1. d-Serine utilization contributes to fitness of P
d-Serine utilization contributes to fitness of P. mirabilis within the bloodstream.
d-Serine utilization contributes to fitness of P. mirabilis within the bloodstream. Proteus mirabilis strain HI4320 (WT, black circles) and the dsdA mutant (open blue circles) were cultured in LB broth overnight, washed once in PBS, and adjusted to 2 × 108 CFU/ml. CBA/J mice (n = 8) were inoculated by tail vein injection of 100 µl containing a 1:1 mixture of dsdA and WT strains. Mice were euthanized at 24 hpi, and bacterial burden was determined in the spleens, livers, and kidneys. (A) Each symbol represents the log10 CFU per gram of tissue from an individual mouse, with the WT and dsdA CFU connected by black lines. Gray bars represent the means, and the dashed line indicates the limit of detection. (B) A competitive index was calculated as described above. Each symbol represents the log10 CI for an individual mouse, error bars represent the medians, and the dashed line indicates log10 CI = 0 (the expected value if the ratio of mutant/WT is 1:1). *, P < 0.05, **, P < 0.01 by Wilcoxon signed-rank test.
Aimee L. Brauer et al. mSphere 2019; doi: /mSphere