11] Two novel lipases from thermophile Bacillus thermocatenulatus: Screening, purification, cloning, overexpression, and properties

Abstract

Publisher Summary This chapter describes the screening process for a thermophilic microbial lipase producer and the purification and characterization of the lipase BTL-1. It deals with the cloning and overexpression of an additional lipase of Bacillus thermocatenulatus , BTL-2. The large-scale production, purification, and characterization of this recombinant lipase BTL-2 are also described. The chapter develops an efficient expression system and simple purification procedure that allows the production of the large amounts of pure enzyme needed for crystallization. Crystallization and X-ray diffraction analysis of the lipase BTL-2 are in progress. Lipase BTL-2 proved to be a stable enzyme, with optimal activity at elevated temperatures and at alkaline pH, which are promising properties for biotechnological applications. The discovery of two different lipases in B. thermocatenulatus prompted to ask why this strain needs two lipolytic enzymes, what their physiological function is, and why only BTL-1 was detected in the culture broth of B. thermocatenulatus on induction with olive oil.