A novel trifunctional, family GH10 enzyme from Acidothermus cellulolyticus 11B, exhibiting endo-xylanase, arabinofuranosidase and acetyl xylan esterase activities

Abstract

A novel, family GH10 enzyme, Xyn10B from Acidothermus cellulolyticus 11B was cloned and expressed in Escherichia coli. This enzyme was purified to homogeneity by binding to regenerated amorphous cellulose. It had higher binding on Avicel as compared to insoluble xylan due to the presence of cellulose-binding domains, CBM3 and CBM2. This enzyme was optimally active at 70 °C and pH 6.0. It was stable up to 70 °C while the CD spectroscopy analysis showed thermal unfolding at 80 °C. Xyn10B was found to be a trifunctional enzyme having endo-xylanase, arabinofuranosidase and acetyl xylan esterase activities. Its activities against beechwood xylan, p-Nitrophenyl arabinofuranoside and p-Nitrophenyl acetate were found to be 126,480, 10,350 and 17,250 U μmol, respectively. Xyn10B was highly active producing xylobiose and xylose as the major end products, as well as debranching the substrates by removing arabinose and acetyl side chains. Due to its specific characteristics, this enzyme seems to be of importance for industrial applications such as pretreatment of poultry cereals, bio-bleaching of wood pulp and degradation of plant biomass.

Sugarcane/peanut intercropping system improves the soil quality and increases the abundance of beneficial microbes

“…Nonculturable DA111 was found in industrial soft coal slag originating from alum leaching [47]. Culturable Acidothermus promotes the activities of many enzymes, such as endo‐xylanase, arabinofuranosidase, and acetylxylan esterase activities in Acidothermus cellulolyticus 11B [48], and secretes glycoside hydrolases and carbohydrate esterases [49]. These hydrolytic enzymes break down plant cell walls, and the remaining enzymes either degrade components in fungal cell walls or metabolize storage carbohydrates such as glycogen and trehalose [49].…”

The preparation technology and application of xylo-oligosaccharide as prebiotics in different fields: A review

“…It was found that the main oligosaccharide products of oat xylan treated by endo-xylanase alone were identified as xylobiose and Xylo-pentose, and the content of xylo-tetrasaccharide was low ( 50 , 51 ). Xylobiose and pentose are the main products released by endo-xylanase alone ( 52 ). The authors found that α-L arabinofuranosidase was also able to release arabinose and xylose from oat xylan ( 53 ).…”

Extremophiles, a Nifty Tool to Face Environmental Pollution: From Exploitation of Metabolism to Genome Engineering

“…Acidothermus cellulolyticus 11B, isolated from a hot spring in Yellowstone National Park, produces a tri-functional enzyme that can break down birchwood xylan with high efficiency; in fact, this enzyme has endo-xylanase, arabinofuranosidase, and acetyl-xylan esterase activities [ 141 ].…”