Growth of Vibrio anguillarum in salmon intestinal mucus

The physiological changes of Vibrio anguillarum in response to growth in salmon intestinal mucus were investigated, Growth, survival, and changes in protein expression during growth in media supplemented with mucus were compared to growth and starvation in the identical media without mucus. V. anguillarum exhibited a rapid decline in CFU following growth in mucus as the sole carbon source. No such decline was observed in Luria broth with a 2% NaCl concentration, in glucose-minimal broth (3M), or during starvation in a carbon-, nitrogen-, and phosphorus-free salt solution (NSS). The changes in protein expression during growth in mucus were examined by labeling cells with [S-35]methionine and analyzing the labeled proteins by one- and two-dimensional gel electrophoresis and autoradiography. Comparison of [S-35] methionine-labeled proteins from cells with 3M-grown cells and NSS-starved cells revealed four de novo mucus-inducible proteins (Mips). These Mips were localized in the membrane fraction of V. anguillarum. Additionally, at least one other membrane protein was found to have increased expression in response to growth in mucus.