Abstract:Iron is a key element that influences microbial growth and metabolism by binding to proteins and acting as a catalyst, redox or regulator. The growth metabolism of anaerobic ammonium-oxidizing (ANAMMOX) bacteria is highly dependent on iron, especially iron-containing proteins. The anaerobic lifestyle of ANAMMOX bacteria and the presence of anammoxosome make their pattern of iron metabolism different from that of other microorganisms. Clarification of the pattern of iron uptake metabolism of ANAMMOX bacteria could provide the basis for obtaining their pure cultures and facilitate their application in the environmental field. Here, we combine existing views on iron uptake, utilization, and metabolism with genomic information and limited biochemical and physiological data of ANAMMOX bacteria to propose possible iron utilization pathways of ANAMMOX bacteria for subsequent physiochemical and biochemical studies.