Effects of K+ and other monovalent cations on yeast mitochondria.
In mitochondria from Saccharomyces cerevisiae and in the presence of ethanol or NADH, K+ or Na+ increased the rate of O2 uptake in states 3 and uncoupled as well as in sonicated mitochondria. The respiratory control, the ADP:O ratio and the synthesis of ATP also increased. ATP hydrolysis by sonicated mitochondria increased depending on the cation added as follows: K+ = NH4+ = Rb+ Na+ Li+. This correlated with the ionic radii of the cations. Monovalent cations increased the activity of: 1) F1F0ATPase which was sensitive to cation size and 2) complex I of the respiratory chain, which seemed to regulate the rate of oxidative phosphorylation, but did not discriminate between K+ or Na+.
Uribe
S
S
Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, D.F.
Sánchez
N
N
Peña
A
A
D000255:Adenosine Triphosphate / Q000378:metabolism; D000641:Ammonia / Q000494:pharmacology; D008094:Lithium / Q000494:pharmacology; D008928:Mitochondria / Q000201:enzymology / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism; D010766:Phosphorylation; D011188:Potassium / Q000494:pharmacology*; D006180:Proton-Translocating ATPases / Q000378:metabolism; D012413:Rubidium / Q000494:pharmacology; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism*; D012964:Sodium / Q000494:pharmacology
D000641:Ammonia; D000255:Adenosine Triphosphate; D008094:Lithium; D012964:Sodium; D006180:Proton-Translocating ATPases; D012413:Rubidium; D011188:Potassium; D010100:Oxygen