TU Darmstadt / ULB / TUbiblio

Properties of the menaquinol oxidase (Qox) and of qox deletion mutants of Bacillus subtilis.

Lemma, E. ; Simon, J. ; Schägger, H. ; Kröger, A. (1995)
Properties of the menaquinol oxidase (Qox) and of qox deletion mutants of Bacillus subtilis.
In: Archives of microbiology, 163 (6)
Artikel, Bibliographie

Kurzbeschreibung (Abstract)

Menaquinol oxidase isolated from the membrane of Bacillus subtilis W23 was found to consist of four polypeptides (QoxA, B, C, and D) that were predicted by the sequence of the qox operon of B. subtilis 168 (Santana et al. 1992). The preparation contained 7 mol cytochrome aa3 per g protein, which corresponds to 2 mol heme A per mol enzyme of 144 kDa molecular mass. Respiration with dimethylnaphthoquinol catalyzed by the enzyme was ten times faster than that with menadiol. Activities with more electropositive quinols were negligible. The activity of the enzyme was inhibited by equimolar amounts of HQNO, while antimycin, myxothiazol, and stigmatellin were more than tenfold less effective. When cells of both strains of B. subtilis (W23 and 168) were grown with glucose, quinol respiration was an order of magnitude more active than respiration with N,N,N',N'-tetramethyl-1,4-phenylenediamine plus ascorbate. Surprisingly, the same result was obtained with mutant strains lacking qoxB. As cytochromes a and d were virtually absent, a second quinol oxidase, possibly of the cytochrome o-type, was apparently formed by the mutants.

Typ des Eintrags: Artikel
Erschienen: 1995
Autor(en): Lemma, E. ; Simon, J. ; Schägger, H. ; Kröger, A.
Art des Eintrags: Bibliographie
Titel: Properties of the menaquinol oxidase (Qox) and of qox deletion mutants of Bacillus subtilis.
Sprache: Englisch
Publikationsjahr: 1995
Titel der Zeitschrift, Zeitung oder Schriftenreihe: Archives of microbiology
Jahrgang/Volume einer Zeitschrift: 163
(Heft-)Nummer: 6
Kurzbeschreibung (Abstract):

Menaquinol oxidase isolated from the membrane of Bacillus subtilis W23 was found to consist of four polypeptides (QoxA, B, C, and D) that were predicted by the sequence of the qox operon of B. subtilis 168 (Santana et al. 1992). The preparation contained 7 mol cytochrome aa3 per g protein, which corresponds to 2 mol heme A per mol enzyme of 144 kDa molecular mass. Respiration with dimethylnaphthoquinol catalyzed by the enzyme was ten times faster than that with menadiol. Activities with more electropositive quinols were negligible. The activity of the enzyme was inhibited by equimolar amounts of HQNO, while antimycin, myxothiazol, and stigmatellin were more than tenfold less effective. When cells of both strains of B. subtilis (W23 and 168) were grown with glucose, quinol respiration was an order of magnitude more active than respiration with N,N,N',N'-tetramethyl-1,4-phenylenediamine plus ascorbate. Surprisingly, the same result was obtained with mutant strains lacking qoxB. As cytochromes a and d were virtually absent, a second quinol oxidase, possibly of the cytochrome o-type, was apparently formed by the mutants.

Fachbereich(e)/-gebiet(e): 10 Fachbereich Biologie > Microbial Energy Conversion and Biotechnology
?? fb10_mikrobiologie ??
10 Fachbereich Biologie
Hinterlegungsdatum: 16 Dez 2010 08:32
Letzte Änderung: 05 Mär 2013 09:42
PPN:
Export:
Suche nach Titel in: TUfind oder in Google
Frage zum Eintrag Frage zum Eintrag

Optionen (nur für Redakteure)
Redaktionelle Details anzeigen Redaktionelle Details anzeigen