武夷菌素产生菌CK-15中转录调控因子wysR3的功能研究

Functional Study of wysR3 as a Regulator for Wuyiencin Biosynthesis in Streptomyces wuyiensis CK-15

wys R3是武夷菌素产生菌Streptomyces ahygroscopicus var.wuyiensis CK-15中可能的调控因子。为了验证wys R3是否参与武夷菌素生物合成基因的转录调节,构建了用于过表达wys R3的基因重组质粒p SETC-R,并通过接合转移的方法转化至武夷菌素产生菌S.wuyiensis CK-15中,构建过表达菌株。过表达菌株生长速度明显缓慢;通过摇瓶发酵和HPLC检测分析发现,武夷菌素产量与野生型菌株相比没有发生明显变化;DNS法测定发酵液中糖含量也没有发生明显变化,说明该基因与武夷菌素的产量和糖含量在该种条件下没有直接关系,但是影响菌株表型生长。

wysR3 is the putative regulatory gene in wuyiencin biosynthetic gene cluster from Streptomyces ahygroscopicus vat. wuyiensis CK-15. In order to test if wysR3 is involved in the regulation of transcription of wuyiencin biosynthetic genes, we constructed plasmid pSETC-R and introduced into S. wuyiensis CK-15 by conjugation, which produced the over-expression strain. The growth rate of overexpression strain is significantly slower than that of the wild-type. HPLC analysis indicated that wuyiencin production in wild-type and recombinant strains did not have any difference. The method of DNS was applied to the detection of sugar content for two strain＇s wuyiencin fermentation broth, and the results showed that the sugar content had no difference between them. These results suggested that, under the conditions used here, the DeoR-family regulator did not have any significant function in sugar metabolism or antibiotic production except morphological development.