The importance of chitinases in the physiological and developmental processes of fungi and insects makes themselves and their inhibitors important targets for biological pesticides. A chitinase was isolated from Bombyx mori and purified to electrophoretic homogeneity by ammonium sulfate precipitation and Sephadex G-150 column chromatography. The molecular mass was estimated to be about 88 kDa by SDS-PAGE, while the K(m) was calculated to be 22.3 micromol/L. Moveover, the optimal reaction temperature was 45 degrees C, and the optimum pH was 6.0. The effect of metal ions and organic reagents on chitinase activity was investigated. The activity was enhanced by high concentration of Mn2+, while was strongly inhibited by Cu2+ and SDS. These results provide a basis for screening the chitinase-based biological pesticide.
Animals ; Bombyx ; enzymology ; Chitinases ; isolation & purification ; metabolism ; Enzyme Stability ; Insect Proteins ; isolation & purification ; metabolism ; Temperature

A novel chitinolytic and chitosanolytic bacterium, Sphingomonas sp. CJ-5, has been isolated and characterized. It secretes both chitinase and chitosanase into surrounding medium in response to chitin or chitosan induction. To characterize the enzymes, both chitinase and chitosanase were purified by ammonium sulfate precipitation, Sephadex G-200 gel filtration and DEAE-Sepharose Fast Flow. SDS-PAGE analysis demonstrated molecular masses of chitinase and chitosanase were 230 kDa and 45 kDa respectively. The optimum hydrolysis conditions for chitinase were about pH 7.0 and 36 degrees C, and these for chitosanase were pH 6.5 and 56 degrees C, respectively. Both enzymes were quite stable up to 45 degrees C for one hour at pH 5~8. These results show that CJ-5 may have potential for industrial application particularly in recycling of chitin wastes.
Chitinases ; metabolism ; Enzyme Stability ; Fermentation ; Glycoside Hydrolases ; metabolism ; Hydrogen-Ion Concentration ; Sphingomonas ; enzymology

OBJECTIVE: To examine AMCase mRNA expression levels in nasal mucosa of allergic rhinitis SD rats. METHOD: Thirty SD rats were chosen and randomly divided into the experimental group and the control group. 20 in experimental group and 10 in the control group. AR model rats were established through repeated intraperitoneal shot of ovalbumin (OVA) for 2 weeks and consequently confirmed by local challenge with OVA for 1 week. The control group was treated by the same method with Physiological saline water instead of OVA. After the last excitation allergic rhinitis was diagnosed according to the accumulation score about nasal symptom. The septal mucosa of all rats were used to diagnose pathologically by HE dyeing. AMCase mRNA in nasal mucosa, obtained from the bilateral nasal mucosa in two groups, were used to do reverse transcriptive polymerase chain reaction. Real-time polymerase chain reaction was used to examine AMCase mRNA expression levels. RESULT: (1) The results showed definitely that there were positive expression of AMCase mRNA in normal nasal mucosa. This expression increase significantly during nasal allergy (P < 0.05). (2) The increased expression of AMCase mRNA in allergic rhinitis are related with the nasal symptoms score (r = 0.411, P < 0.05). CONCLUSION Increased expression of AMCase mRNA in nasal mucosa in allergic rhinitis model might play roles in the pathogenesis of AR, and Restrain the enzyme activity could become new treatment targets of allergic rhinitis.
Animals ; Chitinases ; metabolism ; Nasal Mucosa ; metabolism ; Ovalbumin ; RNA, Messenger ; metabolism ; Rats ; Rats, Sprague-Dawley ; Rhinitis, Allergic ; enzymology ; metabolism

The principal component analysis (PCA) was applied to the data processing in training sets, the new principal components were then used as input data for support vector machine model. A prediction model for optimum pH of chitinase was established based on uniform design. When The regularized constant C, epsilon and Gamma were 10, 0.7 and 0.5 respectively, the calculated pHs fitted the reported optimum pHs of chitinase very well and the MAPEs (Mean Absolute Percent Error) was 3.76%. At the same time, the predicted pHs fitted the reported optimum pHs well and the MAE (Mean Absolute Error) was 0.42 pH unit. It was superior in fittings and predictions compared to the model based on back propagation (BP) neural network.
Algorithms ; Animals ; Chitinases ; chemistry ; metabolism ; Humans ; Hydrogen-Ion Concentration ; Models, Biological ; Models, Statistical ; Neural Networks (Computer) ; Principal Component Analysis

The cloned cDNA sequence of rice (Oryza sativa L. Cpslo17) chitinase gene Oschi was cloned, (which was registered in GenBank, the accession number: EU045451) ligated with the expression vector pGEX-4T-1, and transformed into E. coli BL21(DE3). The expression of Oschi was induced by IPTG, and the conditions were optimized. After purification the in vitro activity of Oschi chitinase was analyzed, and the results indicated that it could efficiently degrade chitin.
Chitin ; metabolism ; Chitinases ; biosynthesis ; genetics ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Molecular Sequence Data ; Oryza ; enzymology ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; metabolism

OBJECTIVETo obtain transgenic Pinellia ternata plants resistant to fungus by transfer Chitinase and beta-1,3-Glucanase gene from Trichoderma harzianum.

METHODUsing hygromycin phosphotransferase as the selection marker, the Chitinase gene (ech42), beta-1,3-Glucanase gene (gluc78) and both gene pCAMBIA(ech42 + gluc78) driven by CaMV35S promoter were transferred into P. ternata callus via Agrobacterium-mediated transformation.

RESULTPCR results confirmed that the regenerants were identified to be transgenic lines and the RT-PCR results confirmed that foreign genes construction were transfer to mRNA. Two foreign genes were inherited stably to T5 generation according to PCR results of the lines.

CONCLUSIONThe results showed that chitinase gene ech42 and beta-1, 3-glucanase gene gluc78 respectively or together introducing and co-integrating into P. ternata

Agrobacterium tumefaciens ; genetics ; metabolism ; Chitinases ; genetics ; metabolism ; Fungal Proteins ; genetics ; metabolism ; Gene Expression Regulation, Plant ; Gene Transfer Techniques ; Genetic Vectors ; genetics ; metabolism ; Glucan 1,3-beta-Glucosidase ; genetics ; metabolism ; Pinellia ; genetics ; metabolism ; Transformation, Genetic ; Trichoderma ; enzymology

M1-type macrophages are capable of inducing lysis in various types of cancer cells, but the mechanism of action is unclear. It has been noted that an "unknown protein" produced together with protease by activated macrophages is responsible for this action. Activated M1 macrophages have been recently reported to produce family 18 chitinases, all of which have been named chitotriosidase. Our experiments have demonstrated that family 18 chitinases work together with proteases and can damage various cancer cells both in vitro and in vivo. Thus, in this article, we suggest that the 50-kDa chitotriosidase is the reported "unknown protein". In addition, we discuss how to properly stimulate activated M1 macrophages to produce 50-kDa chitotriosidases and proteases for destroying cancer cells. Because family 19 chitinase has recently been reported to kill cancer cells, we also discuss the possibility of directly using human family 18 chitotriosidase and the humanized plant family 19 chitinase for cancer treatment.
Animals ; Antineoplastic Agents, Alkylating ; pharmacology ; Chitinases ; metabolism ; Cyclophosphamide ; pharmacology ; Hexosaminidases ; metabolism ; Humans ; Immunosuppressive Agents ; pharmacology ; Macrophage Activation ; immunology ; Macrophages ; classification ; enzymology ; immunology ; pathology ; Neoplasms ; immunology ; pathology ; Peptide Hydrolases ; metabolism ; T-Lymphocytes, Regulatory ; metabolism ; Th1 Cells ; metabolism ; Th2 Cells ; metabolism

Peach brown rot, caused by Monilinia fructicola, is one of the most serious peach diseases. A strain belonging to the Actinomycetales, named Streptomyces blastmyceticus JZB130180, was found to have a strong inhibitory effect on M. fructicola in confrontation culture. Following the inoculation of peaches in vitro, it was revealed that the fermentation broth of S. blastmyceticus JZB130180 had a significant inhibitory effect on disease development by M. fructicola. The fermentation broth of S. blastmyceticus JZB130180 had an EC₅₀ (concentration for 50% of maximal effect) of 38.3 µg/mL against M. fructicola, as determined in an indoor toxicity test. Analysis of the physicochemical properties of the fermentation broth revealed that it was tolerant of acid and alkaline conditions, temperature, and ultraviolet radiation. In addition, chitinase, cellulase, and protease were also found to be secreted by the strain. The results of this study suggest that S. blastmyceticus JZB130180 may be used for the biocontrol of peach brown rot.
Ascomycota/pathogenicity* ; Bacterial Proteins/metabolism* ; Cell Wall/metabolism* ; Cellulase/metabolism* ; Chitinases/metabolism* ; Fermentation ; Fruit/microbiology* ; Pest Control, Biological/methods* ; Phylogeny ; Plant Diseases/prevention & control* ; Prunus persica/microbiology* ; Siderophores/metabolism* ; Streptomyces/physiology*