Genome analysis of Streptomyces sp. UH6 revealed the presence of potential chitinolytic machinery crucial for chitosan production

Abstract

Summary Chitosan and its derivatives have numerous applications in wastewater treatment as bio‐coagulants, flocculants and bio‐adsorbents against both particulate and dissolved pollutants. Chitinolytic bacteria secrete an array of enzymes, which play crucial role in chitin to chitosan conversion. Consequently, there is a growing demand for identification and characterization of novel bacterial isolates with potential implications in chitosan production. We describe genomic features of the new isolate Streptomyces sp. UH6. Analysis of the 6.51 Mb genome revealed the GC content as 71.95% and presence of 6990 coding sequences of which 63% were functionally annotated. Further, we identified two possible chitin‐utilization pathways, which employ secreted enzymes like lytic polysaccharide monooxygenases and family‐18 glycoside hydrolases (GHs). More importantly, the genome has six family‐4 polysaccharide deacetylases with probable role in chitin to chitosan conversion, as well as two chitosanases belonging to GH46 and GH75 families. In addition, the gene clusters, dasABC and ngcEFG coding for transporters, which mediate the uptake of N,N′‐diacetylchitobiose and N‐acetyl‐d‐glucosamine were identified. Several genes responsible for hydrolysis of other polysaccharides and fermentation of sugars were also identified. Taken together, the phylogenetic and genomic analyses suggest that the isolate Streptomyces sp. UH6 secretes potential chitin‐active enzymes responsible for chitin to chitosan conversion.

A novel lytic polysaccharide monooxygenase from enrichment microbiota and its application for shrimp shell powder biodegradation

“…Chitin is the second-most abundant biosynthetic bio-polysaccharide after cellulose and is found in large quantities in shrimp and crab seafood waste ( Zhang et al, 2020 ). Most of these wastes are burned or dumped in coastal areas, causing environmental problems such as water pollution ( Duhsaki et al, 2022 ). Chitin and its derivatives are widely used in biomedicine, cosmetic refinement, food, and agriculture.…”

“…Therefore, industrial enzymes face a major challenge in terms of stability, efficiency, and cost of their application ( Nakagawa et al, 2013 ; Liaqat and Eltem, 2018 ). Microorganisms degrade and/or modify chitin in nature by using a series of synergistically acting chitinolytic enzymes ( Duhsaki et al, 2022 ). Mining novel, highly efficient chitin-degrading enzymes from natural environments will lay a solid foundation for the industrial production of COS.…”

“…This is accomplished by the synergistic action of chitin-degrading enzymes produced by microorganisms ( Wieczorek et al, 2014 ). Many strains and enzymes with chitin-degrading activity have been screened and show remarkable potential in converting chitin into high value-added derivatives and pest control ( Berini et al, 2019 ; Manjeet et al, 2019 ; Peng et al, 2020 ; Duhsaki et al, 2022 ; Wang et al, 2022 ). The synergistic effect of LPMO and chitinase on crystalline chitin has attracted the great attention of researchers at home and abroad.…”

The assessment of microbial ecology: a special emphasis on the Indian scenario

“…Furthermore, the issue also has articles from scientists, utilizing genomic information for deciphering novel microbial resources. Duhsaki et al (2021) identified chitinolytic enzymes from the genome analysis of Streptomyces sp. UH6 for chitosan production, therefore having industrial applications.…”

“…Duhsaki et al . (2021) identified chitinolytic enzymes from the genome analysis of Streptomyces sp. UH6 for chitosan production, therefore having industrial applications.…”