Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2018 Mar 22;10(4):352.
doi: 10.3390/polym10040352.

Chitin Deacetylases: Structures, Specificities, and Biotech Applications

Laia Grifoll-Romero  1 , Sergi Pascual  2 , Hugo Aragunde  3 , Xevi Biarnés  4 , Antoni Planas  5
Affiliations
Review

Chitin Deacetylases: Structures, Specificities, and Biotech Applications

Laia Grifoll-Romero et al. Polymers (Basel). .

Abstract

Depolymerization and de-N-acetylation of chitin by chitinases and deacetylases generates a series of derivatives including chitosans and chitooligosaccharides (COS), which are involved in molecular recognition events such as modulation of cell signaling and morphogenesis, immune responses, and host-pathogen interactions. Chitosans and COS are also attractive scaffolds for the development of bionanomaterials for drug/gene delivery and tissue engineering applications. Most of the biological activities associated with COS seem to be largely dependent not only on the degree of polymerization but also on the acetylation pattern, which defines the charge density and distribution of GlcNAc and GlcNH₂ moieties in chitosans and COS. Chitin de-N-acetylases (CDAs) catalyze the hydrolysis of the acetamido group in GlcNAc residues of chitin, chitosan, and COS. The deacetylation patterns are diverse, some CDAs being specific for single positions, others showing multiple attack, processivity or random actions. This review summarizes the current knowledge on substrate specificity of bacterial and fungal CDAs, focusing on the structural and molecular aspects of their modes of action. Understanding the structural determinants of specificity will not only contribute to unravelling structure-function relationships, but also to use and engineer CDAs as biocatalysts for the production of tailor-made chitosans and COS for a growing number of applications.

Keywords: carbohydrate esterases; chitin deacetylases; chitooligosaccharides; chitosan; deacetylation pattern; structure; substrate specificity.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Chitin catabolism. GlcNAc: N-acetylglucosamine; GlcN: glucosamine; DA: degree of acetylation. COS: chitooligosaccharides (or chitin oligosaccharides), paCOS: partially acetylated chitooligosaccharides (or chitosan oligosaccharides).
Figure 2
Figure 2
3D structures of CDAs determined by X-ray crystallography. Loops 1 to 6 colored as in Figure 3. The peptidoglycan deacetylase SpPgdA is also included for comparison (see text). In parenthesis, PDB accession codes.
Figure 3
Figure 3
Multiple sequence alignment of the CDA enzymes listed in Table 1. Loops are highlighted with colored boxes according to [69]. Conserved catalytic motifs are labelled MT1-5. The ‘His-His-Asp’ metal binding triad (▼), catalytic base (*), and catalytic acid (◊) are labelled.
Figure 4
Figure 4
Phylogenetic analysis of CDAs from the multiple sequence alignment presented in Figure 3. A bootstrap analysis with 500 replicates was carried out on the trees inferred from the neighbor joining method. The consensus tree is shown with bootstrap values at each node of the tree. Biological functions: cell wall biosynthesis: (a) cell wall, (b) vegetative growth, (c) sporulation; host infection, (d) defense, (e) interaction/infection, (f) autolysis (see text).
Figure 5
Figure 5
Metal-assisted general acid/base mechanism proposed for CE4 deacetylases. Scheme based on the 3D structure of the enzyme·substrate complex VcCDAD39S·DP2 [61]. D39 is the general base and His295 is the general acid.
Figure 6
Figure 6
3D structures of enzyme·substrate complex. (A) VcCDA with DP3 substrate and (B) ArCE with DP2 substrate. Loops 1 to 6 are colored as in Figure 3.
Figure 7
Figure 7
Production routes of all possible chitin and chitosan tetramers using 4 different CDAs to specifically deacetylate or N-acetylate paCOS. A: GlcNAc, D: GlcNH2. Blue arrows, deacetylation reactions, red arrows, N-acetylation reactions in the presence of excess acetate.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Peniche Covas C.A., Argüelles-Monal W., Goycoolea F.M. Chitin and chitosan: Major sources, properties and applications. In: Belgacem M.N., Gandini A., editors. Monomers, Polymers and Composites from Renewable Resources. Volume 1. Elsevier; Amsterdam, The Netherlands: 2008. pp. 517–542.
    1. Karrer P., Hofmann A. Über den enzymatischen Abbau von Chitin und Chitosan I. Helv. Chim. Acta. 1929;12:616–637. doi: 10.1002/hlca.19290120167. - DOI
    1. Rinaudo M. Chitin and chitosan: Properties and applications. Prog. Polym. Sci. 2006;31:603–632. doi: 10.1016/j.progpolymsci.2006.06.001. - DOI
    1. Dutta P.K., Duta J., Tripathi V.S. Chitin and Chitosan: Chemistry, properties and applications. J. Sci. Ind. Res. (India) 2004;63:20–31. doi: 10.1002/chin.200727270. - DOI
    1. Noishiki Y., Takami H., Nishiyama Y., Wada M., Okada S., Kuga S. Alkali-induced conversion of β-chitin to α-chitin. Biomacromolecules. 2003;4:896–899. doi: 10.1021/bm0257513. - DOI - PubMed

LinkOut - more resources

  NODES
twitter 2