Temperature induced denaturation of collagen in acidic solution

• Published in: Biopolymers 2007-07, Vol.86 (4), p.282-287
• Main Authors: Mu, Changdao, Li, Defu, Lin, Wei, Ding, Yanwei, Zhang, Guangzhao
• Format: Article
• Language: English
• Subjects: Acetic Acid - metabolism; Animals; Cattle; collagen; Collagen - metabolism; denaturation; denaturation, light scattering; light scattering; Protein Denaturation; Solutions; Temperature; Transition Temperature
• ISSN: 0006-3525; 1097-0282
• DOI: 10.1002/bip.20742

The denaturation of collagen solution in acetic acid has been investigated by using ultra‐sensitive differential scanning calorimetry (US‐DSC), circular dichroism (CD), and laser light scattering (LLS). US‐DSC measurements reveal that the collagen exhibits a bimodal transition, i.e., there exists a shoulder transition before the major transition. Such a shoulder transition can recover from a cooling when the collagen is heated to a temperature below 35°C. However, when the heating temperature is above 37°C, both the shoulder and major transitions are irreversible. CD measurements demonstrate the content of triple helix slowly decreases with temperature at a temperature below 35°C, but it drastically decreases at a higher temperature. Our experiments suggest that the shoulder transition and major transition arise from the defibrillation and denaturation of collagen, respectively. LLS measurements show the average hydrodynamic radius 〈Rh〉, radius of gyration 〈Rg〉of the collagen gradually decrease before a sharp decrease at a higher temperature. Meanwhile, the ratio 〈Rg〉/〈Rh〉 gradually increases at a temperature below ∼ 34°C and drastically increases in the range 34–40°C, further indicating the defibrillation of collagen before the denaturation. © 2007 Wiley Periodicals, Inc. Biopolymers 86: 282–287, 2007. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at [e-mail]