Mining and characterization of two novel chitinases from Hirsutella sinensis using an efficient transcriptome-mining approach.

摘要: Abstract Two novel family 18 chitinases, chiA and chiH , were identified cloned from the transcriptome of H. sinensis based on sequence data. The recombinant chitinases overexpressed in Escherichia coli BL21, subsequently purified functionally characterized. optimal temperature pH for 55 °C 5.0, respectively, those 50 °C respectively. highest enzyme activities 11.5 U/mg 8.1 obtained chiH, when colloidal chitin was used as substrate with Ba 2+ . exhibited higher V max 1.94 μmol/μg/h k cat 1.443 S −1 than 1.63 μmol/μg/h 1.175 S both efficient towards compared other typical chitinases. Substrate specificity gene expression analyses indicated that preferred substrates containing N -acetyl groups, such glycol chitin, while no activity detected toward laminarin, cellobiose, carboxymethyl cellulose starch. work presented here would aid understanding performance future studies infection mechanism