Isolation and characterization of oxygen-evolving photosystem II particles and photosystem II core complex from the filamentous cyanobacterium Spirulina platensis
Abstract
Photosystem (PS) II particles retaining a high rate of O-2 evolution were isolated from the mesophilic filamentous cyanobacterium, Spirulina platensis. To achieve high production of PSII complexes in the cells, irradiance from halogen incandescent lamps was used.
Disruption of cells by vibration of glass beads proved to be the most suitable procedure for isolation of thylakoid membranes. The selectivity of detergents for PSII particle preparation rose in the order of Triton X-100 < decyl-beta-D-glucopyranoside < dodecyldimethyl-aminooxide < n-heptyl-beta-D-thioglucoside < N-dodecyl-N,N-dimethylammonio-3-propane sulphonate < n-octyl-beta-thioglycoside < octylglucoside < n-dodecyl-beta-D-maltoside.
The last four detergents yielded extracts, from which pure PSII particles not contaminated by PSI complexes could be obtained by sucrose-gradient centrifugation (20-45%) at the 43% sucrose level.