title: Elucidation of a carotenoid biosynthesis gene cluster encoding a novel enzyme, 2,2'-beta-hydroxylase, from Brevundimonas sp. strain SD212 and combinatorial biosynthesis of new or rare xanthophylls.
abstract: A carotenoid biosynthesis gene cluster mediating the production of 2-hydroxyastaxanthin was isolated from the marine bacterium Brevundimonas sp. strain SD212 by using a common crtI sequence as the probe DNA. A sequence analysis revealed this cluster to contain 12 open reading frames (ORFs), including the 7 known genes, crtW, crtY, crtI, crtB, crtE, idi, and crtZ. The individual ORFs were functionally analyzed by complementation studies using Escherichia coli that accumulated various carotenoid precursors due to the presence of other bacterial crt genes. In addition to functionally identifying the known crt genes, we found that one (ORF11, named crtG) coded for a novel enzyme, carotenoid 2,2'-beta-hydroxylase, which showed intriguingly partial homology with animal sterol-C5-desaturase. When this crtG gene was introduced into E. coli accumulating zeaxanthin and canthaxanthin, the resulting transformants produced their 2-hydroxylated and 2,2'-dihydroxylated products which were structurally novel or rare xanthophylls, as determined by their nuclear magnetic resonance and high-performance liquid chromatography/photodiode array detector/atmospheric pressure chemical ionization mass spectrometry spectral data. The new carotenoid produced was suggested to have a strong inhibitory effect on lipid peroxidation.
authors.affiliation: School of Agriculture, Kinki University, Nakamachi, Nara, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nishida
authors.forename: Kyoko
authors.initials: K
authors.lastname: Adachi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kasai
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Shizuri
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Shindo
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Sawabe
authors.forename: Sadao
authors.initials: S
authors.lastname: Komemushi
authors.forename: Wataru
authors.initials: W
authors.lastname: Miki
authors.forename: Norihiko
authors.initials: N
authors.lastname: Misawa
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001709:Biotechnology / Q000379:methods; D002338:Carotenoids / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D042063:Caulobacteraceae / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D006801:Humans; D051379:Mice; D006899:Mixed Function Oxygenases / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D005810:Multigene Family; D024341:Xanthophylls / Q000096:biosynthesis*
chemical_list: D001426:Bacterial Proteins; D024341:Xanthophylls; D002338:Carotenoids; D006899:Mixed Function Oxygenases; C079232:beta-carotene hydroxylase