下一代底盘微生物Vibrio sp. FA2的抗生素抗性

Antibiotic resistance of next-generation microbial workhorses:a case of Vibrio sp.FA2

摘要:

【背景】细菌耐药是当前人类面临的重大挑战之一，抗生素耐药性研究是解决耐药问题的重要途径。Vibrio sp. FA2是环境中分离的一株快速生长菌，其生长速度快于目前报道的快速生长的需钠弧菌(Vibrio natriegens) 14048，并且具有多样的碳源利用能力，是具有较大潜力的下一代微生物底盘，可用于开发化合物高效生产菌株。【目的】前期对FA2菌株的常见抗生素耐药性测试发现该菌具有多重抗生素耐受性，不利于基因工程操作，并且在工业应用中会带来生态安全风险，因此有必要研究其抗生素抗性，并敲除其耐药性基因。【方法】采用抗生素药敏试验测试菌株耐药性，并且利用基因组注释分析筛选目标基因，通过基因敲除构建了关于目标基因的敲除突变株，并比较了FA2野生株和敲除株的抗生素敏感性和生长情况。【结果】系统分析了FA2菌株对以氨苄西林为代表的β-内酰胺类及氨基糖苷类等多种抗生素的耐受性，分析筛选出一系列与FA2菌株耐药性相关的基因。其中，FA2菌株对几种β-内酰胺类抗生素都有较强的耐受性，并且注释到carB6、ampC2和ampC1这3个可能的氨苄西林耐受性基因。研究了氨苄西林耐受性，对3个基因进行了敲除，敲除突变株的β-内酰胺类抗生素抗性变化表明菌株对氨苄西林的敏感性提高。【结论】阐明了FA2菌株的抗生素抗性情况，成功消除了其氨苄西林的耐药性，为实现FA2菌株的底盘开发与改造奠定了基础。

Abstract:

[Background] Antibiotic resistance in bacteria is one of the current challenges,and the study of antibiotic resistance is therefore a critical way to address this challenge.Vibrio sp.FA2,a new strain isolated from the environment,has fast growth,and its growth rate is even faster than that of the reported fast-growing strain Vibrio natriegens 14048.Vibrio sp.FA2 can use a variety of carbon sources,showing great potential to serve as the next-generation biotechnological workhorse and can be used to develop efficient strains for compound production.[Objective] We have found that FA2 has multiple antibiotic resistance,which is not conducive to genetic engineering operation and will bring ecological risks in industrial application.Therefore,it is essential to study the antibiotic resistance and knock out the resistance genes from this strain.[Methods]We profiled the antibiotic resistance of FA2 by susceptibility experiments with multiple antibiotics such as β-lactams (represented by ampicillin) and aminoglycosides,and then mined the genes related to the resistance by genome annotation.The mutants were constructed through knockout of the target genes related to ampicillin resistance.Finally,the resistance to ampicillin and the growth were compared between the knockout mutants and FA2.[Results] FA2 had strong resistance to several β-lactam antibiotics and carried three possible ampicillin resistance genes:carB6,ampC2,and ampC1.The resistance changes of the mutants indicated that the genes knockout increased the strain susceptibility to ampicillin.[Conclusion] This study clarifies the antibiotic resistance of FA2 and eliminates the resistance of FA2 to ampicillin,laying a foundation for the development and transformation of FA2 as a microbial workhorse.