Vacuolar H(+)-pyrophosphatase

Biochim Biophys Acta. 2000 May 1;1465(1-2):37-51. doi: 10.1016/s0005-2736(00)00130-9.

Abstract

The H(+)-translocating inorganic pyrophosphatase (H(+)-PPase) is a unique, electrogenic proton pump distributed among most land plants, but only some alga, protozoa, bacteria, and archaebacteria. This enzyme is a fine model for research on the coupling mechanism between the pyrophosphate hydrolysis and the active proton transport, since the enzyme consists of a single polypeptide with a calculated molecular mass of 71-80 kDa and its substrate is also simple. Cloning of the H(+)-PPase genes from several organisms has revealed the conserved regions that may be the catalytic site and/or participate in the enzymatic function. The primary sequences are reviewed with reference to biochemical properties of the enzyme, such as the requirement of Mg(2)(+) and K(+). In plant cells, H(+)-PPase coexists with H(+)-ATPase in a single vacuolar membrane. The physiological significance and the regulation of the gene expression of H(+)-PPase are also reviewed.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Amino Acid Sequence
  • Cloning, Molecular
  • Gene Expression Regulation, Enzymologic
  • Gene Expression Regulation, Plant
  • Inorganic Pyrophosphatase
  • Kinetics
  • Membrane Proteins / chemistry
  • Membrane Proteins / metabolism*
  • Models, Molecular
  • Molecular Sequence Data
  • Plant Proteins / chemistry
  • Plant Proteins / metabolism*
  • Pyrophosphatases / chemistry
  • Pyrophosphatases / genetics
  • Pyrophosphatases / metabolism*
  • Sequence Alignment
  • Vacuoles / enzymology*

Substances

  • Membrane Proteins
  • Plant Proteins
  • Pyrophosphatases
  • Inorganic Pyrophosphatase