Fig. 1: Engineering strategies for efficient heme synthesis in Saccharomyces cerevisiae KCCM 12638.
From: Enhanced heme production in industrial Saccharomyces cerevisiae through metabolic engineering
Flux in the heme biosynthetic pathway was enhanced by overexpressing genes encoding rate-limiting enzymes (HEM2, HEM3, HEM12, and HEM13), as well as enzymes involved in the final stages of the pathway (HEM14 and HEM15). Disruption of the ROX1 and HAP1 genes derepressed HEM13 expression, and inactivation of the HMX1 gene prevented heme degradation. Genes encoding key pathway enzymes: HEM1, 5-aminolevulinate synthase; HEM2, aminolevulinate dehydratase; HEM3, porphobilinogen deaminase; HEM4, uroporphyrinogen III synthase; HEM12, uroporphyrinogen decarboxylase; HEM13, coproporphyrinogen III oxidase; HEM14, protoporphyrinogen oxidase; HEM15, protoporphyrin ferrochelatase; ROX1, repressor of hypoxic functions; HAP1, heme activator protein; HMX1, heme oxygenase 1.
