title: cDNA cloning and characterization of vanadium-dependent bromoperoxidases from the red alga Laurencia nipponica.
abstract: The marine red alga genus Laurencia is one of the richest producers of unique brominated compounds in the marine environment. The cDNAs for two Laurencia nipponica vanadium-dependent bromoperoxidases (LnVBPO1 and LnVBPO2) were cloned and expressed in Escherichia coli. Enzyme assays of recombinant LnVBPO1 and LnVBPO2 using monochlorodimedone revealed that they were thermolabile but their Km values for Br(-) were significantly lower than other red algal VBPOs. The bromination reaction was also assessed using laurediol, the predicted natural precursor of the brominated ether laurencin. Laurediol, protected by trimethylsilyl at the enyne, was converted to deacetyllaurencin by the LnVBPOs, which was confirmed by tandem mass spectrometry. Native LnVBPO partially purified from algal bodies was active, suggesting that LnVBPO is functional in vivo. These results contributed to our knowledge of the biosynthesis of Laurencia brominated metabolites.
authors.affiliation: a Graduate School of Environmental Science , Hokkaido University , Sapporo , Japan.
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kaneko
authors.forename: Kenji
authors.initials: K
authors.lastname: Washio
authors.forename: Taiki
authors.initials: T
authors.lastname: Umezawa
authors.forename: Fuyuhiko
authors.initials: F
authors.lastname: Matsuda
authors.forename: Masaaki
authors.initials: M
authors.lastname: Morikawa
authors.forename: Tatsufumi
authors.initials: T
authors.lastname: Okino
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics*; D054879:Halogenation; D044722:Laurencia / Q000201:enzymology* / Q000235:genetics*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010544:Peroxidases / Q000737:chemistry / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D011487:Protein Conformation; D014639:Vanadium / Q000378:metabolism*
chemical_list: D018076:DNA, Complementary; D014639:Vanadium; D010544:Peroxidases; C026195:bromide peroxidase
keywords: Laurencia; acetogenins; biosynthesis; laurencin; vanadium-dependent bromoperoxidase