RT Journal Article SR Electronic(1) A1 Schmerk, Crystal L. A1 Duplantis, Barry N. A1 Howard, Perry L. A1 Nano, Francis E.YR 2009 T1 A Francisella novicida pdpA mutant exhibits limited intracellular replication and remains associated with the lysosomal marker LAMP-1 JF Microbiology, VO 155 IS 5 SP 1498 OP 1504 DO https://doi.org/10.1099/mic.0.025445-0 PB Microbiology Society, SN 1465-2080, AB Several genes contained in the Francisella pathogenicity island (FPI) encode proteins needed for intracellular growth and virulence of Francisella tularensis. The pdpA gene is the first cistron in the larger of the two operons found in the FPI. In this work we studied the intracellular growth phenotype of a Francisella novicida mutant in the pdpA gene. The ΔpdpA strain was capable of a small amount of intracellular replication but, unlike wild-type F. novicida, remained associated with the lysosomal marker LAMP-1, suggesting that PdpA is necessary for progression from the early phagosome phase of infection. Strains with in cis complementation of the ΔpdpA lesion showed a restoration of intracellular growth to wild-type levels. Infection of macrophages with the ΔpdpA mutant generated a host-cell mRNA profile distinct from that generated by infection with wild-type F. novicida. The transcriptional response of the host macrophage indicates that PdpA functions directly or indirectly to suppress macrophage ability to signal via growth factors, cytokines and adhesion ligands., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.025445-0