CHEMOTAXIS TO OLIGOPEPTIDES BY PSEUDOMONAS-AERUGINOSA

A number of peptides were evaluated as chemoattractants for Pseudomona s aeruginosa. Several strains recognized tri-, tetra-, penta-, and hex apeptides in a capillary tube assay. Tripeptides altered at the carbox yl terminus were good attractants, whereas tripeptides altered at the amino terminus did not serve as chemoattractants. Methionine-containin g peptides were relatively poor attractants. Arginine-containing pepti des gave the best responses. Reduced responses to larger peptides sugg est that porin penetration is required. No extracellular peptidase act ivity was detected. We conclude that oligopeptides are good attractant s and that specificity for chemotactic recognition of oligopeptides ex ists.