Abstract
For a crystallization study, purification methods for F1 -ATPase from a thermophilic bacterium, PS3, and its major subunits, β and α, have been improved. The improvement depended on the introduction of dye-ligand chromatography columns to the previously adopted array of chromatography columns: a Blue-B (a blue dye bound to agarose) column was introduced for the F1 preparation, a Green-A column (a green dye attached to agarose) for the β subunit, and a Blue-A (another blue dye, Cibacron Blue 3GA, bound to agarose) column for the α subunit. The improved preparations of all the proteins had purities of nearly 99%. Using the highly purified preparations of the proteins, crystallization conditions were searched for in a systematic way. Large plate crystals (0.2 X 0.5 X 0.5 mm) of F1 were grown from a polyethylene glycol solution. However, neither of the subunits was crystallized, in spite of extensive search for crystallization conditions.
