Chitinase induction

Immediately following chitin amendment, replicate sediment containers were held at 4-5° C. After 30 days, at this low temperature, there also was chitinase induction which could conceivably occur during winter conditions. It must be noted that although the sediments were initially reducing, the experiment was conducted with flowing sea water and only the surface one cm oxidized layer was analyzed in the present work. 

Chitinase induction in estuarine sediments was documented. Although the polymer chitin (poly-N-acetyl-D-glucosamine) is the major organic component of all arthropod exoskeletons and is prolific in the diatoms, there has been no demonstration of the chit in-induced hydrolytic enzymes (chitinases) responsible for the extracellular digestion of these ubiquitous chitins. Blue crab (Callinectes sapidus) exoskeleton was dosed into compacted anaerobic muds. Subsequent incubation for 30 d under aerobic ambient seawater conditions (28° C 12-15 ppt salinity) resulted in significant increases of chitinase in amended sediment as compared to controls which had... 

Metraux, J.P. Boiler, Th. (1986). Local and systemic induction of chitinase in cucumber plants in response to viral, bacterial and fungal infections. Physiological and Molecular Plant Pathology, 28, 161-9. 

Tuzun, S., Rao, N., Voegli, U., Schardl, C. Kuc, J. (1989). Induced systemic resistance to blue mold early induction and accumulation of P-l,3-glucanases, chitinases, and other pathogenesis-related proteins (b-proteins) in immunized tobacco. Phytopathology 79, 979-83. 

Qiu, J., Hallmann, J., Kokalis-Burelle, N., Weaver, D.B., Rodriguez-Kabana, R., Tuzan, S. Activity and Differential Induction of Chitinase Isozymes in Soybean Cultivars Resistant or Susceptible to Root-knot... 

Microbial polysaccharides have been shown to stress plant cells, resulting in elicitation (induction) and increased metabolite synthesis. Induction of various enzymes has been reported. Chitosan successfully elicited chitinase production in carrot (Daucus carota) cell cultures and elicitation of desired food ingredients and processing aids via chitosan has been attempted. 

Derckel, J.P., Audran, J.C., Haye, B., Lambert, B. and Legendre, L. (1998) Characterization, induction by wounding and salicylic acid and activity against Botrytis cinerea of chitinases and beta-l,3-glucanases of ripening grape berries, Physiol. Plantarum, 104, 56-64. 

Yu, L.X., Djebrouni, M., Chamberland, H., Lafontaine, J.G. and Tabaeizadeh, Z. (1998) Chitinase Differential induction of gene expression and enzyme activity by drought stress in the wild (Lycopersicon chilense Dun.) and cultivated (L. esculentum Mill.) tomatoes, J. Plant Physiol., 153, 745-753. 

In this review, we examine the induced chemical defenses of P. abies, defenses whose levels increase following herbivore or pathogen attack. Induced defenses have attracted much attention in recent years because of their widespread occurrence in plants and their usefulness as subjects for study. Here, we cover the induction of several different classes of induced defenses in P. abies, including terpene-containing resins, phenolic compounds, and chitinases. Our focus is not only on their defensive roles, but also on how the levels of these compounds may be manipulated by biochemical and molecular methods while minimizing other phenotypic changes. Manipulation of defense compoimds in intact plants is a valuable approach to assessing their value to the plant. 

In conifers, chitinases have been reported to be induced by pathogen attack and wounding in both P. abies and Pinus Induction occurs at the level... 

Based on our current knowledge, the chemistry of induced defenses in P. abies and other woody plants is not materially different from that of herbaceous plants. Terpenes, phenolics, and chitinases are all common metabolites in herbs, and in many cases are inducible upon herbivory or pathogen infection. However, the presence of inducible terpene resins is a special feature of conifers. In the rest of the plant kingdom, mixtures of terpenes accumulate in resin ducts, cavities or glandular hairs of many taxa, but are usually not reported to be inducible. Moreover, the long induction time of conifer resin also sets it apart from other induced defenses. 

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