title: Membrane-associated NADH dehydrogenase activities in Rhodobacter capsulatus: purification of a dihydrolipoyl dehydrogenase.
abstract: The presence of several NADH dehydrogenase activities associated with cytoplasmic membrane vesicles of chemoheterotrophically grown Rhodobacter capsulatus MT1131 was demonstrated by combining isoelectric focusing with NADH-tetranitrobluetetrazolium activity staining, a procedure that should have general applicability in the analysis of bacterial NADH dehydrogenase activities. Low pI (pI = 5.7), Mid pI (pI = 6.9) and High pI (pI = 8.5) bands were resolved. The Mid pI NADH dehydrogenase activity was purified and identified as a dihydrolipoyl dehydrogenase. Our data indicate that this dihydrolipoyl dehydrogenase is derived from a 2-oxoacid dehydrogenase complex which is associated with the cytoplasmic membrane.
authors.affiliation: Department of Biochemistry, University of Oxford, UK.
authors.forename: B C
authors.initials: BC
authors.lastname: Berks
authors.forename: A G
authors.initials: AG
authors.lastname: McEwan
authors.forename: S J
authors.initials: SJ
authors.lastname: Ferguson
mesh_terms: D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000201:enzymology; D008058:Dihydrolipoamide Dehydrogenase / Q000302:isolation & purification* / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D007525:Isoelectric Focusing; D008969:Molecular Sequence Data; D009245:NADH Dehydrogenase / Q000378:metabolism*; D016354:Rhodobacter capsulatus / Q000201:enzymology*; D017386:Sequence Homology, Amino Acid; D012995:Solubility
chemical_list: D009245:NADH Dehydrogenase; D008058:Dihydrolipoamide Dehydrogenase