Chitin fungal

Orunsi, N. A., Trinci, A. P. J. Growth of bacteria on chitin, fungal cell walls and fungal biomass, and the effect of extracellular enzymes produced by these cultures on the antifungal activity of amphotericin B. Microbiol 1985,43,17-30. 

Fungal chitin synthases are found as integral proteins of the plasma membrane and in chitosomes a divalent cation, Mg(II), is necessary for enzyme activity but neither primers nor a hpid intermediate are required. The substrate and free GlcNAc activate the allosteric enzyme. UDP, the byproduct of the enzymatic activity, is strongly inhibitory to chitin synthase however, it may be metabohzed readily to UMP by a diphosphatase. 

After this, we demonstrated the ability of wheat anionic POs to bind to the chitin of the cell walls of fungal pathogens. We called these POs "chitin-binding POs" (Maksimov et al., 2003). We were the first to demonstrate the binding of the anionic PO of wheat root to chitin (Maksimov et al., 1994). Besides this, we observed that in some species the activity of POs was increased in the unbound Armoracia rustkana, Lagenaria siceraria) or eluted Pisum sativum, Galega orientalis, Brassica oleraceae) fractions of proteins after interaction with chitin. 

It may be that this fact was associated with the rather complex composition of fungal mycelium, consisting of chitin enclosed in a glucan matrix (Bowman, Free, 2006). Therefore, mature saprophyte mycelium are completely covered by difficult-soluble glucans and the fraction of chitin in the apical cell wall is not sufficient. As such, we supposed that these cationic isoforms bound with another major component of the fungi... 

Khairullin R. M. Yusupova Z. R. Maksimov 1. V. (2000) Protective responses of wheat treated with fungal pathogens 1. Interaction of wheat anionic peroxidases s with chitin, chitosan, and thelyospores of Tilletia caries / / Rus. J of plant physiology. V. 47. N. 1. P. 97-102. 

IV. PARASITISM. Lysis by hydrolytic enzymes excreted by microorganisms is a well-known feature of mycoparasitism. Chitinase and P-l,3 glucanase (laminarase) are particularly important enzymes secreted by fungal mycoparasites capable of degrading the fungal cell wall components, chitin, and P-1,3 glucan (131-134). 

Thus chitin is abunckmt in the sea, in diatom blooms and in the zooplankton, most notably in the shoals of krill and on the land, in invertebrates and in fungi in the soil. Potential industrial sources are wastes from shrimps and crabs, krill, squid, clams and oysters, and fungal fermentations (13). The krUl fishery alone produces 3000 tons per year, currently going to waste. 

The Thomas model has been used for the sorption of heavy metals using fungal biomass, bone char, chitin, and goethite (Kapoor and Viraraghavan, 1998 Lehmann et al.,... 

Chitin is the microfibrillar component of some fungal cell walls and is equivalent to cellulose microfibrils in plants. It is a characteristic feature of the Ascomycetes, Deuteromycetes and Basidiomycetes but is absent in the Phycomycetes, which contain cellulose as their major cell wall constituent. 

Polyoxins are inhibitors of chitin biosynthesis. Chitin is a component of fungal cell walls except in Phycomycete fungi these contain cellulose as their major cell wall constituent, hence polyoxins are inactive against Plasmopara, Pythium and Phytophthora. 

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