Biology subjects

McKeown, C.

Publications and source records attributed to McKeown, C..

3 recordsLinked to original sources

bioRxiv2026

Novel Class B2 and C β-lactamases harboured by Pseudomonas spp. wastewater isolates

IntroductionAntimicrobial resistance has existed in the environment long before its rapid emergence and detection in clinically relevant pathogens. Studying the resistance of environmental bacterial strains may allow novel resistance mechanisms to be identified before they appear in pathogenic strains. Gap StatementSearching for antimicrobial resistance genes in environmental bacteria represents an understudied research area compared to resistance within clinically relevant pathogens. AimTo evaluate resistance genes present within environmental non-aeruginosa Pseudomonas spp. isolates. MethodologyWe screened a set of bacterial isolates from untreated wastewater from Liverpool, UK, for the presence of extended spectrum {beta}-lactamases and carbapenemases. A sub-set of three resistant Pseudomonas spp. isolates were selected for whole-genome sequencing. We performed minimum inhibitory concentration assays against several {beta}-lactams, and ectopic expression of four novel resistance genes within Escherichia coli. ResultsHere, we report the discovery of novel class C {beta}-lactamase genes blaPFL7, blaPFL8 and blaPFL9, as well as a novel subclass B2 metallo-{beta}-lactamase blaPFM5 present within these strains. The class C genes encoded proteins with between 61-71% amino acid identity to the closest known match, blaPFL-1. These novel {beta}-lactamases degraded the cephalosporin nitrocefin and confer piperacillin and ceftazidime resistance to susceptible Escherichia coli when ectopically expressed. The {beta}-lactamase inhibitor tazobactam was effective at inhibiting these enzymes. The sub-class B2 metallo-{beta}-lactamase had 88% amino acid identity to its closet match blaPFM-1 and conferred carbapenem resistance to susceptible E. coli. The {beta}-lactamase inhibitors relebactam, vaborbactam, xeruborbactam and captopril had no impact on the carbapenem resistance phenotype. Analogues of all these novel genes (>95% nucleotide sequence identity) were identified within publicly available whole-genome sequencing data, suggesting they are found sporadically. ConclusionOur analysis adds to the growing number of {beta}-lactamase genes found from environmental Pseudomonas spp. and suggests that continued surveillance of this environmental reservoir for novel, clinically relevant, {beta}-lactamase genes is warranted.

microbiology↗

bioRxiv2025

An evaluation of screening methods for the detection of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae in environmental samples from healthcare settings

Drug-resistant infections with extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-E) are increasingly problematic, especially in healthcare settings. ESBL-E infections lead to a worse treatment outcome and often require escalating antibiotic treatment to reserve antibiotics such as carbapenems. Understanding how these bacteria are transmitted within healthcare settings is complex and not well understood, but it is a requirement for effective infection prevention and control strategies. To what extent environmental ESBL-E reservoirs contribute to transmission is unclear. To accurately capture these reservoirs, laboratory processing of environmental samples needs to be optimised to reliably detect ESBL-E, which is challenging because they can be scarce and part of complex microbial communities. Here, we assessed screening methods for the detection of ESBL-producing Escherichia coli (ESBL-Ec) and Klebsiella pneumoniae (ESBL-Kp) from environmental swabs taken from healthcare settings, testing different swab types, pre-enrichment conditions and selective agars. We show that a pre-enrichment of 18 hours significantly increased the recovery of 3GC-resistant gram-negatives. The choice of selective agar impacted the number of ESBL-Ec and ESBL-Kp detected. This also affected the number of samples requiring additional species confirmation, which is costly and time-consuming. For our use case and by considering additional factors such as cost and practical aspects, Membrane Lactose Glucuronide Agar supplemented with cefotaxime performed best for the combined detection of ESBL-Ec and ESBL-Kp. Our work will guide environmental surveillance of ESBL-E by providing optimised methods for laboratory processing of environmental samples from healthcare settings.

microbiology↗

bioRxiv2024

Student experiences with an interactive 3D immersive biotechnology simulation and its impact on motivational beliefs

The development and use of virtual laboratories to augment traditional in-person skills training continues to grow. Virtual labs have been implemented in a number of diverse educational settings, which have many purported benefits including their adaptability, accessibility, and repeatability. However, few studies have evaluated the impact of virtual laboratories outside of academic achievement and skills competencies, especially in biotechnology. In this study, an interdisciplinary team of content experts, video game researchers, instructional designers, and assessment experts developed a 3D immersive simulation designed to teach novice scientists the technical skills necessary to perform sterile mammalian cell culture technique. Unique to the simulation development process is the recreation of an immersive experience through the capture of details in the real-world lab where participants have the freedom of choice in their actions, while receiving immediate feedback on their technical skills as well as procedural execution. However, unlike an in-person laboratory course, students are able to iterate and practice their skills outside of class time and learn from their mistakes. Using a mixed-methods study design, over the course of two semesters we evaluated student attitudes of the simulation and their science motivational beliefs including self-efficacy and science identity after engaging with the simulation prior to the physical laboratory. Our results show that students science identity remained unchanged while their science self-efficacy increased. Furthermore, students had positive perceptions of the benefits of the virtual simulation. These data suggest that the virtual cell culture simulation can be a useful pedagogical training tool to bolster students motivational beliefs that is both accessible and easy to implement.

scientific communication and education↗