Open AccessAnalysis of β‐ketothiolase and acetoacetyl‐CoA reductase genes of a methylotrophic bacterium, Paracoccus denitrifleans , and their expression in Escherichia coli
Author(s) -
Yabutani Tetsuya,
Maehara Akira,
Ueda Shunsaku,
Yamane Tsuneo
Publication year - 1995
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1995.tb07865.x
Subject(s) - paracoccus denitrificans , escherichia coli , bacteria , biochemistry , biology , gene , chemistry , microbiology and biotechnology , enzyme , genetics
The β‐ketothiolase gene ( phaA ) and acetoacetyl‐CoA reductase gene ( phaB ) were isolated from Paracoccus denitrificans . Nucleotide sequence analysis showed that they encoded proteins of 391 amino acids with a molecular mass of 40744 Da and of 242 amino acids with a molecular mass of 25614 Da, respectively. The predicted gene products exhibited high amino acid identities with those from other bacteria: 64.4–74.0% for the phaA gene product and 47.6–80.6% for the phaB gene product, respectively. Both genes were co‐transcribed in a recombinant Escherichia coli . In addition, promoter activity was detected upstream of the phaA gene. Hence, the two genes are organized as an operon, phaA ‐ phaB , in P. denitrificans . NADH was preferred to NADPH as a cofactor of acetoacetyl‐CoA reductase.