FIG 4.

HutH promotes A. baumannii histidine nitrogen source utilization. (A) Growth monitored based on the OD₆₀₀ of WT A. baumannii 17978 and ΔhutH and ΔhutU strains in M9 minimal media with fumarate as the sole carbon source with or without NH₄Cl. (B) Growth monitored based on the OD₆₀₀ of WT A. baumannii 17978 and ΔhutH and ΔhutU strains in M9 minimal media with histidine as the sole carbon source with or without NH₄Cl. (C) Representative growth curve monitored based on the OD₆₀₀ of WT A. baumannii 17978 and ΔhutH and ΔhutU strains in M9 minimal media with fumarate as the sole carbon source and histidine as the sole nitrogen source. (D) Percent growth relative to WT at 15 h for ΔhutH and ΔhutU strains with fumarate as the sole carbon source and histidine as the sole nitrogen source. ****, P < 0.0001 (as determined by Student t test and combined from three independent experiments).