Heterologous expression and characterization of thermostable chitinase and β-N-acetylhexosaminidase from Caldicellulosiruptor acetigenus and their synergistic action on the bioconversion of chitin into N-acetyl-d-glucosamine.

Autor: Qin X; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China., Xin Y; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China., Su X; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China., Wang X; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China., Zhang J; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China., Tu T; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China., Wang Y; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China., Yao B; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China., Huang H; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China. Electronic address: huanghuoqing@caas.cn., Luo H; State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing 100193, China. Electronic address: luohuiying@caas.cn.
Jazyk: angličtina
Zdroj: International journal of biological macromolecules [Int J Biol Macromol] 2021 Dec 01; Vol. 192, pp. 250-257. Date of Electronic Publication: 2021 Oct 07.
DOI: 10.1016/j.ijbiomac.2021.09.204
Abstrakt: The bioconversion of chitin into N-acetyl-d-glucosamine (GlcNAc) using chitinolytic enzymes is one of the important avenues for chitin valorization. However, industrial applications of chitinolytic enzymes have been limited by their poor thermostability. Therefore, it is necessary to discover thermostable chitinolytic enzymes for GlcNAc production from chitin. In this study, two chitinolytic enzyme-encoding genes CaChiT and CaHex from Caldicellulosiruptor acetigenus were identified and heterologously expressed in Escherichia coli. The purified recombinant CaChiT and CaHex showed optimal activities at 70 °C and 90 °C respectively, and exhibited good thermostability over a range of temperature below 70 °C and broad pH stability at pH range of 3.0-8.0. CaChiT and CaHex were active on colloidal chitin, pNP-(GlcNAc) 2 , pNP-(GlcNAc) 3 , and pNP-GlcNAc, pNP-(GlcNAc) 2 , pNP-(GlcNAc) 3 , pNP-Glc respectively. Besides, the chitin oligosaccharides and colloidal chitin hydrolysis profiles revealed that CaChiT degraded chitin chains through exo-mode of action. Furthermore, CaChiT and CaHex exhibited a synergistic effect in the degradation of colloidal chitin, reaching 0.60 mg/mL of GlcNAc production after 1 h incubation. These results suggested that a combination of CaChiT and CaHex have great potential for industrial applications in the enzymatic production of GlcNAc from chitin-containing biowastes.
(Copyright © 2021. Published by Elsevier B.V.)
Databáze: MEDLINE
Externí odkaz: