Evidence for cooperative effects in human liver arginase.
Biochim Biophys Acta
; 701(1): 146-8, 1982 Feb 04.
Article
in En
| MEDLINE
| ID: mdl-7055584
ABSTRACT
The reaction kinetics of human liver arginase (L-arginine amidinohydrolase, EC 3.5.3.1) in terms of arginine concentration is strikingly altered by varying the pH. Lowering the pH from the optimum (9.5) toward a more physiological value (7.5) there is a transition from hyperbolic to sigmoidal kinetics. The cooperative effects are observed in the presence and absence of the product ornithine. Dimers of arginase exhibit typical Michaelis-Menten kinetics even in the presence of ornithine. Dimer-dimer interactions are suggested to explain the kinetic properties of arginase at pH 7.5.
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Database:
MEDLINE
Main subject:
Arginase
/
Liver
Limits:
Humans
Language:
En
Year:
1982
Type:
Article