Equilibrium binding constants for the group I metal cations with gramicidin-A determined by competition studies and T1+-205 nuclear magnetic resonance spectroscopy. Academic Article uri icon

Overview

abstract

  • The equilibrium binding constants of the Group I metal cations with gramicidin A in aqueous dispersions of lyso-PC have been determined using a combination of competitive binding with the T1+ ion and T1-205 NMR spectroscopy. The values of the binding constants at 34 degrees C are Li (32.2 M-1), Na (36.9 M-1), K (52.6 M-1), Rb (55.9 M-1), and Cs (54.0 M-1). The equilibrium binding constant for the T1+ ion at this temperature is 582 M-1. The relationships between the binding constants, the free energy of the binding process, and the cation selectivity of the gramicidin A channel are discussed.

publication date

  • September 1, 1986

Research

keywords

  • Gramicidin

Identity

PubMed Central ID

  • PMC1329731

Scopus Document Identifier

  • 0022773644

Digital Object Identifier (DOI)

  • 10.1016/S0006-3495(86)83492-0

PubMed ID

  • 2428415

Additional Document Info

volume

  • 50

issue

  • 3