Complementation of Escherichia coli ubiF mutation by Caenorhabditis elegans CLK-1, a product of the longevity gene of the nematode worm

• Published in: FEBS letters Vol. 543; no. 1; pp. 174 - 178
• Main Authors: Adachi, Akihiko, Shinjyo, Noriko, Fujita, Daisuke, Miyoshi, Hideto, Amino, Hisako, Watanabe, Yoh-ichi, Kita, Kiyoshi
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 22-05-2003
• Subjects: Animals; Caenorhabditis elegans; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - physiology; clk-1; Coq7p; DMQ, demethoxyubiquinone; DMQ8, 2-octaprenyl-3-methyl-6-methoxy-1,4-benzoquinone; Escherichia coli; Escherichia coli - genetics; Escherichia coli - growth & development; Escherichia coli - metabolism; Escherichia coli Proteins; ESI, electrospray ionization; Genetic Complementation Test; HPLC, high-performance liquid chromatography; Hydroxylase; Longevity; Mixed Function Oxygenases - genetics; Mutation; PCR, polymerase chain reaction; SDS, sodium dodecyl sulfate; ubiF; Ubiquinone; Ubiquinone - biosynthesis; UQ, ubiquinone; clk-1; DMQ 8, 2-octaprenyl-3-methyl-6-methoxy-1,4-benzoquinone; Hydroxylase; Escherichia coli; UQ, ubiquinone; ESI, electrospray ionization; SDS, sodium dodecyl sulfate; HPLC, high-performance liquid chromatography; Caenorhabditis elegans; Ubiquinone; DMQ, demethoxyubiquinone; PCR, polymerase chain reaction; Coq7p; ubiF
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/S0014-5793(03)00419-8

Caenorhabditis elegans CLK-1 was identified from long-lived mutant worms, and is believed to be involved in ubiquinone biosynthesis. The protein belongs to the eukaryotic CLK-1/Coq7p family, which is also similar to the bacterial Coq7 family, that hydroxylates demethoxyubiquinone, resulting in the formation of hydroxyubiquinone, a precursor of ubiquinone. In
Escherichia coli, the corresponding reaction is catalyzed by UbiF, a member of a distinct class of hydroxylase. Although previous studies suggested that the eukaryotic CLK-1/Coq7 family is a hydroxylase of demethoxyubiquinone, there was no direct evidence to show the enzymatic activity of the eukaryotic CLK-1/Coq7 family. Here we show that the plasmid encoding
C. elegans CLK-1 supported aerobic respiration on a non-fermentable carbon source of
E. coli ubiF mutant strain and rescued the ability to synthesize ubiquinone, suggesting that the eukaryotic CLK-1/Coq7p family could function as bacterial UbiF.