Analyses, by construction of phage growth curves, indicated that the
polysaccharide depolymerase was synthesized by Pseudomonas aeruginosa strains B and BI after
infection with phage 2. The kinetics of biosynthesis of the depolymerase were found to parallel closely the rate of formation of phage-directed virions, and alterations in the experimental conditions of
infection were reflected by alterations in the production of
enzyme.
Infection with other Pseudomonas phages, 84 and 1197, did not result in the synthesis of depolymerase. The
enzyme was not detectable in uninfected cultures, and no evidence was obtained for the existence of inhibitors or activators of
enzyme activity in extracts of uninfected or infected cells. The results of experiments employing
chloramphenicol or an auxotorphic mutant (BI arg(-)) suggested that
protein synthesis de novo was essential for production of the
enzyme. Various mutants of phage 2 (pdp(1),
pdp(2)), which alter the synthesis of the
polysaccharide depolymerase, have been isolated. These experimental results strongly support the role of the phage genome in the synthesis of this
enzyme.