Proteinaceous nanomaterials and, in particular, virus-like particles (VLPs) have emerged as robust and uniform platforms that are seeing wider use in biomedical research. However, there are a limited number of bioconjugation reactions for functionalizing the capsids, and very few of those involve functionalization across the supramolecular quaternary structure of protein assemblies. In this work, we exploit the recently described dibromomaleimide moiety as part of a bioconjugation strategy on VLP Qβ to break and rebridge the exposed and structurally important disulfides in good yields. Not only was the stability of the quaternary structure retained after the reaction, but the newly functionalized particles also became brightly fluorescent and could be tracked in vitro using a commercially available filter set. Consequently, we show that this highly efficient bioconjugation reaction not only introduces a new functional handle “between” the disulfides of VLPs without compromising their thermal stability but also can be used to create a fluorescent probe.

中文翻译：

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在病毒样颗粒中跨四级结构的荧光功能化。

蛋白质纳米材料，尤其是病毒样颗粒（VLP）已成为坚固且统一的平台，在生物医学研究中得到了广泛的应用。然而，用于使衣壳功能化的生物缀合反应的数量有限，并且很少有涉及跨蛋白质组装体的超分子四级结构进行功能化的反应。在这项工作中，我们利用最近描述的二溴马来酰亚胺部分作为VLPQβ生物共轭策略的一部分，以高收率打破和重排暴露的和结构上重要的二硫化物。反应后不仅保留了四级结构的稳定性，而且新功能化的粒子也变得明亮的荧光，可以使用市售的过滤器进行体外追踪。所以，