Ribosome recycling factor (RRF) plays a central role during the recycling of ribosomes in the final step of protein biosynthesis in prokaryotes and is therefore a favourable target for the development of new antibiotics. The crystal structure of Escherichia coli RRF has been reported to have an open L-shaped conformation, while other RRFs from thermophilic bacteria have a strict L-shaped conformation [Yun et al. (2000), Acta Cryst. D56, 84-85]. Wild-type E. coli RRF has so far not been crystallized free from bound detergent. Here, a mutant of RRF, Arg132Gly, has been crystallized without any detergent. A complete data set from a crystal of this mutant obtained by the hanging-drop vapour-diffusion method has been collected at 2.2 A resolution using synchrotron radiation at 100 K. The crystal belongs to the monoclinic space group P2(1), with unit-cell parameters a = 46.02, b = 49.27, c = 49.37 A, beta = 110.1 degrees. The currently refined structure indicates that RRF has a tRNA-like L-shaped conformation.