We report the systematic survey of the binding free energies at the interface between a carbohydrate binding module(CBM)of Cel7A and the celluloseⅢ_(1)crystal model using grid docking searches and molecular dynamics ...We report the systematic survey of the binding free energies at the interface between a carbohydrate binding module(CBM)of Cel7A and the celluloseⅢ_(1)crystal model using grid docking searches and molecular dynamics simulations.The two hydrophobic crystal surfaces were involved in the distinct energy minima of the binding free energy.The complex models,each with the CBM at the minimum energy position,stably formed in the solution state.The binding free energies of the celluloseⅢ_(1)complex models,based on both static and dynamics states,were comparable to those of the native cellulose complex models.However,the celluloseⅢ_(1)crystal had a larger binding surface,which is compatible with the observed high enzymatic activity of Cel7A for the celluloseⅢ_(1)substrate.展开更多
Napiegrass (Pennisetum purpureum Schumach) was treated with a low-moisture anhydrous ammonia (LMAA) pretreatment by adding an equal weight of water and keeping it under atmospheric ammonia gas at room temperature for ...Napiegrass (Pennisetum purpureum Schumach) was treated with a low-moisture anhydrous ammonia (LMAA) pretreatment by adding an equal weight of water and keeping it under atmospheric ammonia gas at room temperature for four weeks. After the removal of ammonia and washing with water, a simultaneous saccharification and fermentation (SSF) was conducted for the LMAA-pretreated napiergrass (1.33 g) in a buffer solution (8 mL) using a mixture of a cellulase (80 mg) and a xylanase (53 mg) as well as the cell suspension (0.16 mL) of Saccharomyces cerevisiae. Ethanol and xylose resulted in 91.2% and 62.9% yields, respectively. The SSF process was scaled up using LMAA-pretreated napiergrass (100.0 g) to give ethanol (77.2%) and xylose (52.8%). After the removal of ethanol, the pentose fermentation of the SSF solution (40 mL), which contained 1.00 g of xylose, using cell suspension of Escherichia coli KO11 (70 mL) gave 86.3% yield of ethanol. Total ethanol yield reached 68.9% based on xylan (21.4 wt%) and glucan (39.7 wt%) of the LMAA-pretreated napiergrass.展开更多
基金supported by JSPS KAKENHI Grant Number 17K00409。
文摘We report the systematic survey of the binding free energies at the interface between a carbohydrate binding module(CBM)of Cel7A and the celluloseⅢ_(1)crystal model using grid docking searches and molecular dynamics simulations.The two hydrophobic crystal surfaces were involved in the distinct energy minima of the binding free energy.The complex models,each with the CBM at the minimum energy position,stably formed in the solution state.The binding free energies of the celluloseⅢ_(1)complex models,based on both static and dynamics states,were comparable to those of the native cellulose complex models.However,the celluloseⅢ_(1)crystal had a larger binding surface,which is compatible with the observed high enzymatic activity of Cel7A for the celluloseⅢ_(1)substrate.
文摘Napiegrass (Pennisetum purpureum Schumach) was treated with a low-moisture anhydrous ammonia (LMAA) pretreatment by adding an equal weight of water and keeping it under atmospheric ammonia gas at room temperature for four weeks. After the removal of ammonia and washing with water, a simultaneous saccharification and fermentation (SSF) was conducted for the LMAA-pretreated napiergrass (1.33 g) in a buffer solution (8 mL) using a mixture of a cellulase (80 mg) and a xylanase (53 mg) as well as the cell suspension (0.16 mL) of Saccharomyces cerevisiae. Ethanol and xylose resulted in 91.2% and 62.9% yields, respectively. The SSF process was scaled up using LMAA-pretreated napiergrass (100.0 g) to give ethanol (77.2%) and xylose (52.8%). After the removal of ethanol, the pentose fermentation of the SSF solution (40 mL), which contained 1.00 g of xylose, using cell suspension of Escherichia coli KO11 (70 mL) gave 86.3% yield of ethanol. Total ethanol yield reached 68.9% based on xylan (21.4 wt%) and glucan (39.7 wt%) of the LMAA-pretreated napiergrass.
