1rh9
Family GH5 endo-beta-mannanase from Lycopersicon esculentum (tomato)Family GH5 endo-beta-mannanase from Lycopersicon esculentum (tomato)
Structural highlights
Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe three-dimensional crystal structure of tomato (Lycopersicon esculentum) beta-mannanase 4a (LeMAN4a) has been determined to 1.5 A resolution. The enzyme adopts the (beta/alpha)(8) fold common to the members of glycohydrolase family GH5. The structure is comparable with those of the homologous Trichoderma reesei and Thermomonospora fusca beta-mannanases: There is a conserved three-stranded beta-sheet located near the N terminus that stacks against the central beta-barrel at the end opposite the active site. Three noncanonical beta-helices surround the active site. Similar helices are found in T. reesei but not T. fusca beta-mannanase. By analogy with other beta-mannanases, the catalytic acid/base residue is E204 and the nucleophile residue is E318. The active site cleft of L. esculentum beta-mannanase most closely resembles that of the T. reesei isozyme. A model of substrate binding in LeMAN4a is proposed in which the mannosyl residue occupying the -1 subsite of the enzyme adopts the (1)S(5) skew-boat conformation. Three-dimensional structure of (1,4)-beta-D-mannan mannanohydrolase from tomato fruit.,Bourgault R, Oakley AJ, Bewley JD, Wilce MC Protein Sci. 2005 May;14(5):1233-41. PMID:15840830[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
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