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Raman Spectroscopic Signature of Ectoine Conformations in Bulk Solution and Crystalline State.

ABSTRACT: Recent crystallographic results revealed conformational changes of zwitterionic ectoine upon hydration. By means of confocal Raman spectroscopy and density functional theory calculations, we present a detailed study of this transformation process as part of a Fermi resonance analysis. The corresponding findings highlight that all resonant couplings are lifted upon exposure to water vapor as a consequence of molecular binding processes. The importance of the involved molecular groups for water binding and conformational changes upon hydration is discussed. Our approach further shows that the underlying rapid process can be reversed by carbon dioxide saturated atmospheres. For the first time, we also confirm that the conformational state of ectoine in aqueous bulk solution coincides with crystalline ectoine in its dihydrate state, thereby highlighting the important role of a few bound water molecules.

SUBMITTER: Solomun T

PROVIDER: S-EPMC7540454 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Raman Spectroscopic Signature of Ectoine Conformations in Bulk Solution and Crystalline State.

Solomun Tihomir T Hahn Marc Benjamin MB Smiatek Jens J

Chemphyschem : a European journal of chemical physics and physical chemistry 20200817 17

Recent crystallographic results revealed conformational changes of zwitterionic ectoine upon hydration. By means of confocal Raman spectroscopy and density functional theory calculations, we present a detailed study of this transformation process as part of a Fermi resonance analysis. The corresponding findings highlight that all resonant couplings are lifted upon exposure to water vapor as a consequence of molecular binding processes. The importance of the involved molecular groups for water bi ...[more]

PMID: 32628316

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