Effects of staphylococcin 1580 on cells and membrane vesicles of Bacillus subtilis W23

1. Uptake of L-glutamic acid is inhibited, and preaccumulated L-glutamic acid is released from Bacillus subtilis cells treated with staphylococcin 1580. Uptake of alpha-methylglycoside is enhanced at low bacteriocin concentrations and inhibited by excess bacteriocin. 2. Inhibition of amino acid uptake into membrane vesicles is somewhat less sensitive to staphylococcin 1580 than uptake into whole cells under similar conditions, when the bacteriocin concentration is expressed per weight unit of membrane protein. Inhibition of uptake into vesicles is independent of the electron donor system used, but varies with different substrates. 3. Influx of L-glutamic acid into vesicles under anaerobic conditions is severely hampered by staphylococcin 1580. The L-glutamic acid carrier functions are slightly affected only. 4. Staphylococcin 1580 abolished the membrane potential induced by respiration or by a potassium diffusion potential in the presence of valinomycin, as measured with the fluorescent dye 3,3'-dipropylthiadicarbocyanine. 5. The effects of staphylococcin 1580 on cells and membrane vesicles allowed the classification into three groups with different sensitivity to the staphylococcin concentration.