Biomaterial Database

Interaction of purified NDH-1 from Escherichia coli with ubiquinone analogues. 2002

Pamela David, and Marc Baumann, and Mårten Wikström, and Moshe Finel

Helsinki Bioenergetics Group, Biotechnology Institute, Biocenter 2, University of Helsinki, Helsinki, Finland.

The NADH:ubiquinone oxidoreductase (NDH-1 or Complex I) of Escherichia coli is a smaller version of the mitochondrial enzyme, being composed of 13 protein subunits in comparison to the 43 of bovine heart complex I. The bacterial NDH-1 from an NDH-2-deficient strain was purified using a combination of anion exchange chromatography and sucrose gradient centrifugation. All 13 different subunits were detected in the purified enzyme by either N-terminal sequencing or matrix-assisted laser desorption/ionization time-of-flight mass spectral analysis. In addition, some minor contaminants were observed and identified. The activity of the enzyme was studied and the effects of phospholipid and dodecyl maltoside were characterized. Kinetic analyses were performed for the enzyme in the native membrane as well as for the purified NDH-1, using ubiquinone-1, ubiquinone-2 or decylubiquinone as the electron acceptors. The purified enzyme exhibited between 1.5- and 4-fold increase in the apparent K(m) for these acceptors. Both ubiquinone-2 and decylubiquinone are good acceptors for this enzyme, while affinity of NDH-1 for ubiquinone-1 is clearly lower than for the other two, particularly in the purified state.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009245	NADH Dehydrogenase	A flavoprotein and iron sulfur-containing oxidoreductase that catalyzes the oxidation of NADH to NAD. In eukaryotes the enzyme can be found as a component of mitochondrial electron transport complex I. Under experimental conditions the enzyme can use CYTOCHROME C GROUP as the reducing cofactor. The enzyme was formerly listed as EC 1.6.2.1.	NADH Cytochrome c Reductase,Diaphorase (NADH Dehydrogenase),NADH (Acceptor) Oxidoreductase,NADH Cytochrome c Oxidoreductase,Dehydrogenase, NADH
D009247	NADH, NADPH Oxidoreductases	A group of oxidoreductases that act on NADH or NADPH. In general, enzymes using NADH or NADPH to reduce a substrate are classified according to the reverse reaction, in which NAD+ or NADP+ is formally regarded as an acceptor. This subclass includes only those enzymes in which some other redox carrier is the acceptor. (Enzyme Nomenclature, 1992, p100) EC 1.6.	Oxidoreductases, NADH, NADPH,NADPH Oxidoreductases NADH,Oxidoreductases NADH, NADPH
D009994	Osmolar Concentration	The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.	Ionic Strength,Osmolality,Osmolarity,Concentration, Osmolar,Concentrations, Osmolar,Ionic Strengths,Osmolalities,Osmolar Concentrations,Osmolarities,Strength, Ionic,Strengths, Ionic
D002499	Centrifugation, Density Gradient	Separation of particles according to density by employing a gradient of varying densities. At equilibrium each particle settles in the gradient at a point equal to its density. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Centrifugations, Density Gradient,Density Gradient Centrifugation,Density Gradient Centrifugations,Gradient Centrifugation, Density,Gradient Centrifugations, Density
D002852	Chromatography, Ion Exchange	Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.	Chromatography, Ion-Exchange,Ion-Exchange Chromatography,Chromatographies, Ion Exchange,Chromatographies, Ion-Exchange,Ion Exchange Chromatographies,Ion Exchange Chromatography,Ion-Exchange Chromatographies
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D004795	Enzyme Stability	The extent to which an enzyme retains its structural conformation or its activity when subjected to storage, isolation, and purification or various other physical or chemical manipulations, including proteolytic enzymes and heat.	Enzyme Stabilities,Stabilities, Enzyme,Stability, Enzyme
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D001426	Bacterial Proteins	Proteins found in any species of bacterium.	Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial