YEAST, HAVING INCREASED CONTENT OF SULFUR-CONTAINING COMPOUND, METHOD OF SCREENING OF SUCH YEAST AND METHOD OF CULTIVATION THEREOF

摘要

1. Yeast which exhibit adenine auxotrophy and selenic acid-sensitivity and have an increased cellular content of sulfur-containing compounds. ! 2. Yeast according to claim 1, in which said adenine auxotrophy imparted modification ADE1 gene or ADE2 gene. ! 3. Yeast according to claim 1 or 2, which further have a mutation in ADE4 gene or ADE8 gene. ! 4. Yeast according to any of claims 1-3, in which said selenic acid-sensitivity imparted modification for increasing expression of the MET25 gene. ! 5. Yeast according to any of claims 1-4, wherein said sulfur-containing compound is at least one compound selected from the group consisting of cysteine, γ-glutamiltsisteina, glutathione and tsisteinilglitsina. ! 6. A method of culturing the yeast according to any one of claims 1-5, comprising culturing said yeast in excess of adenine provided for increasing the number of yeast cells, and then culturing said yeast in a subject deficient in adenine to increase cellular content of said sulfur-containing compound. ! 7. A method of screening a yeast having increased cellular content of sulfur-containing compound, comprising subjecting a yeast which demonstrate adenine auxotrophy and selenic acid sensitivity, processing to modify a gene, the distribution of the modified yeast on a culture medium in which yeast can turn red in case of adenine deficiency to form colonies of yeast and selection of yeast colony, which is redder than before the modification. ! 8. The method of claim 7, wherein said sulfur-containing compound is at least one compound