Bi-functional fusion enzyme EG-M-Xyn displaying endoglucanase and xylanase activities and its utility in improving lignocellulose degradation.
| Author | |
|---|---|
| Abstract |    :  
                  In this study, the gene fusion of endoglucanase (EG, one of cellulases) from Teleogryllus emma and xylanase (Xyn, one of hemicellulases) from Thermomyces lanuginosus was constructed to generate a fusion enzyme (EG-M-Xyn). Through the expression and purification by ultrafiltration and size-exclusion chromatography, the purified EG-M-Xyn had a molecular weight of 75.5 kDa and exhibited the specific activity of CMCase and xylanase as 306.8 U/mg and 1227.3 U/mg, respectively. The Km values (CMC and beechwood xylan) were 6.8 and 60.6 mg mL-1 while catalytic efficiency (kcat/Km) values of CMCase and xylanase were 3280 and 38,797 min-1 mg-1 mL, respectively. EG-M-Xyn exerted great properties for its great potential in improving the enzymatic hydrolysis of lignocellulosics to produce fermentable sugars. First, EG-M-Xyn showed mild reaction pH and temperature of 5.5 and 50 °C, respectively. Secondly, EG-M-Xyn exhibited great heat tolerance of T1/2 values of 173 (CMCase) and 693 min (xylanase). Lastly and most importantly, application of EG-M-Xyn in combination with Ctec2 (commercial enzyme) in the saccharification led to a 10-20% net increase in fermentable sugars liberated from pretreated rice straw in comparison to the Ctec2 alone group. In conclusion, EG-M-Xyn had great potential in generating fermentable sugars from renewable agro-residues for biofuel and fine chemical industry.  | 
        
| Year of Publication |    :  
                  2018 
             | 
        
| Journal |    :  
                  International journal of biological macromolecules 
             | 
        
| Date Published |    :  
                  2018 
             | 
        
| ISSN Number |    :  
                  0141-8130 
             | 
        
| URL |    :  
                  http://linkinghub.elsevier.com/retrieve/pii/S0141-8130(17)34796-7 
             | 
        
| DOI |    :  
                  10.1016/j.ijbiomac.2018.01.080 
             | 
        
| Short Title |    :  
                  Int J Biol Macromol 
             | 
        
| Download citation |