2KYC
solution structure of Ca-free chicken parvalbumin 3 (CPV3)
Summary for 2KYC
| Entry DOI | 10.2210/pdb2kyc/pdb |
| Related | 2KYF |
| NMR Information | BMRB: 16945 |
| Descriptor | Parvalbumin, thymic CPV3 (1 entity in total) |
| Functional Keywords | ef-hand protein, parvalbumin, calcium binding protein |
| Biological source | Gallus gallus (bantam,chickens) |
| Total number of polymer chains | 1 |
| Total formula weight | 11972.28 |
| Authors | Henzl, N.T.,Tanner, J.J.,Tan, A. (deposition date: 2010-05-23, release date: 2011-01-12, Last modification date: 2024-05-15) |
| Primary citation | Henzl, M.T.,Tanner, J.J.,Tan, A. Solution structures of chicken parvalbumin 3 in the Ca(2+) -free and Ca(2+) -bound states. Proteins, 79:752-764, 2011 Cited by PubMed Abstract: Birds express two β-parvalbumin isoforms, parvalbumin 3 and avian thymic hormone (ATH). Parvalbumin 3 from chicken (CPV3) is identical to rat β-parvalbumin (β-PV) at 75 of 108 residues. CPV3 displays intermediate Ca(2+) affinity--higher than that of rat β-parvalbumin, but lower than that of ATH. As in rat β-PV, the attenuation of affinity is associated primarily with the CD site (residues 41-70), rather than the EF site (residues 80-108). Structural data for rat α- and β-parvalbumins suggest that divalent ion affinity is correlated with the similarity of the unliganded and Ca(2+)-bound conformations. We herein present a comparison of the solution structures of Ca(2+)-free and Ca(2+)-bound CPV3. Although the structures are generally similar, the conformations of residues 47 to 50 differ markedly in the two protein forms. These residues are located in the C helix, proximal to the CD binding loop. In response to Ca(2+) removal, F47 experiences much greater solvent accessibility. The side-chain of R48 assumes a position between the C and D helices, adjacent to R69. Significantly, I49 adopts an interior position in the unliganded protein that allows association with the side-chain of L50. Concomitantly, the realignment of F66 and F70 facilitates their interaction with I49 and reduces their contact with residues in the N-terminal AB domain. This reorganization of the hydrophobic core, although less profound, is nevertheless reminiscent of that observed in rat β-PV. The results lend further support to the idea that Ca(2+) affinity correlates with the structural similarity of the apo- and bound parvalbumin conformations. PubMed: 21287610DOI: 10.1002/prot.22915 PDB entries with the same primary citation |
| Experimental method | SOLUTION NMR |
Structure validation
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