The effects of the cations choline, Li+, and the Na+ on the TrkA and Kdp K+ transport systems in Escherichia coli were studied by observing the accumulation of 204Tl+ and K+. Tl+ uptake via the TrkA system was stimulated by Na+ but not Li+ when compared to choline. A similar effect was observed for K+ transport via the TrkA system. On the other hand, Tl+ uptake via the Kdp system was stimulated more by Li+ than by Na+ when compared to choline. In addition, Li+ enhanced the effectiveness of Rb+ as an inhibitor of Tl+ uptake via the Kdp system. Na+, however, was a more effective stimulator of K+ transport via the Kdp system than Li+. We suggest that Na+ may be involved in the mechanisms of K+ transport via the TrkA and Kdp systems in E. coli.
No takes yet. Share an insight, caveat, or question.
Sorensen et al. (1980) studied this question.