Identification of the plastocyanin binding subunit of photosystem I |
| |
Authors: | A R Mire-Sluis A V Hoffbrand R G Wickremasinghe |
| |
Institution: | Department of Haematology, Royal Free Hospital and School of Medicine, London, England. |
| |
Abstract: | Plastocyanin is specifically cross-linked by incubation with N-ethyl-3-3-(dimethylamino)propyl]carbodiimide (EDC) to a subunit of photosystem I in stroma lamellae and in isolated photosystem I complex. SDS-PAGE shows the disappearance of a 18.5 kDa subunit and the appearance of a new 31.5 kDa protein which was recognized by anti-plastocyanin antibodies. The isolated subunit was identified by its N-terminal amino acid sequence as the mature peptide coded by the nuclear gene psaF Steppuhn et al. (1988) FEBS Lett. 237, 218–224]. P700+ was reduced by cross-linked plastocyanin with the same halftime of 13 μs as found in the native complex. This is evidence that cross-linking conserved the orientation of the complex and that the 18.5 kDa subunit provides the conformation of photosystem I necessary for the extremely rapid electron transfer from plastocyanin to P700+. |
| |
Keywords: | Photosynthesis Photosystem I Subunit III Peptide sequencing Plastocyanin (Spinach) |
本文献已被 ScienceDirect 等数据库收录! |