| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 34396 | Process Biochemistry | 2015 | 8 Pages |
•Novel family 18 chitinases were identified in T. lanuginosus SSBP.•Presence of a multi-chitinolytic enzyme system was confirmed in this fungus.•Chit1 and Chit2 have both exo- and endochitinase activities.•Chit1 is efficient for biodegradation of chitinous waste.•Chit2 showed antifungal activity against P. verrucosum and A. niger.
The recent sequencing of the Thermomyces lanuginosus SSBP genome by our group has revealed four putative family 18 chitinases. In this study, three novel chitinase genes (chit2, chit3 and chit4) and the previously-reported chit1 gene were cloned from T. lanuginosus SSBP. chit1, encoding a 44.1 kDa protein, and chit2, encoding a 36.6 kDa protein, were successfully expressed in Pichia pastoris. The recombinant Chit1 and Chit2 enzymes exhibited optimum activity at pH 5.0 and pH 4.0, respectively. Chit1 had optimal activity at 50 °C and retained 56% of its activity at 60 °C after 30 min, while Chit2 was optimally active at 40 °C and retained 71% of its activity at 50 °C after 60 min. Both enzymes produced chitobiose as the major product using different substrates. Chit2 displayed antifungal activity against Penicillium verrucosum and Aspergillus niger. These activities could be useful in the environmental degradation of chitinous wastes as well as for biotechnological applications.
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