酿酒酵母单倍体菌株分离筛选及其产腺苷甲硫氨酸的初步研究

摘要

In order to obtain S-adenosyl-L-methionine (SAM)yielding haploid strain and improve its SAM production, spore-forming cultivation of Saccharomyces cerevisiae CGMCC 2842 was tested by using different medium after 11 days growth at 25 ℃ . Then the haploid strains were identified for mating type by PCR and the SAM yield was determined by HPLC. A yeast strain (MATa)was isolated from 7 haploid strains and its SAM yield reached 1. 10 g/ L after 48 h fermen-tation in 250 mL shaking flasks. As a result,a high SAM-producing haploid yeast was screened out,which could be used for genetic breeding and further strain improvement for SAM production on large scale.%获得产腺苷甲硫氨酸的二倍体酿酒酵母CGMCC 2842遗传育种单倍体亲本。采用不同产孢培养基考察了酿酒酵母的产孢率，并对酿酒酵母CGMCC 2842进行了生孢培养分离子囊孢子得到单倍体菌株，确定单倍体配型，测定不同单倍体菌株腺苷甲硫氨酸含量。从分离的七株单倍体菌株（6株a型和1株α型）中筛选出一株产腺苷甲硫氨酸较高的a配型的单倍体菌株，经250 mL摇瓶发酵48 h后产腺苷甲硫氨酸1．10 g／L。筛选得到了一株产腺苷甲硫氨酸较高a型的单倍体菌株，为菌株的进一步遗传育种改良和腺苷甲硫氨酸微生物发酵法规模化生产奠定了基础。