Temperature dependence of solute transport and enzyme activities in hog renal brush border membrane vesicles.
Biochim Biophys Acta
; 648(2): 247-53, 1981 Nov 06.
Article
em En
| MEDLINE
| ID: mdl-7306539
ABSTRACT
The temperature dependence of sodium-dependent and sodium-independent D-glucose and phosphate uptake by renal brush border membrane vesicles has been studied under tracer exchange conditions. For sodium-dependent D-glucose and phosphate uptake, discontinuities in the Arrhenius plot were observed. The apparent activation energy for both processes increased at least 4-fold with decreasing temperature. The most striking change in the slope of the Arrhenius plot occurred between 12 and 15 degrees C. The sodium-independent uptake of D-glucose and phosphate showed a linear Arrhenius plot over the temperature range tested (35-5 degrees C). The behavior of the transport processes was compared to the temperature dependence of typical brush border membrane enzymes. Alkaline phosphatase as intrinsic membrane protein showed a nonlinear Arrhenius plot with a transition temperature at 12.4 degrees C. Aminopeptidase M, an extrinsic membrane protein exhibited a linear Arrhenius plot. These data indicate that the sodium-glucose and sodium-phosphate cotransport systems are intrinsic brush border membrane proteins, and that a change in membrane organization alters the activity of a variety of intrinsic membrane proteins simultaneously.
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Base de dados:
MEDLINE
Assunto principal:
Fosfatos
/
Sódio
/
Membrana Celular
/
Glucose
/
Córtex Renal
/
Microvilosidades
Limite:
Animals
Idioma:
En
Ano de publicação:
1981
Tipo de documento:
Article