This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Smith, E W Articles by Slayman, C W Search for Related Content PubMed PubMed Citation Articles by Smith, E W Articles by Slayman, C W

 Previous Article  |  Next Article 

J Bacteriol. 1977 February; 129(2): 836-842

Energy-linked potassium uptake by mitochondria from wild-type and poky strains of Neurospora crassa.

ABSTRACT

Mitochondria from Neurospora crassa, like mammalian mitochondria, carry out rapid, energy-linked K+ uptake and H+ release in the presence of valinomycin. The maximal rate of K+ uptake was about 1.0 mumol/mg of mitochondrial protein per min and was seen at valinomycin concentrations in the range of 100 to 200 mug per mg of mitochondrial protein and at K+ concentrations of 4 mM or above. Uptake could be supported either by substrate oxidation or by adenosine 5'-triphosphate (ATP), and was inhibited in the former case by antimycin or cyanide, in the latter case by oligomycin, and in both cases by 2,4-dinitrophenol. Mitochondria from the cytochrome-deficient mutant poky carried out substrate-driven K+ uptake at reduced rates, but oligomycin-sensitive, ATP-driven K+ uptake at rates about 60% greater than those shown by wild-type mitochondria. This result is consistent with the recent finding (Mainzer and Slayman 1976) that poky contains elevated amounts of oligomycin-sensitive mitochondrial adenosine 5'-triphosphatase activity.