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Understanding the Localization of Berylliosis: Interaction of Be²⁺ with Carbohydrates and Related Biomimetic Ligands.

ABSTRACT: The interplay of metal ions with polysaccharides is important for the immune recognition in the lung. Due to the localization of beryllium associated diseases to the lung, it is likely that beryllium carbohydrate complexes play a vital role for the development of berylliosis. Herein, we present a detailed study on the interaction of Be²⁺ ions with fructose and glucose as well as simpler biomimetic ligands, which emulate binding motives of saccharides. Through NMR and IR spectroscopy as well as single-crystal X-ray diffraction, complemented by competition reactions we were able to determine a distinctive trend in the binding affinity of these ligands. This suggests that under physiological conditions beryllium ions are only bound irreversibly in glycoproteins or polysaccharides if a quasi ideal tetrahedral environment and ?⁴ -coordination is provided by the respective biomolecule. Furthermore, Lewis acid induced conversions of the ligands and an extreme increase in the Brønstedt acidity of the present OH-groups imply that upon enclosure of Be²⁺ , alterations may be induced by the metal ion in glycoproteins or polysaccharides. In addition the frequent formation of Be-O-heterocycles indicates that multinuclear beryllium compounds might be the actual trigger of berylliosis. This investigation on beryllium coordination chemistry was supplemented by binding studies of selected biomimetic ligands with Al³⁺ , Zn²⁺ , Mg²⁺ , and Li⁺ , which revealed that none of these beryllium related ions was tetrahedrally coordinated under the give conditions. Therefore, studies on the metabolization of beryllium compounds cannot be performed with other hard cations as a substitute for the hazardous Be²⁺ .

SUBMITTER: Muller M

PROVIDER: S-EPMC6973027 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Understanding the Localization of Berylliosis: Interaction of Be<sup>2+</sup> with Carbohydrates and Related Biomimetic Ligands.

Müller Matthias M Buchner Magnus R MR

Chemistry (Weinheim an der Bergstrasse, Germany) 20191108 71

The interplay of metal ions with polysaccharides is important for the immune recognition in the lung. Due to the localization of beryllium associated diseases to the lung, it is likely that beryllium carbohydrate complexes play a vital role for the development of berylliosis. Herein, we present a detailed study on the interaction of Be<sup>2+</sup> ions with fructose and glucose as well as simpler biomimetic ligands, which emulate binding motives of saccharides. Through NMR and IR spectroscopy a ...[more]

PMID: 31498482

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Dataset Information

Understanding the Localization of Berylliosis: Interaction of Be2+ with Carbohydrates and Related Biomimetic Ligands.

Publications

Understanding the Localization of Berylliosis: Interaction of Be<sup>2+</sup> with Carbohydrates and Related Biomimetic Ligands.

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Understanding the Localization of Berylliosis: Interaction of Be²⁺ with Carbohydrates and Related Biomimetic Ligands.