YhjX Regulates the Growth of Escherichia coli in the Presence of a Subinhibitory Concentration of Gentamicin and Mediates the Adaptive Resistance to Gentamicin

Frontiers in Microbiology

卷:10

Huifang Li¹  Xiaojuan Zhu¹  Gulibaier Nuer¹  Shuqin Zhou²  Huifang Zhou³  Yuanchun Huang⁴  Qing Peng⁵  Shao Li⁵  Haiyan Li⁶  Fen Yao⁶  Xiaoguang Zou⁷  Jianhua Wu⁸  Yijing Zhuang⁹ 

[1] Department of Anesthesiology, First People’s Hospital of Kashi, Kashi, China;

[2] Department of Anesthesiology, Zhujiang Hospital, Southern Medical University, Guangzhou, China;

[3] Department of Clinical Laboratory, First People’s Hospital of Kashi, Kashi, China;

[4] Department of Clinical Laboratory, The First Affiliated Hospital of Shantou University Medical College, Shantou, China;

[5] Department of Hepatobiliary II, Zhujiang Hospital of Southern Medical University, Guangzhou, China;

[6] Department of Pharmacology, Shantou University Medical College, Shantou, China;

[7] Department of Pharmacy, First People’s Hospital of Kashi, Kashi, China;

[8] Department of Science and Education, First People’s Hospital of Kashi, Kashi, China;

[9] Department of Science and Education, The First Affiliated Hospital of Shantou University Medical College, Shantou, China;

关键词: Escherichia coli;    adaptive resistance;    gentamicin;    YjhX;    bacterial growth;   

DOI  :  10.3389/fmicb.2019.01180

来源: DOAJ

【 摘 要 】

The mechanisms of adaptive resistance of Escherichia coli to aminoglycosides remain unclear. Our RNA-Seq study found that expression of yhjX was markedly upregulated during initial exposure to subinhibitory concentrations of gentamicin. The expression of yhjX was then downregulated dramatically during a second exposure to gentamicin compared to the first exposure. YhjX encodes a putative transporter of the major facilitator superfamily, which is known to be the sole target of the YpdA/YpdB two-component system, the expression of which is highly and specifically induced by pyruvate. To investigate the effect of yhjX on the adaptive resistance of E. coli, in the present study, we constructed yhjX deletion and complemented strains of E. coli ATCC25922. Changes in extracellular pyruvate levels of wide-type and yhjX mutant were measured to determine whether YhjX functions as a pyruvate transporter. The results showed that yhjX deletion improved the growth of E. coli in medium containing subinhibitory concentrations of gentamicin. The yhjX deletion mutant did not exhibit adaptive resistance to subinhibitory concentrations of gentamicin. YhjX might not function as a pyruvate efflux pump in E. coli but was associated with the decrease following a sharp increase in the extracellular pyruvate level. Our findings indicate that yhjX regulates the growth of E. coli in the presence of a subinhibitory concentration of gentamicin and mediates the adaptive resistance to gentamicin.

【 授权许可】

Unknown