Two- way dynamics in β-glucosidase catalysis

Publication date: Available online 17 August 2016 Source:Journal of Molecular Catalysis B: Enzymatic Author(s): Sneha Sawant, Sachin Bihrade, Annamma Anil, Harry Gilbert, Arvind Lali Product inhibition of β-glucosidase is considered as one of the central rate limiting steps as it starts accumulation of intermediates responsible for the slowdown of the cellulose hydrolysis. Feedback inhibitions exhibited by glucose and other oligosaccharides on the cellulose hydrolyzing enzyme reduces the rate of hydrolysis bringing the entire process to standstill. However, the exact mechanism of this catalytic slowdown is still elusive. In present study, β-glucosidases were investigated for their activities under high glucose and cellobiose concentrations. β-glucosidases recognizes cellobiose a true substrate and hydrolyzes it resulting in glucose or transglycosylates it to give cellotriose. Our observation highlight that rates of reaction for cellotriose synthesis and glucose formation are mainly concentration driven and are dynamically adjusted based on cellobiose concentration in the reaction system. We therefore conclude that critical concentration of DP2: DP3 influences hydrolysis or transglycosylation and any modulation to this ratio influences the dynamics of β-glucosidases hydrolysis. Graphical abstract

Source: Journal of Molecular Catalysis B: Enzymatic - August 17, 2016 Category: Biochemistry Source Type: research