The diastereomeric assembly of polylysine is the low-volume pathway for preferential formation of beta-sheet aggregates.
The diastereomeric assembly of polylysine is the low-volume pathway for preferential formation of beta-sheet aggregates.
复制标题
聚赖氨酸的非对映体组装是优先形成β-折叠聚集体的低体积途径。
DOI：
--
复制
发表时间：
2004
影响因子：
15
通讯作者：
R. Winter
中科院分区：
文献类型：
--
作者：
W. Dzwolak;Revanur Ravindra;C. Nicolini;R. Jansen;R. Winter
左旋和右旋聚赖氨酸链（聚（D-赖氨酸）和聚（L-赖氨酸））的相互作用导致形成聚集的β-折叠结构（和淀粉样原纤维）的倾向显著增加，这通过α-螺旋至β-折叠转变的温度降低约15 ℃来反映。虽然13-19 mL x mol（-1）的相对体积膨胀伴随着单一对映异构体中的α-至-β-转变，但这对于混合物不成立，其沿着实质上更负的热容变化，指出转变的较低溶剂熵成本作为非对映异构体聚集的可能热力学驱动力。潜在的溶剂化机制可能是体内自发蛋白质聚集的决定性因素之一，因此，可能揭示淀粉样蛋白相关疾病的分子基础。
The interaction of left- and right-handed polylysine chains (poly(D-lysine) and poly(L-lysine)) results in a dramatic increase in the propensity to form aggregated beta-sheet structure (and amyloid-like fibrils), which is reflected by an approximately 15 degrees C decrease of temperature of the alpha-helix-to-beta-sheet transition. While a relative volume expansion of 13-19 mL x mol(-1) accompanies the alpha-to-beta-transition in a single enantiomer, this does not hold true for the mixture, which, along with substantially more negative heat capacity changes, points to a lower solvent-entropy cost of the transition as the possible thermodynamic driving force of the diastereomeric aggregation. The underlying solvational mechanism may be one of the decisive factors responsible for the spontaneous protein aggregation in vivo and, as such, may shed new light on the molecular basis of amyloid-associated diseases.