Recombinant β-galactosidases – Past, present and future: A mini review

The present review deals with current developments of novel β-galactosidases derived from recombinant vectors and by protein engineering approaches together with the use of efficient recombinant microbial production systems in order to present the applications of recombinant enzymes as a relevant synthetic tool in biotechnology. The union of specific physical and chemical properties of recombinant proteins with specific recognition of catalytic properties of biomolecules has led to their appearance in myriad novel biotechnological applications. The interest in exploiting recombinant enzymes as biocatalysts is constantly increasing nowadays. The plausible advantages involved with their use include their (1) rigidity and permeability, (2) hydrophobic/hydrophilic character, (3) ease of purification and large-scale production, (4) immediate separation from the reaction mixture after completion of reaction without using any chemicals or heating, (5) regenerability as they impart stability to enzymes by protecting their active sites from deactivation, and (6) recombinant enzymes can be conveniently tailored within utility limits. β-Galactosidase is one of the relatively few enzymes that have been used in large-scale processes to perform lactose hydrolysis and galacto-oligosaccharide production. Thus, the present article gives brief outline of recombinant β-galactosidases obtained from various mesophilic, psychrophilic and thermophilic sources and their potential applications in biotechnology industry.