دورية أكاديمية

Entropic elasticity controls nanomechanics of single tropocollagen molecules

التفاصيل البيبلوغرافية
العنوان: Entropic elasticity controls nanomechanics of single tropocollagen molecules
المؤلفون: Markus J. Buehler, Sophie Y. Wong Y
المساهمون: The Pennsylvania State University CiteSeerX Archives
المصدر: http://web.mit.edu/mbuehler/www/papers/biophys_j-TC.pdfTest.
سنة النشر: 2007
المجموعة: CiteSeerX
الوصف: We report molecular modeling of stretching single molecules of tropocollagen, the building block of collagen fibrils and fibers that provide mechanical support in connective tissues. For small deformation, we observe a dominance of entropic elasticity. At larger deformation, we find a transition to energetic elasticity, which is characterized by first stretching and breaking of hydrogen bonds, followed by deformation of covalent bonds in the protein backbone, eventually leading to molecular fracture. Our force-displacement curves at small forces show excellent quantitative agreement with optical tweezer experiments. Our model predicts a persistence length jp 16 nm, confirming experimental results suggesting that tropocollagen molecules are very flexible elastic entities. We demonstrate that assembly of single tropocollagen molecules into fibrils significantly decreases their bending flexibility, leading to decreased contributions of entropic effects during deformation. The molecular simulation results are used to develop a simple continuum model capable of describing an entire deformation range of tropocollagen molecules. Our molecular model is capable of describing different regimes of elastic and permanent deformation, without relying on empirical parameters, including a transition from entropic to energetic elasticity.
نوع الوثيقة: text
وصف الملف: application/pdf
اللغة: English
العلاقة: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.421.9158Test; http://web.mit.edu/mbuehler/www/papers/biophys_j-TC.pdfTest
الإتاحة: http://web.mit.edu/mbuehler/www/papers/biophys_j-TC.pdfTest
حقوق: Metadata may be used without restrictions as long as the oai identifier remains attached to it.
رقم الانضمام: edsbas.78AB7D5A
قاعدة البيانات: BASE