TU Darmstadt / ULB / TUbiblio

The dihydrolipoamide dehydrogenase from the crenarchaeon Acidianus ambivalens.

Batista, Ana P. ; Kletzin, Arnulf ; Pereira, Manuela M. :
The dihydrolipoamide dehydrogenase from the crenarchaeon Acidianus ambivalens.
In: FEMS microbiology letters, 281 (2) pp. 147-54. ISSN 0378-1097
[Artikel], (2008)

Kurzbeschreibung (Abstract)

A dihydrolipoamide dehydrogenase (DLDH) was purified and characterized for the first time from a crenarchaeon, Acidianus ambivalens. The holoenzyme consists of two identical subunits with a molecular mass of 45.4 kDa per monomer. It contains FAD as a prosthetic group and uses NAD+ as the preferential substrate, but can also reduce NADP+. The Michaelis-Menten constants of the forward (NAD+ reduction) and reverse (NADH oxidation) reactions were KM (dihydrolipoamide)=0.70 mM, KM (NAD+)=0.71 mM, KM (lipoamide)=1.26 mM and KM (NADH)=3.15 microM. A comparative study of NADH:lipoamide oxidoreductase and NADH:K3[Fe(CN)6] oxidoreductase activities was performed, the optimal temperature and pH being different for each: 55 degrees C, pH 7 and 89 degrees C, pH 5.5, respectively. Although DLDH is generally part of the alpha-ketoacid dehydrogenase complexes in Bacteria and Eukarya, none of these complexes has yet been isolated from Sulfolobales. The metabolic role of DLDH in these organisms is discussed.

Typ des Eintrags: Artikel
Erschienen: 2008
Autor(en): Batista, Ana P. ; Kletzin, Arnulf ; Pereira, Manuela M.
Titel: The dihydrolipoamide dehydrogenase from the crenarchaeon Acidianus ambivalens.
Sprache: Englisch
Kurzbeschreibung (Abstract):

A dihydrolipoamide dehydrogenase (DLDH) was purified and characterized for the first time from a crenarchaeon, Acidianus ambivalens. The holoenzyme consists of two identical subunits with a molecular mass of 45.4 kDa per monomer. It contains FAD as a prosthetic group and uses NAD+ as the preferential substrate, but can also reduce NADP+. The Michaelis-Menten constants of the forward (NAD+ reduction) and reverse (NADH oxidation) reactions were KM (dihydrolipoamide)=0.70 mM, KM (NAD+)=0.71 mM, KM (lipoamide)=1.26 mM and KM (NADH)=3.15 microM. A comparative study of NADH:lipoamide oxidoreductase and NADH:K3[Fe(CN)6] oxidoreductase activities was performed, the optimal temperature and pH being different for each: 55 degrees C, pH 7 and 89 degrees C, pH 5.5, respectively. Although DLDH is generally part of the alpha-ketoacid dehydrogenase complexes in Bacteria and Eukarya, none of these complexes has yet been isolated from Sulfolobales. The metabolic role of DLDH in these organisms is discussed.

Titel der Zeitschrift, Zeitung oder Schriftenreihe: FEMS microbiology letters
Band: 281
(Heft-)Nummer: 2
Fachbereich(e)/-gebiet(e): Fachbereich Biologie, Biology > Schwefelbiochemie und mikrobielle Bioenergetik, Sulfur Biochemistry and Microbial Bioenergetics
?? fb10_mikrobiologie ??
Fachbereich Biologie, Biology
Hinterlegungsdatum: 01 Sep 2009 10:28
Export:

Optionen (nur für Redakteure)

Eintrag anzeigen Eintrag anzeigen