title: Expression and characterization of the terminal heme synthetic enzymes from the hyperthermophile Aquifex aeolicus.
abstract: The terminal two heme biosynthetic pathway enzymes, protoporphyrinogen oxidase and ferrochelatase, of the hyperthermophilic bacterium Aquifex aeolicus have been expressed in Escherichia coli, purified to homogeneity, and biochemically characterized. Ferrochelatase and protoporphyrinogen oxidase of this organism are both monomeric, as was found for the corresponding enzymes of Bacillus subtilis. However, unlike the B. subtilis proteins, both A. aeolicus enzymes are membrane-associated. Both proteins have temperature optima over 60 degrees C. This is the first demonstration of functional heme biosynthetic enzymes in an extreme thermophilic bacterium.
authors.affiliation: Department of Microbiology, University of Georgia, Athens, GA 30602-7229, USA.
authors.forename: K F
authors.initials: KF
authors.lastname: Wang
authors.forename: T A
authors.initials: TA
authors.lastname: Dailey
authors.forename: H A
authors.initials: HA
authors.lastname: Dailey
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001419:Bacteria / Q000201:enzymology* / Q000235:genetics; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D019143:Evolution, Molecular; D005294:Ferrochelatase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D006418:Heme / Q000096:biosynthesis*; D006801:Humans; D008969:Molecular Sequence Data; D010088:Oxidoreductases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D044925:Oxidoreductases Acting on CH-CH Group Donors; D010802:Phylogeny; D050768:Protoporphyrinogen Oxidase; D017386:Sequence Homology, Amino Acid; D013696:Temperature
chemical_list: D006418:Heme; D010088:Oxidoreductases; D044925:Oxidoreductases Acting on CH-CH Group Donors; D050768:Protoporphyrinogen Oxidase; D005294:Ferrochelatase