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Lactococcus garvieae is a facultatively anaerobic Gram-positive coccus which causes lactococcosis, a septicaemic illness in fish of major aquacultural significance. This pathogen has emerged in recent years as a cause of zoonotic infections including infective endocarditis, primary bacteraemia, peritonitis and orthopaedic infections, with putative risk factors such as raw seafood ingestion and underlying gastrointestinal disease. We report a case of L. garvieae bioprosthetic aortic and mitral valve endocarditis in a 75-year-old man, complicated by multiple cerebral septic emboli, lumbar discitis/osteomyelitis and bilateral pulmonary nodules. Despite initial stabilization with antibiotic therapy and medical heart failure management, the patient deteriorated approximately a year after his index admission with worsening valvulopathy and ultimately died of complications of his infection. This case highlights the emergence of L. garvieae as an opportunistic pathogen in humans, with increasing cases identified due to improved recognition and enhanced diagnostics.

Background. World Health Organization (WHO) priority bacterial pathogens and ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.) organisms in household wastewater pose critical community transmission risks, yet surveillance data from Sub-Saharan Africa remain limited. This study provides the first comprehensive priority pathogen detection and antimicrobial resistance assessment in household wastewater from Gombe State, Nigeria, focusing on organisms of highest clinical concern. Methods. We conducted targeted surveillance for WHO priority pathogens in 320 household wastewater samples across seven districts in Gombe using multi-stage sampling. Some priority Gram-negative pathogens (Escherichia coli, K. pneumoniae, P. aeruginosa and Enterobacter spp.) were specifically isolated and characterized. Antimicrobial susceptibility testing followed Clinical and Laboratory Standards Institute (CLSI) 2024 guidelines across 12 antibiotics targeting critical resistance patterns. Extended-spectrum beta-lactamase (ESBL) and carbapenemase detection focused on priority pathogen isolates, with PCR confirmation of key resistance genes. Results. Priority pathogen detection revealed E. coli (131 isolates, 32.6%) as the dominant WHO priority pathogen, followed by K. pneumoniae (77 isolates, 19.2%) and P. aeruginosa (45 isolates, 11.2%). The ESKAPE pathogen P. aeruginosa showed 73.3% multidrug resistance (MDR), with carbapenemase gene detection [Verona integron-encoded metallo-beta-lactamase gene (blaVIM), 60%; K. pneumoniae carbapenemase gene (blaKPC), 20%]. The critical priority pathogen K. pneumoniae demonstrated a 79.2% MDR prevalence, with universal beta-lactamase CTX-M gene (blaCTX-M) gene presence (100%) among ESBL producers. Priority pathogen E. coli exhibited an alarming 84.7% MDR rate, with widespread ESBL production (51.5%). Carbapenem resistance among priority pathogens reached 41.3%, indicating last-resort antibiotic failure in critical organisms. Conclusions. Household wastewater in Gombe harbours WHO priority pathogens and ESKAPE organisms with high antimicrobial resistance prevalence. These preliminary findings suggest substantial environmental circulation of resistant bacteria and highlight the need for enhanced surveillance, further investigation of community transmission risks and strengthened antimicrobial stewardship programmes.

The environmental spread of antibiotic-resistant bacteria is a growing global health concern, particularly in low- and middle-income countries where limited wastewater treatment infrastructure may facilitate the dissemination of multidrug-resistant (MDR) organisms. Escherichia coli and Klebsiella spp. are clinically significant MDR pathogens commonly associated with healthcare-associated infections and known to carry diverse antimicrobial resistance genes (ARGs). In this study, we conducted genomic and phenotypic analyses of E. coli and Klebsiella spp. isolated from hospital wastewater and paediatric patient samples at a tertiary hospital in Lima, Peru, between 2017 and 2019. A total of 157 isolates were collected (E. coli, n=113; Klebsiella spp., n=44). Whole-genome sequencing was performed to identify ARGs and assess sequence types (STs). MDR phenotypes were more prevalent among wastewater isolates (73.5%) compared to clinical isolates (56.8%, P=0.014), while extended-spectrum β-lactamase production was more frequent in clinical isolates (52.9 % vs. 13.9 %, P<0.001). Carbapenemase-producing isolates were found only in wastewater, whereas colistin resistance was restricted to a subset of clinical E. coli isolates from urine. Genomic analysis revealed greater sequence type diversity among wastewater isolates, including high-risk STs such as ST10, ST131 and ST405. The Shannon diversity index was higher for wastewater-derived isolates (H=3.45) compared to clinical isolates (H=2.95), indicating a more heterogeneous resistance reservoir. In total, 1,302 resistance gene hits were identified, with clinical isolates carrying significantly more ARGs per genome than wastewater isolates. A small number of shared STs were detected in both sources, suggesting possible overlap in bacterial populations. Our findings highlight the potential role of hospital wastewater as a reservoir of antimicrobial resistance and support the value of integrating environmental and clinical genomic surveillance. Wastewater-based monitoring may inform infection control efforts and guide interventions to curb the spread of AMR within healthcare settings and their surrounding environments.

The extent to which individuals interact online has expanded in recent years, with online networking playing a major aspect of most people's lives. With employers relying on online searches when evaluating job candidates, the development of a positive professional online presence has become an important aspect in most sectors and potentially a challenge for students preparing to enter the workplace. LinkedIn is a globally recognized networking site, enabling individuals to interact within a professional environment. However, it remains uncertain whether students are aware of its benefits and are confident in using it. Alongside other Life Science degree programmes at the University of Glasgow, staff within the Microbiology and Immunology programmes initiated closed LinkedIn groups, which were limited to staff and current or former students of the relevant degree. The aim of these groups was to promote student awareness of the diversity of career roles available post-university and enable students to network in their chosen field, as levels of student engagement with this platform and how it can be utilized by students for professional networking remained unclear. As part of our 'Linked to Get In' workshop, students connected and conducted an interview with an alumnus of their degree, allowing them to develop their networking skills with professionals in their field and enabling exploration of career prospects, prior to presenting their findings to their peers. Confidence in using LinkedIn for networking increased following this session, with all students agreeing that the inclusion of such a workshop in the curriculum is useful for exploring employability options. Moreover, students had increased awareness of the wider benefits the platform had to offer, and it was not only useful for job searching. Our findings show that LinkedIn has the potential for being an effective platform to enable undergraduate students to engage with professionals in their discipline, with the closed format providing a trusted space for students to enhance their networking and communication skills, whilst exploring the career diversity open to them.

Optimization of petroleum hydrocarbon degradation process in contaminated environments could be feasible using biosurfactant-producing bacteria. The aim of this study was to investigate crude oil degradation potential of biosurfactant-producing bacteria isolated from a marine ecosystem in Nigeria. Sediment and water samples were collected from ten marine locations in Nigeria, and physicochemical analyses were carried out on them. Isolates were identified and screened for biosurfactant production and crude oil degradation after 7 days of incubation. The screened isolates were assayed for biosurfactant production and crude oil degradation for 35 days and analysed every 7 days for changes in pH, OD and total petroleum hydrocarbon content. The strains with the highest yields were identified using PCR-based molecular method. Twenty bacterial species were isolated from the marine locations, and 15 of these isolates showed good potential for biosurfactant production and crude oil degradation. The isolates with the highest biosurfactant production using oil spread and emulsification index tests are Pseudomonas aeruginosa Sihong_820_11, P. aeruginosa Strain P73 and Atlantibacter hermannii Strain K167. In addition, these bacterial isolates have the highest crude oil degradation efficiencies of 87%, 68% and 68%, respectively. The findings revealed that biosurfactant-producing bacteria isolated from marine ecosystems within Nigeria could effectively degrade crude oil in contaminated sites. In addition, bacteria with higher potential for biosurfactant production are more efficient in crude oil degradation.

Bioluminescent bioreporters are widely used across various scientific disciplines due to the well-characterized bacterial bioluminescence mechanism. However, solvent-induced membrane perturbations may confound the use of bioreporters in assessing cellular toxicity from environmental contaminants. This study investigated the solvent effect, wherein membrane damage increases intracellular availability of bioluminescent reaction precursors, increasing the light produced. A new online in situ monitoring system was also tested with multiple bioluminescent reporters, including a newly constructed Pseudomonas fluorescens M3A strain, exposed to toluene, trichloroethylene, acetone, phenol and creosote derived from beechwood tar. Additional tests included the introduction of carbon nanotubes, fullerene and fullerenol. A solvent effect was confirmed by the detection of increased bioluminescent signal and the occurrence of fatty acid release (P<0.05). Phenol (25 p.p.m.), a benchmark for bactericidal activity, demonstrated luminescence enhancement via the solvent effect. Membrane toxicity assays showed that P. fluorescens M3A responded sensitively to sublethal and lethal membrane disruptions, whereas Vibrio fischeri MJ1 did not exhibit a solvent effect, and its luminescence changes were not correlated with viability (P>0.05). These results indicate that P. fluorescens M3A is a sensitive biosensor for detecting environmental contaminants and identifying both lethal and sublethal membrane perturbations. The findings underscore essential considerations when utilizing bacterial bioluminescence as a proxy for gene expression or cellular physiology.

Bacterial resistance to antibiotics continues to be a major threat to human health. Agencies, such as the World Health Organization, have called for a multistep response, including increased educational training, both for professionals and the public at large, on this complex problem. Toward that end, we created a laboratory experience, ideally suited for undergraduates, where students observe the development of bacterial resistance over the course of a week. The procedure is conducted in a single container for simplicity and reliably generates resistant strains. Eightfold increases in resistance levels were commonly observed. Multiple variations to the standard method are included and explore the effects of antibiotic concentration and additivity. In performing the activity, students learn basic microbiology techniques, including growing bacterial cultures and determining MICs. Students are able to witness the relative ease with which bacteria can become resistant and then connect this concept to natural selection. The activity itself was created in partnership with undergraduate student researchers, a practice that is becoming more prevalent. Overall, the activity promotes understanding and awareness of antibiotic resistance, which is critically needed to combat this global threat.

Duplication and segregation of genetic material are vital for cell proliferation. Deletion of DNA replication regulators, such as YabA and ParA, leads to over-initiation of DNA replication. However, the viability of the ΔyabA ΔparA double mutant suggests additional regulatory mechanisms. Using a transposon mutagenesis library, yybE was identified as a potential candidate. Bioinformatic analysis of yybE suggests that it encodes a putative LysR-type transcriptional regulator (LTTR). LTTRs are established regulators of metabolic processes, leading to the hypothesis that YybE might link metabolic processes to DNA replication. However, under the tested conditions, deletion of yybE did not result in detectable changes to DNA replication frequency, origin segregation or chromosome morphology.

The Ralstonia solanacearum species complex (RSSC) is a globally distributed group of Gram-negative, soil-borne bacteria that cause wilt diseases on a broad range of hosts. Due to these pathogens' impact on economically important plant species, there is a need for consolidated and visualized information on RSSC pathogen isolation data. We developed an interactive dashboard designed to allow users to explore the diversity and biogeography of the RSSC. The dashboard visualizes data in the form of maps, charts and tables, with a variety of user-interactive filters for taxonomic, geographic and host of isolation specifications. This Ralstonia Wilt Dashboard will aid in communicating knowledge to researchers, regulatory scientists and other stakeholders to improve disease control and regulation. This report highlights the deployment of the Ralstonia Wilt Dashboard and provides four case studies that address focused, scientific questions (https://ralstoniadashboard.shinyapps.io/RalstoniaWiltDashboard/).

Antimicrobial-resistant (AMR) bacteria are an increasing concern for human and animal medicine. As a result, biosecurity measures such as cleaning and disinfection are becoming heavily relied upon to eradicate and control AMR pathogens. However, evidence of co- and cross-resistance between antimicrobials and disinfectants is rising. The influence of AMR on disinfectant tolerance is poorly understood for pathogens of veterinary and public health importance. Therefore, this study aimed to compare disinfectant tolerance of fluoroquinolone-resistant Campylobacter jejuni, livestock-associated methicillin-resistant Staphylococcus aureus, multi-drug-resistant Escherichia coli and vancomycin-resistant Enterococcus faecium, with their antibiotic-susceptible counterparts. In vitro disinfectant efficacy was assessed, in the presence of organic matter, against a panel of eight disinfectants from six classes. The disinfectant efficacy varied widely depending on bacterial species and disinfectant class. Furthermore, approved disinfectant concentrations were not always deemed effective. All four bacterial species were typically most susceptible to aldehyde and/or quaternary ammonium compound-based products. Mixed evidence was found to suggest a role of AMR in disinfectant tolerance; no role of AMR was identified in E. coli, C. jejuni or E. faecium, whereas a potential role was identified in S. aureus.