Constitutive chitosanase from Bacillus thuringiensis B-387 and its potential for preparation of antimicrobial chitooligomers.

Autor: Aktuganov GE; Institute of Biology, Ufa Federal Research Center of Russian Academy of Sciences, 69, Prospect Oktyabrya, Ufa, Russia, 450054. gleakt@anrb.ru., Safina VR; Institute of Biology, Ufa Federal Research Center of Russian Academy of Sciences, 69, Prospect Oktyabrya, Ufa, Russia, 450054., Galimzianova NF; Institute of Biology, Ufa Federal Research Center of Russian Academy of Sciences, 69, Prospect Oktyabrya, Ufa, Russia, 450054., Gilvanova EA; Institute of Biology, Ufa Federal Research Center of Russian Academy of Sciences, 69, Prospect Oktyabrya, Ufa, Russia, 450054., Kuzmina LY; Institute of Biology, Ufa Federal Research Center of Russian Academy of Sciences, 69, Prospect Oktyabrya, Ufa, Russia, 450054., Melentiev AI; Institute of Biology, Ufa Federal Research Center of Russian Academy of Sciences, 69, Prospect Oktyabrya, Ufa, Russia, 450054., Baymiev AH; Institute of Biochemistry and Genetics, Ufa Federal Research Center of Russian Academy of Sciences, 71, Prospect Oktyabrya, Ufa, Russia, 450054., Lopatin SA; Institute of Bioengineering of Federal Research Center 'Fundamentals of Biotechnology' of Russian Academy of Sciences, 7, bld. 1, 60 let Oktyabrya prospect, Moscow, Russia, 117312.
Jazyk: angličtina
Zdroj: World journal of microbiology & biotechnology [World J Microbiol Biotechnol] 2022 Jul 22; Vol. 38 (10), pp. 167. Date of Electronic Publication: 2022 Jul 22.
DOI: 10.1007/s11274-022-03359-5
Abstrakt: The article proves the ability of the entomopathogenic strain B. thuringiensis var. dendrolimus B-387 to high the constitutive production (3-12.5 U/mL) of extracellular chitosanase, that was found for the first time. The enzyme was purified in 94-fold by ultrafiltration, affinity sorption and cation-exchange chromatography and characterized biochemically. The molecular mass of the chitosanase determined using SDS-PAGE is 40 kDa. Temperature and pH-optima of the enzyme are 55  ° C and pH 6.5, respectively; the chitosanase was stable under 50-60  ° C and pH 4-10.5. Purified chitosanase most rapidly (V max  ~ 43 µM/mL × min, K M  ~ 0.22 mg/mL, k cat  ~ 4.79 × 10 4  s -1 ) hydrolyzed soluble chitosan of the deacetylation degree (DD) 85% by endo-mode, and did not degrade colloidal chitin, CM-cellulose and some other glucans. The main reaction products of the chitosan enzymolysis included chitobiose, chitotriose and chitotetraose. In addition to small chitooligosaccharides (CHOs), the studied chitosanase also generated low-molecular weight chitosan (LMWC) with average M w in range 14-46 kDa and recovery 14-35%, depending on the enzyme/substrate ratio and incubation temperature. In some cases, the chitosan (DD 85 and 50%) oligomers prepared using crude chitosanase from B. thuringiensis B-387 indicated higher antifungal and antibacterial activities in vitro in comparison with the initial polysaccharides. The data obtained indicate the good prospect of chitosanase B-387 for the production of bioactive CHOs.
(© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)
Databáze: MEDLINE
Externí odkaz: