ASSOCIATION OF SOME ENTEROBACTERIA WITH THE INTESTINAL MUCOSA OF MOUSE IN RELATION TO THEIR PARTITION IN AQUEOUS POLYMER TWO-PHASE SYSTEMS

Abstract

The association of enterobacteria with mouse intestinal mucosa was investigated by pumping heat-killed, radioactively-labeled bacteria through the gut lumen in vitro. Approximately 20 cm of the small intestine proximal to the ileo-cecal valve was rinsed, excised and maintained in an organ bath. By using 2 different bacteria labeled with different radioactive isotopes, the relative association of the 2 bacteria pumped through the same piece of gut was determined. Cross-labeling showed that choice of isotope did not affect the association. Salmonella typhimurium 395 MR10 was used as reference and the other bacteria investigated related to it. S. typhimurium MR10 and Escherichia coli O 14 K7, which are relatively lipophilic, showed greater association than S. typhimurium 395 MS and E. coli O 111 K58, which are more hydrophilic. Prolonged incubation of bacteria with the length of intestine in vitro leading to damage of the brush border of the mucosal epithelium enhanced association of the bacteria. Similar physico-chemical surface properties may govern the association of certain enterobacteria to the intestinal mucosa as in phagocytosis.