Inhibition of amino acid transport in Escherichia coli cells and its cell membranes

In earlier reports Simon et al. [ 1,2] found that in Escherichia coli cells levorphanol stimulates the efflux and inhibits the uptake of putrescine and the transport of amino acids. Greene and Magasanik [3] have shown that high concentrations of levallorphan cause permeability changes which lead to a loss of ATP and of thiomethylgalactoside (TMG). Gale [4] was able to show that heroin, levorphanol and levallorphan interfere with amino acid transport into the pool of staphylococci, and that [5] this treatment results in a stimulated turnover of the phospholipids. These observations made it highly probable that these drugs affect some function of the cell membrane. With low concentrations that hardly affect growth we observed that adsorption of MS-2 phages [6] and the formation of mating pairs during R-factor transfer [7] were inhibited. These findings also point to changes in the cell membranes. In the present paper we show that with low concentrations of levallorphan the uptake of arginine is inhibited, and that the same type of inhibition of arginine uptake occurs in whole cells as well as in membrane preparations.