耐甲氧西林金黄色葡萄球菌中prsA和vraTS调控系统在面对苯唑西林应激时的转录分析。

Transcriptional analysis of prsA and vraTS regulatory system in methicillin resistant Staphylococcus aureus against oxacillin stress.

作者信息

Bhowmik Deepshikha, Das Bhaskar Jyoti, Hazarika Monalisha, Chanda Debadatta Dhar, Bhattacharjee Amitabha

机构信息

Department of Microbiology, Assam University, Silchar, Assam, India.

Department of Microbiology, Silchar Medical College and Hospital, Silchar, Assam, India.

出版信息

Indian J Med Microbiol. 2022 Jan-Mar;40(1):57-60. doi: 10.1016/j.ijmmb.2021.10.009. Epub 2021 Nov 10.

DOI:10.1016/j.ijmmb.2021.10.009

Abstract

PURPOSE

The prsA and vraTSR regulatory systems play a unique role in methicillin resistance by modifying the peptidoglycan cell wall PBP2 and involving cell wall stress response in Staphylococcus aureus. This study was designed to observe the transcriptional response of prsA and vraTSR system under oxacillin stress in S.aureus.

METHODS

In this study, three clinical isolates of Staphylococcus aureus and a laboratory strain were examined. All the isolates were tested for mecA gene by PCR assay and were also tested for prsA, vraT, vraS and vraR gene. The transcriptional responses of the prsA gene along with the vraTSR regulatory system in these isolates was observed under normal conditions and exposed to 2 μg/ml and 4 μg/ml of oxacillin stress by quantitative real-time PCR assay.

RESULTS

The result of transcriptional analysis confirmed that under oxacillin stress, the expressions of vraS and vraT are increased with the increase in the concentration of oxacillin. However, prsA has shown no significant expression under oxacillin stress.

CONCLUSION

Although prsA did not show any specific expressional pattern, the study highlights the role of vraS and vraT regulatory system in conferring a methicillin-resistant phenotype when exposed to subinhibitory concentrations of oxacillin, which could act as a potential target for the next-generation antimicrobials.

摘要

目的

prsA和vraTSR调控系统通过修饰肽聚糖细胞壁PBP2并参与金黄色葡萄球菌的细胞壁应激反应，在耐甲氧西林方面发挥独特作用。本研究旨在观察金黄色葡萄球菌在苯唑西林应激下prsA和vraTSR系统的转录反应。

方法

本研究检测了3株金黄色葡萄球菌临床分离株和1株实验室菌株。通过PCR检测所有分离株的mecA基因，并检测prsA、vraT、vraS和vraR基因。通过定量实时PCR检测在正常条件下以及暴露于2μg/ml和4μg/ml苯唑西林应激下这些分离株中prsA基因以及vraTSR调控系统的转录反应。

结果

转录分析结果证实，在苯唑西林应激下，vraS和vraT的表达随着苯唑西林浓度的增加而增加。然而，prsA在苯唑西林应激下未显示出显著表达。

结论

尽管prsA未显示出任何特定的表达模式，但该研究突出了vraS和vraT调控系统在暴露于亚抑菌浓度苯唑西林时赋予耐甲氧西林表型中的作用，这可能成为下一代抗菌药物的潜在靶点。