Cloning of the sdsA gene encoding solanesyl diphosphate synthase from Rhodobacter capsulatus and its functional expression in Escherichia coli and Saccharomyces cerevisiae.
Different organisms produce different species of isoprenoid quinones, each with its own distinctive length. These differences in length are commonly exploited in microbial classification. The side chain length of quinone is determined by the nature of the polyprenyl diphosphate synthase that catalyzes the reaction. To determine if the side chain length of ubiquinone (UQ) has any distinct role to play in the metabolism of the cells in which it is found, we cloned the solanesyl diphosphate synthase gene (sdsA) from Rhodobacter capsulatus SB1003 and expressed it in Escherichia coli and Saccharomyces cerevisiae. Sequence analysis revealed that the sdsA gene encodes a 325-amino-acid protein which has similarity (27 to 40%) with other prenyl diphosphate synthases. Expression of the sdsA gene complemented a defect in the octaprenyl diphosphate synthase gene of E. coli and the nonrespiratory phenotype resulting from a defect in the hexaprenyl diphosphate synthase gene of S. cerevisiae. Both E. coli and S. cerevisiae expressing the sdsA gene mainly produced solanesyl diphosphate, which resulted in the synthesis of UQ-9 without any noticeable effect on the growth of the cells. Thus, it appears that UQ-9 can replace the function of UQ-8 in E. coli and UQ-6 in S. cerevisiae. Taken together with previous results, the results described here imply that the side chain length of UQ is not a critical factor for the survival of microorganisms.
Okada
K
K
Department of Applied Bioscience and Biotechnology, Faculty of Life and Environmental Science, Shimane University, Matsue, Japan.
Kamiya
Y
Y
Zhu
X
X
Suzuki
K
K
Tanaka
K
K
Nakagawa
T
T
Matsuda
H
H
Kawamukai
M
M
D019883:Alkyl and Aryl Transferases; D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D004122:Dimethylallyltranstransferase / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D011106:Polyisoprenyl Phosphates / Q000096:biosynthesis; D016133:Polymerase Chain Reaction; D016354:Rhodobacter capsulatus / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D014166:Transferases / Q000235:genetics* / Q000378:metabolism*; D014451:Ubiquinone / Q000096:biosynthesis*
D011106:Polyisoprenyl Phosphates; D014451:Ubiquinone; C063778:solanesyl pyrophosphate; D014166:Transferases; D019883:Alkyl and Aryl Transferases; C048987:octaprenyl pyrophosphate synthetase; D004122:Dimethylallyltranstransferase; C036826:trans-pentaprenyltranstransferase; C022644:trans-octaprenyltranstransferase; C030571:ubiquinone 9