Molecular stability of chemically modified collagen triple helices

FEBS Letters

Viola, Manuela¹  Forlino, Antonella¹  Giudici, Camilla¹  Tenni, Ruggero¹  Tira, M.Enrica¹ 

[1] Dipartimento di Biochimica ‘A. Castellani’, University of Pavia, via Taramelli 3b, 27100 Pavia, Italy

关键词: Collagen;    Chemical modification;    Molecular stability;    N0;    original unmodified sample;    Nm;    N-methylated sample;    Na and Naa;    samples N-acetylated with sulfosuccinimidyl acetate and acetic anhydride;    respectively;    CD;    circular dichroism;    SNHSAc;    sulfosuccinimidyl acetate;   

DOI  :  10.1016/S0014-5793(03)00715-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Ionic residues influence the stability of collagen triple helices and play a relevant role in the spontaneous aggregation of fibrillar collagens. Collagen types I and II and some of their CNBr peptides were chemically modified in mild conditions with two different protocols. Primary amino groups of Lys and Hyl were N-methylated by formaldehyde in reducing conditions or N-acetylated by sulfosuccinimidyl acetate. The positive charge of amino groups at physiological pH was maintained after the former modification, whereas it was lost after the latter. These chemical derivatizations did not significantly alter the stability of the triple helical conformation of peptide trimeric species. Also the enthalpic change on denaturation was largely unaffected by derivatizations. This implies that no significant variation of weak bonds, either in number or overall strength, and of entropy occur on modification. These properties can probably be explained by the fact that chemically modified groups maintain the ability to form hydrogen bonds.

【 授权许可】

Unknown