Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Sorbonne Université, CNRS, Paris F-75005, France.
SOLEIL Synchrotron, Saint Aubin 91190, France.
Biomacromolecules. 2024 Sep 9;25(9):6181-6187. doi: 10.1021/acs.biomac.4c00860. Epub 2024 Aug 3.
Controlling the assembly of high-order structures is central to soft-matter and biomaterial engineering. Angle-resolved linear dichroism can probe the ordering of chiral collagen molecules in the dense state. Collagen triple helices were aligned by solvent evaporation. Their ordering gives a strong linear dichroism (LD) that changes sign and intensity with varying sample orientations with respect to the beam linear polarization. Being complementary to circular dichroism, which probes the structure of chiral (bio)molecules, LD can shift from the molecular to the supramolecular scale and from the investigation of the conformation to interactions. Supported by multiphoton microscopy and X-ray scattering, we show that LD provides a straightforward route to probe collagen alignment, determine the packing density, and monitor denaturation. This approach could be adapted to any assembly of chiral (bio)macromolecules, with key advantages in detecting large-scale assemblies with high specificity to aligned and chiral molecules and improved sensitivity compared to conventional techniques.
控制高级结构的组装是软物质和生物材料工程的核心。角度分辨线性二色性可探测密集状态下手性胶原蛋白分子的有序性。通过溶剂蒸发使胶原三螺旋排列。它们的有序性产生强烈的线性二色性（LD），随着样品相对于光束线性偏振的取向变化，LD 的符号和强度发生变化。LD 与圆二色性互补，圆二色性探测手性（生物）分子的结构，LD 可以从分子尺度转移到超分子尺度，从构象研究转移到相互作用研究。多光子显微镜和 X 射线散射的支持下，我们表明 LD 提供了一种直接的方法来探测胶原蛋白的排列，确定堆积密度，并监测变性。这种方法可以适应任何手性（生物）大分子的组装，与传统技术相比，它具有检测大规模组装的高特异性和对排列和手性分子的高灵敏度的关键优势。
