Characterization of ATP-diphosphohydrolase from rat mammary gland.
Int J Biochem Cell Biol
; 28(1): 75-9, 1996 Jan.
Article
em En
| MEDLINE
| ID: mdl-8624846
ATP-diphosphohydrolase (or apyrase) hydrolyses nucleoside di- and triphosphates in the presence of millimolar concentration of divalent cations. It is insensitive towards sulfhydryl and aliphatic hydroxyl-selective reagents and to specific inhibitors of ATPases. We present further evidence that ATPase and ADPase activities present in rat mammary gland correspond to apyrase. Two kinetic approaches have been employed, competition plot and chemical modification with group-selective reagents. The M(r) of these activities was determined by 60Co radiation-inactivation. The kinetic approaches employed, competition plot (which discriminate whether competitive reactions occur at the same site) and chemical modification, point to the presence of a single protein which hydrolyses ATP and ADP. The similar M(r) values of ATPase and ADPase activities also support this proposal. ATPase and ADPase activities of mammary gland show a similar sensitivity or insensitivity towards several chemical modifiers. These results suggest that this enzyme is ATP-diphosphohydrolase, also known as apyrase. The results obtained are compared with the ones obtained by us and other authors with the enzyme isolated from other sources.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Apirase
/
Adenosina Trifosfatases
/
Glândulas Mamárias Animais
Limite:
Animals
Idioma:
En
Revista:
Int J Biochem Cell Biol
Assunto da revista:
BIOQUIMICA
Ano de publicação:
1996
Tipo de documento:
Article
País de afiliação:
Chile
País de publicação:
Holanda