On the uptake of nystatin by Saccharomyces cerevisiae. 1 Basic considerations.

The uptake of nystatin by sensitive Saccharomyces cerevisiae cells has been studied as a function of temperature and nystatin concentration. Following analysis of the data, kinetic rate constants and a monolayer capacity are calculated. This shows that c 13 X more nystatin is taken up than can be supported by the cell surface. The process is accompanied by an activation energy of 41.6 kJ mol-1. It is suggested that these data support a rapid uptake process onto the cell wall followed by a slower diffusion process through the wall to the membrane.