[Aggregation of poly-L-proline in aqueous solution].

B A Grishkovskiĭ; T B Khromova; Iu A Lazarev

PubMed · 7242532

[Aggregation of poly-L-proline in aqueous solution].

B A Grishkovskiĭ·T B Khromova·Iu A Lazarev

Abstract

Infrared spectra were measured for both aqueous (D2O) solution and the solid state of form II poly-L-proline in the amide I region as a function of the temperature. The temperature range includes the region where a precipitation is known to occur. From the analysis of spectra of hydrated films and aqueous solutions at different temperatures one can see that there are some peptide C = O-groups which are bounded with water. From this study it has been concluded that poly-L-proline exists in aggregate form even at temperatures lower that required for precipitation. It is supposed that poly-L-proline forms the aggregates including at least 40--50 polypeptide chains with hexagonal packing. At heating crystallisation of such aggregates occurred and it causes precipitation of poly-L-proline II.

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Kinetics Macromolecular Substances Peptides Proline Solutions Spectrophotometry, Infrared Temperature Water English Abstract Journal Article

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B A Grishkovskiĭ, T B Khromova, Iu A Lazarev. [Aggregation of poly-L-proline in aqueous solution].. https://pubmed.ncbi.nlm.nih.gov/7242532/

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