605@BC showed increased antioxidant, cholesterol-lowering abilities, and hypoglycemic potential compared with the unfermented black soybean milk. Interestingly, LP605@BC could be reused at least 5 times, demonstrating excellent sustainability. Significant metabolomic differences between BSY-LP605@BC and the black soybean milk were observed via untargeted metabolomic analysis, further proving the beneficial effects of BSY-LP605@BC. Overall, our work developed an effective reusable starter culture for preparing the plant-based yoghurt in a sustainable manner, providing a new design direction and form of starter culture.

Yogurt↗

PubMed2026

Clinical Outcomes and Genomic Epidemiology of Multidrug-Resistant Methicillin-Resistant Staphylococcus aureus Keratitis.

PURPOSE: To characterize the clinical features, management, antimicrobial resistance patterns, and genomic epidemiology of methicillin-resistant Staphylococcus aureus (MRSA) keratitis at two North American centers. DESIGN: Retrospective interventional case series combined with laboratory investigation PARTICIPANTS: Seventy eyes of 67 patients presenting laboratory-confirmed MRSA keratitis were included METHODS: We performed a multicenter retrospective case series of patients with culture-proven MRSA keratitis treated between 2005 and 2022. Demographic and clinical data were collected. Antimicrobial susceptibility testing was conducted, and multidrug resistance (MDR) was defined as resistance to ≥3 antibiotic classes. A subset of isolates underwent whole-genome sequencing with core genome multilocus sequence typing. Vancomycin susceptibility, heteroresistance screening, and tolerance testing were performed on available isolates. MAIN OUTCOME MEASURES: Antimicrobial susceptibility and multidrug resistance rates, vancomycin phenotypic profiles, MRSA genotypic distribution, and final best-corrected visual acuity RESULTS: Median age was 63.5 years, and 61.4% were female. Ocular surface disease (67.7%) and prior ocular surgery (65.2%) were common. Only 25.4% had significant healthcare exposure in the preceding year. Most isolates (85.7%) were MDR. Fluoroquinolone susceptibility was low (moxifloxacin 19.7%). All isolates were susceptible to vancomycin (MIC₉₀ 2 µg/mL), and no vancomycin-intermediate, heteroresistant, or tolerant phenotypes were identified. Whole genome sequencing (n = 41) demonstrated predominance of clonal complexes 5 (68.3%) and 8 (29.2%). Visual outcomes were poor, with most patients (85.2%) having a final visual acuity worse than 20/60 among those with follow-up. CONCLUSIONS: MRSA keratitis is associated with high rates of multidrug resistance and poor visual outcomes despite guideline-based therapy. Infections were predominantly caused by CC5 MDR strains despite limited recent healthcare exposure. These findings highlight the persistence of highly resistant MRSA lineages in community-associated corneal infection and underscore the need for ongoing antimicrobial surveillance and optimized treatment strategies.

Humans↗

PubMed2026

Illicium verum polysaccharide targets fimbriae and flagella to disrupt biofilm and inhibit multidrug-resistant Escherichia coli proliferation.

The widespread dissemination of multidrug-resistant (MDR) E. coli has led to a decrease in the efficacy of antibiotics, posing severe challenges to clinical anti-infective therapy. Owing to their safety, multitarget activities, and low risk of inducing drug resistance, plant polysaccharides represent a promising alternative strategy. In this study, an acidic polysaccharide (IVP-3) was isolated and purified from the medicinal and edible plant Illicium verum, and it was found to inhibit MDR E. coli colonization by disrupting its biofilm. The Mw of IVP-3 was determined to be 35.566 kDa. Its backbone consists of →4)-α-D-GalpA-6-OMe-(1→, →4)-α-D-GalpA-(1→, →4)-β-D-Galp-(1→, and →3,4)-α-D-GalpA-(1 → residues, whereas the branched chain is composed of α-L-Araf-(1 → 5)-α-L-Araf-(1 → attached to the O-5 position of →2,5)-α-L-Araf-(1→, which is further linked to the O-3 position of the backbone. Mechanistically, IVP-3 disrupts the structure of fimbriae and flagella, inhibits bacterial motility, effectively prevents initial biofilm adhesion, and eradicates preformed mature biofilms. Additionally, IVP-3 damages cell membrane integrity, disrupts the proton motive force, and induces energy metabolism disorder, efflux pump inhibition, and oxidative stress, ultimately leading to bacterial lysis. This study provides a theoretical basis for the development of natural antibacterial agents targeting MDR E. coli biofilms and for the high-value utilization of Illicium verum.

Biofilms↗

PubMed2026

Tigecycline-resistant Staphylococcus in waiting pens of a pig slaughterhouse: genomic insights into a food safety alert.

BACKGROUND: The waiting pens of slaughterhouses represent a critical control point in the 'farm-to-fork' continuum, yet their role in the emergence and dissemination of antimicrobial resistance remains understudied. This study investigated tigecycline-resistant Staphylococcus (TRS) in these high-risk zones to assess their prevalence, resistance mechanisms, and transmission dynamics. METHODS: 400 samples were collected from the waiting pens of a pig slaughterhouse in Guangzhou, China. Antimicrobial susceptibility testing, whole-genome sequencing, phylogenetic analysis, and molecular cloning were employed to characterize resistance mechanisms and transmission patterns. RESULTS: 78 TRS strains were isolated and classified into three species, including S. borealis, S. ureilyticus, and S. pasteuri. These isolates exhibited multidrug-resistant phenotypes and carried new mutations in rpsJ and tet(M), which were functionally confirmed to reduce tigecycline susceptibility. Phylogenetic evidence demonstrated clonal transmission between pig farms and the slaughterhouse. The tet(M) gene was located within Staphylococcal cassette chromosome mec elements mediated by IS257, while tet(L) was carried by plasmids formed through IS256/IS257-mediated recombination. CONCLUSIONS: Waiting pens serve as crucial reservoirs for the amplification and dissemination of antimicrobial resistance. Our findings underscore the urgent need for enhanced biosecurity measures, improved waste management, and routine molecular surveillance in these high-risk zones to mitigate the spread of resistance along the food production chain.

Animals↗

PubMed2026

Routine methods misidentify Serratia spp.: Limitations of MALDI-TOF MS revealed by whole-genome sequencing.

Accurate species-level identification within the genus Serratia remains challenging due to extensive phenotypic overlap and high genomic relatedness among closely related and recently described taxa. This study presents an evaluation of routine and genome-based identification approaches applied to clinical Serratia isolates, integrating phenotypic assays, MALDI-TOF MS (Bruker Daltonics), 16S rRNA gene sequencing, and Whole-Genome Sequencing (WGS). A total of 103 isolates collected from a teaching hospital were analyzed. WGS was performed on a subset of isolates. Conventional biochemical methods classified all isolates as Serratia marcescens, whereas MALDI-TOF MS identified 60.1% as S. marcescens, 11.6% as S. ureilytica, and 28.1% just at the genus level. Peak analysis from MALDI-TOF MS revealed specific peaks associated with S. marcescens and S. ureilytica, but limited discriminatory power. WGS of six isolates initially identified as S. ureilytica by MALDI-TOF MS revealed reclassification as Serratia sarumanii (n = 5) and Serratia montpellierensis (n = 1), supported by Average Nucleotide Identity (ANI), Average Amino Acid Identity (AAI), and Digital DNA-DNA Hybridization (dDDH) thresholds. In contrast, 16S rRNA analysis showed limited species-level resolution. Phylogenomic and SNP-based analyses confirmed these classifications with strong support. Overall, this study underscores the critical role of high-resolution genomic approaches for precise species identification and highlights the need for continuous expansion and curation of MALDI-TOF MS reference databases to support reliable clinical diagnostics and epidemiological surveillance of emerging Serratia species.

Spectrometry, Mass, Matrix-Assisted Laser Desorpti↗

PubMed2026

Insights into the fate and dynamics of antibiotic resistance in multidrug-resistant Bacillus cereus during in vitro simulated gastrointestinal digestion.

Bacillus cereus, an important pathogen responsible for causing foodborne diseases worldwide, releases pore-forming enterotoxins, which target host epithelial cells, leading to osmotic lysis and ultimately manifesting as diarrheal syndrome. Moreover, some B. cereus strains carry antimicrobial resistance genes that confer multidrug resistance against a spectrum of antibiotics. Characterizing the survival traits of multidrug-resistant (MDR) B. cereus strains in the intestinal microenvironment is essential for developing targeted strategies to effectively manage diarrheal foodborne diseases caused by this pathogen. This study used whole-genome sequencing (WGS) to evaluate the pre- and post-digestion toxigenic potential, antimicrobial resistance profiles, and genetic diversity of MDR B. cereus strains isolated from food samples in Guangdong Province, China. The four B. cereus isolates investigated in this study exhibited a genetic diversity, as determined by multilocus sequence typing analysis of WGS data. All four isolates produced the diarrheal toxins Hbl, Nhe, and CytK to varying levels, indicative of their potential to cause outbreaks of foodborne diseases. Each of the four isolates exhibited resistance to more than three classes of antibiotics, fulfilling the criterion for multidrug resistance. At an initial concentration of 9 log colony-forming units (CFU)/mL, the intestinal concentration of these four isolates crossed the threshold required to induce widespread diarrhea in the general population. Under rice slurry protection, all tested isolates maintained intestinal concentration beyond the threshold when the initial concentration was increased to ≥8 log CFU/mL. Moreover, the upregulations of genes associated with acid tolerance, bile tolerance and stress response were observed in the surviving MDR B. cereus isolates. Digestion markedly altered the antibiotic resistance profiles of the MDR B. cereus isolates. In the absence of a food matrix, the MDR isolates lost their resistance to imipenem, meropenem, amoxicillin-clavulanic acid, and trimethoprim-sulfamethoxazole post-digestion and was influenced by the initial concentration of the strains. In the presence of food matrix rice slurry, the effects of digestion on the antibiotic resistance of MDR B. cereus isolates can be mitigated, enabling them to maintain their antibiotic resistance to the greatest extent. Most remarkably, after digestion, the isolates Bce055 and Bce166 exhibited newly emergent resistance to cefotetan and trimethoprim-sulfamethoxazole, respectively. Our findings clarify the fate of MDR B. cereus isolates in the gastrointestinal tract and inform the development of prevention and control strategies for foodborne diseases caused by this pathogen.

Drug Resistance, Multiple, Bacterial↗

PubMed2026

Herd-level heterogeneity of antimicrobial resistance in commensal Escherichia coli: A nationwide high-throughput survey of Australian pig herds.

Antimicrobial resistance in commensal Escherichia coli provides a useful indicator for overall antimicrobial resistance burden. We applied this approach to assess antimicrobial resistance within and between commercial pig herds across Australia. A high-throughput robotic workflow was used to isolate 2730 E. coli colonies from rectal contents collected in 2022 from healthy slaughter pigs (n = 300) representing 30 herds (∼70% of national production). Up to 94 isolates per herd underwent antimicrobial susceptibility testing using the Robotic Antimicrobial Susceptibility Platform. Isolate- and herd-level antimicrobial resistance indices were calculated, weighting antimicrobials by their human health importance. Resistance to first-line agents was widespread: ampicillin 77% and tetracycline 79%. By contrast, resistance to critically important antimicrobials was rare (ciprofloxacin 0.11%; extended-spectrum cephalosporins 0.04%), and no clinical resistance to carbapenems or colistin was detected. Overall, 56.9% of isolates were multi-class resistant. Herd-level antimicrobial resistance within indices ranged from 1.51 to 5.76, revealing substantial between-herd heterogeneity. Three herds carried critically important antimicrobials-resistant isolates that would likely have been missed using conventional, lower-density sampling approaches. Whole-genome sequencing identified fluoroquinolone-resistant isolates belonging to ST10 and ST69 (both qnrS1), and ST744 (Quinolone Resistance Determining Region mutations plus blaCTX-M-27). By testing approximately tenfold more isolates than conventional surveys, we uncovered considerable antimicrobial resistance with heterogeneity within and between animals and herds, including farm-specific variability. This expanded sampling also enabled detection of critically important antimicrobial resistance at very low prevalence. In conclusion, high-throughput, high-density testing offers a practical early-warning system and herd-level benchmark to inform surveillance and targeted interventions.

Animals↗

PubMed2026

Genomic and One Health insights into Vibrio parahaemolyticus from environmental, seafood and clinical sources.

Vibrio parahaemolyticus is a leading cause of seafood-borne gastroenteritis worldwide, with climate warming facilitating its spread to high-latitude areas. In this study, we analyzed 212 genomes of environmental and seafood-associated isolates collected from seven cities in Zhejiang Province, China (2019-2024), alongside 228 clinical genomes from public databases. The 212 isolates were assigned to 172 sequence types (STs), with ST490 being the most frequent (5/212, 2.36%). Forty-four serotypes were identified, dominated by OL3:KUT (12.68%). High ST and serotype diversity were observed across different sample types and sources, with median pairwise single nucleotide polymorphisms (SNPs) ranging from 57,431 to 58,378, indicating comparable genetic diversity across groups. All isolates carried tlh and T3SS1 but lacked tdh and T3SS2. Resistance rates against ampicillin and cefazolin were 54.72% (116/212) and 44.34% (94/212), respectively, with multidrug resistance (MDR) detected in nine isolates, predominantly from seafood (7/9). A total of 63 distinct antimicrobial resistance genes (ARGs) spanning seven classes were identified. Isolates from aquaculture farms and wet markets exhibited greater resistance category diversity and higher ARG carriage than those from coastal or riverine sites. In contrast, the 228 clinical isolates harbored only 25 ARGs across two classes, with a significantly lower proportion of isolates carrying multiple ARG classes (0.44% vs. 6.13%, P < 0.001). Human isolates formed tighter phylogenetic clusters, although a minority were closely related to environmental/foodborne strains. Overall, our findings demonstrate the genetic diversity and resistance potential of V. parahaemolyticus across environmental, seafood, and clinical sources, highlighting the importance of the One Health approach to comprehensive public health risk assessment.

Vibrio parahaemolyticus↗