CLONING, CHARACTERIZATION AND ITS POTENTIAL IN PULP BIO BLEACHING BY ALKALI THERMOSTABLE ß-MANNANASE FROM BACILLUS SP. 22

Deepak Kumar, Steffy Angural, Monika Rana, Gurleen Kaur, Neena Puri* and Naveen Gupta*

ABSTRACT

The mannanase gene of Bacillus sp. 22 was cloned and expressed in an Escherichia coli expression system. Recombinant β-mannanase activity was detected on the basis of the clearing of zone around Escherichia coli colonies grown on a congo red dye. Mannanase gene was cloned into the vector pSmart LCKan and expressed in DH10β E. coli. β-Mannanase activities in the culture supernatant were 7Uml-1. β-Mannanase was partially purified using ammonium sulphate precipitation. The molecular mass of the purified mannanase was 38 kDa as estimated by SDS-PAGE. The optimum temperature and pH of recombinant β-mannanase activity was 70°C and 8.8 respectively. Alkali thermostable β-mannanase was applied on kraft pulp to estimate its bio-bleaching potential in industry. β-mannanase from Bacillus sp. 22 shown 11.27% reduction in kappa number.

Keywords: Bacillus, bio-bleaching, ?-mannanase, Kraft pulp, Kappa number.