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Crystal structure of the C-terminal domain of tubulin-binding cofactor C from Leishmania major.

ABSTRACT: Tubulin-binding cofactor C stimulates GTPase activity and contributes to the release of the heterodimeric ?/?-tubulin from a super-complex of tubulin monomers and two ancillary cofactors. We have determined the 2.2 Å resolution crystal structure of the C-terminal domain of tubulin-binding cofactor C from Leishmania major based on single wavelength anomalous dispersion measurements targeting a selenomethionine derivative. Although previously predicted to consist of two domains the structure is best described as a single domain dominated by a right-handed ?-helix of five turns that form a triangular prism. One face of the prism is covered by the C-terminal residues leaving another face solvent exposed. Comparisons with an orthologous human GTPase activating protein match key residues involved in binding nucleotide and identify the face of the ?-helix fold likely involved in interacting with the ?-tubulin:GTP complex.

SUBMITTER: Barrack KL

PROVIDER: S-EPMC4539340 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Crystal structure of the C-terminal domain of tubulin-binding cofactor C from Leishmania major.

Barrack Keri L KL Fyfe Paul K PK Finney Alex J AJ Hunter William N WN

Molecular and biochemical parasitology 20150514 1

Tubulin-binding cofactor C stimulates GTPase activity and contributes to the release of the heterodimeric α/β-tubulin from a super-complex of tubulin monomers and two ancillary cofactors. We have determined the 2.2 Å resolution crystal structure of the C-terminal domain of tubulin-binding cofactor C from Leishmania major based on single wavelength anomalous dispersion measurements targeting a selenomethionine derivative. Although previously predicted to consist of two domains the structure is be ...[more]

PMID: 25982270

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