Proposals Concerning the Higher Taxa of Bacteria

Names are proposed for divisions, classes, and some orders of bacteria. The kingdom Procaryotae Murray 1968 is divided into three divisions: Gracilicutes divisio nov., Firmacutes divisio nov., and Mollicutes Edward and Freundt 1967, for organisms having, respectively, a gram-negative cell wall, a gram-positive cell wall, and no cell wall. Gracilicutes comprises the class Photobacteria classis nov. for organisms having a phototrophic metabolism and Scoto bacteria classis nov. for those having a nonphototrophic metabolism. Photobacteria is divided into two subclasses: Oxyphotobacteriae subclassis nov. for organisms that carry out an aerobic phototrophic metabolism, using water as an electron donor and producing oxygen, and Anoxyphotobacteriae subclassis nov. for those that have an anaerobic phototrophic metabolism. Oxyphotobacteriae comprises the orders Cyano bacteriales ordo nov. (formerly blue-green algae) and Prochlorales Lewin 1977. Anoxyphoto bacteriae contains the order Rhodospirillales Pfennig and Triiper 1971 and Chlorobiales ordo nov. The possible need of a fourth division to include organisms that have a rigid cell wall but do not contain peptidoglycan is noted. The name proposed for such a division is Mendocutes, that is, organisms having a cell wall with faults and blemishes.