The reactions of some aromatic C-nitroso compounds with haemoglobin
- 30 November 1960
- journal article
- research article
- Published by Portland Press Ltd. in Biochemical Journal
- Vol. 77 (3), 519-526
- https://doi.org/10.1042/bj0770519
Abstract
Reduced hemoglobin combines successively with 4 molecules of nitrosobenzene and the nitrosotoluenes. The rate constants for the combination of the first molecule of ligand at pH 9-1 and 20[degree] are (M-1 sec.-l): nitrosobenzene, 9.2 x 104; o-nitroso-toluene, 1.7 x 104; m-nitrosotoluene, 10.5 x 104; p-nitrosotoluene, 10.5 x 104. The 4th molecule to combine does so more rapidly than the first, the average increase in rate is 7-fold. The increase compared with the first molecule is about the same for all 4 compounds. The rate of dissociation of the first molecule of the same compounds from fully saturated hemoglobin has been measured. For nitrosobenzene, and o- and m-nitrosotoluene, the rates lie within the range 0.016-0.032 sec.-l at 20[degree]. The value for p-nitrosotoluene is 0.2 sec.-l. The activation energies for the combination of the first molecule of nitrosobenzene and the dissociation of the first molecule of nitrosobenzene give a normal value to the frequency factor in both cases. The rates of combination of the 4 nitroso compounds with myoglobin are numerically equal to those for the combination of the first molecule with reduced haemoglobin, with the exception of o-nitrosotoluene which combines with myoglobin almost as fast as do the other compounds.Keywords
This publication has 9 references indexed in Scilit:
- Some observations on the kinetics of the reactions with gases of natural and reconstituted haemoglobinsBiochemical Journal, 1960
- The kinetics of the reactions of sheep haemoglobin with iso cyanidesProceedings of the Royal Society of London. B. Biological Sciences, 1960
- [Cyclic process of hemoglobin formation through benzylphenylhydroxylamine and benzalphenylnitrone].1958
- The kinetics of dissociation of the first ligand molecule from fully saturated carboxyhaemoglobin and nitric oxide haemoglobin in sheep blood solutionsProceedings of the Royal Society of London. B. Biological Sciences, 1957
- The determination of the velocity constants of the four successive reactions of carbon monoxide with sheep haemoglobinProceedings of the Royal Society of London. B. Biological Sciences, 1957
- The kinetics of dissociation of the first oxygen molecule from fully saturated oxyhaemoglobin in sheep blood solutionsProceedings of the Royal Society of London. B. Biological Sciences, 1955
- The reaction of haemoglobin and some of its derivatives with p-iodophenylhydroxylamine and p-iodonitrosobenzeneBiochemical Journal, 1954
- The Combining Power of Hemoglobin for Alkyl Isocyanides, and the Nature of the Heme-Heme Interactions in HemoglobinScience, 1951
- The kinetics of hœmoglobin IV- General methods and theoretical basis for the reactions with carbon monoxideProceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character, 1934