Wynn R M, Malkin R
Division of Molecular Plant Biology, University of California, Berkeley 94720.
Biochemistry. 1988 Aug 9;27(16):5863-9. doi: 10.1021/bi00416a007.
Plastocyanin has been covalently cross-linked to photosystem I (PSI) by using a water-soluble cross-linker, N-ethyl-3-[3-(dimethylamino)propyl]carbodiimide. The cross-linking reaction is light stimulated and results in the disappearance of a single 19-kDa subunit of PSI with the formation of a new protein-staining component of 31 kDa. The new product at 31 kDa reacts with both plastocyanin and 19-kDa subunit antibodies. Carboxyl group modified plastocyanin does not form a cross-linked product with PSI, implying that the negatively charged surface-exposed groups on plastocyanin are necessary to stabilize binding. These results demonstrate a specific interaction of plastocyanin with PSI and further implicate a specific protein to which plastocyanin binds to facilitate electron transfer to the P700 reaction center.
通过使用水溶性交联剂N-乙基-3-[3-(二甲基氨基)丙基]碳二亚胺，质体蓝素已与光系统I（PSI）共价交联。交联反应受光刺激，导致PSI的一个19 kDa亚基消失，并形成一个新的31 kDa蛋白质染色组分。31 kDa的新产物与质体蓝素抗体和19 kDa亚基抗体都发生反应。羧基修饰的质体蓝素不与PSI形成交联产物，这意味着质体蓝素表面带负电荷的暴露基团对于稳定结合是必需的。这些结果证明了质体蓝素与PSI之间的特异性相互作用，并进一步暗示质体蓝素与之结合以促进电子传递至P700反应中心的特定蛋白质。
