Cellulose-binding module

Cellulose acetate valerate, 5 421 Cellulose aminoacetates, 5 419 Cellulose-based carbon fibers, 26 735-736 Cellulose-binding module (CBM), 10 282 Cellulose butyrate... 

Lehtio J., Sugiyama J., Gustavsson M., Fransson L., Linder M., and Teeri, T. T. 2003. The binding specificity and affinity determinants of family 1 and family 3 cellulose binding modules. Proc. Natl. Acad. Sci.,100,484-489. 

Fig. 44. Microciystals of Valonia macrophysa cellulose subjected to the action of celluloses (CeI7A from Humicola insolens) consisting of a hydrolytic core, a cellulose-binding module, and a linker that binds the two enzymic components. The reducing end of the cellulose chains is indicated. R, transmission electron microscopy of the cellulose microciystals before and after the enzyme aetion indieates that Cel7A induced a...

Ivanir and Goldbourt have applied solid-state MAS NMR to study CBM3b-Cbh9A (CBM3b), a cellulose binding module protein belonging to family 3b. It is a 146-residue protein having a unique nine-stranded p-sandwich fold, in which 35% of the structure is in a p-sheet... 

Andrade, F.K., Costa, R., Domingues, L., Soares, R., Gama, M., 2010. Improving bacterial cellulose for blood vessel replacement functionalization with a chimeric protein containing a cellulose-binding module and an adhesion peptide. Acta Biomater. 6,4034—4041. 

The development of biotechnological tools for the modification of cellulose fibers may be achieved by combining CBMs, specially cellulose binding modules, with catalytic domains of enzymes that do not normally act on insoluble substrates (e.g. laccase, pectinase or lipase), or with other functional proteins/polypeptides (e.g. hydrophobic or chemically reactive) suitable for the modification of the textile surfaces. Since several CBMs belong to enzymes that act in extreme conditions, the CBM fusion proteins may also improve enzyme stability [103, 135, 157, 158]. Further, CBMs can be fused with bioactive molecules in order to functionalize the fabric tissue. 

In fact, several CBMs were already commercialized as protein expression systems [179]. A cellulose-binding module from C. cellulovorans scaffoldin CbpA protein has been well characterized and commercialized as a fusion domain for protein purification, using a cellulose matrix (Novagen). In such applications, the use of CBMs offers many industrially attractive advantages. Since CBMs adsorb spontaneously to cellulose, very little or no pretreatment of the samples is required prior to immobilization [67, 183]. In addition, some CBMs seem to enhance the solubility of recombinant protein [184, 185]. 

Kavoosi, M Sanaie, N Dismer, F Hubbuch, J Kilburn, DG Haynes, CA. A novel two-zone protein uptake model for affinity chromatography and its application to the description of elution band profiles of proteins fused to a family 9 cellulose binding module affinity tag. Journal of Chromatography A., 2007, 1160(1-2), 137-49. 

Many glycosidases which attack insoluble or partly soluble polysaccharides have a modular construction, in which catalytic domains and carbohydrate binding modules (CBMs) are produced in the same polypeptide. Although there may be occasional exceptions, the main function of these domains appears to be to increase the local concentration of enzyme by loosely absorbing the enzyme to the substrate. CBMs have been classified into families on the basis of amino acid sequence, like the catalytic domains and are on CAZy, the continuously updated website in summer 2007 there were 49 families. Early work had concentrated on the cellulose binding domains (CBDs) previous classifications had referred to CBM (or CBD) Types and used Roman numerals and, to concur with this usage, CBM Families 1-13 are the same as CBM Types 1-XIII. 

The cost of enzyme preparations has been decreasing in recent years however, it continues to affect considerably the price of ethanol obtained from cellulosic raw materials. Increased enzymatic hydrolysis efficiency is one way to reduce the enz)me cost in bioethanol production. Another method is enzyme recycle and reuse. Immobilization of biocatalysts allows for their economic reuse and development of continuous bioprocess. Although immobilization poses problems of substrate accessibility and binding for most endo- and exocellulases, P-glucosidase exhibits characteristics amenable to immobilization, such as activity on soluble substrates and the lack of a carbohydrate-binding module. Among the possible approaches, immobilization of (J-glucosidase is one prospective solution to the problem. 

These effects make cellulose relatively resistant to degradation its degradation speed is extremely slow and necessitates the presence of a consortium of different and specialized enzymes which act cooperatively to break up the surface with binding modules (non-catalytic activity ) and a multimde of synergistically acting P-glucanase modules (catalytic activity). These enzymes have different modes of... 

Recently, Vaaje-Kolstad and colleagues demonstrated that also chitin-binding modules have similar disruption ability. They showed that crystalline chitin is disrupted by a non-catalytic protein, leading to an increase in substrate access for a range of chitinases [63]. The modification of cellulose fibers with CBMs may lead to improved properties of textile and paper pulps [81]. 

Eriksson, J Malmsten, M Tiberg, F CaUisen, TH Damhus, T Johansen, KS. Model cellulose films exposed to H. insolens glucoside hydrolase family 45 endo-cellulase— the effect of the carbohydrate-binding module. Journal of Colloid and Interface Science, 2005,285, 94-9... 

Shpigel, E Roiz, L Goren, R Shoseyov, 0. Bacterial Cellulose-Binding Domain Modulates in Vitro Elongation of Different Plant Cells. Plant Physiol., 1998, 117, 1185-94. 

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