Na+ + Cl- -gradient-driven, high-affinity, uphill transport of taurine in human placental brush-border membrane vesicles.

نویسندگان

  • Y Miyamoto
  • D F Balkovetz
  • F H Leibach
  • V B Mahesh
  • V Ganapathy
چکیده

Uptake of taurine in human placental brush-border membrane vesicles was greatly stimulated in the presence of an inwardly-directed Na+ + Cl- -gradient and uphill transport of taurine could be demonstrated under these conditions. Na+ as well as Cl- were obligatory for this uptake and both ion gradients could energize the uphill transport. This Na+ + Cl- -gradient-dependent taurine uptake was stimulated by an inside-negative membrane potential, demonstrating the electrogenicity of the process. The uptake system was highly specific for beta-amino acids and the Km of the system for taurine was 6.5 +/- 0.4 microM.

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عنوان ژورنال:
  • FEBS letters

دوره 231 1  شماره 

صفحات  -

تاریخ انتشار 1988