Breeding of Saccharomyces cerevisiae with a High-Throughput Screening Strategy for Improvement of S-Adenosyl-L-Methionine Production

• Published in: Applied biochemistry and biotechnology 2024-03, Vol.196 (3), p.1450-1463
• Main Authors: Hu, Zhong-Ce, Tao, Yun-Chao, Pan, Jun-Chao, Zheng, Chui-Mu, Wang, Yuan-Shan, Xue, Ya-Ping, Liu, Zhi-Qiang, Zheng, Yu-Guo
• Format: Article
• Language: English
• Subjects: Biochemistry; Biosynthesis; Biotechnology; Breeding; Chemistry; Chemistry and Materials Science; Colonies; Ergosterol; Fermentation; Fungi; Genes; High-throughput screening; High-Throughput Screening Assays; Industrial production; Methionine; Mutagenesis; Mutants; Nystatin; Original Article; Plant Breeding; Racemethionine; S-Adenosylmethionine; Saccharomyces cerevisiae; Saccharomyces cerevisiae - genetics; Screening; Yeast
• ISSN: 0273-2289; 1559-0291
• DOI: 10.1007/s12010-023-04622-7

S-adenosyl-l-methionine (SAM), a vital physiologically active substance in living organisms, is produced by fermentation over Saccharomyces cerevisiae . The main limitation in SAM production was the low biosynthesis ability of SAM in S. cerevisiae . The aim of this work is to breed an SAM-overproducing mutant through UV mutagenesis coupled with high-throughput selection. Firstly, a high-throughput screening method by rapid identification of positive colonies was conducted. White colonies on YND medium were selected as positive strains. Then, nystatin/sinefungin was chosen as a resistant agent in directed mutagenesis. After several cycles of mutagenesis, a stable mutant 616–19-5 was successfully obtained and exhibited higher SAM production (0.41 g/L vs 1.39 g/L). Furthermore, the transcript levels of the genes SAM2 , ADO1 , and CHO2 involved in SAM biosynthesis increased, while ergosterol biosynthesis genes in mutant 616–19-5 significantly decreased. Finally, building on the above work, S. cerevisiae 616–19-5 could produce 10.92 ± 0.2 g/L SAM in a 5-L fermenter after 96 h of fermentation, showing a 2.02-fold increase in the product yield compared with the parent strain. Paving the way of breeding SAM-overproducing strain has improved the good basis for SAM industrial production.