Ma Mingming, Paredes Angel, Bong Dennis
Department of Chemistry, Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, USA.
J Am Chem Soc. 2008 Nov 5;130(44):14456-8. doi: 10.1021/ja806954u. Epub 2008 Oct 14.
Multivalency and preorganization are fundamental aspects of molecular recognition at the lipid membrane-water interface and can render weak monomeric binding interactions selective and robust; this concept is important throughout biology, biotechnology, and materials science. Though hydrogen bonding is typically weakened in water, intramembrane hydrogen bonding between native lipids has been well-studied and is thought to contribute to lipid bioactivity and membrane function. We hypothesized that avidity and preorganization effects at the lipid-water interface could overcome solvent competition and allow for selective hydrogen-bond recognition between small, unstructured components. We have found that electrostatically identical vesicular membranes composed of cyanuric acid and melamine functionalized phospholipids 1 and 2 undergo selective apposition, fusion and adhesion in suspension and on solid support, indicating that their well-known low-dielectric hydrogen bonding properties translate effectively to the lipid-water interface. This work is notable and of general interest given the few detailed studies of aqueous phase hydrogen-bonding systems; we have extensively characterized this system, gaining structural, functional, and thermodynamic data. Furthermore, we have found that the designed lipid-lipid headgroup interactions result in dramatic alteration of the lipid phase morphology, providing insight into the coupling of molecular interactions with assembly state. As such, this work contributes to our understanding of fundamental phenomena such as molecular recognition at the lipid-water interface membrane chemistry and further illustrates the general possibility of designing selective hydrogen-bonding adhesive interactions from simple starting materials at other polar-apolar interfaces; this could have numerous materials and biotechnological applications.
多价性和预组织是脂质膜 - 水界面分子识别的基本方面，可使弱的单体结合相互作用具有选择性和稳健性；这一概念在整个生物学、生物技术和材料科学中都很重要。尽管氢键在水中通常会减弱，但天然脂质之间的膜内氢键已得到充分研究，并被认为有助于脂质生物活性和膜功能。我们假设脂质 - 水界面的亲和力和预组织效应可以克服溶剂竞争，并允许在小的、无结构的组分之间进行选择性氢键识别。我们发现，由氰尿酸和三聚氰胺功能化磷脂1和2组成的静电相同的囊泡膜在悬浮液和固体支持物上会发生选择性并置、融合和粘附，这表明它们众所周知的低介电常数氢键性质有效地转化到了脂质 - 水界面。鉴于对水相氢键系统的详细研究较少，这项工作值得关注且具有普遍意义；我们对该系统进行了广泛表征，获得了结构、功能和热力学数据。此外，我们发现设计的脂质 - 脂质头基相互作用会导致脂质相形态发生显著改变，从而深入了解分子相互作用与组装状态的耦合。因此，这项工作有助于我们理解脂质 - 水界面分子识别等基本现象、膜化学，并进一步说明了从简单起始材料在其他极性 - 非极性界面设计选择性氢键粘附相互作用的一般可能性；这可能有许多材料和生物技术应用。
