Background.Listeria monocytogenes is a common foodborne organism identified as a causative agent of multiple clinical conditions in unique circumstances such as pregnancy and immunocompromise. It is a Gram-positive rod and a facultative anaerobic organism. This paper presents a study over a timeline of 5 years in retrospect and explores the incidence of listeriosis amongst patients of different age groups, along with its associated risk factors and clinical outcomes.Materials and methods. This study was conducted in retrospect from June 2019 to June 2024 at Shifa International Hospital, Islamabad. Ninety-seven cases of listeriosis were identified. These cases were culture-positive listeriosis where the pathogen was isolated from various samples such as blood and cerebrospinal fluid. Important risk factors associated with the clinical presentations were also documented, which included diabetes mellitus, chronic kidney disease and malignancy. The mean±sd was calculated for the continuous variable. Frequency and percentage were calculated for categorical variables. Chi-square tests were performed to assess associations with mortality and foetal outcomes.Results. A total of 97 culture-confirmed listeriosis cases, comprising 44 (45.5%) males and 53 (54.6%) females, were obtained. Fifteen of the females were pregnant. Fever was the most common presenting symptom across all groups, with pregnant patients also reporting abdominal pain, vomiting and foetal complications, while non-pregnant patients showed a wider range, including neurological, respiratory and gastrointestinal complaints. Of the 97 patients, 86 had comorbidities – most commonly hypertension and diabetes – while 15 total adult deaths occurred. Eight pregnancies resulted in foetal losses. Descriptive trends in pregnant patients suggested worse foetal outcomes with higher C-reactive protein, total leukocyte count and maternal comorbidities. Ampicillin-based regimens were the most frequently used treatments, and all isolates were sensitive to the tested antibiotics.Conclusion. This study highlights how listeriosis poses substantial morbidity and mortality risk, especially in pregnant cases. There is also a critical data gap, emphasizing the need for better diagnostic strategies, timely and targeted interventions, awareness of the clinical team and public health surveillance to reduce the burden of this often-overlooked infection in Pakistan.

This Technical Resource presents genome sequence data for three strains of the bacterial pathogen Xanthomonas euvesicatoria pv. euvesicatoria (Xeu) collected in Serbia. We isolated these strains from pepper crops showing bacterial spot symptoms in 2016 at the municipality of Irig, in the Srem district. The presented data comprise raw sequencing reads and annotated, contig-level genome assemblies. We checked for the presence of sequences of known type-3 secretion system (T3SS) effector genes and plasmid-like sequences. Phylogenomic reconstruction revealed that the three strains fell in the same clade within Xeu. Strain X13 is most closely related to strain 66b, collected in Bulgaria in 2012. Strains X22 and X31 are most closely related to Tu-10 collected in the Southeastern Anatolia region of Türkiye in 2020. In common with other members of the clade, all three strains share a 75 kb plasmid that carries T3SS effector genes avrBs3, xopBA, xopAQ and xopE. Additionally, strain X13 shares extensive sequence similarity to the pXCV183 plasmid, including T3SS effector gene xopAX, and shares extensive sequence similarity with plasmid pXap41, including T3SS effector gene xopE3. This difference in plasmid content might contribute to the observed difference in virulence among the Serbian Xeu strains. The three Serbian strains lack a 31 kb plasmid, pLMG730.4, that is seen in several Vietnamese and Canadian strains within this clade of Xeu. The data presented will be a useful resource for future molecular epidemiology and genomic surveillance of this pathogen in the Balkan region, augmenting the previously available draft genome sequences of Xeu strains 66b (Bulgaria) and 83M (North Macedonia).

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/).

Background. Carbapenem and third-generation cephalosporin (3GC) resistance among Gram-negative bacteria poses a serious threat to human and animal health. This study aimed to identify and characterize carbapenem- and 3GC-resistant Enterobacterales isolated from poultry in Lusaka Province, Zambia.Methods. Ninety pooled cloacal samples were collected from market-ready broiler chickens in the Chongwe and Chilanga districts of Lusaka Province. The isolates were screened for 3GC and carbapenem resistance using the disc diffusion and broth microdilution methods. PCR and Sanger sequencing were performed for species identification and detection of β-lactamase-encoding (bla) genes, including blaCTX-M, blaTEM, blaOXA-1 and blaSHV. Hierarchical clustering was used to assess phenotypic and genotypic relationships.Results. A total of 83 3GC-resistant Gram-negative isolates were recovered, of which 12% were also carbapenem resistant. Escherichia coli was the most prevalent species, followed by Klebsiella pneumoniae and Enterobacter spp., then Pseudomonas aeruginosa, other Pseudomonas spp., Acinetobacter baumannii, Citrobacter freundii and Aeromonas caviae. Multidrug resistance occurred in 84.3% of the isolates, with the highest resistance to ampicillin, tetracycline and co-trimoxazole. Overall, 80.7% of the isolates harboured at least one of the four tested bla genes, with blaCTX-M and blaTEM being the most common. Hierarchical clustering revealed that isolates from both districts shared similar phenotypic and genotypic resistance patterns.Conclusions. The presence of multidrug- and carbapenem-resistant Enterobacterales from poultry highlights the emergence of carbapenem resistance in Zambia’s food production sector. The detection of imipenem-resistant isolates indicates the potential for transmission of resistance genes between animals and humans. These findings underscore the need for prudent antimicrobial use, strengthened stewardship and a One Health surveillance approach to contain the spread of carbapenem resistance genes.