Exploring Iron Withholding by the Innate Immune Protein Human Calprotectin
Abstract
Calprotectin (CP) is a versatile player in the metal-withholding innate immune response, a process termed "nutritional immunity." CP is a heterooligomer of the polypeptides S100A8 and S100A9 and houses two transition-metal-binding sites at its S100A8/S100A9 heterodimer interface. During infection, CP is released from host cells and sequesters "bioavailable" transition metal ions in the extracellular space, thereby preventing microbial acquisition of these essential nutrients. For many years, the role of CP in nutritional immunity was interpreted in the contexts of Mn(II) and Zn(II) limitation, but recent work has broadened our understanding of its contributions to this process. We uncovered that CP provides a form of nutritional immunity that has previously received little attention: the battle between host and microbe for ferrous iron (Fe(II)). In this Account, we present our current understanding of Fe(II) coordination by CP and its role in Fe(II) withholding as well as considerations for future discovery. Nutritional immunity was first described in the context of host-microbe competition for ferric iron (Fe(III)). The battle for Fe(II) has received comparably little attention because the abundance of Fe(II) at infection site...Continue Reading
References
Citations
Manganese Uptake, Mediated by SloABC and MntH, Is Essential for the Fitness of Streptococcus mutans.
Related Concepts
Related Feeds
Birth Defects
Birth defects encompass structural and functional alterations that occur during embryonic or fetal development and are present since birth. The cause may be genetic, environmental or unknown and can result in physical and/or mental impairment. Here is the latest research on birth defects.
Acinetobacter Infections
Acinetobacter infections have become common in hospitalized patients, especially in the intensive care unit setting and are difficult to treat due to their propensity to develop antimicrobial drug resistance. Discover the latest research on Acinetobacter Infections here.