一株藜内生放线菌的活性分析及抗生素生物合成潜力的筛查

Activity Analysis and Antibiotics Biosynthesis Potential Screening of an Endophytic Actinomycetes from Chenopodium album L.

对一株分离自药用植物藜的内生放线菌LCB-A236进行系统学鉴定。电镜扫描后观察到螺旋状的孢子丝和椭球形的孢子,通过其形态和生理生化特征初步确定为链霉菌。分子鉴定和系统发育分析结果显示,其与Streptomyces violaceorubidus LMG 20319T (AJ781374)进化地位最接近,相似度为99.71%,确定为Streptomyces sp.。通过平板法、SRB法和Lilian Sauma等人的激动率测试模型进行抗菌、抗癌及抗糖尿病活性测试,结果显示出较强的抗癌及抗糖尿病活性和中等的抗菌活性。菌株的5类抗生素合成酶基因PCR扩增筛查结果表明,该菌株含有I-型聚酮合成酶、II-型聚酮合成酶和非核糖体多肽合成酶的基因。

An endophytic actinomycetes strain LCB-A236 isolated from medicinal plant Chenopodium al-bum L. was identified systematically. The strain produced spiral sporotrichial and ellipsoidal spores according to microscopic observation. On the basis of morphological, physiological and biochemical characteristics, the strain was identified as a member of genus Streptomyces. Phy-logenetic analysis indicated that the strain exhibited the highest similarity (99.71%) to Strep-tomyces violaceorubidus LMG 20319T (AJ781374). We confirmed it as Streptomyces sp. According to the results of activity measurements by plate method, SRB bacteriostasis and Lilian Sauma et al.’s test model of activation rate, it previously described that the strain demonstrated strong anticancer, antidiabetes activities and medium antimicrobial activity. PCR screening for the genes of five kinds of antibiotic synthetase showed that the strain possessed the genes of polyketides synthetase I, polypeptide synthetase II, and non-ribosome polypeptide synthetase simultaneously.