武夷菌素生物合成调控基因wysPⅢ的功能

Functional Study of Regulator Gene wysPⅢ in the Biosynthesis of Wuyiencin

为了深入研究武夷菌素生物合成调控机理,通过筛选对武夷菌素产量有影响的基因,明确基因的功能,利用分子育种技术来获得武夷菌素高产菌株。本研究通过基因敲除和过表达技术,获得了wysPⅢ基因的缺失突变株、互补菌株和过表达菌株,验证了该基因在武夷菌素生物合成过程中的功能和武夷菌素产量的关系。结果表明:wysPⅢ基因的过表达菌株生长速率加快,产孢时间提前,而缺失突变株较野生菌株生长变慢,产孢量下降,孢子颜色由正常的深灰色变为灰白色,菌丝变稀疏,但是构建好的菌株与野生型菌株相比,武夷菌素产量没有显著变化。由此可知:wysPⅢ基因调节菌株的生长和产孢特征,而不影响武夷菌素的产量,过表达菌株生长速率加快可缩短武夷菌素发酵时间,降低生产成本。

The aim of this study is to further investigate the regulation mechanism of biosynthesis of wuyiencin,clarify the function of the genes affecting the yield of wuyiencin and obtain the high-yield producing strain of wuyiencin via molecular breeding.wysPⅢ,the wuyiencin biosynthesis gene,was knocked out and over-expressed,and wysPⅢdeletion,complementary and over-expression strains of Streptomyces.ahygroscopicus var.wuyiensis were obtained.The results showed that the over-expression strain grew much faster and sporulated earlier than the wild strain.wysPⅢ-depletion mutant grew slower and produced fewer spores than wild strain,and the color of spores turned from dark-gray to light gray.The wysPⅢ-depletion and over-expression strains yielded the same amount of wuyiencin as the wild strain.These results revealed that wysPⅢgene regulated the growth and phenotype of S.wuyiensis obviously,but did not regulate wuyiencin production.The over-expression strain can reduce the cost and save the time in the industrial fermentation production.