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:2.7.1.1 (
hexokinase
)
5,274
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Pyridoxal phosphate can act as a specific photosensitizer for amino acid residues in rabbit muscle and spinach leaf aldolases, but the residues affected depend on the pH of the reaction. Below pH 8 one histidine residue per enzyme subunit is destroyed; above pH 8.5 there is little loss of histidine, and photoinactivation is associated with the destruction of specific tyrosine residues, particularly the COOH-terminal residues.
Pyridoxal
and 4-pyridinecarboxaldehyde are much less effective than pyridoxal phosphate at neutral pH, but are similar to pyridoxal phosphate in their photosensitizing activity at the higher pH. Compounds lacking the aldehyde group or the pyridine ring show little or no activity. A number of other enzymes, including alpha-glycerophosphate dehydrogenase, glucose-6-phosphate dehydrogenase, and yeast
hexokinase
, were also photoinactivated in the presence of pyridoxal phosphate; however, rabbit liver aldolase and two isomerases tested were completely resistant. The results suggest that certain enzymes, including rabbit muscle and spinach aldolases, but not rabbit liver aldolase, contain a specific site which interacts with pyridoxal phosphate, and that the conformation of this site changes in the pH range between 8.0 and 8.5
...
PMID:Photoinactivation of aldolases by pyridoxal phosphate and its analogues. 527 95