Coliform “Mutants,” with Respect to the Utilization of Citrate

Abstract

The described coliform citrate "mutant" can be so handled as to yield true breeding lines of the unstable variant, of a stable positive citrate-utilizer, and of a stable negative citrate-utilizer. The method used in obtaining these 3 lines is descr. The probability that such forms represent contaminations or mixtures is ruled out. New material, valuable for the study of bacterial genetics, has thus been obtained, and the evidence that bacterial taxonomy should be conservative has been added to. Improved methods of study for this "mutant" and for others longer known to bacteriologists are needed. Differences in stability may exist in different strains of certain bacterial spp.; in occasional studies the results obtained may therefore depend on the nature of the strains utilized, making it possible for good workers in different places to obtain conflicting results.