Re-emerging structures: continuing crystallography of the bacterial reaction centre

The reaction centre is nature's solar battery, and is found in a number of variations on a common theme in plants, algae and photosynthetic bacteria. During the last 20 years, a combination of X-ray crystallography, spectroscopy and mutagenesis has provided increasingly detailed insights into the mechanism of light energy transduction in the bacterial reaction centre. This mini-review looks at the application of X-ray crystallography to the bacterial reaction centre, focussing in particular on recent information on the structural consequences of site-directed mutagenesis, the roles played by water molecules in the reaction centre, the mechanism of ubiquinone reduction, and studies of the phospholipid environment of the protein.