Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae have been isolated from human patients in many countries across the globe but rarely in Saudi Arabia. Here we provide the genomic characterization of the first KPC-producing K. pneumoniae isolated from the urine of a patient in Riyadh, Saudi Arabia, who had a recent travel history to Egypt involving a medical procedure. Presence of KPC-encoding gene initially detected with the Xpert Carba-R assay was confirmed by traditional PCR. Susceptibility testing using the VITEK 2 system, E-test and microbroth dilution methods showed that the K. pneumoniae isolate, namely SA01_KPC-2, was resistant to all antibiotics except colistin and ceftazidime/avibactam. Whole-genome sequencing (WGS), performed on the Illumina Miseq instrument, identified the isolate as sequence type (ST) 383 and serotype KL30-D1 O1v2. Genome assembly of SA01_KPC-2 indicated the presence of two plasmids. Plasmid pSA01_KPC-2, of approximately 45.9 kb in size, harbored the blaKPC-2 flanked by ISKpn27 and ISKpn6 and had a backbone similar to published KPC-carrying IncX6 plasmids. The second plasmid pSA01_incHIB1, a derivative of published 372-kb plasmid pKpvST383, carried genes encoding virulence factors and resistance to five classes of antibiotics. The isolation of the first KPC producer in Saudi Arabia requires high attention and rapid interventions to prevent further spread.

Uropathogenic Escherichia coli (UPEC) is the most common cause of urinary tract infections (UTIs) in hospitalised and non-hospitalised patients. Genomic analysis was used to gain further insight into the molecular characteristics of UPEC isolates from Saudi Arabia. A total of 165 isolates were collected from patients with UTIs between May 2019 and September 2020 from two tertiary hospitals in Riyadh, Saudi Arabia. Identification and antimicrobial susceptibility testing (AST) were performed using the VITEK system. Extended-spectrum β-lactamase (ESBL)-producing isolates (n = 48) were selected for whole genome sequencing (WGS) analysis. In silico analysis revealed that the most common sequence types detected were ST131 (39.6%), ST1193 (12.5%), ST73 (10.4%), and ST10 (8.3%). Our finding showed that bla_CTX-M-15 gene was detected in the majority of ESBL isolates (79.2%), followed by bla_CTX-M-27 (12.5%) and bla_CTX-M-8 (2.1%). ST131 carried bla_CTX-M-15 or bla_CTX-M-27, and all ST73 and ST1193 carried bla_CTX-M-15. The relatively high proportion of ST1193 in this study was notable as a newly emerged lineage in the region, which warrants further monitoring.

Adipocytes play a critical role in maintaining a healthy systemic metabolism by storing and releasing energy in the form of fat and helping to regulate glucose and lipid levels in the body. Adipogenesis is the process through which pre-adipocytes are differentiated into mature adipocytes. It is a complex process involving various transcription factors and signaling pathways. The dysregulation of adipogenesis has been implicated in the development of obesity and metabolic disorders. Therefore, understanding the mechanisms that regulate adipogenesis and the factors that contribute to its dysregulation may provide insights into the prevention and treatment of these conditions. RNA-binding motif single-stranded interacting protein 1 (RBMS1) is a protein that binds to RNA and plays a critical role in various cellular processes such as alternative splicing, mRNA stability, and translation. RBMS1 polymorphism has been shown to be associated with obesity and type 2 diabetes, but the role of RBMS1 in adipose metabolism and adipogenesis is not known. We show that RBMS1 is highly expressed during the early phase of the differentiation of the murine adipocyte cell line 3T3-L1 and is significantly upregulated in the adipose tissue depots and adipocytes of high-fat-fed mice, implying a possible role in adipogenesis and adipose metabolism. Knockdown of RBMS1 in pre-adipocytes impacted the differentiation process and reduced the expression of some of the key adipogenic markers. Transcriptomic and proteomic analysis indicated that RBMS1 depletion affected the expression of several genes involved in major metabolic processes, including carbohydrate and lipid metabolism. Our findings imply that RBMS1 plays an important role in adipocyte metabolism and may offer novel therapeutic opportunity for metabolic disorders such as obesity and type 2 diabetes.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) represents a critical global health threat, with ST101 identified as a major circulating clone in Saudi Arabia. We used whole genome sequencing and plasmid reconstruction to investigate the molecular characteristics of CRKP ST101 isolates from Saudi Arabia (2018–2021), analyzing antimicrobial resistance genes (ARGs), virulence factors, and plasmid structure and replicon types. Clinical isolates were obtained from the Ministry of National Guard Health Affairs (MNGHA) hospitals in Saudi Arabia between 2018 and 2021. Whole-genome sequencing was performed using the Illumina MiSeq^® platform, followed by comprehensive bioinformatic analysis of ARGs, virulence factors, and plasmid content. All ten isolates belonged to ST101 and harbored extensive antimicrobial resistance (AMR) and virulence determinants. Nine isolates (90%) carried bla_OXA-48, with three co-harboring bla_NDM-1, representing dual-carbapenemase producers. These carbapenemase genes were located on plasmids with distinct replicon types, including IncL/M, IncHI1B/IncFIB, and IncFIA/IncR. All isolates were multidrug-resistant (MDR), with half classified as extensively drug-resistant (XDR). Four isolates exhibited hypervirulent profiles, harboring aerobactin and yersiniabactin siderophores. This study provides comprehensive genomic characterization of CRKP ST101 in Saudi Arabia, revealing complex resistance mechanisms mediated by diverse plasmid types. The findings highlight the importance of genomic surveillance to track the evolution and dissemination of high-risk MDR and XDR lineages and inform targeted infection control strategies.

Pseudomonas otitidis is a rare and unique species among the Pseudomonas genus that has not been previously reported as a cause of male genitourinary tract infection. In this report, we describe a case of a 20-year-old immunocompetent male who presented with recurrent epididymo-orchitis, which was initially misidentified as Vibrio vulnificus and treated successfully. The causative agent could not be identified appropriately using the available routine methods, but a final identification was established using 16S rRNA targeted sequencing followed by whole-genome sequencing.