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Structural basis for the reversibility of proton pyrophosphatase.

ABSTRACT: Proton Pyrophosphatase (H+-PPase) is an evolutionarily conserved enzyme regarded as a bona fide vacuolar marker. However, H+-PPase also localizes at the plasma membrane of the phloem, where, evidence suggests that it functions as a Pyrophosphate Synthase and participates in phloem loading and photosynthate partitioning. We believe that this pyrophosphate synthesising function of H+-PPase is fundamentally rooted to its molecular structure, and here we postulate, on the basis of published crystal structures of membrane-bound pyrophosphatases, a plausible mechanism of pyrophosphate synthesis.

SUBMITTER: Regmi KC

PROVIDER: S-EPMC5257167 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Structural basis for the reversibility of proton pyrophosphatase.

Regmi Kamesh C KC Pizzio Gaston A GA Gaxiola Roberto A RA

Plant signaling & behavior 20161001 10

Proton Pyrophosphatase (H+-PPase) is an evolutionarily conserved enzyme regarded as a bona fide vacuolar marker. However, H+-PPase also localizes at the plasma membrane of the phloem, where, evidence suggests that it functions as a Pyrophosphate Synthase and participates in phloem loading and photosynthate partitioning. We believe that this pyrophosphate synthesising function of H+-PPase is fundamentally rooted to its molecular structure, and here we postulate, o ...[more]

PMID: 27611445

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