A Highly Active Oxygen-Evolving Photosystem II Preparation from the Cyanobacterium Anacystis nidulans1

摘要

A highly active O2-evolving Photosystem (PS)-II fraction has been isolated from the cyanobacterium, Anacystis nidulans R2, using an isolation buffer containing high concentrations of sucrose and salts and subsequent solubilization of the thylakoid membranes with the detergent Triton X-100. The isolated fraction had very high PSII activity (2500 micromoles O2 per milligram chlorophyll per hour) and was largely depleted of PSI activity. Fluorescence emission spectra (77 K) and polypeptide analysis indicated that this preparation is highly enriched in PSII, but almost completely devoid of Cyt b6-f and PSI complexes.