Brucella abortus siderophore 2,3-dihydroxybenzoic acid protects brucellae from killing by macrophages.

Addition of 2,3-dihydroxybenzoic acid, a siderophore produced by Brucella abortus, to macrophage cultures prevented intracellular killing of brucellae during the first 12 h after infection and increased the number of intracellular brucellae recovered at 48 h after infection. The protective effect could be demonstrated with inflammatory macrophages, interferon-gamma-activated macrophages and with macrophages supplemented with iron, shown elsewhere to facilitate killing of B abortus.