Reduced Nicotinamide Adenine Dinucleotide and Reduced Nicotinamide Adenine Dinucleotide Phosphate Diaphorase Activity in Human Polymorphonuclear Leukocytes
AUTOR(ES)
DeChatelet, Lawrence R.
RESUMO
Total reduced nicotinamide adenine dinucleotide (NADH) and reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase activities were examined in human neutrophils. Approximately two-thirds of each enzyme activity was located in the granule fraction with the remainder in the soluble. The activities in a 27,000 × g supernatant from a sonic extract of human polymorphonuclear leukocytes were characterized. Both NADH and NADPH diaphorase were insensitive to cyanide and azide and showed greater activity at acid pH. Km values for nitroblue tetrazolium were not markedly different (33 μM with NADH and 12 μM with NADPH), but there was a 40-fold difference in Km for the reduced pyridine nucleotides (10 μM with NADH and 400 μM for NADPH). Since the intracellular concentration of both nucleotides is estimated to be about 50 μM, it is much more likely, from a kinetic argument, that the respiratory burst of phagocytosis is intiated by the oxidation of NADH rather than of NADPH.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=422986Documentos Relacionados
- Allosteric Transformation of Reduced Nicotinamide Adenine Dinucleotide (Phosphate) Oxidase Induced by Phagocytosis in Human Polymorphonuclear Leukocytes
- Nicotinamide Adenine Dinucleotide Glycohydrolase Activity in Guinea Pig Polymorphonuclear Leukocytes
- Escherichia coli Mutant with Elevated Nicotinamide Adenine Dinucleotide Phosphate (Reduced) Oxidase Activity
- Measurement of nicotinamide adenine dinucleotide & nicotinamide adenine dinucleotide phosphate in tomato leaves 1
- Correlation Between Reduced Nicotinamide Adenine Dinucleotide Phosphate Levels and Morphological Changes in Neurospora crassa
