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Structural insights into ChpT, an essential dimeric histidine phosphotransferase regulating the cell cycle in Caulobacter crescentus.

ABSTRACT: Two-component and phosphorelay signal-transduction proteins are crucial for bacterial cell-cycle regulation in Caulobacter crescentus. ChpT is an essential histidine phosphotransferase that controls the activity of the master cell-cycle regulator CtrA by phosphorylation. Here, the 2.2 Å resolution crystal structure of ChpT is reported. ChpT is a homodimer and adopts the domain architecture of the intracellular part of class I histidine kinases. Each subunit consists of two distinct domains: an N-terminal helical hairpin domain and a C-terminal ?/? domain. The two N-terminal domains are adjacent within the dimer, forming a four-helix bundle. The ChpT C-terminal domain adopts an atypical Bergerat ATP-binding fold.

SUBMITTER: Fioravanti A

PROVIDER: S-EPMC3433190 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Structural insights into ChpT, an essential dimeric histidine phosphotransferase regulating the cell cycle in Caulobacter crescentus.

Fioravanti Antonella A Clantin Bernard B Dewitte Frédérique F Lens Zoé Z Verger Alexis A Biondi Emanuele G EG Villeret Vincent V

Acta crystallographica. Section F, Structural biology and crystallization communications 20120829 Pt 9

Two-component and phosphorelay signal-transduction proteins are crucial for bacterial cell-cycle regulation in Caulobacter crescentus. ChpT is an essential histidine phosphotransferase that controls the activity of the master cell-cycle regulator CtrA by phosphorylation. Here, the 2.2 Å resolution crystal structure of ChpT is reported. ChpT is a homodimer and adopts the domain architecture of the intracellular part of class I histidine kinases. Each subunit consists of two distinct domains: an N ...[more]

PMID: 22949187

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