Trends in extracellular serine proteases of bacteria as detergent bioadditive: alternate and environmental friendly tool for detergent industry.

Abstract

Proteases, one of the largest groups of industrial enzymes occupy a major share in detergent industry. To meet the existing demands, proteases with efficient catalytic properties are being explored from bacteria residing in extreme habitats. Alkaline proteases are also considered as promising candidates for industrial sectors due to the activity and stability under alkaline and harsh environment. Therefore, a systematic review on experimental studies of bacterial proteases was conducted with emphasis on purification, characterization, cloning and expression and their suitability as detergent additive. Relevant searches using a combination of filters/keywords were performed in the online databases; PubMed, Science Direct, Scopus and Web of Science. Over thousands of research papers, 71 articles in Scopus, 48 articles in Science Direct, 18 articles in PubMed and 8 articles in Web of Science were selected with regard to bacterial extracellular proteases till date. Selected articles revealed majority of the studies conducted between the years 2015 and 17 and were focused on purification of proteases from bacteria. Among microbes, a total of 41 bacterial genera have been explored with limited studies from extreme habitats. Majority of the studies have reported the involvement of subtilisin-like serine proteases with effective properties for detergent industries. The studies revealed shifting of trend from purification to cloning to genetic engineering to meet the industrial demands. The present systematic review describes the proteases from extremophilic bacteria and use of biotechnological techniques such as site-directed mutagenesis and codon optimization to engineer enzymes with better hot spots in the active sites to meet industrial challenges.