Diaminopimelic Acid and Lysine Auxotrophs of Pseudomonas aeruginosa 8602

SUMMARY: Lysine auxotrophs have been isolated from Pseudomonas aeruginosa 8602. Three of the mutants were deficient in diaminopimelate decarboxylase and accumulated meso- and ll-diaminopimelic acid (DAP) but otherwise were indistinguishable from the parent strain. The fourth mutant required lysine for optimal growth, grew slowly on meso- but not ll-DAP, and the DAP which accumulated in large amounts was solely the ll-isomer. This mutant was deficient in diaminopimelate epimerase. No significant differences were detected between its wall composition and that of the parent strain but it was particularly sensitive to carbenicillin.