The nature of the carbohydrate binding module determines the catalytic efficiency of xylanase Z of Clostridium thermocellum

Influence of surface charge, binding site residues and glycosylation on Thielavia terrestris cutinase biochemical characteristics

“…The binding for heterogeneous systems is often expressed as surface adsorption (Hlady and Buijs 1996; Hiraishi et al 2010b; Khan et al 2013). Generally, enzyme adsorption onto heterogeneous polymeric substrates is the fast step and the corresponding enzyme-catalyzed reaction is rate limiting (Fox et al 2012).…”

“…In nature, enzymes that act on heterogeneous substrates are equipped with a binding domain to facilitate substrate binding. Examples include cellulases (Bommarius et al 2014), poly(3-hydroxybutyrate) depolymerases (Hiraishi et al 2010a) and xylanases (Khan et al 2013). Also, engineering the binding domain to improve substrate binding has proved to be an effective tool in enhancing enzyme activity.…”

“…Enzyme binding to polymeric substrates is generally explained by surface adsorption that is a function of electrostatic or hydrophobic interactions of surface amino acid residues with the substrate (Liu et al 2009; Hiraishi et al 2010b; Khan et al 2013). These interactions are pH dependent and, therefore, can influence the pH-activity profile of the enzyme.…”

C-Terminal carbohydrate-binding module 9_2 fused to the N-terminus of GH11 xylanase from Aspergillus niger

“…Both the N-and C-terminal fusions of C2 improved the Xyn thermostability, indicating that the C2 is a thermostabilizing CBM distinct from those binding only to the substrate (Furtado et al 2015;Khan et al 2013;Kittur et al 2003;Mai-Gisondi et al 2015;Mangala et al 2003). In addition, the N-terminal C2 improved enzyme T opt by 2°C.…”

“…T opt and t 1/2 are related but different parameters with the former indicating enzyme adaptivity to a higher temperature and the later, enzyme longevity at a certain temperature. Other CBM fusions also improved catalytic activities of the related enzymes (Furtado et al 2015;Khan et al 2013;Kittur et al 2003;Li et al 2015;Mai-Gisondi et al 2015;Mangala et al 2003;Ye et al 2011). 3; Table 1).…”