title: Characterization of beta-carotene ketolases, CrtW, from marine bacteria by complementation analysis in Escherichia coli.
abstract: A complementation analysis was performed in Escherichia coli to evaluate the efficiency of beta-carotene ketolases (CrtW) from the marine bacteria Brevundimonas sp. SD212, Paracoccus sp. PC1 (Alcaligenes PC-1), and Paracoccus sp. N81106 (Agrobacterium aurantiacum), for astaxanthin production. Each crtW gene was expressed in Escherichia coli synthesizing zeaxanthin due to the presence of plasmid pACCAR25DeltacrtX. Carotenoids that accumulated in the resulting E. coli transformants were examined by chromatographic and spectroscopic analyses. The transformant carrying the Paracoccus sp. PC1 or N81106 crtW gene accumulated high levels of adonixanthin, which is the final astaxanthin precursor for CrtW, and astaxanthin, while the E. coli transformant with crtW from Brevundimonas sp. SD212 did not accumulate any adonixanthin and produced a high level of astaxanthin. These results show efficient conversion by CrtW of Brevundimonas sp. SD212 from adonixanthin to astaxanthin, which is a new-found characteristic of a bacterial CrtW enzyme. The phylogenetic positions between CrtW of the two genera, Brevundimonas and Paracoccus, are distant, although they fall into alpha-Proteobacteria.
authors: Laboratory of Applied Molecular Design, Marine Biotechnology Institute, Heita, Kamaishi-shi, Iwate 026-0001, Japan.
authors: Seon-kang
authors: SK
authors: Choi
authors: Yasuhiro
authors: Y
authors: Nishida
authors: Satoru
authors: S
authors: Matsuda
authors: Kyoko
authors: K
authors: Adachi
authors: Hiroaki
authors: H
authors: Kasai
authors: Xue
authors: X
authors: Peng
authors: Sadao
authors: S
authors: Komemushi
authors: Wataru
authors: W
authors: Miki
authors: Norihiko
authors: N
authors: Misawa
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000145:classification / Q000235:genetics*; D002338:Carotenoids / Q000032:analysis / Q000378:metabolism*; D042063:Caulobacteraceae / Q000145:classification / Q000201:enzymology / Q000235:genetics*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D017931:DNA Primers / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005816:Genetic Complementation Test; D005822:Genetic Vectors; D010105:Oxygenases / Q000096:biosynthesis* / Q000145:classification / Q000235:genetics*; D010230:Paracoccus / Q000145:classification / Q000201:enzymology / Q000235:genetics*; D010802:Phylogeny; D020539:Sequence Analysis, Protein; D024341:Xanthophylls / Q000032:analysis / Q000096:biosynthesis
chemical_list: D001426:Bacterial Proteins; D017931:DNA Primers; D024341:Xanthophylls; D002338:Carotenoids; C005948:astaxanthine; D010105:Oxygenases; C093259:beta-carotene ketolase