Summary for 6JHF
Entry DOI | 10.2210/pdb6jhf/pdb |
Related | 6JEQ 6JFJ 6JFX |
Descriptor | Pulullanase, CALCIUM ION, CHLORIDE ION, ... (5 entities in total) |
Functional Keywords | gh13, pullulanase, hydrolase |
Biological source | Paenibacillus barengoltzii |
Total number of polymer chains | 1 |
Total formula weight | 75416.74 |
Authors | Wu, S.W.,Yang, S.Q.,Qin, Z.,You, X.,Huang, P.,Jiang, Z.Q. (deposition date: 2019-02-18, release date: 2019-03-06, Last modification date: 2023-11-22) |
Primary citation | Huang, P.,Wu, S.,Yang, S.,Yan, Q.,Jiang, Z. Structural basis of carbohydrate binding in domain C of a type I pullulanase from Paenibacillus barengoltzii. Acta Crystallogr D Struct Biol, 76:447-457, 2020 Cited by PubMed Abstract: Pullulanase (EC 3.2.1.41) is a well known starch-debranching enzyme that catalyzes the cleavage of α-1,6-glycosidic linkages in α-glucans such as starch and pullulan. Crystal structures of a type I pullulanase from Paenibacillus barengoltzii (PbPulA) and of PbPulA in complex with maltopentaose (G5), maltohexaose (G6)/α-cyclodextrin (α-CD) and β-cyclodextrin (β-CD) were determined in order to better understand substrate binding to this enzyme. PbPulA belongs to glycoside hydrolase (GH) family 13 subfamily 14 and is composed of three domains (CBM48, A and C). Three carbohydrate-binding sites identified in PbPulA were located in CBM48, near the active site and in domain C, respectively. The binding site in CBM48 was specific for β-CD, while that in domain C has not been reported for other pullulanases. The domain C binding site had higher affinity for α-CD than for G6; a small motif (FGGEH) seemed to be one of the major determinants for carbohydrate binding in this domain. Structure-based mutations of several surface-exposed aromatic residues in CBM48 and domain C had a debilitating effect on the activity of the enzyme. These results suggest that both CBM48 and domain C play a role in binding substrates. The crystal forms described contribute to the understanding of pullulanase domain-carbohydrate interactions. PubMed: 32355041DOI: 10.1107/S205979832000409X PDB entries with the same primary citation |
Experimental method | X-RAY DIFFRACTION (1.71 Å) |
Structure validation
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