| Abstrakt: |
Chitinase is an enzyme that breaks down chitin polymer's ß-1, 4-glycosidic bonds. Chitinases having high thermostability makes them suitable to use in different industrial sectors. A 1464-bp chitinase gene, from Paenibacillus sp. Y412MC10 was cloned and produced in E. coli BL21 cells using the pRSETB vector. Gel filtration and ion exchange chromatography were used to purify the recombinant 52 kDa protein. Purified chitinase showed optimum activity at 60°C and pH 5.5 with colloidal chitin breakdown. Enzyme showed stable residual activity within pH range of 4.5-6.5 and >70% thermal stability upto 60°C for 2.5 h. The activity of chitinase increased in the presence of Mn+2, SDS, and methanol. Chitinase has Km and Vmax values of 2.287 mg/ml and 6.784 µM/min, respectively, towards colloidal chitin. The proteinligand docking analysis and molecular dynamic simulation indicated that the interactions of amino acids Asn 204, Glu 277, Leu 278, Asp 312, Glu 314, Gln 372, Tyr 374, Trp 463, Trp 467 from GH18 catalytic domain with (NAG)2 molecule are involved in the enzyme catalytic mechanism. This is the first time a thermostable chitinase from Paenibacillus sp. Y412MC10 has been cloned, expressed heterologously, and purified. [ABSTRACT FROM AUTHOR] |
