Novel molecular mechanism of high ribonucleic acid yield in Saccharomyces pastorianus revealed by transcriptomics

Abstract

Ribonucleic acid (RNA) and its degradation products find widespread application across various industries, including the food condiments sector. This study employed comparative transcriptomics to investigate the genetic mechanisms underlying RNA synthesis in the mutant Saccharomyces pastorianus strain G03H8, which exhibited a high RNA yield. To identify genetically engineered targets, single gene over-expression and CRISPR/Cas9 gene editing technology were utilized. The differential enrichment results revealed a close association between RNA metabolism and cellular processes such as the cell cycle, purine metabolism, nucleotide metabolism, and other metabolic pathways. Subsequently, we selected the top nine most promising genes to evaluate their impact on RNA synthesis. In these nine targets, upon comparing the RNA yield of the genetically engineered strains, G03-TAL1, G03-PGM2, G03-ΔPRS5, and G03-△DBP8, with the parent strain G03, significant improvements of 31.7%, 41.8%, 72.1%, and 46.7% were observed, respectively. Furthermore, these four genes were found to enhance the strain's growth and augment the pentose phosphate pathway, thus demonstrating the considerable potential for enhancing RNA yield. Notably, this study represents the first instance of identifying the upregulation of TAL1, PGM2, PRS5, and DBP8 as a means to increase RNA content in S. pastorianus. Consequently, our findings present novel genetic targets for enhancing RNA production and contribute to a deeper understanding of the mechanisms involved in high RNA synthesis in S. pastorianus.