RESUMO
The maximal binding of 86Rb was noted when ions of Mg, ATP and Na were present simultaneously. The availability of olytoriside (1-10(-4)M), CaCl2 (1-10(-3)M) and phospholipase A (1-10(-5)M) in the medium and the removal of Na and substitution of ATP for ADP decreased to a different extent the binding of 86Rb.
Assuntos
Bovinos , Córtex Cerebral/metabolismo , Microssomos/metabolismo , Rubídio/metabolismo , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina , Animais , Transporte Biológico Ativo , Cálcio , Glicosídeos Cardíacos , Técnicas In Vitro , Magnésio , Fosfolipases , Potássio , Radioisótopos , SódioRESUMO
On the strength of the study of tryptophan fluorescence of Na+, K+-ATPase preparation a conclusion about conformational changes of the enzume molecule at the level of its tertiary structure is made. The largest changes of intensity and position of fluorescence spectrum consequently the macromolecule structure are discovered at the formation of Mg-ATP-enzyme complex.
Assuntos
Adenosina Trifosfatases , Animais , Encéfalo/enzimologia , Bovinos , Técnicas In Vitro , Magnésio , Microssomos/enzimologia , Conformação Molecular , Potássio , Sódio , Espectrometria de Fluorescência , TriptofanoRESUMO
The influence of calcium ions and fatty acids in the action of direct hemolytic factor and phospholipase A on Mg2+ and Na+, K+-ATPases was investigated. It was established that calcium activates greatly phospholipase A and to a less extent--the direct hemolytic factor. The activity of ATPases is inhibited most effectively by the system consisting of phospholipase A, direct hemolytic factor and Ca2+. Fatty acids can participate in the mechanism of membrane ATPases inhibition.
