2ZYK
Crystal structure of cyclo/maltodextrin-binding protein complexed with gamma-cyclodextrin
Replaces: 2DFZSummary for 2ZYK
Entry DOI | 10.2210/pdb2zyk/pdb |
Related PRD ID | PRD_900042 |
Descriptor | Solute-binding protein, Cyclooctakis-(1-4)-(alpha-D-glucopyranose) (3 entities in total) |
Functional Keywords | solute-binding protein, closed form, sugar binding protein |
Biological source | Thermoactinomyces vulgaris |
Total number of polymer chains | 4 |
Total formula weight | 180008.02 |
Authors | Tonozuka, T.,Sogawa, A.,Yamada, M.,Matsumoto, N.,Yoshida, H.,Kamitori, S.,Ichikawa, K.,Mizuno, M.,Nishikawa, A.,Sakano, Y. (deposition date: 2009-01-26, release date: 2009-02-10, Last modification date: 2024-04-03) |
Primary citation | Tonozuka, T.,Sogawa, A.,Yamada, M.,Matsumoto, N.,Yoshida, H.,Kamitori, S.,Ichikawa, K.,Mizuno, M.,Nishikawa, A.,Sakano, Y. Structural basis for cyclodextrin recognition by Thermoactinomyces vulgaris cyclo/maltodextrin-binding protein Febs J., 274:2109-2120, 2007 Cited by PubMed Abstract: The crystal structure of a Thermoactinomyces vulgaris cyclo/maltodextrin-binding protein (TvuCMBP) complexed with gamma-cyclodextrin has been determined. Like Escherichia coli maltodextrin-binding protein (EcoMBP) and other bacterial sugar-binding proteins, TvuCMBP consists of two domains, an N- and a C-domain, both of which are composed of a central beta-sheet surrounded by alpha-helices; the domains are joined by a hinge region containing three segments. gamma-Cyclodextrin is located at a cleft formed by the two domains. A common functional conformational change has been reported in this protein family, which involves switching from an open form to a sugar-transporter bindable form, designated a closed form. The TvuCMBP-gamma-cyclodextrin complex structurally resembles the closed form of EcoMBP, indicating that TvuCMBP complexed with gamma-cyclodextrin adopts the closed form. The fluorescence measurements also showed that the affinities of TvuCMBP for cyclodextrins were almost equal to those for maltooligosaccharides. Despite having similar folds, the sugar-binding site of the N-domain part of TvuCMBP and other bacterial sugar-binding proteins are strikingly different. In TvuCMBP, the side-chain of Leu59 protrudes from the N-domain part into the sugar-binding cleft and orients toward the central cavity of gamma-cyclodextrin, thus Leu59 appears to play the key role in binding. The cleft of the sugar-binding site of TvuCMBP is also wider than that of EcoMBP. These findings suggest that the sugar-binding site of the N-domain part and the wide cleft are critical in determining the specificity of TvuCMBP for gamma-cyclodextrin. PubMed: 17371546DOI: 10.1111/j.1742-4658.2007.05753.x PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (2.5 Å) |
Structure validation
Download full validation report