Some Similarities and Differences between Bacterial Chromatophore, Spinach Chloroplast and Yeast Mitochondrial Inorganic Pyrophosphatases
Membrane bound inorganic pyrophosphatases (PPases) appear to play a role in energy metabolism (1,2). PPases are present in bacterial, plant and animal cells and cell organelles. Membrane bound PPases have been found in chromatophores (2), mitochondria (3) and chloroplasts (4). The membrane bound PPase from Rhodospirillum rubrum chromatophores can synthesize PPi (inorganic pyrophosphate) at the expense of light energy (1) and has been described in some detail (2). Mitochondrial membrane bound PPase has been reported to produce PPi as a result of oxidative phosphorylation (3). (Genes encoding soluble PPases of E. coli (5) and yeast (6) have been cloned and characterized). We have studied some similarities and differences between chromatophore, chloroplast and mitochondrial membrane bound PPases.
KeywordsMitochondrial Membrane Coupling Factor Cell Organelle Spinach Chloroplast Yeast Mitochondrion
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- 2.Baltscheffsky, M. and Nyrén, P. (1984) in Bioenergetics (Ernster, L., ed.) pp. 187–2205, Elsevier, AmsterdamGoogle Scholar
- 7.Whately, F.R. and Arnon, D.I. (1963) Methods Enzymol. (Colowick, S.P. and Kaplan, N.O., eds.) vol. 6, pp. 308–313, Acad. Press, N.Y., LondonGoogle Scholar