Bioconversion of chitin into chitin oligosaccharides using a novel chitinase with high chitin-binding capacity

Qiong Zhao; Liqiang Fan; Chen Deng; Chunyu Ma; Chunyue Zhang; Liming Zhao

doi:10.1016/j.ijbiomac.2023.125241

Bioconversion of chitin into chitin oligosaccharides using a novel chitinase with high chitin-binding capacity

Int J Biol Macromol. 2023 Jul 31:244:125241. doi: 10.1016/j.ijbiomac.2023.125241. Epub 2023 Jun 9.

Authors

Qiong Zhao¹, Liqiang Fan¹, Chen Deng¹, Chunyu Ma¹, Chunyue Zhang², Liming Zhao³

Affiliations

¹ State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai 200237, China.
² State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China. Electronic address: chunyue.zhang@ecust.edu.cn.
³ State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; Shanghai Collaborative Innovation Center for Biomanufacturing Technology (SCICBT), Shanghai 200237, China; Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, School of Pharmacy, East China University of Science and Technology, 130 Mei Long Road, Shanghai 200237, China. Electronic address: zhaoliming@ecust.edu.cn.

PMID: 37301336
DOI: 10.1016/j.ijbiomac.2023.125241

Abstract

Chitin is the second largest renewable biomass resource in nature, it can be enzymatically degraded into high-value chitin oligosaccharides (CHOSs) by chitinases. In this study, a chitinase (ChiC8-1) was purified and biochemically characterized, its structure was analyzed by molecular modeling. ChiC8-1 had a molecular mass of approximately 96 kDa, exhibited its optimal activity at pH 6.0 and 50 °C. The K_m and V_max values of ChiC8-1 towards colloidal chitin were 10.17 mgmL^-1 and 13.32 U/mg, respectively. Notably, ChiC8-1 showed high chitin-binding capacity, which may be related to the two chitin binding domains in the N-terminal. Based on the unique properties of ChiC8-1, a modified affinity chromatography method, which combines protein purification with chitin hydrolysis process, was developed to purify ChiC8-1 while hydrolyzing chitin. In this way, 9.36 ± 0.18 g CHOSs powder was directly obtained by hydrolyzing 10 g colloidal chitin with crude enzyme solution. The CHOSs were composed of 14.77-2.83 % GlcNAc and 85.23-97.17 % (GlcNAc)₂ at different enzyme-substrate ratio. This process simplifies the tedious purification and separation steps, and may enable its potential application in the field of green production of chitin oligosaccharides.

Keywords: Biodegradation; Chitin oligosaccharides; Chitinase; Molecular simulation; Purification.

MeSH terms

Chitin* / chemistry
Chitinases* / chemistry
Oligosaccharides
Substrate Specificity

Substances

Chitin
Chitinases
Oligosaccharides