Purification, crystallization and preliminary X-ray diffraction analysis of water-soluble chlorophyll-binding protein from Chenopodium album

A water-soluble chlorophyll-binding protein (WSCP) with photoconvertibility from Chenopodium album was extracted, purified and crystallized in a darkroom. Green crystals suitable for data collection appeared in about 10 d. A native data set was collected to 2.0 A resolution at 100 K. The space group of the crystal was determined to be orthorhombic I222 or I212121, with unit-cell parameters a = 48.13, b = 60.59, c = 107.21 A. Preliminary analysis of the X-ray data indicated that there is one molecule per asymmetric unit.