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Updated: Dec 31, 2025
Assays for Validating Histone Acetyltransferase Inhibitors
Published on: August 6, 2020
The Pattern of Acetylation Defines the Priming Activity of Chitosan Tetramers
Sven Basa1, Malathi Nampally1, Talita Honorato1
1University of Münster , Institute for Biology and Biotechnology of Plants , Schlossplatz 8 , 48143 Münster , Germany.
Abstract:
The biological activity of chitosans depends on their degree of polymerization (DP) and degree of acetylation (DA). However, information could also be carried by the pattern of acetylation (PA): the sequence of β-1,4-linked glucosamine (deacetylated/D) and N-acetylglucosamine (acetylated/A) units. To address this hypothesis, we prepared partially acetylated chitosan oligosaccharides from a chitosan polymer (DA = 35%, DPw = 905) using recombinant chitosan hydrolases with distinct substrate and cleavage specificities. The mixtures were separated into fractions DP4-DP12, which were tested for elicitor and priming activities in rice cells. We confirmed that both activities were influenced by DP, but also observed apparent DA-dependent priming activity, with the ADDD+DADD fraction proving remarkably effective. We then compared all four monoacetylated tetramers prepared using different chitin deacetylases and observed significant differences in priming activity. This demonstrates for the first time that PA influences the biological activity of chitosans, which can now be recognized as bona fide information-carrying molecules.
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