Genetic Modulation of ATF1 in Saccharomyces cerevisiae for Enhanced Acetate Ester Production and Flavor Profile in a Sour Meat Model System

TL;DR

This study shows how modifying the ATF1 gene in yeast can boost the production of fruity esters, improving the flavor of fermented meats.

Contribution

The study reveals ATF1's role in a broader metabolic network for flavor enhancement in solid-state fermented meats.

Findings

ATF1 overexpression increased ethyl acetate by 70.15% and produced significant isoamyl acetate.

ATF1 deletion reduced ethyl acetate by 61.23%.

Transcriptomic analysis showed ATF1 influenced central carbon metabolism and precursor pathways.

Abstract

Acetate esters, synthesized by alcohol acyltransferase (AATases) encoded primarily by the ATF1 gene, are pivotal for the desirable fruity aroma in fermented foods. However, the role and regulatory impact of ATF1 in solid-state fermented meat remain largely unexplored. This study engineered Saccharomyces cerevisiae by knocking out and overexpressing ATF1 to investigate its influence on flavor formation in a sour meat model system. Compared to the wild-type strain, ATF1 overexpression (SCpA group) increased ethyl acetate content by 70.15% and uniquely produced significant levels of isoamyl acetate. Conversely, ATF1 deletion (SCdA group) led to a 61.23% reduction in ethyl acetate. Transcriptomic analysis revealed that ATF1 overexpression triggered a systemic metabolic shift, not only activating the final esterification step but also upregulating key genes in central carbon metabolism (SUC2, ICL1), amino acid biosynthesis, and precursor supply pathways (ACS2, ADH1). This synergistic regulation redirected metabolic flux towards the accumulation of both alcohol and acyl-CoA precursors, thereby amplifying acetate ester synthesis. Our findings demonstrate that ATF1 is a critical engineering target for flavor enhancement in fermented meats and uncover a broader metabolic network it influences, providing a robust strategy for the targeted modulation of food flavor profiles.

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