Institute of Mathematics and Physics, UTP University of Science and Technology, al. Kaliskiego 7, 85-796 Bydgoszcz, Poland.
Soft Matter. 2018 Nov 14;14(44):8997-9004. doi: 10.1039/c8sm01388h.
Hyaluronic acid and phospholipids are two components in the synovial joint cavity that contribute to joint lubrication synergistically. Molecular dynamics simulations were performed and hydrogen bonds in hyaluronic acid were analyzed to identify specific sites that are responsible for its physical cross-linking. Two molecular masses of hyaluronic acid, 10 kDa and 160 kDa, were considered. We use molecular dynamics simulations and the small world network approach to investigate dynamic couplings using a distance map applied to oxygen atoms in a chain of hyaluronic acid in the presence of phospholipids and water. The distance characterizing the coupling can be defined in various ways to bring out the most evident differences between various scenarios of the polymer chain conformation We show herein a physical distance understood as H-bond length and classes of these distances which are defined in a coarse-grained picture of the molecule. Simulation results indicate that addition of phospholipids has little influence on hyaluronic acid crosslinking. However, longer chains and addition of lipids promote appreciably long lasting (resilient) networks that may be of importance in biological systems. Specific sites for hydrogen bonding of phospholipids to hyaluronic acid have also been identified.
透明质酸和磷脂是关节滑液腔中的两种成分，它们协同作用，有助于关节润滑。我们进行了分子动力学模拟，并分析了透明质酸中的氢键，以确定负责其物理交联的特定部位。我们考虑了两种分子量的透明质酸，即 10 kDa 和 160 kDa。我们使用分子动力学模拟和小世界网络方法，通过在存在磷脂和水的情况下应用于透明质酸链中的氧原子的距离图来研究动态耦合。可以通过多种方式定义表征耦合的距离，以突出聚合物链构象的各种情况下最明显的差异。我们在此展示了一种物理距离，理解为氢键长度，以及在分子的粗粒度图中定义的这些距离的类别。模拟结果表明，磷脂的添加对透明质酸的交联几乎没有影响。然而，较长的链和添加脂质促进了明显持久（有弹性）的网络，这在生物系统中可能很重要。还确定了磷脂与透明质酸氢键的特定结合部位。
