Characterization of the First Fungal Glycosyl Hydrolase Family 19 Chitinase (NbchiA) from Nosema bombycis (Nb)
MetadataShow full item record
© 2015 The Author(s) Journal of Eukaryotic Microbiology. © 2015 International Society of Protistologists. Chitinases (EC 18.104.22.168), as one kind of glycosyl hydrolase, hydrolyze the ß-(1,4) linkages of chitin. According to the sequence similarity, chitinases can be divided into glycoside hydrolase family 18 and family 19. Here, a chitinase from Nosema bombycis (NbchiA) was cloned and purified by metal affinity chromatography and molecular exclusion chromatography. Sequence analysis indicated that NbchiA belongs to glycoside hydrolase family 19 class IV chitinase. The optimal pH and temperature of NbchiA are 7.0 and 40 C, respectively. This purified chitinase showed high activity toward soluble substrates such as ethylene glycol chitin and soluble chitosan. The degradation of chitin oligosaccharides (GlcNAc)2-5 detected by high-performance liquid chromatography showed that NbchiA hydrolyzed mainly the second glycosidic linkage from the reducing end of (GlcNAc)3-5. On the basis of structure-based multiple-sequence alignment, Glu51 and Glu60 are believed to be the key catalytic residues. The site-directed mutation analysis revealed that the enzymatic activity was decreased upon mutation of Glu60, whereas mutation of Glu51 totally abolished the enzymatic activity. This is the first report of a GH19 chitinase in fungi and in Microsporidia.
Showing items related by title, author, creator and subject.
Molecular dynamics simulation study and hybrid pharmacophore model development in human LTA4H inhibitor designThangapandian, S.; John, S.; Arooj, Mahreen; Lee, K. (2012)Human leukotriene A4 hydrolase (hLTA4H) is a bi-functional enzyme catalyzes the hydrolase and aminopeptidase functions upon the fatty acid and peptide substrates, respectively, utilizing the same but overlapping binding ...
Molecular Modeling Study for Inhibition Mechanism of Human Chymase and Its Application in Inhibitor DesignArooj, Mahreen; Kim, Songmi; Sakkiah, Sugunadevi; Ping Cao, Guang; Lee, Yuno; Woo Lee, Keun (2013)Human chymase catalyzes the hydrolysis of peptide bonds. Three chymase inhibitors with very similar chemical structures but highly different inhibitory profiles towards the hydrolase function of chymase were selected with ...
HAD hydrolase function unveiled by substrate screening: Enzymatic characterization of Arabidopsis thaliana subclass I phosphosugar phosphatase AtSgppCaparrós-Martín, Jose; McCarthy-Suárez, I.; Culiáñez-Macià, F. (2013)This work presents the isolation and the biochemical characterization of the Arabidopsis thaliana gene AtSgpp. This gene shows homology with the Arabidopsis low molecular weight phosphatases AtGpp1 and AtGpp2 and the yeast ...