UPTAKE OF RUBIDIUM AND PHOSPHATE IONS BY POLYSACCHARIDE-PRODUCING BACTERIA

Abstract

This study deals with ion uptake by Leuconostoc dex-tranicum, L. mesenteroides, Streptococcus salivarius and Azotobacter indicum. With the exception of A. indicum, these organisms, depending upon the C source present in the growth medium, could be grown either with or without abundant poly-saccharide formation. Ion uptake by bacteria with copious polysaccharide, from solutions tagged with radioactive Rb86 or P32 was found to be from 2 to 20 times as great as the ion uptake observed with bacteria grown without abundant slime or capsule formation. The results of this study seem compatible with the hypothesis that the polysaccharide present in bacterial and higher plant cells is one of the important ion binding compounds responsible for initial ion uptake by the cell. A high initial uptake followed by a loss or exchange of ions was observed with living cells and seemed to be ultimately associated with the metabolism of the cell.