PMID: 12453412 , Related PDB id: 1L6M

Authors:

Goetz DH, Holmes MA, Borregaard N, Bluhm ME, Raymond KN, Strong RK

Title:

The neutrophil lipocalin NGAL is a bacteriostatic agent that interferes with siderophore-mediated iron acquisition.

Journal:

Mol Cell. 2002 Nov;10(5):1033-43.

Abstract:

First identified as a neutrophil granule component, neutrophil gelatinase-associated lipocalin (NGAL; also called human neutrophil lipocalin, 24p3, uterocalin, or neu-related lipocalin) is a member of the lipocalin family of binding proteins. Putative NGAL ligands, including neutrophil chemotactic agents such as N-formylated tripeptides, have all been refuted by recent biochemical and structural results. NGAL has subsequently been implicated in diverse cellular processes, but without a characterized ligand, the molecular basis of these functions remained mysterious. Here we report that NGAL tightly binds bacterial catecholate-type ferric siderophores through a cyclically permuted, hybrid electrostatic/cation-pi interaction and is a potent bacteriostatic agent in iron-limiting conditions. We therefore propose that NGAL participates in the antibacterial iron depletion strategy of the innate immune system.