天蓝色链霉菌分化调控基因scrX的功能研究

克隆天蓝色链霉菌中一个新基因ｓｃｒＸ并进行了序列分析，利用基因破坏策略 进行了该基因的功能研究．结果表明，ｓｃｒＸ基因由６６０个碱基组成，编码产物是一个２２０ 个氨基酸残基的蛋白质；该基因含有３个在链霉菌中的稀有密码子──ＡＡＡ，ＡＡＡ和 ＡＴＡ，是典型的在翻译水平上受到严紧调控的分化调控基因．氨基酸序列同源性比较 结果表明，ｓｃｒＸ编码蛋白属于原核生物转录调控蛋白Ｉｃ１Ｒ家族．基因功能研究结果揭示， ｓｃｒＸ基因在天蓝色链霉菌孢子形成中可能起正调控作用．

The function of a regulatory gene, scrX related to differentiation in Streptomyces coelicolor

A new gene, scrX from Streptomyces coelicolor was cloned and sequenced. It consists of 660 base pair, encoding a peptide of 220 amino acids. There are three rare codons in scrX which are AAA, AAA and ATA. scrXgene may be a typical differentiation regulator which was strictly controlled at translational level. The comparison of amino acids also revealed that ScrX belonged to Id R family which acted in transcriptional regulation of prokaryote. Studies on gene function by gene disruption and complementation indicated that scrX may play a positive regulation role in spore formation of Streptomyces coelicolor.A new gene, scrX from Streptomyces coelicolor was cloned and sequenced. It consists of 660 base pair, encoding a peptide of 220 amino acids. There are three rare codons in scrX which are AAA, AAA and ATA. scrXgene may be a typical differentiation regulator which was strictly controlled at translational level. The comparison of amino acids also revealed that ScrX belonged to Id R family which acted in transcriptional regulation of prokaryote. Studies on gene function by gene disruption and complementation indicated that scrX may play a positive regulation role in spore formation of Streptomyces coelicolor.

玫瑰黄链霉菌Men-myco-93-63中3个调控基因的检测

玫瑰黄链霉菌(Streptomyces roseoflavus)Men-myco-93-63及其发酵液对多种重要植物病原菌均表现出很强的抑制作用,在植物病害生物防治方面有很大的应用潜力。根据天蓝色链霉菌A3(2)调控基因tcrA、sarA和scrX序列设计引物,扩增Men-myco-93-63基因组DNA,分别获得705bp、1 472bp和473bp的片段,经测序和比对,上述片段与天蓝色链霉菌A3(2)的tcrA、sarA和scrX基因在核苷酸序列和氨基酸序列上同源性均为99%,因此,推测玫瑰黄链霉菌Men-myco-93-63中很可能含有这些调控基因。Men-myco-93-63中这3个调控基因的初步检测为玫瑰黄链霉菌功能基因的获得、菌株的遗传改良和代谢调控途径的研究提供了重要依据。