摘要
从32株酵母菌中筛选到丙氨酸产生株产朊假丝酵母(Candida utilisY18),丙氨酸产量为1 mg/ml,发酵最适时间为72小时,最适pH值为6—7。用NTG和DES对菌株Y18进行诱变获得了一些芳香簇氨基酸变异株(FPA^r、T_(rp)^-、phe^-)和赖氨酸类似物抗性变异株(AEC^r)以及其他一些变异菌株。通过对这些变异菌株的氨基酸发酵研究,从芳香簇氨基酸、极性氨基酸和中性氨基酸三个方面,分析和探讨了酵母菌作为氨基酸生产菌的潜力及可行性。
A alanine productive strain Candida utilis Yl8 was obstained by screening from 32 different yeast strains.Under the optimal conditions of pH 6—7 and 72hr fermentation,the yield of alanine was 1 mg/ml.The C.utilisYl8 was mutagenesised by NTG and DES and some amino acid auxotroph(FPA^-、Trp^-、 Phe^-)and analogous resistant(AEC^r)mutant strains were selected.With the result of amino acid fermentation of these mutant strains,the paper discussed the possibility and potentiality of geast as productive strains of neutral、polar and aromatic amino acid.
