title: Construction of a 3D model of CP12, a protein linker.
abstract: The chloroplast protein CP12 is known to play a leading role in a complex formation with the enzymes GAPDH and PRK. As a preliminary step towards the understanding of the complex formation mechanism and the exact role of this protein linker, a comparative modelling of the CP12 protein of the green alga Chlamydomonas reinhardtii was performed. Because of the very few structural information and poor template similarities, the derivation of the model consisted in an iterative trial-and-error procedure using the comparative modelling program MODELLER, the following three structure validation programs PROCHECK, PROSA, and WHATIF, and molecular mechanics energy refinement of the model using the program CHARMM. The analysis of the final model reveals a scaffold of key residues that is believed to be essential in the folding mechanism and that coincides with the residues conserved throughout the CP12 family. Our results suggest that this protein is a typical disordered protein. Finally, the various mechanisms by which the CP12 protein can self-interact or binds to other enzymes are discussed in light of its modelled structure and characteristics.
authors.affiliation: Laboratoire de Biochimie et Génétique Moléculaire, Université de La Réunion, 15 Avenue René Cassin, 97715 Saint-Denis Messag Cedex 09, La Réunion, France.
authors.forename: Fabrice
authors.initials: F
authors.lastname: Gardebien
authors.forename: Rajesh R
authors.initials: RR
authors.lastname: Thangudu
authors.forename: Brigitte
authors.initials: B
authors.lastname: Gontero
authors.forename: Bernard
authors.initials: B
authors.lastname: Offmann
mesh_terms: D020418:Algal Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D016825:Chlamydomonas reinhardtii / Q000235:genetics / Q000378:metabolism*; D002736:Chloroplasts / Q000378:metabolism; D003198:Computer Simulation; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid
chemical_list: D020418:Algal Proteins; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases