BioChem - DOS

Enzymatic hydrolysis of cellulose by the cellobiohydrolase domain of CelB from the hyperthermophilic bacterium Caldicellulosiruptor saccharolyticus

Bioresource technology : biomass, bioenergy, biowastes, conversion technologies, biotransformations, production technologies

Park, J.I.; Kent, M.S.; Datta, S.; Holmes, B.M.; Huang, Z.; Simmons, B.A.; Sale, K.L.; Sapra, R.

The celB gene of Caldicellulosiruptor saccharolyticus was cloned and expressed in Escherichia coli to create a recombinant biocatalyst for hydrolyzing lignocellulosic biomass at high temperature. The GH5 domain of CelB hydrolyzed 4-nitrophenyl-&beta;-d-cellobioside and carboxymethyl cellulose with optimum activity at pH 4.7-5.5 and 80<SUP>o</SUP>C. The recombinant GH5 and CBM3-GH5 constructs were both stable at 80<SUP>o</SUP>C with half-lives of 23h and 39h, respectively, and retained >94% activity after 48h at 70<SUP>o</SUP>C. Enzymatic hydrolysis of corn stover and cellulose pretreated with the ionic liquid 1-ethyl-3-methylimidazolium acetate showed that GH5 and CBM3-GH5 primarily produce cellobiose, with product yields for CBM3-GH5 being 1.2- to 2-fold higher than those for GH5. Confocal microscopy of bound protein on cellulose confirmed tighter binding of CBM3-GH5 to cellulose than GH5, indicating that the enhancement of enzymatic activity on solid substrates may be due to the substrate binding activity of CBM3 domain.

2011

Elsevier Applied Science

0960-8524

102

10

pp.5988-5994

10.1016/j.biortech.2011.02.036

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART55986608

[abr] [C2mim][OAc]; 1-ethyl-3-methylimidazolium acetate; [abr] C. sac; Caldicellulosiruptor saccharolyticus; [abr] CV; column volume; [abr] GH; glycoside hydrolase; [abr] pNPC; 4-nitrophenyl-β-d-cellobioside; [abr] pNPG; 4-nitrophenyl-β-d-glucopyranoside; [abr] CBM; carbohydrate binding module; [abr] CMC; carboxymethyl cellulose; Caldicellulosiruptor saccharolyticus; Cellulase; Cellobiohydrolase; Carbohydrate binding module; Hyperthermophile;