title: Purification of two azoreductases from Escherichia coli K12.
abstract: Two azoreductases (I and II) were purified to homogeneity from extracts of E. coli K12. Azoreductase I was a dimer of two identical subunits of molecular weight 28000 whereas azoreductase II was a monomer of 12,000 molecular weight. Both NADH and NADPH functioned as electron donors for the azoreductases. Azoreductase I and II used Ponceau SX, Tartrazine, Amaranth and Orange II as substrates. Ponceau SX was the best substrate for both the enzymes. However, azoreductase II utilized tartrazine, amaranth and orange II less efficiently than azoreductase I.
authors.affiliation: Department of Biochemistry, University College of Science, Calcutta, India.
authors.forename: D K
authors.initials: DK
authors.lastname: Ghosh
authors.forename: S
authors.initials: S
authors.lastname: Ghosh
authors.forename: P
authors.initials: P
authors.lastname: Sadhukhan
authors.forename: A
authors.initials: A
authors.lastname: Mandal
authors.forename: J
authors.initials: J
authors.lastname: Chaudhuri
mesh_terms: D001391:Azo Compounds; D004926:Escherichia coli / Q000201:enzymology*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008970:Molecular Weight; D009243:NAD / Q000378:metabolism; D009247:NADH, NADPH Oxidoreductases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D009249:NADP / Q000378:metabolism; D009601:Nitroreductases; D011487:Protein Conformation; D013379:Substrate Specificity
chemical_list: D001391:Azo Compounds; D009243:NAD; D009249:NADP; D009247:NADH, NADPH Oxidoreductases; D009601:Nitroreductases; C021106:azoreductase