The invention aims at providing a novel chitin enzyme with a high-efficiency degradation rate. The high-activity soluble chitin enzyme is obtained through cloning a gene, which is used for coding thechitin enzyme, in a genome of streptomyces albolongus ATCC (American Type Culture Collection) 27414, constructing a recombinant vector and transferring the recombinant vector into escherichia coli BL21 (DE3) to carry out inducible expression. Through Ni column affinity chromatography, the chitin pure enzyme is purified and obtained; the enzymatic property and hydrolysis mechanism of the chitin pure enzyme are researched; the optimum temperature and optimum pH (potential of Hydrogen) of the enzyme are 55 DEG C and 5.0 respectively; the specific enzyme activity is 66.2U/mg; a main product of degraded chitin is chitobiose, and the chitin enzyme is expected to be applied to the preparation of a chitooligosaccharide, and has potential application value.

Chitin enzyme and application thereof

The invention belongs to the technical field of bioengineering and enzyme engineering, and discloses a polysaccharide hydrolase gene from pyrococcus horikoshii and application. A nucleotide sequence of the polysaccharide hydrolase gene Tk1765 is shown as SEQ ID NO:1. A coding sequence of the polysaccharide hydrolase gene Tk1765 is shown as SEQ ID NO:2. Polysaccharide hydrolase has the efficient cellulose gum and chitose double digest character. According to cellulose gum of the polysaccharide hydrolase, the optimum pH value is 10.0, and the optimum enzyme reaction temperature is 65 DEG C. According to hydrolysis chitose, the optimum pH value is 11.0, and the optimum enzyme reaction temperature is 80 DEG C. The hydrolase is heated for 4 h at the temperature being 100 DEG C, and the activity of the hydrolase can be kept to be 40% or above. A recombinant vector of the hydrolase is constructed and excessively expressed in pichia pastoris, a product of the hydrolase has the function of hydrolyzing maize straw, and the polysaccharide hydrolase and the coding gene thereof can be widely applied to cellulose and chitin degradation.

Polysaccharide hydrolase gene from pyrococcus horikoshii and application

The invention relates to a cellulase gene from extreme saline-alkali resistant aspergilli and application, and belongs to the technical field of bioengineering and enzyme engineering. A nucleotide sequence of the cellulase gene CCHA333 is shown in SEQ ID NO.1, a coding sequence of the cellulase gene CCHA333 is shown in SEQ ID NO.2, and the cellulase gene CCHA333 can be applied to dynamic characteristic identification of an enzyme capable of hydrolyzing sodium carboxymethyl cellulose; the optimal pH value of the cellulase is 6, the optimal enzymatic reaction temperature is 55 DEG C, the pH ranges from 4 to 12, heating is conducted for 2 h at 80 DEG C, and the enzyme activity can be maintained 50 percent or above. Under the environment that many metal ions such as Cu , Co and Na exist, the enzyme activity is obviously improved. Due to the fact that a recombinant vector is built, and a product over expressed in pichia pastoris has the function of efficiently hydrolyzing the sodium carboxymethyl cellulose and maize straw, the cellulase and the coding gene thereof can be widely applied to cellulose degradation.

Wei Yi

Papers

Polysaccharide hydrolase gene from pyrococcus horikoshii and application

Cellulase gene from extreme saline-alkali resistant aspergilli and application