筛选鉴定一株产生抑菌活性物质的海洋放线菌

目的：分离筛选能够产生抑菌活性物质的海洋放线茵，并进行生理生化和16SrDNA鉴定。方法：用分离培养基培养海洋放线菌，并筛选出能够产生抑菌活性物质的菌株，对所筛选菌株的形态特征、生理生化特性进行鉴定分析；采用通用引物27F、1492R扩增该菌株的16SrDNA，对测序结果进行分析；采用Neighbor—Joining（N—J）法构建系统发育进化树。结果：筛选到一株对金黄色葡萄球菌、大肠杆菌、白色念珠菌具有较强抗性的海洋放线菌F1，该菌株好氧，中度嗜盐，在高氏I号培养基上呈白色绒粉状，16SrDNA序列比对表明该菌株与田无链霉菌（Streptomyces tanashiensis）NR043369的相似度为99％。结论：筛选到的菌株F1是一株海洋来源的放线菌，与田无链霉菌NR043369的同源性较高，可能属海洋链霉菌属，对金黄色葡萄球菌等病原菌具有较强的抑菌活性。

Isolation and Identification of a Marine Actinomycete Producing An-tibacterial Substances

Objective： To isolate and screen antibacterial actinomycetes from the ocean, and make a preliminary study on its morphological, physiological and biochemical properties and 16S rDNA identification. Methods： Anti- bacterial actinomyeetes from the ocean were isolated by the use of selective medium and the morphological physio-logical and biochemical properties were identified and analyzed. 16S rDNA sequence for actinomycetes strains was amplified by prime pairs 27F and 1492R, the acquired data were used to analyze sequence, and using Neigh- bor-Joining method to construct phylogenic tree. Results： An actinomycete strain named F1 was found to have re- markable activities to Staphylococcus aureus, Escherichia coli and Candidia albicans. The strain of F1 was aerobic and moderately halophilic, white velvet powder on the Gause＇s medium. The sequence analysis of 16S rDNA showed that F1 was closely to Streptomyces tanashiensis NR043369, with the similarity of 99%. Conclusion： The marine actinomycete strain F1 has a relatively high homology compared with S.tanashiensis NR043369. The strain F1 can produce some active substances inhibiting pathogenic bacteria including S.aureus, E.coli.