布鲁氏菌属在接触亚抑菌浓度庆大霉素和酸胁迫后，II 型 TA 系统基因的表达。
The expression of type II TA system genes following exposure to the sub-inhibitory concentration of gentamicin and acid stress in Brucella spp.
机构信息
Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Microbial Biotechnology Research Center, Iran University of Medical Science, Tehran, Iran.
Department of Medical Microbiology, Faculty of Medicine, Ilam University of Medical Sciences, Ilam, Iran; Clinical Microbiology Research Center, Ilam University of Medical Sciences, Iran.
出版信息
Microb Pathog. 2020 Jul;144:104194. doi: 10.1016/j.micpath.2020.104194. Epub 2020 Apr 11.
BACKGROUND
Brucellosis is one of the most common diseases that afflicts both humans and animals. Bacteria react to stress conditions using different mechanisms one of which is Toxin-Antitoxin (TA) systems. It is believed that the Toxin-Antitoxin (TA) systems have a key role in the chronicity of the disease. This study investigated the expression of TA system genes under acid and antibiotic stresses in Brucella spp.
METHODS
Fifty Brucella isolates (17 isolated from animals and 31 isolated from human specimens, and two standard strains) were analyzed using PCR (using two pairs of primers). Then, to determine the effects of sub-MIC of gentamicin on bacterial survival and growth, colony forming unit was quantitated and turbidity was assessed following the treatment of Brucella spp, with ½ MIC of gentamicin at different time intervals. Furthermore, the colony forming unit of Brucella spp, was assessed under acid stress (pH = 5.5) compared to the control (pH = 7.6). Moreover, the expression of TA system genes in Brucella spp, was evaluated 1 h after treatment using qRT-PCR method.
RESULTS
A total of 50 isolates, including 41 (82%) Brucella melitensis and 7 (14%) Brucella abortus with two standard strains Brucella melitensis (16 M) and Brucella abortus (B19) were investigated. Our results revealed the reduced growth of Brucella spp. in the presence of sub-MIC of gentamicin compared to the control. Furthermore, according to the results of qRT-PCR assay, gentamicin could increase the expression of TA system genes. Also, results of qRT-PCR showed that under acid stress, the expression of TA system gene COGT/COGAT decreased compared to the control.
CONCLUSION
Although the exact role of the TA systems in response to stress is still unclear, our study provided information on the effect of the type II TA systems under the acid and antibiotic stress conditions. However, further studies are still required.
背景
布鲁氏菌病是一种常见的人畜共患病。细菌通过不同的机制来应对应激条件，其中之一是毒素-抗毒素（TA）系统。人们认为，TA 系统在疾病的慢性化过程中起着关键作用。本研究探讨了布鲁氏菌属在酸和抗生素应激下 TA 系统基因的表达。
方法
使用 PCR（使用两对引物）分析了 50 株布鲁氏菌分离株（17 株来自动物，31 株来自人类标本，还有 2 株标准株）。然后，为了确定小剂量庆大霉素对细菌存活和生长的影响，在不同时间间隔用 1/2 MIC 的庆大霉素处理布鲁氏菌属后，通过平板计数法和浊度法来定量细菌集落形成单位。此外，与对照（pH = 7.6）相比，还评估了布鲁氏菌属在酸性应激（pH = 5.5）下的集落形成单位。此外，用 qRT-PCR 法在处理后 1 小时评估 TA 系统基因在布鲁氏菌属中的表达。
结果
共检测了 50 株分离株，包括 41 株（82%）布鲁氏菌 melitensis 和 7 株（14%）布鲁氏菌 abortus ，还有 2 株标准株布鲁氏菌 melitensis（16M）和布鲁氏菌 abortus（B19）。我们的结果显示，与对照相比，小剂量庆大霉素存在时布鲁氏菌属的生长减少。此外，根据 qRT-PCR 试验的结果，庆大霉素可以增加 TA 系统基因的表达。此外，qRT-PCR 结果表明，在酸性应激下，TA 系统基因 COGT/COGAT 的表达与对照相比降低。
结论
尽管 TA 系统在应对应激方面的确切作用仍不清楚，但我们的研究提供了有关在酸和抗生素应激条件下 II 型 TA 系统的作用的信息。然而，仍需要进一步的研究。
Zotero 插件