Crab-Eating Monkey Acidic Chitinase (CHIA) Efficiently Degrades Chitin and Chitosan under Acidic and High-Temperature Conditions

Abstract

Chitooligosaccharides, the degradation products of chitin and chitosan, possess anti-bacterial, anti-tumor, and anti-inflammatory activities. The enzymatic production of chitooligosaccharides may increase the interest in their potential biomedical or agricultural usability in terms of the safety and simplicity of the manufacturing process. Crab-eating monkey acidic chitinase (CHIA) is an enzyme with robust activity in various environments. Here, we report the efficient degradation of chitin and chitosan by monkey CHIA under acidic and high-temperature conditions. Monkey CHIA hydrolyzed α-chitin at 50 °C, producing N-acetyl-D-glucosamine (GlcNAc) dimers more efficiently than at 37 °C. Moreover, the degradation rate increased with a longer incubation time (up to 72 h) without the inactivation of the enzyme. Five substrates (α-chitin, colloidal chitin, P-chitin, block-type, and random-type chitosan substrates) were exposed to monkey CHIS at pH 2.0 or pH 5.0 at 50 °C. P-chitin and random-type chitosan appeared to be the best sources of GlcNAc dimers and broad-scale chitooligosaccharides, respectively. In addition, the pattern of the products from the block-type chitosan was different between pH conditions (pH 2.0 and pH 5.0). Thus, monkey CHIA can degrade chitin and chitosan efficiently without inactivation under high-temperature or low pH conditions. Our results show that certain chitooligosaccharides are enriched by using different substrates under different conditions. Therefore, the reaction conditions can be adjusted to obtain desired oligomers. Crab-eating monkey CHIA can potentially become an efficient tool in producing chitooligosaccharide sets for agricultural and biomedical purposes.

Chitinase-Assisted Bioconversion of Chitinous Waste for Development of Value-Added Chito-Oligosaccharides Products

“…After the treatment of chitosan with porcine ChiA, the main products are similar to (GlcNAc) 3 or hetero-chitotrimers such as GlcN-GlcNAc-GlcNAc and GlcNAc-GlcN-GlcNAc [85]. In a report by Uehara, et al [90], monkey ChiA produced the highest levels of (GlcNAc) 2 from chitin, followed by random-type chitosan, α-chitin, colloidal chitin, and block-type chitosan (Figure 2A,B). For chitosan substrates, the pattern of the produced COSs is different between the chitosan types (Figure 2B).…”

“…Those two chitinases include chitotriosidase (ChiT1) and acidic chitinase (ChiA or AMCase), which belong to the GH18. The acidic chitinases which exhibit chitinolytic activity and degrade chitosan to produce COS under stomach conditions are found in porcine [84,85], mouse [86,87], chicken (Gallus gallus domesticus) [88], marmoset (Callithrix jacchus) [89], and crab-eating monkey (Macaca fascicularis) [90,91]. AMCase is predominantly found in pig stomach tissue.…”

Evolutionary insights into sequence modifications governing chitin recognition and chitinase inactivity in YKL-40 (HC-gp39, CHI3L1)

“…Mature YKL-40 was derived from human lung tissue complementary DNA (cDNA) by PCR using KOD-Plus-DNA polymerase (Toyobo) and oligonucleotide primers (Eurofins Genomics) anchored with the restriction sites for BamHI and XhoI as described previously ( Table S2 ) ( 60 ). We used BamHI and Xhol to cut the amplified cDNA and cloned it into the same site of pET22b/pre-Protein A-monkey AMCase-V5-His ( 61 , 62 ). The complete sequence of the obtained plasmid DNA (pET22b/YKL-40/V5-His) was identified by sequencing (Eurofins Genomics).…”