Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.7.1.2 (
nitrate reductase
)
3,861
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Assimilatory NADH:
nitrate reductase
from Chlorella is a homotetramer which contains one of each of the prosthetic groups FAD, heme, and Mo6+ per 100-kDa subunit. At low protein concentrations, this tetramer dissociates to a fully active dimer. To further elucidate the possible relationship between quaternary structure and activity, the functional size of
nitrate reductase
was determined by radiation inactivation analysis at high and low concentrations of enzyme where the principal physical species would be either tetrameric or dimeric, respectively. In both cases, the size obtained by this method was 100 kDa, suggesting that each subunit in the tetramer or dimer can function independently. These results confirm earlier results which indicated that the subunits are identical and that each contains a full complement of prosthetic groups. We also found that the functional sizes of the partial activities NADH:cytochrome c reductase, NADH:ferricyanide reductase, and reduced methyl viologen:
nitrate reductase
were fractions (approximately 58 kDa, 47 kDa, and
28 kDa
, respectively) of the subunit molecular mass, suggesting that these domains are functionally independent.
...
PMID:Radiation inactivation of assimilatory NADH:nitrate reductase from Chlorella. Catalytic and physical sizes of functional units. 351 Feb 7
