Multilocus enzyme electrophoresis (MEE) has been used extensively in the past in eukaryotic, and occasionally, prokaryotic genetics. It was only recently that the usefulness of MEE in bacterial genetics, systematics, and epidemiology, has been clearly demonstrated, essentially by the pioneering work of Selander and coworkers (1–3). Since then, numerous authors have been successfully applying MEE to an increasing number of bacteria. In MEE, cellular extracts are submitted to gel electrophoresis under nondenaturing conditions and enzymes are detected with specific staining methods (4,5).