Chitinase

About: Chitinase is a research topic. Over the lifetime, 4690 publications have been published within this topic receiving 161786 citations. The topic is also known as: 1,4-beta-poly-N-acetylglucosaminidase & poly-beta-glucosaminidase.

A technique for detection of chitinase, beta-1,3-glucanase, and protein patterns after a single separation using polyacrylamide gel electrophoresis or isoelectrofocusing

Abstract: A procedure to detect chitinase and beta-1,3-glucanase isozymes and protein patterns after a single separation using native polyacrylamide gel electrophoresis (PAGE) or isoelectrofocusing (IEF) is described. After electrophoresis or isoelectrofocusing, an overlay gel containing glycol chitin as substrate for chitinase was incubated in close contact with the resolving gel. Chitinase isozymes were revealed by UV illumination after staining the overlay gel with fluorescent brightener 28. The resolving gel was then incubated with laminarin, and beta-1,3-glucanase isozymes were detected by using 2,3,5-triphenyltetrazolium chloride. The resolving gel with beta-1,3-glucanase bands was stained with Coomassie Brilliant Blue R 250 to reveal protein patterns. The isozymes were quantified by using native PAGE, and their pIs were estimated by IEF

Insect resistance of transgenic tobacco expressing an insect chitinase gene

Abstract: Chitinase expression in the insect gut normally occurs only during moulting, where the chitin of the peritrophic membrane is presumably degraded. Thus, insects feeding on plants that constitutively express an insect chitinase gene might be adversely affected, owing to an inappropriately timed exposure to chitinase. This hypothesis was tested by introducing a cDNA encoding a tobacco hornworm (Manduca sexta) chitinase (EC 3.2.1.14) into tobacco via Agrobacterium tumefaciens-mediated transformation. A truncated but enzymatically active chitinase was present in plants expressing the gene. Segregating progeny of high-expressing plants were compared for their ability to support growth of tobacco budworm (Heliothis virescens) larvae and for feeding damage. Both parameters were significantly reduced when budworms fed on transgenic tobacco plants expressing high levels of the chitinase gene. In contrast, hornworm larvae showed no significant growth reduction when fed on the chitinase-expressing transgenics. However, both budworm and hornworm larvae, when fed on chitinase-expressing transgenic plants coated with sublethal concentrations of a Bacillus thuringiensis toxin, were significantly stunted relative to larvae fed on toxin-treated non-transgenic controls. Foliar damage was also reduced. Plants expressing an insect chitinase gene may have agronomic potential for insect control.

Fungal and plant gene expression during synchronized infection of tomato leaves by Botrytis cinerea

Abstract: An inoculation procedure was developed to obtain efficient and synchronous infection on detached tomato leaves by Botrytis cinerea. In spray-inoculated leaves incubated at 20 °C, the infection process consisted of three phases: the formation of primary necrotic lesions (until 20 hpi), a quiescent phase (20-72 hpi), and the expansion of a proportion of the primary lesions (from 72 hpi onwards), resulting in full tissue maceration. At 4 °C, the infection progressed slowly but steadily without inducing necrotic responses in the host. The actin and β-tubulin genes of B. cinerea were cloned, characterized and used as probes on blots containing RNAs from leaves at various stages of the infection. The genes displayed a similar expression pattern throughout the infection and the hybridization signal reflected the amount of fungal biomass. The actin mRNA accumulated to higher levels than the β-tubulin mRNA. Tomato PR protein mRNAs (chitinase, β-1,3-glucanase and PR-1) were induced during the infection, albeit with different kinetics and to different levels. At 20 °C, β-1,3-glucanase and PR-1 mRNAs were induced more rapidly than chitinase mRNAs. At 4 °C, mRNAs encoding extracellular β-1,3-glucanase and intracellular, as well as extracellular chitinase were hardly induced.