The addition of Co2+ enhances the catalytic efficiency and thermostability of recombinant glucose isomerase from Thermobifida fusca

Ketoisomeric conversion of glucose derived from microalgal biomasses

“…In general, divalent metal ions play an important role in enhancing or inhibiting of enzyme activity. Accordingly, divalent metal ions such as Ca 2+ , Zn 2+ , Mg 2+ and Mn 2+ with substrate can play an important role in decreasing or enhancing the GI activity by preventing covalent bonding formation in the vicinity of the active site of enzyme [8,30,32]. Herein, the influence of divalent metal ions on Imm-GI activity was investigated at the optimized conditions.…”

“…Since divalent metal ions such as Ca 2+ , Mg 2+ , Zn 2+ and Mn 2+ were known to be important either inhibitors or activators of GI [8,30], effects of various metal ions (1 mM) on Imm-GI enzyme activity were assayed under optimum conditions. To determine the effect of these metal ions on Imm-GI activity, Imm-GI was treated with 5 mM EDTA at room temperature for overnight followed by dialysis against PBS (pH 7.0) with several changes of PBS.…”

“…As described above, Fructose is useful to make higher industrial value products such as high fructose corn syrup (HFCS) [4][5][6]. Since fructose absorption in the intestine is less than glucose [7], it is widely used in the food industry as healthier alternative for glucose [8]. Therefore the isomeric conversion of glucose to fructose is an important process for food manufacturing industry through enhancing the thermostability of glucose isomerase by protein engineering [9].…”

“…GI is one of the critical enzymes with the ability to reversibly convert glucose to fructose in vitro. GI consists of a tetramer, and is known to be affected by metal ions, shown to increase its activity and stability [8]. Moreover, GI is known as Xylose isomerase, which converts d-xylose to d-xylulose in vivo [3,12,20].…”

Pretratamiento de bagazo de caña de azúcar por ozonólisis para obtención de bioalcoholes: Efectos sobre la liberación de azúcares, la generación de inhibidores y las fermentaciones

“…Glucose isomerase activity was determined according to Zhang et al (2013), with modifications. Reaction tubes were composed of: 0.5 mL of 0.2 M sodium phosphate buffer (pH 7.0), 0.2 mL of 1 M Dglucose, 0.1 mL of 0.1 M MgSO 4 Á7H 2 O, 0.1 mL of 0.01 M CoCl 2 Á6H 2 -O, 0.9 mL of distilled water and 0.2 mL of crude enzymatic extract.…”