Observations on morphological, cultural and biochemical changes concomitant with chloramphenicol resistance in Salmonella paratyphi B.

It is possible to induce chloramphenicol-resistance in Salmonella paratyphi B in vitro and to isolate mutants with different levels of resistance by different techniques. The resistance is invariably accompanied by definite changes in the morphological, cultural and biochemical properties. The degree of resistance and the conditions of isolation seem to influence the biological properties of the mutants. The higher the level of resistance, the greater will be the diversion from the normal.