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. 2023 Apr;55(4):443-450.
doi: 10.1007/s00726-023-03238-9. Epub 2023 Jan 24.

Analysis of protonation equilibria of some alanyl dipeptides in water and aqueous ethanol mixtures

Tuğçe Deniz Karaca  1 , Alev Doğan  2
Affiliations

Analysis of protonation equilibria of some alanyl dipeptides in water and aqueous ethanol mixtures

Tuğçe Deniz Karaca et al. Amino Acids. 2023 Apr.

Abstract

The protonation constants are one of the most fundamental properties of biological molecules. The determination of the constants of the dipeptide is interesting and necessary for a full understanding of its activities in biological process. In this study, the protonation constants of some aliphatic alanine dipeptides (alanyl-alanine, alanyl-phenylalanine, alanyl-valine, alanyl-leucine, and alanyl-methionine) were studied in water and ethanol-water mixtures (20%ethanol-80%water;40%ethanol-60%water;60%ethanol-40%water, (v/v)) at 25 ± 0.1 °C under nitrogen atmosphere and ionic strength at 0.10 mol L-1 by potentiometry. The constants of the systems were calculated using Best computer program. The effects of the different amino acids bound to the alanine on the acidity of the alanyl dipeptides were investigated. The constants were influenced by changes in solvent composition and their variations were discussed in terms of solvent and structural properties.

Keywords: Alanyl dipeptides; Ethanol–water; Protonation constants.

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References

    1. Aihara A, Nakanura Y, Nishida Y, Noda K (1986) Electrochemical behavior of copper (II)-dipeptide complexes in mixed solvent. Inorg Chim Acta 124(3):169–173. https://doi.org/10.1016/S0020-1693(00)85868-5 - DOI
    1. Arroyo M, Torres-Guzmán R, De la Mata I, Castillón MP, Carmen A (2000) Prediction of penicillin V acylase stability in water-organic cosolvent monophasic systems as a function of solvent composition. Enzyme Microb Technol 27(1–2):122–126. https://doi.org/10.1016/s0141-0229(00)00183-6 - DOI - PubMed
    1. Banarjee D, Laha AK, Chatterjee P, Bagchi S (1995) Preferential solvation in three component systems: evaluation of Kirkwood-Buff parameters. J Solut Chem 24:301–310. https://doi.org/10.1007/BF00979196 - DOI
    1. Barbosa J, Fonrodona G, Marqués I, Sanz-Nebot V, Toro I (1997) Solvent effects on protonation equilibria of peptides and quinolones by factor analysis applied to the correlation between dissociation constants and solvatochromic parameters in acetonitrile-water mixtures. Anal Chim Acta 351(1–3):97–405. https://doi.org/10.1016/S0003-2670(97)00234-1 - DOI
    1. Ben-Naim A (1988) Theory of preferential solvation of nonelectrolytes. Cell Biophys 12(1):255–269. https://doi.org/10.1007/BF02918361 - DOI - PubMed

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