Biomaterial Database

Resolution of distinct selenium-containing formate dehydrogenases from Escherichia coli. 1981

J C Cox, and E S Edwards, and J A DeMoss

Formate dehydrogenase, a component activity of two alternative electron transport pathways in anaerobic Escherichia coli, has been resolved as two distinguishable enzymes. One, which was induced with nitrate reductase as a component of the formate-nitrate reductase pathway, utilized phenazine methosulfate (PMS) in preference to benzyl viologen (BV) as an artificial electron acceptor and appeared to be exclusively membrane-bound. A second formate dehydrogenase, which was induced as a component of the formate hydrogenlyase pathway, appeared to exist both as a membrane-bound form and as a cytoplasmic enzyme; the cytoplasmic activity was resolved completely from the PMS-linked activity on a sucrose gradient. When E. coli was grown in the presence of 75Se-selenite, a 110,000-dalton selenopeptide, previously shown to be a component of the PMS-linked enzyme, was induced and repressed with this activity. In contrast, an 80,000-dalton selenopeptide was induced and repressed with the BV-linked activity and exhibited a distribution similar to the BV-linked formate dehydrogenase in cell fractions and in sucrose gradients. The results indicate that the two formate dehydrogenases are distinguishable on the basis of their artificial electron acceptor specificity, their cellular localization, and the size of their respective selenoprotein components.

UI	MeSH Term	Description	Entries
D008773	Methylphenazonium Methosulfate	Used as an electron carrier in place of the flavine enzyme of Warburg in the hexosemonophosphate system and also in the preparation of SUCCINIC DEHYDROGENASE.	Phenazine Methosulfate,5-Methylphenazinium Methyl Sulfate,5 Methylphenazinium Methyl Sulfate,Methosulfate, Methylphenazonium,Methosulfate, Phenazine,Methyl Sulfate, 5-Methylphenazinium,Sulfate, 5-Methylphenazinium Methyl
D009566	Nitrates	Inorganic or organic salts and esters of nitric acid. These compounds contain the NO3- radical.	Nitrate
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D003593	Cytoplasm	The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)	Protoplasm,Cytoplasms,Protoplasms
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
D005560	Formate Dehydrogenases	Flavoproteins that catalyze reversibly the reduction of carbon dioxide to formate. Many compounds can act as acceptors, but the only physiologically active acceptor is NAD. The enzymes are active in the fermentation of sugars and other compounds to carbon dioxide and are the key enzymes in obtaining energy when bacteria are grown on formate as the main carbon source. They have been purified from bovine blood. EC 1.2.1.2.	Formate Dehydrogenase,Formate Hydrogenlyases,NAD-Formate Dehydrogenase,Dehydrogenase, Formate,Dehydrogenase, NAD-Formate,Dehydrogenases, Formate,Hydrogenlyases, Formate,NAD Formate Dehydrogenase
D000445	Aldehyde Oxidoreductases	Oxidoreductases that are specific for ALDEHYDES.	Aldehyde Oxidoreductase,Oxidoreductase, Aldehyde,Oxidoreductases, Aldehyde
D001594	Benzyl Viologen	1,1'-Bis(phenylmethyl)4,4'-bipyridinium dichloride. Oxidation-reduction indicator.	Viologen, Benzyl
D012643	Selenium	An element with the atomic symbol Se, atomic number 34, and atomic weight 78.97. It is an essential micronutrient for mammals and other animals but is toxic in large amounts. Selenium protects intracellular structures against oxidative damage. It is an essential component of GLUTATHIONE PEROXIDASE.	Selenium-80,Selenium 80