2uwb
From Proteopedia
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CRYSTAL STRUCTURE OF THE NASTURTIUM SEEDLING MUTANT XYLOGLUCANASE ISOFORM NXG1-DELTA-YNIIG
Overview
High-resolution, three-dimensional structures of the archetypal glycoside, hydrolase family 16 (GH16) endo-xyloglucanases Tm-NXG1 and Tm-NXG2 from, nasturtium (Tropaeolum majus) have been solved by x-ray crystallography., Key structural features that modulate the relative rates of substrate, hydrolysis to transglycosylation in the GH16 xyloglucan-active enzymes, were identified by structure-function studies of the recombinantly, expressed enzymes in comparison with data for the strict xyloglucan, endo-transglycosylase Ptt-XET16-34 from hybrid aspen (Populus tremula x, Populus tremuloides). Production of the loop deletion variant, Tm-NXG1-DeltaYNIIG yielded an enzyme that was structurally similar to, Ptt-XET16-34 and had a greatly increased transglycosylation:hydrolysis, ratio. Comprehensive bioinformatic analyses of XTH gene products, together, with detailed kinetic data, strongly suggest that xyloglucanase activity, has evolved as a gain of function in an ancestral GH16 XET to meet, specific biological requirements during seed germination, fruit ripening, and rapid wall expansion.
About this Structure
2UWB is a Single protein structure of sequence from Tropaeolum majus. Full crystallographic information is available from OCA.
Reference
Structural Evidence for the Evolution of Xyloglucanase Activity from Xyloglucan Endo-Transglycosylases: Biological Implications for Cell Wall Metabolism., Baumann MJ, Eklof JM, Michel G, Kallas AM, Teeri TT, Czjzek M, Brumer H 3rd, Plant Cell. 2007 Jun 8;. PMID:17557806
Page seeded by OCA on Wed Jan 23 14:09:03 2008
