Neutrophil gelatinase-associated lipocalin expresses antimicrobial activity by interfering with L-norepinephrine-mediated bacterial iron acquisition.

ABSTRACT: l-norepinephrine (NE) is a neuroendocrine catecholamine that supports bacterial growth by mobilizing iron from a primary source such as holotransferrin to increase its bioavailability for cellular uptake. Iron complexes of NE resemble those of bacterial siderophores that are scavenged by human neutrophil gelatinase-associated lipocalin (NGAL) as part of the innate immune defense. Here, we show that NGAL binds iron-complexed NE, indicating physiological relevance for both bacterial and human iron metabolism. The fluorescence titration of purified recombinant NGAL with the Fe(III).(NE)(3) iron complex revealed high affinity for this ligand, with a K(D) of 50.6 nM. In contrast, the binding protein FeuA of Bacillus subtilis, which is involved in the bacterial uptake of triscatecholate iron com

SUBMITTER: Miethke M 

PROVIDER: S-EPMC2849382 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature