Restoration of phage susceptibility as a result of trans-complementation of Y. pestis LPS-affected mutants.

aThe phage plaquing tests were performed at 28°C.b+, phage-susceptible; −, phage-resistant.cEach of the mutants was also transformed with a pBAD vector without insert to exclude possible impact of the vector on LPS structure and phage susceptibility; all pBAD+ transformants had the same phenotype as the parental mutant (data not shown).dSee characteristics of the recombinant plasmids in Table 1 and Materials and Methods.