Anusree, Murali; Wendisch, Volker F.; Nampoothiri, K. Madhavan
초록
<P><B>Abstract</B></P> <P>The aim of the present study is the development of a consolidated bioprocess for the production of lysine with recombinant <I>Corynebacterium glutamicum</I> DM1729 strains expressing endoglucanase and β-glucosidase genes. Here, the endoglucanase genes from <I>Xanthomonas campestris</I> XCC3521 and XCC2387 and betaglucosidase gene from <I>Saccharophagus degradans</I> Sde1394 were cloned in <I>C. glutamicum</I> DM1729 and expressed either extracellularly or on cell surface. The highest β-glucosidase activity of 9±0.5U/OD<SUB>600</SUB> of 1 and endoglucanase activity of 5.5±0.8U was obtained in <I>C. glutamicum</I> DM 1729 (pVWEx1-TAT<I>XCC2387</I>) (pEKEx3-<I>PorC-Sde1394</I>) when cellobiose (20g/L) alone or in combination with carboxymethyl cellulose (20g/L) was used as the carbon sources respectively. The overall efforts resulted in a lysine titre of 5.9±0.5mM. The ability of the constructs to utilize carboxymethyl cellulose and cellobiose for growth and amino acid production proves the concept of utilization of <I>C. glutamicum</I> as a biocatalyst in the lignocellulosic biorefinery.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Heterologous expression of endoglucanase and β-glucosidase genes in <I>Corynebacterium glutamicum</I> DM1729. </LI> <LI> Simultaneous saccharification and fermentation of carboxymethyl cellulose and cellobiose to lysine. </LI> <LI> Hydrolysis of sugarcane tops and rice straw by recombinant enzymes to reducing sugars. </LI> <LI> Initial step toward direct conversion of lignocellulosic biomass to amino acid. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>