An endoglucanase was isolated from cell walls of Zea mays seedlings. Characterization of the hydrolytic activity of this glucanase using model substrates indicated a high specificity for molecules containing intramolecular (1-->3),(1-->4)-beta-d-glucosyl sequences. Substrates with (1-->4)-beta-glucosyl linkages, such as carboxymethylcellulose and xyloglucan were, degraded to a limited extent by...

The objectives of this study were to characterize Fibrobacter succinogenes glycoside hydrolases from different glycoside hydrolase families and to study their synergistic interactions. The gene encoding a major endoglucanase (endoglucanase 1) of F. succinogenes S85 was identified as cel9B from the genome sequence by reference to internal amino acid sequences of the purified native enzyme. Cel9B...

A cosmid gene library was constructed in Escherichia coli from genomic DNA isolated from the ruminal anaerobe Fibrobacter succinogenes AR1. Clones were screened on carboxymethyl cellulose, and 8 colonies that produced large clearing zones and 25 colonies that produced small clearing zones were identified. Southern blot hybridization revealed the existence of at least three separate genes encodi...

A facultative bacterium producing cellulolytic and hemicellulolytic enzymes was isolated from the rumen of a native Korean goat. The bacterium was identified as a Bacillus licheniformis on the basis of biochemical and morphological characteristics and 16S rDNA sequences, and has been designated Bacillus licheniformis JK7. Endoglucanase activities were higher than those of β-glucosidase and xyla...

The Zymomonas mobilis genes for ethanol production have been integrated into the chromosome ofKlebsiella oxytoca M5A1. The best of these constructs, strain P2, produced ethanol efficiently from cellobiose in addition to monomeric sugars. Utilization of cellobiose and cellotriose by this strain eliminated the requirement for external 1-glucosidase and reduced the amount of commercial cellulase n...

Several aminopeptidases of the M42 family have been described as tetrahedral-shaped dodecameric (TET) aminopeptidases. A current hypothesis suggests that these enzymes are involved, along with the tricorn peptidase, in degrading peptides produced by the proteasome. Yet the M42 family remains ill defined, as some members have been annotated as cellulases because of their homology with CelM, form...

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 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...