Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Topological analysis of the aerobic membrane-bound formate dehydrogenase of Escherichia coli
Autore:
Benoit, S; Abaibou, H; Mandrand-Berthelot, MA;
Indirizzi:
InstUMRtl Sci Appl, Lab Genet Mol Microorgan & Interact Cellulaires, CNRS,Inst Natl Sci Appl Villeurbanne France F-69621 teract Cellulaires, CNRS,
Titolo Testata:
JOURNAL OF BACTERIOLOGY
fascicolo: 24, volume: 180, anno: 1998,
pagine: 6625 - 6634
SICI:
0021-9193(199812)180:24<6625:TAOTAM>2.0.ZU;2-Q
Fonte:
ISI
Lingua:
ENG
Soggetto:
SITE-DIRECTED MUTAGENESIS; NITRATE REDUCTASE; CYTOPLASMIC MEMBRANE; CLONING VECTORS; BETA-LACTAMASE; PROTEIN EXPORT; HYDROGENASE; SEQUENCE; TRANSLOCATION; RESIDUES;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
50
Recensione:
Indirizzi per estratti:
Indirizzo: Mandrand-Berthelot, MA InstUMRtl Sci Appl, Lab Genet Mol Microorgan & Interact Cellulaires, CNRS, Inst Natl Sci Appl Batiment 406,20 Ave Albert Einstein Villeurbanne France F-69621
Citazione:
S. Benoit et al., "Topological analysis of the aerobic membrane-bound formate dehydrogenase of Escherichia coli", J BACT, 180(24), 1998, pp. 6625-6634

Abstract

Besides formate dehydrogenase N (FDH-N), which is involved in the major anaerobic respiratory pathway in the presence of nitrate, Escherichia coli synthesizes a second isoenzyme, called FDH-O, whose physiological role is to ensure rapid adaptation during a shift from aerobiosis to anaerobiosis. FDH-O is a membrane-bound enzyme complex composed of three subunits, alpha (FdoG), beta (FdoH), and gamma (FdoI), which exhibit high sequence similarity to the equivalent polypeptides of FDH-N. The topology of these three subunits has been studied by using blaM (beta-lactamase) gene fusions. A collection of 47 different randomly generated Fdo-BlaM fusions, 4 site-specific fusions, and 3 sandwich fusions were isolated along the entire sequence of thethree subunits. In contrast to previously reported predictions from sequence analysis, our data suggested that the alpha beta catalytic dimer is located in the cytoplasm, with a C-terminal anchor for beta protruding into theperiplasm. As expected, the gamma subunit, which specifies cytochrome b, was shown to cross the cytoplasmic membrane four times, with the N and C termini exposed to the cytoplasm. Protease digestion studies of the S-35-labelled FDH-O heterotrimer in spheroplasts add further support to this model. Consistently, prior studies regarding the bioenergetic function of formate dehydrogenase provided evidence for a mechanism in which formate is oxidizedin the cytoplasm.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 24/11/20 alle ore 13:32:00