Natural selection shapes the evolution of the metabolome in Saccharomyces cerevisiae.

Natural selection significantly influences metabolite abundance in Saccharomyces cerevisiae, with about 28.58% of metabolites under directional selection, shaping the metabolome's evolution.

• Why it matters: Understanding how natural selection acts on metabolites fills a critical gap in linking genotype to phenotype, as metabolite levels directly reflect cellular function and evolutionary adaptation.
• What they did: The study quantified 1,037 metabolites across mutation accumulation lines, wild isolates, and ancestors using LC-MS/MS, comparing variance and directional bias to infer selection pressures.
• The result: Findings show strong conservation of metabolite levels among wild strains and reveal that natural selection tends to increase high-abundance metabolites while decreasing low-abundance ones, especially amino acids, advancing knowledge of molecular evolution.