Blau Khald, Gallert Claudia
Department of Microbiology-Biotechnology, Faculty of Technology, University of Applied Sciences Emden/Leer, Constantiaplatz 4, 26723 Emden, Germany.
Department of Botany, Faculty of Sciences, University of Gharyan, Gharyan P.O. Box 81006, Libya.
Antibiotics (Basel). 2025 Jul 4;14(7):678. doi: 10.3390/antibiotics14070678.
BACKGROUND/OBJECTIVES: is a "One Health" pathogen and a cause of antibiotics-associated diarrhea and pseudomembranous colitis. Mobile genetic elements (MGEs) have been documented in the genomes of clinical strains; however, the presence of MGEs in environmental strains remains poorly characterized. Thus, the present study was conducted with the objective of identifying the prevalence of MGEs, including mobilizable transposons (MTns), conjugative transposons (CTns), plasmids, and insertion sequences, in whole genome sequences (WGSs) of environmental isolates.
The analysis of MGEs was conducted using 166 WGSs obtained from strains isolated from various environmental sources contaminated with feces. The MGEs were identified using bioinformatic tools.
A total of 48.2% (80/166) of the studied genomes were identified to harbor nine transposons, including Tn, Tn-like, Tn, Tn, Tn, Tn, Tn, Tn, or Tn-like. The majority of MTns and CTns could be found within sequence types ST11, ST3, and ST35. The results demonstrated close genetic relatedness among the studied genomes, the array of antimicrobial resistance (AMR) genes, such as , , and , and the presence of CTns. Furthermore, the analysis revealed that 24.7% (41/166) of the genome sequences of isolates were associated with various predominant plasmid groups, including pCD6, pCD-ECE4-6, pCD-WTSI1-4, pCDBI1, and pCd1_3, which belonged to 16 different sequence types. Furthermore, several plasmids were identified as harboring the prophage phiCDHM19.
The results of the current study suggest that the identified plasmids are abundant and may encode functions that are relevant to physiology. The genomes of strains examined contain closely related CTns, suggesting that horizontal transfer of AMR is important in this species or other bacterial species. Further research is required to ascertain the effect of these genetic elements and their transferability on the biology of .
背景/目的：是一种“同一健康”病原体，也是抗生素相关性腹泻和伪膜性结肠炎的病因。移动遗传元件（MGEs）已在临床菌株的基因组中被记录；然而，环境菌株中MGEs的存在情况仍知之甚少。因此，本研究旨在确定环境分离株全基因组序列（WGSs）中MGEs的流行情况，包括可移动转座子（MTns）、接合转座子（CTns）、质粒和插入序列。
使用从受粪便污染的各种环境来源分离的菌株获得的166个WGSs对MGEs进行分析。使用生物信息学工具鉴定MGEs。
共鉴定出48.2%（80/166）的研究基因组含有9种转座子，包括Tn、Tn样、Tn、Tn、Tn、Tn、Tn、Tn或Tn样。大多数MTns和CTns可在序列类型ST11、ST3和ST35中找到。结果表明，所研究的基因组、一系列抗菌抗性（AMR）基因（如、和）以及CTns的存在之间存在密切的遗传相关性。此外，分析显示，24.7%（41/166）的分离株基因组序列与各种主要质粒组相关，包括pCD6、pCD-ECE4-6、pCD-WTSI1-4、pCDBI1和pCd1_3，它们属于16种不同的序列类型。此外，还鉴定出几种质粒含有前噬菌体phiCDHM19。
本研究结果表明，所鉴定的质粒丰富，可能编码与生理学相关的功能。所检测的菌株基因组含有密切相关的CTns，表明AMR的水平转移在该物种或其他细菌物种中很重要。需要进一步研究以确定这些遗传元件及其可转移性对生物学的影响。
