2024-03-29T12:39:04Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/172102019-02-14T08:25:32Zcom_10261_75com_10261_6col_10261_328
00925njm 22002777a 4500
dc
Seibert, Michael
author
Picorel Castaño, Rafael
author
Rubin, Andrew B.
author
Connolly, John S.
author
1988-06
Photosystem II reaction center (RC) preparations isolated from spinach (Spinacea oleracea) by the Nanba-Satoh procedure (O Nanba, K Satoh 1987 Proc Natl Acad Sci USA 84: 109-112) are quite labile, even at 4°C in the dark. Simple spectroscopic criteria were developed to characterize the native state of the material. Degradation of the RC results in (a) blue-shifting of the red-most absorption maximum, (b) a shift of the 77 K fluorescence maximum from 682 nm to 670 nm, and (c) a shift of fluorescence lifetime components from 1.3-4 nanoseconds and >25 nanoseconds to 6-7 nanoseconds. Fluorescence properties at 77 K seem to be a more sensitive spectral indicator of the integrity of the material. The >25 nanosecond lifetime component is assigned to P680+ Pheophytin– recombination luminescence, which suggests a correlation between the observed spectral shifts and the photochemical competence of the preparation. Substitution of lauryl maltoside for Triton X-100 immediately after RC isolation stabilizes the RCs and suggests that Triton may be responsible for the instability.
Plant Physiology 87:303-306 (1988)
0032-0889
http://hdl.handle.net/10261/17210
1532-2548
Spectral, Photophysical, and Stability Properties of Isolated Photosystem II Reaction Center