一株缬草根际稀有放线菌的分离鉴定及其天然产物生物合成基因的筛查

Identification of an Rare Actinomycetes and Screening of Natural Products Biosynthesis Genes from Valerian Rhizosphere Soil

采用梯度稀释涂布平板法分离缬草根际土壤中的放线菌,从高氏一号培养基上分离得到1株放线菌BJA-103,对该菌形态特征、培养特征、生理生化特征及16SrDNA基因序列进行鉴定,并用简并PCR方法对其多种天然产物生物合成关键酶基因进行筛查。经分类鉴定,初步确定BJA-103为Amycolatopsis coloradensis的一个菌株;PCR筛查结果显示,该菌株含有非核糖体肽合酶(NRPS)、Ⅰ型聚酮合酶(PKS-Ⅰ)、Ⅱ型聚酮合酶(PKS-Ⅱ)以及糖肽类抗生素合成关键酶P450单加氧酶的基因。

Actinomycetes were isolated from valerian rhizosphere soil using dilution-plate method, one of them was identified based on morphological, cultural, physiological, biochemical characteristics and 16S rDNA gene sequence, and the key enzyme genes of natural products biosynthesis pathways were screened by degenerate PCR. The results showed that actinomycetes BJA-103 isolated from Gause Ⅰ medium was preliminarily identificated as a member of the genus Amycolatopsis coloradensis. PCR check-screening of its natural products biosynthesis genes revealed that it possessed the genes of non- ribosome polypeptide synthetase （NRPS）, polyketides synthetase Ⅰ （PKS- Ⅰ ）, polyketides syn- thetase Ⅱ （PKS- Ⅱ ） and glycopeptide P450 monooxygenase.