Summary Aerobic neutrophilic Fe‐oxidizing bacteria (FeOB) thrive where oxic and iron‐rich anoxic waters meet. Here, iron microbial mats are commonly developed by stalk‐forming Fe‐oxidizers adapted to these iron‐rich gradient environments, somehow avoiding iron encrustation. Few details are known about FeOB physiology; thus, the bases of these adaptations, notably the mechanisms of interactions with iron, are poorly understood....