The occurrence of three flagellar phases in Arizona serotypes.

Since Andrewes (1922) described •gspecific•h and •gnonspecific•h flagellar antigens in several Salmonella types, the diphasic state has been recognized in hundreds of Salmo nella serotypes and has been recognized also in the Arizona group (Edwards and West, 1945). Similar variations have been found in the Escherichia freundii (Citobacter) group by Edwards (1946), in the Hafnia group by Deacon (1952), and in the Aerobacter clo acae (Cloaca) group by Sakazaki and Namioka (1960). Salmonella types which had complex phases and which gave rise to simpler types through loss variation were reported. Edwards and Bruner (1942) described S. salinatis (4, 12:d, e, h:d, e, n, z15) which could be changed irreversibly to S. san diego (4, 12:e, h:e, n, z15) while Edwards, Kauffmann and Huey (1957) found that S. mont gomery (11:d, a:d, e, n, z15) was changed to S. luciana (11:a:e, n, z15). Both of the changes resulted from the permanent loss of the common major antigenic constitu ent of phases 1 and 2 through cultivation in semisolid medium which contained d serum. Further, Edwards (1950) observed spontaneous irreversible segregation of e, h phases from more complex d, e, h phases. •gArtificial•h or induced phases often have been obtained by cultivation of salmonellae in homologous flagellar antisera. Thus, Kauffmann (1936) obtained j phases by cultivation of S, typhi in d serum and Edwards and Bruner (1939) and Bruner and Edwards (1941) obtained induced phases from S, abortus equi and S.