Search Results (4)

Klebsiella pneumoniae (Kp) is a leading cause of hospital-acquired infections representing a growing threat driven by emerging multidrug resistance (MDR) and hypervirulence. In this study, we aim to characterise the genomic and epidemiological landscape of Kp in a Portuguese regional hospital (Braga) lacking prior genomic data. We performed whole-genome sequencing of 115 Kp isolates collected from colonisation and infection cases. Phylogenetic, resistance, and virulence profiles were integrated with clinical and epidemiological data. Genomic analysis revealed high diversity, with 83.5% of isolates forming evolutionary clusters. Several novel sequence types (STs), as ST2623 and ST1562, were detected for the first time in Portugal to our knowledge. ST45, uncommonly associated with carbapenem resistance, emerged as dominant with multiple blaKPC-3-positive isolates. Results suggest active transmission of carbapenem resistance genes. One hypervirulent carbapenem-resistant ST13 warrants careful surveillance. Virulence-associated yersiniabactin was common (66.9%) but other hypervirulence loci were rare. Epidemiologically, MDR-Kp was associated with older hospitalised patients with prior antibiotic use and invasive procedures, while community-acquired infections were genetically diverse and affected younger patients with comorbidities. An unusually low number of respiratory infections was observed, likely reflecting strict COVID-19 mitigation measures. Although widespread dissemination of hypervirulent or MDR clones was not evident, the emergence of high-risk lineages and the detection of ongoing gene transmission episodes underscore the need for ongoing genomic surveillance. Immediate mitigation strategies could include reducing device use and hospital transfers, given the high prevalence of colonisation. Full article

Background: Mobile antimicrobial resistance genes (ARGs) on plasmids or other elements enable Salmonella Typhimurium to spread resistance across hosts and environments. The emergence of multi-drug resistance (MDR) Salmonella Typhimurium has raised global concern, yet little is reported about these mobile elements from the Thailand pork supply chain, where this risk of transfer to humans remains largely uncharacterized. Methods: Between March 2023 and February 2024, 25 S. Typhimurium isolates were collected from pig carcasses in slaughterhouses and pork swabs from retail markets in northeastern Thailand. Nine representative isolates, sampled across three seasons, were subjected to Illumina whole-genome sequencing. Assemblies were analyzed for sequence types, phylogenetic relationships, antimicrobial resistance (AMR) determinants, plasmid replicons and mobilization features, functional annotation based on COG (Clusters of Orthologous Groups of proteins) classification, and comparative genomics against a reference strain. Results: Genome assemblies ranged from 4.76 to 5.00 Mb with consistent GC (guanine-cytosine) content (52.0–52.2%). Phylogenetic analysis revealed three sequence types: ST34 (77.8%), ST19, and ST1543. ST34 isolates displayed the broadest AMR gene repertoires, carrying tetracycline (tetA/tetB), sulfonamide (sul1/sul2/sul3), aminoglycoside (aadA, aph(6)-Id, aph(3″)-Ib), phenicol (floR, catA1), and β-lactam (bla_TEM-1B) genes, whereas non-ST34 isolates harbored fewer determinants. ARGs frequently co-localized with IncQ1 and Col-type plasmid replicons, MOB_H/MobA relaxases (enzymes that initiate plasmid transfer), and conjugation modules (type IV secretion and coupling proteins), often alongside virulence loci and metal resistance operons. Functional annotation showed highly conserved metabolic and housekeeping functions, while comparative genomics confirmed >90% core genome conservation, with variability concentrated in genomic islands encoding hypothetical proteins. These genomic patterns were inferred from a limited WGS dataset (nine isolates) and should therefore be considered exploratory and require confirmation in larger collections. Conclusions: Multi-drug resistant ST34 Salmonella Typhimurium predominated in the northeastern Thailand pork supply chain, with diverse resistance genes carried on IncQ1/Col-type plasmids linked to MOB_H relaxases and conjugation modules. The stability of these mobilizable elements underscores their role in sustaining MDR traits and highlights the risk of foodborne AMR transmission, reinforcing the need for continuous genomic surveillance under a One Health framework. Full article

The Prunus genus encompasses a group of economically important and closely related crops, sharing an essentially common genome and, thereby, a high level of conserved and transferable microsatellite (SSR) loci. In Southern Italy, many of the local and/or neglected varieties are abandoned and at risk of extinction due to the high degree of urbanization and agricultural intensification, despite their value as genetic resources for crop improvement. This research aimed to genetically and morphologically characterize the traditional apricot (P. armenica) and peach (P. persica) germplasms collected in old family orchards. Most of the official descriptor categories were scored, thus revealing a rather high level of phenotypic variation in both collections. Genetic data allowed the discovery of diversity masked by morphological traits. Genotyping in 15 and 18 SSRs, eight of which were transferable across both species, showed an average polymorphic informativeness (PIC) of 0.44 and 0.59 for apricot and peach, respectively, and a total of 70 and 144 alleles. A reliable identification of each genotype was achieved, and the presence of possible mislabeling and/or erroneous denominations was solved. These results are encouraging for the valorization of the still poorly explored Italian Prunus germplasm, with significant economic consequences for bioresource conservation and management. Full article

The Arabian Peninsula, located at the nexus of Africa, Europe, and Asia, was implicated in early human migration. The Arab population is characterized by consanguinity and endogamy leading to inbreeding. Global genome-wide association (GWA) studies on metabolic traits under-represent the Arab population. Replicability of GWA-identified association signals in the Arab population has not been satisfactorily explored. It is important to assess how well GWA-identified findings generalize if their clinical interpretations are to benefit the target population. Our recent study from Kuwait, which performed genome-wide imputation and meta-analysis, observed 304 (from 151 genes) of the 4746 GWA-identified metabolic risk variants replicable in the Arab population. A recent large GWA study from Qatar found replication of 30 GWA-identified lipid risk variants. These complementing studies from the Peninsula increase the confidence in generalizing metabolic risk loci to the Arab population. However, both the studies reported a low extent of transferability. In this review, we examine the observed low transferability in the context of differences in environment, genetic correlations (allele frequencies, linkage disequilibrium, effect sizes, and heritability), and phenotype variance. We emphasize the need for large-scale GWA studies on deeply phenotyped cohorts of at least 20,000 Arab individuals. The review further presents GWA-identified metabolic risk variants generalizable to the Arab population. Full article