2bwc
From Proteopedia
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STRUCTURE OF ENDOGLUCANASE 12A (CEL12A) FROM RHODOTHERMUS MARINUS IN COMPLEX WITH CELLOPENTAOSE (5 MINUTE SOAK)
Overview
Cellulose, a polysaccharide consisting of beta-1,4-linked glucose, is the, major component of plant cell walls and consequently one of the most, abundant biopolymers on earth. Carbohydrate polymers such as cellulose are, molecules with vast diversity in structure and function, and a, multiplicity of hydrolases operating in concert are required for, depolymerisation. The bacterium Rhodothermus marinus, isolated from, shallow water marine hot springs, produces a number of, carbohydrate-degrading enzymes including a family 12 cellulase Cel12A. The, structure of R.marinus Cel12A in the ligand-free form (at 1.54 angstroms), and structures of RmCel12A after crystals were soaked in cellopentaose for, two different lengths of time, have been determined. The shorter soaked, complex revealed the conformation of unhydrolysed cellotetraose, while, cellopentaose had been degraded more completely during the longer soak., Comparison of these structures with those of mesophilic family 12, cellulases in complex with inhibitors and substrate revealed that RmCel12A, has a more extensive aromatic network in the active site cleft which, ejects products after hydrolysis. The substrate structure confirms that, during hydrolysis by family 12 cellulases glucose does not pass through a, (2,5)B conformation. Small-angle X-ray scattering analysis of RmCel12A, showed that the enzyme forms a loosely associated antiparallel dimer in, solution, which may target the enzyme to the antiparallel polymer strands, in cellulose.
About this Structure
2BWC is a Single protein structure of sequence from Rhodothermus marinus with and as ligands. Active as Cellulase, with EC number 3.2.1.4 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Dimerisation and an increase in active site aromatic groups as adaptations to high temperatures: X-ray solution scattering and substrate-bound crystal structures of Rhodothermus marinus endoglucanase Cel12A., Crennell SJ, Cook D, Minns A, Svergun D, Andersen RL, Nordberg Karlsson E, J Mol Biol. 2006 Feb 10;356(1):57-71. Epub 2005 Nov 22. PMID:16343530
Page seeded by OCA on Sun Feb 3 10:28:30 2008
