桃根癌病菌拮抗放线菌抑菌活性物质的分离及其初步鉴定

Isolation and Preliminary Identification of Antimicrobial Peptides Produced by Antagonistic Actinomycetes against Peach Crown Gall(Agrobacterium tumefaciens)

[目的]分离并初步鉴定从桃树高发根癌病土壤中获得的拮抗线菌G19菌株的抑菌活性物质。[方法]采用蛋白沉淀法对拮抗放线菌G19菌株的抑菌活性物质进行粗提,利用高效液相色谱仪、中压制备色谱仪对其进行分离、纯化,应用MALDI-TOFMS法进行分子量的测定,最后通过化学显色反应进行相关官能团的验证。[结果]经分离纯化后拮抗放线菌G19的抑菌物质被抨击出7个肽段,是分子量范围为900～1 300 Da,同时推断其含有一个Cys并携带H2O,Na+;官能团显色反应验证该物质为多肽且含有糖基。[结论]研究结果为拮抗放线菌G19菌株的抑菌物质结构的最终确定奠定了基础。

[Objective] The paper was to isolate and preliminarily identify the antimicrobial active substances of antagonistic actinomycetes strain G19 obtained from the soil highly affected by peach crown gall（Agrobacterium tumefaciens）.[Method] The antimicrobial substances of antagonistic actinomycetes strain G19 were extracted using protein precipitation method,then isolated and purified using high performance liquid chromatography and middle-pressure chromatography.Its molecular weight was determined by MALDI-TOFMS method,and the related functional groups were verified through chemical color reaction.[Result] Seven peptide portions were produced from the antimicrobial substances of antagonistic actinomycetes strain G19 after isolation and purification with the molecular weights of 900-1 300 Da.It could be also inferred that it contained Cys,and carried with H2O and Na＋.Color reaction of functional groups verified that the substance was polypeptide containing glycosyl.[Conclusion] The result provided basis for the final definition of the structure of antimicrobial substances in antagonistic actinomycetes strain G19.