Regulation and Interconversion of the Potassium Transport Systems of Saccharomyces Cerevisiae as Revealed by Rubidium Transport

Eur J Biochem. 1986 Jan 15;154(2):307-11. doi: 10.1111/j.1432-1033.1986.tb09398.x.

Abstract

The kinetics of Rb+ transport in Saccharomyces cerevisiae depended on the K+ content of the cells and on K+ starvation, as follows. In cells with normal K+ (grown at millimolar K+), Rb+ transport was regulated by internal K+. The loss of K+ first decreased the Km and later increased the Vmax of Rb+ transport. K+ starvation of normal-K+ cells for 4-5 h decreased the Km of Rb+ transport below the minimum observed after K+ loss. During this time Eadie-Hofstee plots of Rb+ transport suggest that the existing system was converted into a new one with a higher affinity. Growth at 10 microM K+ only required the system triggered by K+ loss, and the system expressed in K+-starved cells was not expressed under these conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphate / physiology
  • Ammonia / pharmacology
  • Biological Transport
  • Energy Metabolism
  • Fungal Proteins / biosynthesis
  • Potassium / metabolism*
  • Potassium / physiology
  • Rubidium / metabolism*
  • Saccharomyces cerevisiae / growth & development
  • Saccharomyces cerevisiae / metabolism*

Substances

  • Fungal Proteins
  • Ammonia
  • Adenosine Triphosphate
  • Rubidium
  • Potassium