Work

The Iron Tug-of-War between Bacterial Siderophores and Innate Immunity

Year: 2019

Type: review

Abstract: Iron is necessary for the survival of almost all aerobic organisms. In the mammalian host, iron is a required cofactor for the assembly of functional iron-sulfur (Fe-S) cluster proteins, heme-binding proteins and ribonucleotide reductases that regulate various functions, including heme synthesis, oxygen transport and DNA synthesis. However, the bioavailability of iron is low due to its insolubility under aerobic conditions. Moreover, the host coordinates a nutritional immune response to restrict the accessibility of iron against potential pathogens. To counter nutritional immunity, most commensal and pathogenic bacteria synthesize and secrete small iron chelators termed siderophores. Siderophores have potent affinity for iron, which allows them to seize the essential metal from the host iron-binding proteins. To safeguard against iron thievery, the host relies upon the innate immune protein, lipocalin 2 (Lcn2), which could sequester catecholate-type siderophores and thus impede bacterial growth. However, certain bacteria are capable of outmaneuvering the host by either producing "stealth" siderophores or by expressing competitive antagonists that bind Lcn2 in lieu of siderophores. In this review, we summarize the mechanisms underlying the complex iron tug-of-war between host and bacteria with an emphasis on how host innate immunity responds to siderophores.

Source: Journal of Innate Immunity

DOI: 10.1159/000494627

Authors: Rachel Golonka, Beng San Yeoh, Matam Vijay-Kumar

Institutions: University of Toledo, Pennsylvania State University

Language: English

Topic: Iron Metabolism and Disorders

Subfield: Hematology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,590