Publications by authors named "Igor A Dvortsov"

Carbohydrate-binding modules of the family 54 (CBM54) are characterized by spontaneous rupture of the peptide bond Asn266-Ser267 (numbering corresponds to that of laminarinase Lic16A of Ruminiclostridium thermocellum). As a result of processing, two parts are formed noncovalently connected to each other. Here, to gain insights into the functional significance of the internal cleavage, we made modifications of the family-conserved processing site in CBM54 of Lic16A.

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Optimal catalytic activity of endoglucanase Cel5D from the thermophilic anaerobic bacterium Caldicellulosiruptor bescii requires the presence of a carbohydrate-binding module of family 28, CbCBM28. The binding properties of CbСВМ28 with cello-, laminari-, xylo- and chito-oligosaccharides were studied by isothermal titration calorimetry. CbСВМ28 bound only cello-oligosaccharides comprising at least four glucose residues with binding constants of 2.

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The crystallization and preliminary X-ray diffraction analysis of the carbohydrate-binding module (CBM) from laminarinase Lic16A of the hyperthermophilic anaerobic bacterium Clostridium thermocellum (ctCBM54) are reported. Recombinant ctCBM54 was prepared using an Escherichia coli/pQE30 overexpression system and was crystallized by the hanging-drop vapour-diffusion method. X-ray diffraction data were collected to 2.

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The multi-modular non-cellulosomal endo-1,3(4)-beta-glucanase Lic16A from Clostridium thermocellum contains a so-called X module (denoted as CBMX) near the N terminus of the catalytic module (191-426 aa). Melting of X-module-containing recombinant proteins revealed an independent folding of the module. CBMX was isolated and studied as a separate fragment.

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A cluster of Thermotoga neapolitana genes participating in starch degradation includes the malG gene of sugar transport protein and the aglB gene of cyclomaltodextrinase. The start and stop codons of these genes share a common overlapping sequence, aTGAtg. Here, we compared properties of expression products of three different constructs with aglB from T.

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