摘要
AcrA是革兰氏阴性菌中的一种膜融合蛋白,现今关于AcrA蛋白的研究,以AcrA蛋白在细菌中药物外排等膜转运过程中的调节作用为主。为了阐明细菌中acrA基因敲除后,该菌在溶血性、毒理性、压力胁迫性及抗生素敏感性等生理功能的变化,以嗜水气单胞菌(Aeromonas hydrophila)为研究对象,利用无痕敲除等分子生物学手段构建acrA(AHA_2911)的缺失菌株,并对野生菌株和缺失菌株的溶血性、胞外蛋白酶活、抗生素敏感性、高温胁迫、生长趋势以及生物膜形成能力等生理特性进行了测定。结果显示,敲除菌株的溶血性和胞外蛋白酶活并未受到影响,但acrA基因敲除后增加了该菌对卡那霉素、罗红霉素、巴罗沙星抗生素及吖啶黄素染料的敏感度并且显著提高了嗜水气单胞菌的生物膜形成能力。但是,ΔacrA在42℃下的生长趋势及其生物膜形成能力明显弱于野生株。以上研究证明嗜水气单胞菌acrA基因在药物外排泵中有一定的功能,并且提示该基因可能在细菌的高温耐受性及生物膜形成中起重要作用。
AcrA is a membrane fusion protein in Gram-negative bacteria,and scientists mainly study the regulation of AcrA protein in the process of drug efflux and other membrane transport in bacteria.To elucidate the effects of acrA deficient strainΔacrA in the bacteria on physiological functions such as hemolytic,toxicological,stress and antibiotic sensitivity,acrA(AHA_2911)deleted strain was constructed in A.hydrophila using traceless based homologous recombination technology.The physiological phenotypes,such as hemolytic,extracellular protease activity,antibiotics susceptibility,high temperature stress,growth trends,and biofilm formation ability for both wild strain andΔacrA were measured.The results showed that the hemolytic and extracellular protease activities in theΔacrA were not affected,while the acrA deletion increased the antibiotics sensitivity of theΔacrA to kanamycin,erythromycin,balofloxacin and acriflavinium chloride,and significantly improved the biofilm formation.But,the growth trend ofΔacrA and its biofilm formation ability at 42oC were significantly lower than wild strain.The above studies proved that acrA has a certain function in drug efflux pumps and suggested that it may play an important role in the high temperature tolerance and biofilm formation.
作者
李小艳
李泽琦
汪玉倩
于晶
林镇平
林向民
LI Xiao-yan;LI Ze-qi;WANG Yu-qian;YU Jing;LIN Zhen-ping;LIN Xiang-min(School of Life Sciences,Fujian Agriculture and Forestry University,Fuzhou 350002;Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring,Fujian Agriculture and Forestry University,Fuzhou 350002)
出处
《生物技术通报》
CAS
CSCD
北大核心
2020年第11期63-69,共7页
Biotechnology Bulletin
基金
国家自然科学基金面上项目(31670129)。
关键词
acrA
嗜水气单胞菌
同源重组
生理表型
生物被膜
高温
acrA
Aeromonas hydrophila
homologous recombination
physiological phenotype
biofilm
high temperature
