Interaction of ethidium bromide with yeast cells investigated by electron probe X-ray microanalysis.

K efflux provoked by ethidium proceeds partially as an all-or-none effect by which the diffusion barrier for K is disrupted and partially from still intact cells, presumably by exchange against ethidium. This is shown by the application of an electron probe microanalysis X-ray technique by which the K content of a number of individual cells is analyzed. [ABSTRACT FROM AUTHOR]