Summary: The variations in Vibrio cholerae studied included changes from Ogawa to Inaba type, smooth→rough, and motile→non-motile. With a sloppy-agar technique it was possible to estimate the rate of formation of these variants (i.e. probable mutation rate 1 in 105 and 1 in 104, respectively). It was possible to show that the action of antiserum in promoting the change from Ogawa to Inaba was selective rather than mutagenic. With the other two variations studied no selective process had to be considered owing to their high spontaneous rate of appearance. It may be said that all three variations studied were due to spontaneous mutants in the parent cultures giving rise to these forms.
BalteanuI.1926; The receptor structure of Vibrio cholerae with observations on variations in cholera and cholera-like organisms.. J. Path. Bact. 29:251
VenkatramanK.V.1947; A note of the re-appearance of the Inaba type of V. cholerae in the Madras Province.. Report of the Scientific Advisory Board for the year1947, Indian Research Fund Association, New Delhi