reply to: T. Zhao & Y. Pan Nature Ecology & Evolution https://doi.org/10.1038/s41559-024-02432-6 (2024)

Our recent study¹ presents evidence for the preservation of remnant corneous β-proteins (CBPs) in experimentally matured and Mesozoic fossil feathers. This evidence was obtained using infrared spectroscopy and synchrotron-based X-ray spectroscopy. We argue that these analytical techniques, when combined, offer a new and rapid method for the detection of traces of ancient proteins. The use of sulfur X-ray spectroscopy provides evidence on CBP protein tertiary structure (disulfide bonds); infrared spectroscopy allows the identification of various protein secondary structures via deconvolution of the amide I and II bands. Our study demonstrates that deconvolution of the amide bands in spectra from experimentally matured and fossil feathers reveals a transformation of the β-sheets in CBPs to α-helices with increasing thermal maturation¹.

reply to: T. Zhao & Y. Pan Nature Ecology & Evolution https://doi.org/10.1038/s41559-024-02432-6 (2024)

我们最近的研究 ¹ 提供了在实验成熟和中生代化石羽毛中保存残余角质β蛋白（CBP）的证据。这一证据是通过红外光谱和基于同步加速器的 X 射线光谱获得的。我们认为，这些分析技术结合起来，为检测古代蛋白质的痕迹提供了一种新的快速方法。硫 X 射线光谱的使用提供了 CBP 蛋白质三级结构（二硫键）的证据；红外光谱可以通过酰胺 I 和 II 带的解卷积来识别各种蛋白质二级结构。我们的研究表明，对实验成熟羽毛和化石羽毛光谱中酰胺带的解卷积揭示了随着热成熟度的增加，CBP 中的 β 折叠转变为 α 螺旋 ¹ 。