title: Homogentisic acid is the product of MelA, which mediates melanogenesis in the marine bacterium Shewanella colwelliana D.
abstract: Shewanella colwelliana D is a marine procaryote which produces a diffusible brown pigment that correlates with melA gene expression. Previously, melA had been cloned, sequenced, and expressed in Escherichia coli; however, the reaction product of MelA had not been identified. This report identifies that product as homogentisic acid, provides evidence that the pigment is homogentisic acid-melanin (pyomelanin), and suggests that MelA is p-hydroxyphenylpyruvate hydroxylase. This is the first report of pyomelanin in an obligate marine bacterium.
authors.affiliation: Department of Microbiology, University of Maryland, College Park 20742.
authors.forename: S L
authors.initials: SL
authors.lastname: Coon
authors.forename: S
authors.initials: S
authors.lastname: Kotob
authors.forename: B B
authors.initials: BB
authors.lastname: Jarvis
authors.forename: S
authors.initials: S
authors.lastname: Wang
authors.forename: W C
authors.initials: WC
authors.lastname: Fuqua
authors.forename: R M
authors.initials: RM
authors.lastname: Weiner
mesh_terms: D015111:4-Hydroxyphenylpyruvate Dioxygenase / Q000235:genetics*; D000595:Amino Acid Sequence; D005798:Genes, Bacterial / Q000235:genetics; D006090:Gram-Negative Bacteria / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D006713:Homogentisic Acid; D008543:Melanins / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D012623:Seawater; D017386:Sequence Homology, Amino Acid; D014871:Water Microbiology
chemical_list: D008543:Melanins; C023793:pyomelanin; D015111:4-Hydroxyphenylpyruvate Dioxygenase; D006713:Homogentisic Acid