Growth in mouse peritoneal macrophages of Yersinia pestis lacking established virulence determinants

摘要: Cultured mouse resident peritoneal macrophages were challenged with strains of Yersinia pestis differing only respect to the absence one or more virulence determinants established for species. Guanine-auxotrophic (Pur-) yersiniae unable survive within macrophages; exogenous hypoxanthine and guanosine permitted intracellular growth. This finding supports idea that Pur- are avirulent due inability obtain sufficient free purines in host tissues growth maintenance indicates net biosynthesis is necessary counteract microbicidal environment macrophages. Yersiniae pigment medium containing dye Congo red (Pgm-) lacking either plasmids associated pesticin calcium dependence (Pst- Vwa-, respectively) taken up as efficiently into grew well these cells did bacteria having all invasive intact. Opsonization 100% homologous normal serum before infection not affect ability Pgm- Vwa- grow Accordingly, attributes independent mediate survival macrophages, components mammalian other than must interact Pgm-, Pst- cause their avirulence vivo.