Procaryotic Genera Domain "Bacteria" Woese et al. 1990 Phylum Proteobacteria Garrity and Holt 2001 see Phylum Proteobacteria Garrity et al. 2005 Class "Gammaproteobacteria" nom. inval. see Class Gammaproteobacteria Garrity et al. 2005 Order "Enterobacteriales" Garrity and Holt 2001 nom. nud. [monotypic] Family Enterobacteriaceae Rahn 1937 (Approved Lists 1980) Genus Klebsiella Trevisan 1885 (Approved Lists 1980)