Biomaterial Database

Purification of a heat-stable chitin deacetylase from Aspergillus nidulans and its role in cell wall degradation. 1995

C Alfonso, and O M Nuero, and F Santamaría, and F Reyes

Departamento de Microbiología Aplicada, Centro de Investigaciones Biológicas (C.S.I.C.), Madrid, Spain.

An extracellular chitin deacetylase activity has been purified to homogeneity from autolyzed cultures of Aspergillus nidulans. This enzyme is an acidic glycoprotein with a pI of 2.75 and a 28% (wt/wt) carbohydrate content. The apparent M(r) of the enzyme estimated by SDS/PAGE and Superose 12 (f.p.l.c.) was around 27,000. The enzyme had an optimum pH at 7.0 and was stable in the pH range 4.0-7.5. Its optimum temperature of reaction was 50 degrees C, and it was stable from 30 degrees to 100 degrees C after 1 h of preincubation. The enzyme hydrolyzed glycol chitin and oligomers of N-acetylglucosamine and to a lesser extent chitin, colloidal chitin, carboxymethylchitin, and an alpha-1-->3, 1-->6-N-acetylgalactosamine-galactan among other substances with amido groups, but the enzyme did not hydrolyze peptide bonds. The role of this enzyme could be deacetylation of chitin oligosaccharides during autolysis, after action of endochitinase on cell walls.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D002473	Cell Wall	The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.	Cell Walls,Wall, Cell,Walls, Cell
D002686	Chitin	A linear polysaccharide of beta-1->4 linked units of ACETYLGLUCOSAMINE. It is the second most abundant biopolymer on earth, found especially in INSECTS and FUNGI. When deacetylated it is called CHITOSAN.
D004795	Enzyme Stability	The extent to which an enzyme retains its structural conformation or its activity when subjected to storage, isolation, and purification or various other physical or chemical manipulations, including proteolytic enzymes and heat.	Enzyme Stabilities,Stabilities, Enzyme,Stability, Enzyme
D006358	Hot Temperature	Presence of warmth or heat or a temperature notably higher than an accustomed norm.	Heat,Hot Temperatures,Temperature, Hot,Temperatures, Hot
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000581	Amidohydrolases	Any member of the class of enzymes that catalyze the cleavage of amide bonds and result in the addition of water to the resulting molecules.	Amidases,Amidohydrolase
D001233	Aspergillus nidulans	A species of imperfect fungi from which the antibiotic nidulin is obtained. Its teleomorph is Emericella nidulans.	Aspergillus nidulellus,Emericella nidulans
D001329	Autolysis	The spontaneous disintegration of tissues or cells by the action of their own autogenous enzymes.	Autolyses