In higher plants, cellulose is synthesized by plasma membrane-localized cellulose synthase complexes (CSCs). Arabidopsis thaliana GH9A1/KORRIGAN1 is a membrane-bound, family 9 glycosyl hydrolase that is important for cellulose synthesis in both primary and secondary cell walls. Most previously identified korrigan1 mutants show severe phenotypes such as embryo lethality; therefore, the role of G...

The occurrence and chemical nature of the cross-links between cellulose microfibrils in outer epidermal cell walls in Pisum sativum cv. Alaska was investigated by rapid-freezing and deep-etching techniques coupled with chemical and enzymatic treatments. The cell wall in the elongating region of epidermal cells was characterized by the absence of the cross-links, while in the elongated region, t...

RESUMO – The use of sugarcane bagasse on enzyme production is a promising alternative for reducing the costs of second generation ethanol. However, a pretreatment step is required to increase cellulose and hemicellulose accessibility. Here, the influence of Liquid Hot Water (LHW) and steam explosion (SE) pretreatments in cultivations with three Aspergillus strains were investigated. A new seque...

The structure of the catalytic core of the endoglucanase V (EGV) from Humicola insolens has been determined by the method of multiple isomorphous replacement at 1.5 A resolution. The final model, refined with X-PLOR and PROLSQ, has a crystallographic R factor of 0.163 (R(free) = 0.240) with deviations from stereochemical target values of 0.012 A and 0.037 degrees for bonds and angles, respectiv...

BACKGROUND Enzymes still comprise a major part of ethanol production costs from lignocellulose raw materials. Irreversible binding of enzymes to the residual substrate prevents their reuse and no efficient methods for recycling of enzymes have so far been presented. Cellulases without a carbohydrate-binding module (CBM) have been found to act efficiently at high substrate consistencies and to r...

Mature endoglucanase E (EGE) from Clostridium thermocellum consists of 780 amino acid residues and has an Mr of 84,016. The N-terminal 334 amino acids comprise a functional catalytic domain. Full-length EGE bound to crystalline cellulose (Avicel) but not to xylan. Bound enzyme could be eluted with distilled water. The capacity of truncated derivatives of the enzyme to bind cellulose was investi...

Two major endoglucanase genes (cel7B and cel5A) were cloned from Penicillium decumbens 114-2 using the method of modified thermal asymmetric interlaced polymerase chain reaction (TAIL-PCR). The result of Southern blotting suggested that P. decumbens has a single copy of the cel5A gene and a single copy of cel7B gene in its chromosomal DNA. The expression level of cel5A and cel7B were determined...

The expression of scaffoldin-anchoring genes and one of the major processive endoglucanases (CelS) from the cellulosome of Clostridium thermocellum has been shown to be dependent on the growth rate. For the present work, we studied the gene regulation of selected cellulosomal endoglucanases and a major xylanase in order to examine the previously observed substrate-linked alterations in cellulos...

Trichoderma longibrachiatum IMI061758 possesses a powerful cellulose enzyme complex composed by different cellobiohydrolase, endoglucanase and /3-glucosidase activities. Recently we have cloned the T. longibrachiatum egll gene encoding a /S-{l,4)-endoglucanase activity (1). From an industrial point of view, we are interested in the design of strains which have an increased egll gene dosage. To ...

Endoglucanase I (EGI) from Trichoderma viride HK-75 catalyzes not only hydrolysis but also transglycosylation reactions of cellooligosaccharides. In order to characterize the important amino acid residues in transglycosylation of EGI, three Tyr, one Leu, and two Glu residues of EGI were replaced by Trp or Asp. The seven resulting EGI, except for L200W, had reduced activities toward carboxymethy...