In situ monitoring of protein aggregation via clusteroluminescence

Abstract

Proteins, showing non-conjugated and nonaromatic structures, have been discovered with abnormal visible emission at the clustering state, namely clusteroluminescence (CL). Exploring the practical application of CL is one of the thorny and urgent issues in this area. In this work, the CL properties of the hen egg white lysozyme (HEWL) and bovine serum albumin (BSA) are systematically studied, which shows a typical clusterization-triggered emission (CTE) effect. Moreover, the CL is successfully utilized to monitor the processes of amyloid fibrillation for HEWL and heating-induced denaturation for HEWL and BSA. For example, the CL can monitor the growth kinetics of lysozyme fibrils in the same way as conventional fluorescent probes. More importantly, CL exhibits a unique advantage in monitoring the nucleation phase of fibers. This study broadens the application of CL and enriches the strategies to monitor protein aggregation.