Genomic Diversity of the <i>tet</i>(X)-Positive <i>Myroides</i> Species

The rapid spread of <i>tet</i>(X) genes capable of inactivating tigecycline represents a critical challenge to global public health. This study aims to explore the distribution, genetic diversity, and transferability of <i>tet</i>(X) genes in <i>Myroides</i>, a ge...

Full description

Saved in:
Bibliographic Details
Main Authors: Chong Chen, Taotao Wu, Jing Liu, Yilin Lv
Format: Article
Language:English
Published: MDPI AG 2025-05-01
Series:Microorganisms
Subjects:
Online Access:https://www.mdpi.com/2076-2607/13/6/1180
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The rapid spread of <i>tet</i>(X) genes capable of inactivating tigecycline represents a critical challenge to global public health. This study aims to explore the distribution, genetic diversity, and transferability of <i>tet</i>(X) genes in <i>Myroides</i>, a genus of Gram-negative bacteria increasingly implicated in multidrug-resistant (MDR) bacterial infections. From 2021 to 2024, 646 samples of chicken, sheep, soil, and water were randomly collected, yielding nine chicken-derived <i>tet</i>(X)-positive <i>Myroides</i> sp. strains in Shandong, China. All of them were MDR to tetracycline, ceftazidime, gentamicin, amikacin, colistin, ciprofloxacin, gatifloxacin, and trimethoprim-sulfamethoxazole, with elevated minimum inhibitory concentrations (MICs) for tigecycline, florfenicol, and macrolides, but exhibited susceptibility to meropenem (100%), ampicillin-sulbactam (66.7%), and cefotaxime (33.3%). A genomic analysis of the isolates and 86 public <i>tet</i>(X)-positive <i>Myroides</i> genomes revealed the widespread distribution of <i>tet</i>(X) and macrolide-inactivating <i>estT</i> genes across 12 <i>Myroides</i> species, including 7 novel species. Eight <i>tet</i>(X) and eight estT variants were identified, half of which were novel. The phylogenetic analysis highlighted interspecies transmission risks, with IS<i>CR2</i>-mediated transposons of <i>tet</i>(X6) and <i>estT-2</i> across <i>Myroides</i>, <i>Riemerella</i>, <i>Empedobacter</i>, <i>Providencia</i>, <i>Acinetobacter</i>, and <i>Proteus</i> species. These findings illuminate the genomic diversity driving antibiotic resistance in understudied bacterial taxa, with implications for global One Health strategies.
ISSN:2076-2607