Fig. 1.

General overview of mechanisms of trace metal homeostasis and utilization by microbiota. Bacteria developed several transport systems for iron, manganese, zinc, and copper absorption. Trace metals alters bacterial survival and fitness by modulating its ability to fight oxidative stress and produce energy via metabolic processes and metal-bound enzymes. ROS = reactive oxygen species; Fe = iron; Mn = manganese; Zn = zinc; Cu = copper; ABC-type = ATP-binding protein; AdcABC/YcdHI = zinc transporter system; ZUR = zinc uptake regulator; PerR = peroxide operon regulator; AdcR = adhesin competence repressor; NRAMP = natural resistance-associated macrophage protein; ZIP = zinc import proteins; CcoA = copper uptake porter; CusABC = copper uptake system; CopZ = copper chaperone.