摘要
当酵母细胞处于高渗压环境时,甘油被诱导合成以提高其胞内渗透压,这一过程受HOG途径的调控。GPD1基因为HOG途径的重要靶基因,高效表达使胞内3磷酸甘油脱氢酶酶活水平提高可极大地提高甘油的产量。本研究将产甘油假丝酵母(Candidaglycerologenesis)染色体DNA经Sau3AI部分酶解后的5~10kbDNA片段与经BamHI线性化及CIP处理过的酵母大肠杆菌穿梭质粒YEp51连接,以大肠杆菌DH5α为受体,构建产甘油假丝酵母的染色体基因文库。通过遗传互补法,在含50g/L氯化钠的培养基上筛选出15个转化子,对转化子0601进行了进一步鉴定,转化子0601所含质粒YEp0601带有YEp51的标记并可以消除Saccbaromycescerevisiae642菌株由于其GPD1,GPD2两基因的缺失突变而表现出的渗透压敏感性。
The response of the yeast Saccharomyces cerevisiae t o osmotic stress is to synthesis and accumulate the glycerol in order to increase the internal osmolarity and this response is controlled by the high osmolarity glycerol (HOG) response pathway, whose important target gene is GPD1 . The increase of the activity of glycerol 3 phosphate dehydrogenase by over expression of GPD1 gene can increase the glycerol yield greatly. In this study, a gene encoding cytoplasmic glycerol 3 phosphate dehydrogenase of Candida glycerolgenesis was cloned out by inserting Sau 3AI generated chromosomal DNA fragments into the Bam HI site of a yeast E. coli shuttle vector, YEp51. Fifteen transformants were isolated on a supplemented minimal medium containing 50g/L of sodium chloride from the constructed C.glycerolgenesis genomic library by using genetic complement approach. The recombinant plasmid, YEp0601, from transformant 0601, possessed the genetic markers of YEp51 and was able to restore the osmotolerance of S.cerevisiae 642( gpd1Δ,gpd2Δ ). These indicated that a gene coding for cytoplasmic glycerol 3 phosphate dehydrogenase of C.glycerolgenesis was successfully cloned out.
出处
《微生物学报》
CAS
CSCD
北大核心
1999年第4期321-326,共6页
Acta Microbiologica Sinica
基金
国家"九五"攻关项目
关键词
产甘油假丝酵母
磷酸甘油脱氢酶
基因
克隆
Candida glycerolgenesis , Glycerol 3 phosphate deh ydrogenase, Cloning