Department of Biology - Chemistry and Advanced Environmental Research Laboratories, Faculty of Chemistry, Biology, Geography, West University of Timisoara, Timisoara, Romania.
SINTEF, Department of Biotechnology, Trondheim, Norway.
J Mol Graph Model. 2019 May;88:41-48. doi: 10.1016/j.jmgm.2019.01.002. Epub 2019 Jan 9.
Chitin deacetylases are a group of enzymes catalysing the conversion of chitin to chitosan. Obtaining chitosan with established deacetylation degree and pattern is important for biomedical and biotechnological applications. Understandings of the structural properties of chitin deacetylases and the specificity of their interactions with chitin may conduct to the control of the pattern of deacetylation of chitosan. Our study is focused on the characterization and comparison of the structural and physicochemical properties of chitin deacetylases from fungi and marine bacteria. Despite the low sequences identity for the investigated chitin deacetylases, there are amino acids belonging to their active sites that are strongly conserved. Moreover, they reveal an increased structural similarity of their catalytic domains, reflecting the common biological function of these enzymes. The studied enzymes present dissimilar local physicochemical properties of their catalytic cavities that could be responsible of their distinct deacetylation patterns. Molecular docking studies reflect that deacetylation efficiency is also distinct for the chitin and partially deacetylated chitin oligomers and that N-acetylglucosamine units and some partially deacetylated chitin oligomers could have inhibitory effect against chitin deacetylases belonging to fungi and marine bacteria.
几丁质脱乙酰酶是一组催化几丁质转化为壳聚糖的酶。获得具有既定脱乙酰度和模式的壳聚糖对于生物医学和生物技术应用非常重要。了解几丁质脱乙酰酶的结构特性及其与几丁质相互作用的特异性，可能有助于控制壳聚糖的脱乙酰模式。我们的研究集中于真菌和海洋细菌来源的几丁质脱乙酰酶的结构和理化性质的表征和比较。尽管研究的几丁质脱乙酰酶序列同一性较低，但它们的活性位点仍存在强烈保守的氨基酸。此外，它们的催化结构域具有更高的结构相似性，反映了这些酶的共同生物学功能。研究的酶具有不同的催化腔局部理化性质，这可能是它们不同脱乙酰模式的原因。分子对接研究反映出，脱乙酰效率对于几丁质和部分脱乙酰壳聚糖寡糖也是不同的，并且 N-乙酰葡萄糖胺单元和一些部分脱乙酰壳聚糖寡糖可能对属于真菌和海洋细菌的几丁质脱乙酰酶具有抑制作用。
