Growth and Development Section, AgResearch Lincoln Research Centre, New Zealand.
J Photochem Photobiol B. 2010 Feb 12;98(2):118-27. doi: 10.1016/j.jphotobiol.2009.11.008. Epub 2009 Dec 2.
Photo-oxidation of proteinaceous fibres correlates directly to lowered appearance retention and performance, with particular commercial significance for wool and human hair. We here outline the first detailed proteomic evaluation of differential photo-oxidation occurring in the cuticle and cortex of wool fibres. After exposure of whole wool to UVB irradiation, physical disruption techniques designed to minimise further oxidative modification were utilised to prepare enriched cuticle and cortex fractions. This was followed by comprehensive redox proteomic analyses of photo-oxidation via the location within the fibre components of modifications to aromatic residues. An oxidative classification system was developed and applied to provide further insight into differential photo-oxidation. These results were compared with coloration changes observed within the cuticular and cortical components of the fibre. In this study, although the cuticle was observed to have a higher level of baseline oxidation, the cortex exhibited significantly higher levels of photo-oxidation under UVB irradiation. These proteomic results were supported by the observation of significantly higher photoyellowing within the cortex than within the cuticle. It has been assumed that fibre photo-oxidation was predominantly confined to the wool cuticle, and that changes within the cuticle had the greatest effect on appearance retention. These results provide new insight into the contribution of the cortex to photo-induced discoloration of proteinaceous animal fibres.
蛋白质纤维的光氧化与外观保持和性能的降低直接相关，对羊毛和人类头发具有特殊的商业意义。我们在这里概述了对羊毛纤维角质层和皮质中发生的差异光氧化的首次详细蛋白质组学评估。在将整个羊毛暴露于 UVB 辐射后，利用旨在最小化进一步氧化修饰的物理破坏技术来制备富含角质层和皮质的级分。然后通过在纤维成分内定位芳香残基的修饰来进行全面的氧化还原蛋白质组学分析，以进行光氧化。开发了一种氧化分类系统，并应用该系统进一步深入了解差异光氧化。将这些结果与纤维角质层和皮质成分内观察到的着色变化进行了比较。在这项研究中，尽管角质层被观察到具有更高水平的基线氧化，但皮质在 UVB 照射下表现出明显更高水平的光氧化。这些蛋白质组学结果得到了皮质内的光黄化明显高于角质层内的观察结果的支持。人们一直认为纤维光氧化主要局限于羊毛角质层，并且角质层内的变化对外观保持的影响最大。这些结果提供了对蛋白质动物纤维光诱导变色中皮质贡献的新见解。
