Glucans, elicitors

However, these elegant glycosylated nanostructures displayed only weak biological activity relative to their native glucan elicitor counterparts. Nevertheless, such glycoclusters provided unique environments for host-guest chemistry of amphi-pathic molecules owing to their lipophilic core surrounded by a hydrophilic periphery. 

Secondly, the deacetylated form of chitin, chitosan, does not induce phytoalexin formation in the rice system but is active in other plant culture systems [99]. Glucan elicitors induce phytoalexins in legumes (soybean, chickpea, bean, alfalfa, pea) and solanaceous sp. (potato, sweet pepper) [100]. However, anthraquinone biosynthesis was stimulated in Morinda citrifolia by both chitin and chitosan. The degree of acetylation was found to be important in inducing defense responses. During the first few days of incubation after adding elicitor,... 

Treatment of cell suspension cultures of T. rugosum with a yeast glucan elicitor induced the production of tyrosine decarboxylase in the late exponential and early stationary growth phases of the cells. Tyrosine decarboxylase has been suggested as the key enzyme between primary and secondary metabolism in the biosynthesis of norlaudanosoline-derived alkaloids, and a good correlation between induced tyrosine decarboxylase activity and berberine biosynthesis has been established [163]. 

Cline and Albershelm (35) suggested that the primary event in activating the biochemical processes leading to increased concentrations of phytoalexins in plants is the binding of ellcltors to receptors in the plasma membrane. Initial evidence for this was reported by Yoshlkawa et al. 36) when they found that soybean membrane preparations bound HC-laminaran (a 8-1,3-glucan elicitor from Phytophthora spp.). The receptor, while not yet characterized, appears to be a protein or glycoprotein. 

Glucan Elicitors of Phytoalexin Production. Phytoalexins are post-infection toxins formed de novo by the host. 

Klarzynski O, Plesse B, Joubert JM, Yvin JC, Kopp M, Kloareg B, Fritig B (2000) Linear beta-1, 3-glucans are elicitors of defense responses in tobacco. Plant Physiol 124 1027-1038 Klebanoff SJ (1980) Oxygen metabolism and the toxic properties of phagocytes. Ann Intern Med 93 480-489... 

The phytoalexin elicitor (PE) family of /1-D-glucans (Fig. 5) was selected as a target because these oligosaccharides had been synthesized previously in solution48,49 and on the solid support.50,51 It was our intention to investigate not only the application of glycosyl phosphates to automated solid-phase synthesis, but also to compare our method to the previously described reports of PE syntheses. 

Glucan [antifungal-degrades fungal cell wall releases oligosaccharide elicitor]... 

Smith C, Bolwell GP (1997) Purification of an elicitor-induced glucan synthase (callose synthase) from suspension cultures of French bean [Phaseolus vulgaris L.) purification and... 

Among the polysaccharide elicitors are 3,6-3-glucans from Phytophthora megasperma (84, 85) and yeast cell walls (59) and the algal glucan, laminarin (84)., which have structures comparable to those described for the wilt-inducing P. cinnamomi,... 

A glucan from yeast extract containing 3-, 6-, and 3,6-linked glucosyl residues was shown to elicit formation of glyceollin in soybeans Glycine max, Fabaceae). The yeast-derived elicitor stimulates accumulation of this isoflavone when as little as 15 ng of the elicitor is applied to soybean cotyledons (Hahn and Albersheim, 1978). 

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