A Note on the Monophasic Non-specific Salmonella Types.

The discovery of phase variation by Andrewes (1922) has had a profound effect on the differentiation of Salmonella types. This phenomenon and the demonstration of heat-stable and heatlabile receptors by Weil and Felix (1920) form the basis for the modern classification of the paratyphoid group. Through the work of a number of investigators it has gradually been accepted that the motile Salmonella strains are divisible into four groups. These are as follows: A. Diphasic strains possessing the specific and non-specific phases of Andrewes (1922). B. Diphasic cultures which display a variation confined to two specific antigens. This is the alpha-beta phase variation of Kauffmann and Mitsui (1930). C. Monophasic cultures which exist only in the specific phase. D. Monophasic cultures which exist only in the non-specific phase. These are usually considered as the non-specific counterparts of diphasic cultures. It is with the fourth group, the forms generally regarded as being totally and permanently non-specific, that the present paper deals. This group is composed of five varieties: Binns, Kunzendorf, Voldagsen, Berlin and Puerto Rico. It is proposed to demonstrate that these organisms are not totally non-specific but are actually diphasic and possess specific components.