The sequence of the flocculation gene (FLO1G) was determined. The result of sequcencing showed that:the cloned gene contains a large open reading frame (ORF) of 3936 bp and encodes for a protein of 1312 amino acid. Ac...The sequence of the flocculation gene (FLO1G) was determined. The result of sequcencing showed that:the cloned gene contains a large open reading frame (ORF) of 3936 bp and encodes for a protein of 1312 amino acid. According to the result of homologous analysis, the cloned gene is homologous to FLO1 but with 675 bp deletion in the ORF region. The missing part belongs to one of the four repeated sequence family of FLO1. Since the cloned DNA fragment can trigger strong flocculence to non-flocculent strain S.cerevisiae YS58, we concluded that the missing part is not the crutical part for the flocculent ability of the gene.展开更多
Saccharomyces cerevisiae osmotic fragile mutants were obtained from parental strain SH208 15 by N methyl N’ nitro N nitrosoguanidine(NTG) treatments. Three mutants, HF2, HF7 and HF9 showed high degree of release of t...Saccharomyces cerevisiae osmotic fragile mutants were obtained from parental strain SH208 15 by N methyl N’ nitro N nitrosoguanidine(NTG) treatments. Three mutants, HF2, HF7 and HF9 showed high degree of release of the intracellular components into medium under hypo osmotic condition and were studied in details. They showed some similar phenotypes to the previously reported fragile mutants, including hypo osmolarity sensitivity, temperature sensitivity and sensitivity to zymolyase indicating the existence of cell wall integrity defect. However, the three mutants differ from the reported mutants in some respects. Firstly, The temperature sensitivity of the isolated three mutants could not be complemented by osmotic stabilizer, while that of the PKC1 pathway mutants could be restored. Secondly, the degree of glycosylation of invertase in HF2, HF7 and HF9 did not decrease as that of srb1/vig9 mutants when compared with invertase in wild type strain respectively. In addition, the three mutants differ from each other. Hence, the three mutants are putative novel fragile mutants defect in cell wall. They can be used to further study the metabolism of yeast cell wall in biochemical and genetic levels and have the potential value to release intracellular heterologous proteins in high yield.展开更多
文摘The sequence of the flocculation gene (FLO1G) was determined. The result of sequcencing showed that:the cloned gene contains a large open reading frame (ORF) of 3936 bp and encodes for a protein of 1312 amino acid. According to the result of homologous analysis, the cloned gene is homologous to FLO1 but with 675 bp deletion in the ORF region. The missing part belongs to one of the four repeated sequence family of FLO1. Since the cloned DNA fragment can trigger strong flocculence to non-flocculent strain S.cerevisiae YS58, we concluded that the missing part is not the crutical part for the flocculent ability of the gene.
文摘Saccharomyces cerevisiae osmotic fragile mutants were obtained from parental strain SH208 15 by N methyl N’ nitro N nitrosoguanidine(NTG) treatments. Three mutants, HF2, HF7 and HF9 showed high degree of release of the intracellular components into medium under hypo osmotic condition and were studied in details. They showed some similar phenotypes to the previously reported fragile mutants, including hypo osmolarity sensitivity, temperature sensitivity and sensitivity to zymolyase indicating the existence of cell wall integrity defect. However, the three mutants differ from the reported mutants in some respects. Firstly, The temperature sensitivity of the isolated three mutants could not be complemented by osmotic stabilizer, while that of the PKC1 pathway mutants could be restored. Secondly, the degree of glycosylation of invertase in HF2, HF7 and HF9 did not decrease as that of srb1/vig9 mutants when compared with invertase in wild type strain respectively. In addition, the three mutants differ from each other. Hence, the three mutants are putative novel fragile mutants defect in cell wall. They can be used to further study the metabolism of yeast cell wall in biochemical and genetic levels and have the potential value to release intracellular heterologous proteins in high yield.
