[Effect of an electrical field on Alcaligenes eutropha cells]

The electrophoretic mobility and electrokinetic potential of the hydrogen-oxidizing bacterium Alcaligenes eutropha were measured using microelectrophoresis. The cells were shown to bear a negative charge of ca. 2 x 10(-8) coulomb/cm2. The electrokinetic potential causing electrophoresis of the bacterium changes from negative values in an alkaline or neutral medium to positive values in an acid medium, and the isoelectric point is at pH approximately 6.0. The electrophoretic mobility of the bacterium rises with an increase of the ionic strength of solutions. The electric field of a low voltage (up to 5 V/cm) does not induce a noticeable change in the behaviour and growth of the bacterium under the autotrophic conditions.