Site of glucose repression of heme biosynthesis

Abstract

Incubation of aerobic cultures of Saccharomyces cerevisiae with high concentrations of glucose leads to the repression of heme biosynthesis [I] and to the accumulation of prototetrahydroporphyrin IX, a pigment with an absorption maximum at 503 nm,

Hemes, Chlorophylls, and Related Compounds: Biosynthesis and Metabolic Regulation

“…Presumably the enzyme of the anaerobic organisms can utilize an alternative oxidant. Extracts of anaerobically grown yeast (150), photosynthetic bacteria (151), and denitrifying bacteria (152), can decarboxylate coproporphyrin anaerobically in the presence of ATP, L-methionine, and pyridine nucleotides. Tait has suggested that the direct removal of a hydride ion can occur via a sulfonium ion, which could be derived from S-adenosyl methionine (cited in ref.…”

“…153). Interestingly, in yeast, both aerobic and anaerobic coproporphyrinogen decarboxylase activities are apparently catalyzed by a single enzyme (150). Poulson and Polglase have purified the 75,000 molecular weight enzyme from yeast.…”

“…In the presence of oxygen, no cofactors were required, but anaerobic activity required a divalent metal, methionine, ATP, and either NAD+ or N A D P . The K , for coproporphyrinogcn I11 was 32 pM under aerobic conditions, and 26 p M anaerobically (150). c. Protoporphyrinogen 9 Oxidation.…”

Catabolite repression of protoporphyrin IX biosynthesis in Escherichia coli K‐12

“…It has also been established [3] that glucose repression of protoporphyrinogen oxidase results in the accumulation of its substrate -protoporphyrinogen IX -which can be readily detected spectrophotometrically in intact cells as prototetrahydroporphyrin IX. In addition, we have demonstrated [4,5] that the degree of catabolite repression of SM-dependent E. cofi can be modified by varying the dihydrostreptomycin concentration of the growth medium.…”

Purification and properties of mouse liver coproporphyrinogen oxidase

“…In mammalian cells, this enzyme is located in the intermembrane space of mitochondria [4, 51. Reports of partial purification of the protein from rat liver [6], tobacco leaves [7] and the yeast Saccharomyces cerevisiae [8] have been published but they do not lead to decisive conclusions concerning the molecular properties of the enzyme. More recently, purification to homogeneity of the enzyme from bovine liver [9] and yeast cells [lo] provided a much better knowledge of the protein.…”