Main menu

Identification of novel tetracycline resistance gene tet(X14) and its co-occurrence with tet(X2) in a tigecycline-resistant and colistin-resistant Empedobacter stercoris


Tigecycline is one of the last-resort antibiotics to treat severe infections. Recently, tigecycline resistance has sporadically emerged with an increasing trend, and Tet(X) family represents a new resistance mechanism of tigecycline. In this study, a novel chromosome-encoded tigecycline resistance gene, tet(X14), was identified in a tigecycline-resistant and colistin-resistant Empedobacter stercoris strain ES183 recovered from a pig fecal sample in China. Tet(X14) shows 67.14-96.39% sequence identity to the other variants [Tet(X) to Tet(X13)]. Overexpression of Tet(X14) in Escherichia coli confers 16-fold increase in tigecycline MIC (from 0.125 to 2 mg/L), which is lower than that of Tet(X3), Tet(X4) and Tet(X6).

Structural modelling predicted that Tet(X14) shared a high homology with the other 12 variants with RMSD value from 0.003 to 0.055, and Tet(X14) can interact with tetracyclines by a similar pattern as the other Tet(X)s. tet(X14) and two copies of tet(X2) were identified on a genome island with abnormal GC content carried by the chromosome of ES183, and no mobile genetic elements were found surrounding, suggesting that tet(X14) might be heterologously obtained by ES183 via recombination. Blasting in Genbank revealed that Tet(X14) was exclusively detected on the chromosome of Riemerella anatipestifer, mainly encoded on antimicrobial resistance islands. E. stercoris and R. anatipestifer belong to the family Flavobacteriaceae, suggesting that the members of Flavobacteriaceae maybe the major reservoir of tet(X14).

Our study reports a novel chromosome-encoded tigecycline resistance gene tet(X14). The expanded members of Tet(X) family warrants the potential large-scale dissemination and the necessity of continuous surveillance for tet(X)-mediated tigecycline resistance.

Authors: Yingying Cheng, Yong Chen, Yang Liu, Yuqi Guo, Yanzi Zhou, Tingting Xiao, Shuntian Zhang, Hao Xu, Yunbo Chen, Tongling Shan, Yonghong Xiao, Kai Zhou

入門

MinION Starter Packを購入 ナノポア製品の販売 シークエンスサービスプロバイダー グローバルディストリビューター

ナノポア技術

ナノポアの最新ニュースを購読 リソースと発表文献 Nanopore Communityとは

Oxford Nanoporeについて

ニュース 会社沿革 持続可能性 経営陣 メディアリソース & お問い合わせ先 投資家向け パートナー向け Oxford Nanopore社で働く 現在の募集状況 営業上の情報 BSI 27001 accreditationBSI 90001 accreditationBSI mark of trust
Japanese flag