Isolation, One-Step Affinity Purification, and Characterization of a Polyextremotolerant Laccase From the Halophilic Bacterium Aquisalibacillus Elongatus and Its Application in the Delignification of Sugar Beet Pulp Publisher Pubmed



Rezaei S¹ ; Shahverdi AR¹ ; Faramarzi MA¹
Source: Bioresource Technology Published:2017

Abstract

The aim of the present work was to study the ability of a halophilic bacterial laccase to efficient delignification in extreme conditions. Here, a highly stable extracellular laccase showing ligninolytic activity from halophilic Aquisalibacillus elongatus is described. The laccase production was strongly influenced by NaCl and CuSO4and under optimal conditions reached 4.8 U mL−1. The monomeric enzyme of 75 kDa was purified by a synthetic affinity column with 68.2% yield and 99.8-fold purification. The enzyme showed some valuable features viz. stability against a wide range of organic solvents, salts, metals, inhibitors, and surfactants and specificity to a wide spectrum of substrates diverse in structure and redox potential. It retained more than 50% of the original activity at 25–75 °C and pH 5.0–10.0. Furthermore, the enzyme was found to be effective in the delignification of sugar beet pulp in an ionic liquid that makes it useful for industrial applications. © 2017 Elsevier Ltd