Metabolism controls dimerization of the chloroplast FoF1 ATP synthase in Chlamydomonas reinhardtii.
Dimers and oligomers of F-type ATP synthases have been observed previously in mitochondria of various organisms and for the CF(o)F(1) ATP synthase of chloroplasts of Chlamydomonas reinhardtii. In contrast to mitochondria, however, dimers of chloroplast ATP synthases dissociate at elevated phosphate concentration. This suggests a regulation by cell physiological processes. Stable isotope labeling of living cells and blue-native PAGE have been employed to quantitate changes in the ratio of monomeric to dimeric CF(o)F(1) ATP synthase. Chlamydomonas reinhardtii cells were cultivated photoautotrophically in the presence of (15)N and photomixotrophically at natural (14)N abundance, respectively. As compared to photoautotrophic growth, an increased assembly of ATP synthase dimers on the expense of preexisting monomers during photomixotrophic growth was observed, demonstrating a metabolic control of the dimerization process.
Schwassmann
Helena J
HJ
Physical Biochemistry, Department of Chemistry, Darmstadt University of Technology, Petersenstrasse 22, D-64287 Darmstadt, Germany. helena@schwassmann.de
Rexroth
Sascha
S
Seelert
Holger
H
Dencher
Norbert A
NA
D000818:Animals; D016825:Chlamydomonas reinhardtii / Q000201:enzymology*; D002736:Chloroplasts / Q000201:enzymology*; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D007553:Isotope Labeling; D006180:Proton-Translocating ATPases / Q000737:chemistry / Q000378:metabolism*; D015800:Protozoan Proteins / Q000737:chemistry / Q000378:metabolism*
D015800:Protozoan Proteins; D006180:Proton-Translocating ATPases