Purification and characterization of a cold-adapted lipase from Oceanobacillus strain PT-11.

Tian Jiewei,Lei Zuchao,Qiu Peng,Tian Yongqiang,Wang Lei,Andrew C Marr

doi:10.1371/journal.pone.0101343

Abstract

We isolated a moderately halophilic lipase-producing bacterium from the saline soil. Based on the morphological, physiological, chemotaxonomic and phylogenetic analysis, the isolate PT-11 was postulated to be a novel species identified as Oceanobacillus rekensis PT-11. The lipase was purified 2.50-fold by Q-Sepharose FF and SP-Sepharose FF chromatography and its molecular mass was estimated to be 23.5 kDa by SDS-PAGE. It was highly active over the broad temperature ranging from 10 to 35°C and showed up to 80% of the maximum activity at 10°C indicating the lipase to be a typical cold-adapted enzyme. The enzyme activity was slightly enhanced by Na+, Li+ and K+. Incubation with detergents, such as Tween-20 and Tween-80, slightly inhibited the enzyme activity; while Triton X-100decreased the enzyme activity. The enzyme was fairly stable in the presence of long-chain alcohols but was highly denatured in hydrophilic solvents such as acetone or short-chain alcohols (C1–C3).

Highlights

Extremophilic organisms play a surprisingly important role in the scientific community because of the molecular adaptation they underwent during evolution and for their biotechnological potential [1,2,3]
Saline soil in Shache is the typical type of saline soil in Xinjiang, where the main ions are chlorine and sulphate
Tests for the utilization of different carbon sources were performed by the BIOLOG-GNIII system and the result was shown in table S1

Summary

Introduction

Extremophilic organisms play a surprisingly important role in the scientific community because of the molecular adaptation they underwent during evolution and for their biotechnological potential [1,2,3]. The extremophiles face hyperhaline, organic, hypertonic or extreme temperature enviroments; the extremophiles have to change properties of their macromolecules in order to maintain normal physiological activity in extreme conditions. Many of them have wide substrate tolerance, high stereospecificity toward chemicals, and high stability in organic solvents [6,7]. They are very interesting biocatalysts for industrial purposes such as detergency, flavour production, paper recycling, chemical synthesis, resolution of racemic mixtures [8,9,10]

Methods

Results

Conclusion