The Effect of Electrolytes Present in the Growth Media upon the Electrophoretic Mobility of Escherichia coli

Abstract

The organisms were cultured in peptone solutions containing salts in varying concns., the peptone salt solutions replaced by distilled water, and the mobilities determined with a Northrop-Kunitz micro-cataphoresis cell. Continued washing with water of coli grown in the presence of CaCl2 increased the migration velocity to a constant value; with Na2SO4 the migration velocity was first increased and then decreased to the same constant value. The mobility was not influenced by the age of the culture up to 28 hrs. The well known mobility-concn. curves determined with salts present in the suspension media were not obtained.