A bacterial nitric oxide synthase from a Nocardia species.
Nitric oxide synthase (EC 1.14.23) was discovered in a Nocardia species. The bacterial nitric oxide synthase was purified as much as 380 fold by affinity chromatography over 2',5'-ADP-agarose. The partially purified enzyme required NADPH, O2, CA++, FAD, FMN, and tetrahydrobiopterin as cofactors in the conversion of L-arginine to L-citrulline and nitric oxide. The apparent Km for L-arginine was determined to be 8.2 microM, and the Vmax was 840 nmole NADPH consumed/min/mg protein. The enzyme was competetively inhibited by NG-nitro-arginine with an apparent Ki of 14.6 microM. The experimental evidence provides confirmation of the first microbial nitric oxide synthase in microorganisms.
Chen
Y
Y
Division of Medicinal and Natural Products Chemistry, College of Pharmacy, University of Iowa, Iowa City 52242.
Rosazza
J P
JP
D000594:Amino Acid Oxidoreductases / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism; D001120:Arginine / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D001708:Biopterins / Q000031:analogs & derivatives / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D002956:Citrulline / Q000378:metabolism; D005486:Flavin Mononucleotide / Q000494:pharmacology; D005182:Flavin-Adenine Dinucleotide / Q000494:pharmacology; D009249:NADP / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism; D019001:Nitric Oxide Synthase; D019335:Nitroarginine; D009615:Nocardia / Q000201:enzymology*; D010100:Oxygen / Q000494:pharmacology
D005182:Flavin-Adenine Dinucleotide; D019335:Nitroarginine; D001708:Biopterins; D002956:Citrulline; D009569:Nitric Oxide; D009249:NADP; D005486:Flavin Mononucleotide; D001120:Arginine; D019001:Nitric Oxide Synthase; D000594:Amino Acid Oxidoreductases; C003402:sapropterin; D010100:Oxygen; D002118:Calcium