Reconstitution of active ion transport by the sodium and potassium ion-stimulated adenosine triphosphatase from canine brain.
J Biol Chem
; 250(10): 4022-4, 1975 May 25.
Article
em En
| MEDLINE
| ID: mdl-123920
ABSTRACT
Sodium and potassium ion-stimulated adenosine triphosphatase ((Na+ + K+)-ATPase) was partially purified from canine brain gray matter and reconstituted into vesicles of phosphatidylcholine. A proportion of the enzyme molecules was reconstituted into sealed vesicles with the ATP-hydrolyzing site facing the outside of the vesicles. ATP was added to the outside of the vesicles after they had equilibrated with radioactive tracer, and the resulting active transport of Na+ and K+ was followed. Unlike the purified kidney renal medulla enzyme used in an earlier study, the brain enzyme transports both Na+ and K+(Rb+). Vesicles were made in solutions with different proportions of NaCl and KCl, and over the range studied, an average of 1.8 Rb+ ions were transported for every 3 Na+ ions. When ATP is depleted, the transported ions diffuse back to their equilibrium level in the vesicles.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Potássio
/
Sódio
/
Transporte Biológico Ativo
/
Encéfalo
/
Adenosina Trifosfatases
Limite:
Animals
Idioma:
En
Revista:
J Biol Chem
Ano de publicação:
1975
Tipo de documento:
Article