Applications of ribosomal in situ hybridization for the study of bacterial cells in the mouse intestine

Localization of E. coli and S. typhimurium in the large and small intestine of streptomycin-treated mice was visualized by in situ hybridization with specific rRNA target probes and epi-fluorescence microscopy. Growth rates of E. coli BJ4 colonizing the large intestine of streptomycin-treated mice were estimated by quantitative hybridization. The ribosomal contents were measured in bacteria isolated from cecal mucus, cecal contents and feces and correlated with the ribosomal contents of bacteria growing in vitro with defined rates. The data suggest that E. coli BJ4 grows with an apparent doubling time of 40-80 minutes in the intestinal mucosa.