ANALYSIS OF THE CO DEHYDROGENASE ACETYL-COENZYME-A SYNTHASE OPERON OFMETHANOSARCINA-THERMOPHILA/

Citation
Ja. Maupinfurlow et Jg. Ferry, ANALYSIS OF THE CO DEHYDROGENASE ACETYL-COENZYME-A SYNTHASE OPERON OFMETHANOSARCINA-THERMOPHILA/, Journal of bacteriology, 178(23), 1996, pp. 6849-6856
Citations number
39
Categorie Soggetti
Microbiology
Journal title
ISSN journal
00219193
Volume
178
Issue
23
Year of publication
1996
Pages
6849 - 6856
Database
ISI
SICI code
0021-9193(1996)178:23<6849:AOTCDA>2.0.ZU;2-1
Abstract
The cdhABC genes encoding the respective alpha, epsilon, and beta subu nits of the five-subunit (alpha, beta, gamma, delta, and epsilon) CO d ehydrogenase/acetyl-coenzyme synthase (CODH/ACS) complex from Methanos arcina thermophila were cloned and sequenced. Northern (RNA) blot anal yses indicated that the cdh genes encoding the five subunits and an op en reading frame (ORF1) with unknown function are cotranscribed during growth on acetate. Northern blot and primer extension analyses sugges ted that mRNA processing and multiple promoters may be involved in edi t transcript synthesis. The putative CdhA (alpha subunit) and CdhB (ep silon subunit) proteins each have 40% identity to CdhA and CdhB of the CODH/ACS complex from Methanosaeta soehngenii. The cdhC gene encodes the beta subunit (CdhC) of the CODH/ACS complex from M. thermophila. T he N-terminal 397 amino acids of CdhC are 42% identical to the C-termi nal half of the or subunit of CODH/ACS from the acetogenic anaerobe Cl ostridium thermoaceticum, Sequence analysis suggested potential struct ures and functions for the previously uncharacterized beta subunit fro m M. thermophila. The deduced protein sequence of ORF1, located betwee n the cdhC and cdhD genes, has 29% identity to NifH2 from Methanobacte rium ivanovii.