一种新的乙酰高丝氨酸内酯水解酶基因的克隆和表达

目的 获得新的降解革兰阴性细菌数量阈值感应信号分子乙酰高丝氨酸内酯类化合物(AHL)的水解酶基因。方法 选择性富集和培养土壤中耐热细菌,抽取细菌总DNA作为模板,特异性聚合酶链反应扩增乙酰高丝氨酸内酯水解酶基因,进行克隆和DNA序列分析及原核表达。结果 得到1个新的AHL水解酶基因,该基因与已知基因的核苷酸序列和对应的氨基酸序列同源性最高分别为87％和94％。该基因在原核表达系统中表达,得到了与预期相对分子质鲢(Mr)一致的蛋白质。结论 证实乙酰高丝氨酸内酯水解酶广泛存在于环境微生物中。为进一步研究提供条件。

Cloning and expression of a new acyl-homoserine lactone hydrolase gene

Objective To clone a new acyl-homoserine lactone(AHL)hydrolase gene which encodes the enzyme that degrades AHL, a widely used autoinducer in Gram negative bacteria quorum sensing system.Methods Heat resistant bacteria from soil were selectively enriched and cultured,and used to extract total genomic DNA.AHL hydrolase gene was amplified with specific primers by polymerase chain reaction(PCR).The PCR product was cloned and sequenced.The encoded AHL hydrolase was expressed in E.coli.Results A new AHL hydrolase gene was identified,with its nucleotide sequence and amino acid sequence 87% and 94% homologous to previously reported AHL hydrolase gene,respectively.A protein of expected molecular weight was expressed in recombinant E.coli.Conclusion Conclusion AHL hydrolase is widely present in environmental microbes.The newly cloned AHL hydrolase can be used for further studies.