title: Characterization of a tryptophan 6-halogenase from Streptomyces toxytricini.
abstract: Tryptophan (Trp) halogenases are found in various bacteria and play an important role in natural product biosynthesis. Analysis of the genome of Streptomyces toxytricini NRRL 15443 revealed an ORF, stth, encoding a putative Trp halogenase within a non-ribosomal peptide synthetase gene cluster. This gene was cloned into pET28a and functionally overexpressed in Escherichia coli. The enzyme halogenated both L - and D -Trp to yield the corresponding 6-chlorinated derivatives. The optimum activity was at 40°C and pH 6 giving k (cat) /K (M) value of STTH of 72,000 min(-1) M(-1). The enzyme also used bromide to yield 6-bromo-Trp.
authors.affiliation: Department of Biological Engineering, Utah State University, 4105 Old Main Hill, Logan, UT 84322-4105, USA.
authors.forename: Jia
authors.initials: J
authors.lastname: Zeng
authors.forename: Jixun
authors.initials: J
authors.lastname: Zhan
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D006639:Histidine / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D005810:Multigene Family; D009842:Oligopeptides / Q000737:chemistry; D010088:Oxidoreductases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010802:Phylogeny; D011993:Recombinant Fusion Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D013302:Streptomyces / Q000201:enzymology* / Q000235:genetics; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; C471213:His-His-His-His-His-His; D009842:Oligopeptides; D011993:Recombinant Fusion Proteins; D006639:Histidine; D010088:Oxidoreductases; C407363:tryptophan halogenase