Biomaterial Database

Purification and characterization of a low molecular weight endo-xylanase from mushroom Termitomyces clypeatus. 2010

Dhananjay Soren, and Mohanlal Jana, and Subhabrata Sengupta, and Anil K Ghosh

Drug Development/Diagnostics & Biotechnology Division, Indian Institute of Chemical Biology, 4, Raja S C Mullick Road, Kolkata 700032, India.

A low molecular weight endo-xylanase (EC 3.2.1.8) was purified from an edible mushroom Termitomyces clypeatus grown in submerged medium with oat spelt xylan. Xylanase was purified to apparent homogeneity by ammonium sulfate fractionation and gel filtration chromatography. Its molecular weight was determined by gel filtration chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis to be 12 kDa. The enzyme was found to be most active at 50 degrees C and pH 5.0, being most stable at pH 6.5. The K(m) for oat spelt xylan was determined to be 10.4 mg/ml. The specificities of the enzyme was observed to be highly specific towards oat spelt xylan and was inhibited by mercuric chloride (HgCl(2)), N-bromosuccinimide, and trans-1,2-diaminocyclohexane-N',N',N',N'-tetraacetic acid strongly. The inhibitory action of N-bromosuccinimide on enzyme confirmed the presence of one tryptophan residue in its substrate-binding site. Amino acid analysis for xylanase showed the presence of high amount of hydrophobic serine, glycine, threonine, and alanine residues. The N-terminal sequencing study for the previously purified and characterized 56 kDa xylanolytic amyloglucosidase reveal the presence of 33.30% identity with glucoamylase chain A from Aspergillus awamori. The N-terminal sequence analysis of the present 12 kDa enzyme showed highest similarity (72.22% identity) towards xylanase from Neurospora crassa.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
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
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
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D013379	Substrate Specificity	A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.	Specificities, Substrate,Specificity, Substrate,Substrate Specificities
D013696	Temperature	The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.	Temperatures
D043364	Endo-1,4-beta Xylanases	Enzymes which catalyze the endohydrolysis of 1,4-beta-D-xylosidic linkages in XYLANS.	Endo-1,4-beta-Xylanase,1,4-beta-D-Xylanohydrolase,Beta-1-4-Endoxylanase,Endo-1,4-Xylanase II,Endo-1,4-beta-Xylanase II,Endoxylanase,Xylanase A,Xylanase B,Xylanase C,Xylanase D,Xylanase J,Xylanase Y,Xylanase Z,beta Xylanase,1,4 beta D Xylanohydrolase,Beta 1 4 Endoxylanase,Endo 1,4 Xylanase II,Endo 1,4 beta Xylanase,Endo 1,4 beta Xylanase II,Endo 1,4 beta Xylanases,Xylanase, beta,Xylanases, Endo-1,4-beta
D055434	Termitomyces	A paleotropical genus of fungi in the family Tricholomataceae. They are obligate symbionts of termites.	Termitomyce