Crystal structure determination of Pseudomonas stutzeri A1501 endoglucanase Cel5A: the search for a molecular basis for glycosynthesis in GH5_5 enzymes

In this study, recombinant Ps_Cel5A from Pseudomonas stutzeri A1501, a novel member of the GH5_5 subfamily, was expressed, purified and crystallized. Preliminary experiments confirmed the ability of Ps_Cel5A to catalyze transglycosylation with cellotriose as a substrate. The crystal structure revealed several structural determinants in and around the positive subsites, providing a molecular basis for a better understanding of the mechanisms that promote and favour synthesis rather than hydrolysis. In the positive subsites, two nonconserved positively charged residues (Arg178 and Lys216) were found to interact with cellobiose. This adaptation has also been reported for transglycosylating β -mannanases of the GH5_7 subfamily.
Source: Acta Crystallographica Section D - Category: Biochemistry Authors: Tags: glycosyl hydrolase family 5 cellulases β -1,4-endoglucanases TIM barrel Ps_Cel5A Pst_2494 Pseudomonas stutzeri transglycosylation research papers Source Type: research