单线态氧
化学
藻蓝蛋白
单体
发色团
超分子化学
光化学
荧光
生物物理学
动态光散射
组合化学
作者
Ying Li,Richard E. Gillilan,Alireza Abbaspourrad
标识
DOI:10.1021/acs.biomac.1c01095
摘要
Environment-triggered protein conformational changes have garnered wide interest in both fundamental research, for deciphering in vivo acclimatory responses, and practical applications, for designing stimuli-responsive probes. Here, we propose a protein-chromophore regulatory mechanism that allows for manipulation of C-phycocyanin (C-PC) from Spirulina platensis by environmental pH and UV irradiation. Using small-angle X-ray scattering, a pH-mediated C-PC assembly-disassembly pathway, from monomers to nonamers, was unraveled. Such flexible protein matrices impart tunability to the embedded tetrapyrroles, whose photochemical behaviors were found to be modulated by protein assembly states. UV irradiation on C-PC triggers pH-dependent singlet oxygen (1O2) generation and conformational changes. Intermolecular photo-crosslinking occurs at pH 5.0 via dityrosine species, which bridges solution-based C-PC oligomers into unprecedented dodecamers and 24-mers. These supramolecular assemblies impart C-PC at pH 5.0, which significantly enhanced 1O2 yield, fluorescence, and photostability relative to those at other pH values, a finding that makes C-PC appealing for tumor-targeted photodynamic therapy.
科研通智能强力驱动
Strongly Powered by AbleSci AI