1ZM1

Crystal structures of complex F. succinogenes 1,3-1,4-beta-D-glucanase and beta-1,3-1,4-cellotriose

Summary for 1ZM1

• Entry DOI: 10.2210/pdb1zm1/pdb
• Related: 1MVE
• Descriptor: Beta-glucanase, beta-D-glucopyranose-(1-4)-beta-D-glucopyranose-(1-3)-beta-D-glucopyranose, CALCIUM ION, ... (4 entities in total)
• Functional Keywords: glucanase/1, 3-1, 4-beta-d-glucanase, beta-1, 4-cellotriose (cltr), active cleft, hydrolase
• Biological source: Fibrobacter succinogenes
• Total number of polymer chains: 2
• Total formula weight: 55321.33

Authors

Tsai, L.C.,Shyur, L.F.,Cheng, Y.S.,Lee, S.H. (deposition date: 2005-05-10, release date: 2006-05-10, Last modification date: 2023-11-15)

Primary citation

Tsai, L.C.,Shyur, L.F.,Cheng, Y.S.,Lee, S.H.
Crystal structure of truncated Fibrobacter succinogenes 1,3-1,4-beta-D-glucanase in complex with beta-1,3-1,4-cellotriose
J.Mol.Biol., 354:642-651, 2005

PubMed Abstract: Fibrobacter succinogenes 1,3-1,4-beta-D-glucanase (Fsbeta-glucanase) catalyzes the specific hydrolysis of beta-1,4 glycosidic bonds adjacent to beta-1,3 linkages in beta-D-glucans or lichenan. This is the first report to elucidate the crystal structure of a truncated Fsbeta-glucanase (TFsbeta-glucanase) in complex with beta-1,3-1,4-cellotriose, a major product of the enzyme reaction. The crystal structures, at a resolution of 2.3 angstroms, reveal that the overall fold of TFsbeta-glucanase remains virtually unchanged upon sugar binding. The enzyme accommodates five glucose residues, forming a concave active cleft. The beta-1,3-1,4-cellotriose with subsites -3 to -1 bound to the active cleft of TFsbeta-glucanase with its reducing end subsite -1 close to the key catalytic residues Glu56 and Glu60. All three subsites of the beta-1,3-1,4-cellotriose adopted a relaxed C(1)4 conformation, with a beta-1,3 glycosidic linkage between subsites -2 and -1, and a beta-1,4 glycosidic linkage between subsites -3 and -2. On the basis of the enzyme-product complex structure observed in this study, a catalytic mechanism and substrate binding conformation of the active site of TFsbeta-glucanase is proposed.

PubMed: 16246371
DOI: 10.1016/j.jmb.2005.09.041

Experimental method

X-RAY DIFFRACTION (2.3 Å)