Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
Compound
Query: UNIPROT:P80404 (
GABA transaminase
)
786
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
4-Aminobutyrate transaminase (
GABA-T
, 4-aminobutyrate alpha-oxoglutrate aminotransferase, EC 2.6.1.19) is an enzyme that inactivates the inhibitory neurotransmitter, GABA, but its pharmacological function is uncertain. Two forms of guiena pig brain
GABA-T
were isolated by
DEAE
-cellulose chromatography and designated as
GABA-T
-I and II, corresponding to an anionic and a cationic form. The enzymes were inhibited by high concentrations of a cationic form. The enzymes were inhibited by high concentrations of alpha-oxoglutrate (alpha-KG). Kinetic consists for GABA, when determined at pH 7.9 adn 1 mmol/l alpha-KG, were 0.74 mmol/l.
GABA-T
activity was inhibited by chloride and other anions. Kinetic analysis revealed chloride ion as a conpetitive inhibitor against GABA, but the Ki values differed among
GABA-T
-I and II (Ki equals 120 and 60 mmol/l, respectively). Similar degrees of difference were observed with acetate and lactate ion. These results suggest that
GABA-T
-II may regulate the GABA level in the inhibitory neurons and may play a similar functional role as that exhibited by monoamine oxidase in other synapses.
...
PMID:Two forms of 4-aminobutyrate transaminase in guinea pig brain. 23 77