产表面活性素和伊枯草菌素A菌株的筛选及其脂肽类产物的特性  

Screening a surfactin and iturin A producing strain and characterization of its lipopeptide products

作　　者：朱震[1] 罗毅[1] 张鹏[1] 杨兴明[1] 冉炜[1] 沈其荣[1] 

机构地区：[1]南京农业大学资源与环境科学学院江苏省固体有机废弃物资源化高技术研究重点实验室,江苏南京210095

出　　处：《微生物学通报》2011年第10期1488-1498,共11页Microbiology China

基　　金：农业部公益性行业科技专项(No.201103004);科技部863项目(No.2010AA10Z401)

摘　　要：采用血琼脂平板法,从菜园土壤中分离到8株代谢表面活性剂的菌株,比较各菌株的排油性、抑菌性,根据合成脂肽类物质表面活性素(Surfactin)和伊枯草菌素A(Iturin A)必需的sfp、ituD和lpa-14基因设计引物,结合PCR的方法筛选到一株具广谱抗菌性且含有sfp、ituD和lpa-14 3个关键基因的细菌XZ-173。经过生理生化试验测定和16S rDNA序列系统发育学分析,将其鉴定为解淀粉芽孢杆菌(Bacillus amyloliquefaciens)。通过红外光谱(FT-IR)分析该菌株代谢产物,初步鉴定为脂肽类物质,并对照高效液相色谱(HPLC)与标准品比对结果,确定含有Surfactin和Iturin A组分。该菌株产生的脂肽粗品能使纯水的表面张力降低至26.6 mN/m,临界胶束浓度(CMC)为500 mg/L,具有很好的乳化性能,对立枯丝核菌和青枯菌表现出很好的拮抗活性。因此,产脂肽细菌XZ-173是一株应用前景广阔的功能菌。After preliminarily isolated from soil of vegetable gardens by using blood-agar method, eight strains were further examined by oil-spreading test and inhibitory test. Primers were designed according to genes （sfp, ituD, lpa-14） related to surfactin and iturinA synthesis, and one bacterial strain XZ-173 with a broad spectrum of phytopathogens was screened out by PCR of the sfp, ituD, lpa-14 gene. Based on the physiological and biochemical properties and 16S rDNA sequence analysis, it was identified as Bacillus amyloliquefaciens. The FT-IR and HPLC results indicated that the biosurfactnat produced by strain XZ-173 was lipopeptides that contained surfactin and iturin A. The prepared crude lipopeptldeS reduced the surface tension of water to 26.6 mN/m with a critical micelle concentration （CMC） of 500 mg/L and showed stable emulsification capability and strong inhibition against Rhizoctonia solani and Ralstonia solanacearum. Lipopeptide-producing stain XZ-173 had potential to be used in biological control of soil-borne plant diseases.

关 键 词：芽孢杆菌 脂肽 表面活性素 伊枯草菌素A 植物病原菌 

分 类 号：S476.1[农业科学—农业昆虫与害虫防治]