Using directed evolution and site-directed mutagenesis, we have isolated a highly thermostable variant of Aspergillus niger glucoamylase (GA), designated CR2-1. CR2-1 includes the previously described mutations Asn20Cys and Ala27Cys (forming a new disulfide bond), Ser30Pro, Thr62Ala, Ser119Pro, Gly137Ala, Thr290Ala, His391Tyr and Ser436Pro. In addition, CR2-1 includes several new putative therm...

Efficient enzymatic hydrolysis of lignocellulose to fermentable sugars requires a complete repertoire of biomass deconstruction enzymes. Hemicellulases play an important role in hydrolyzing hemicellulose component of lignocellulose to xylooligosaccharides and xylose. Thermostable xylanases have been a focus of attention as industrially important enzymes due to their long shelf life at high temp...

D-Hydantoinase is currently employed as a biocatalyst for the production of optically pure D-amino acids, which are intermediates for the synthesis of semisynthetic antibiotics, peptide hormone, pyrethroids, and pesticides. In the process developed by the Yamada group,1,2 DL-5-substituted hydantoin is asymmetrically hydrolyzed to the N-carbamoyl-D-amino acid by D-specific hydantoinase, and this...

A gene (tap) encoding a thermostable alkaline phosphatase from the thermophilic bacterium Thermus thermophilus XM was cloned and sequenced. It is 1506 bp long and encodes a protein of 501 amino acid residues with a calculated molecular mass of 54.7 kDa. Comparison of the deduced amino acid sequence with other alkaline phosphatases showed that the regions in the vicinity of the phosphorylation s...

Optimal enzyme mixtures of six Trichoderma reesei enzymes and five thermostable enzyme components were developed for the hydrolysis of hydrothermally pretreated wheat straw, alkaline oxidised sugar cane bagasse and steam-exploded bagasse by statistically designed experiments. Preliminary studies to narrow down the optimization parameters showed that a cellobiohydrolase/endoglucanase (CBH/EG) ra...

Genes coding for an endo-pectate lyase, an exo-pectate lyase, and an endopolygalacturonase of Erwinia carotovora subsp. carotovora Ecc71 were cloned in Escherichia coli HB101, using the cosmid pHC79. The products of the cloned pectinase genes paralleled their counterparts in strain Ecc71 in isoelectric mobility, mode of substrate degradation, and ability to macerate potato tuber tissue.

Activities of twelve hydrolytic enzymes in the digestive tract of young rabbits before weaning (4 weeks old) and adult rabbits (3 months old) were measured. The principal digestive enzymes in both groups of rabbits appeared to be amylase (EC 3.2.1.1), maltase (EC 3.2.1.20), pectinase (EC 3.2.1.15) and proteinases. The stomach of young rabbits contained most of the lipolytic activity and 45.7% o...

A study was conducted to study the effects of thermostable phytase supplementation on the growth performance and Ca and P metabolism of broilers for 21 d. 1-day-old Arbor Acres chicks with similar initial body weight were randomly divided into 3 treatments consisting 8 pens of 10 chicks per pen. The control group was given maize-soybean meal basal diet, and the other two groups were fed the bas...