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H+ -PPases: a tightly membrane-bound family
M Baltscheffsky1, A Schultz, H Baltscheffsky
1Department of Biochemistry, Arrhenius Laboratories, Stockholm, Sweden. meg@biokemi.su.se
FEBS Letters
|September 3, 1999
Summary
The proton-pumping inorganic pyrophosphatase (H+-PPase) is a vital alternative to H+-ATP synthase in energy production. Research reveals a conserved family of H+-PPase enzymes across bacteria, algae, and plants, aiding functional analysis.
Area of Science:
- Biochemistry
- Molecular Biology
- Enzymology
Context:
- The proton-pumping inorganic pyrophosphatase (H+-PPase) is the sole known alternative to H+-ATP synthase for biological electron transport phosphorylation.
- The earliest identified H+-PPase is the membrane-bound H+-PPi synthase from Rhodospirillum rubrum.
Purpose:
- To review and compare the primary structures of H+-PPases.
- To analyze the homology between bacterial, algal, and higher plant H+-PPases.
- To identify functionally significant entities within the H+-PPase family.
Summary:
- Cloning of higher plant vacuolar H+-PPase genes revealed a family of highly similar proton-pumping enzymes.
- Bacterial H+-PPi synthase and algal vacuolar H+-PPases show homology to this plant H+-PPase family.
- Comparative analysis of prokaryotic, algal, and plant H+-PPases highlights evolutionary divergence and conserved functional domains.
Impact:
- Facilitates a deeper understanding of energy transduction mechanisms in diverse organisms.
- Provides insights into the evolution and functional diversification of proton-pumping enzymes.
- Establishes a comparative framework for future research on H+-PPase structure-function relationships.
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