Reaction of nitric oxide with heme proteins and model compounds of hemoglobin

Journal Article · Tue Jun 30 00:00:00 EDT 1987 · Biochemistry; (United States)

DOI:https://doi.org/10.1021/bi00387a015· OSTI ID:5870710

Sharma, V S; Traylor, T G; Gardiner, R; Mizukami, H

Rates for the reaction of nitric oxide with several ferric heme proteins and model compounds have been measured. The NO combination rates are markedly affected by the presence or absence of distal histidine. Elephant myoglobin in which the E7 distal histidine has been replaced by glutamine reacts with NO 500-1000 times faster than do the native hemoglobins or myoglobins. By contrast, there is not difference in the CO combination rate constants of sperm whale and elephant myoglobins. Studies on ferric model compounds for the R and T states of hemoglobin indicate that their NO combination rate constants are similar to those observed for the combination of CO with the corresponding ferro derivatives. The last observation suggests that the presence of an axial water molecule at the ligand binding site of ferric hemoglobin A prevents it from exhibiting significant cooperativity in its reactions with NO.

• Research Organization: Univ. of California, San Diego, La Jolla
• OSTI ID: 5870710
• Journal Information: Biochemistry; (United States), Vol. 26:13
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
HEME
BIOCHEMICAL REACTION KINETICS
CONFIGURATION INTERACTION
NITRIC OXIDE
GLUTAMINE
HEMOGLOBIN
WATER
AMIDES
AMINO ACIDS
CARBOXYLIC ACIDS
CHALCOGENIDES
GLOBIN
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
KINETICS
NITROGEN COMPOUNDS
NITROGEN OXIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PIGMENTS
PORPHYRINS
PROTEINS
REACTION KINETICS
560300* - Chemicals Metabolism & Toxicology