Carboxymycobactin gets secreted Loaded mycobactin gets imported Iron is reduced and separates from mycobactin BfrA stores iron BfrB stores iron Mycobactin is exported Carboxymycobactin and mycobactin exchange their iron load Mtb iron assimilation by chelation Authored: Stephan, R, 2011-01-10 Edited: Jassal, B, 2011-02-28 GENE ONTOLOGYGO:0033214 Pubmed17804665 Reactome Database ID Release 431222449 Reactome, http://www.reactome.org ReactomeREACT_121118 Reviewed: Warner, D, 2012-04-30 Uptake of iron in <i>Mtb</i>, especially when the bacterium is in the host, strongly depends on siderophores. Humans, through secretion of lactoferrin, maintain an iron concentration of 10^(-18) M within macrophages, and the bacterium has evolved the siderophores mycobactin T and exomycobactin T (formerly exochelin) to cope with this shortage. While nonpolar mycobactin T stays in the cell wall and only moves around in liquid droplets, polar exochelin is abundantly secreted. As it can bind iron with higher affinity than lactoferrin, it frequently scavenges iron ions from this molecule (Miethke & Marahiel 2007). Carboxymycobactin binds iron from lactoferrin PathwayStep3811 PathwayStep3812 PathwayStep3810 PathwayStep3805 PathwayStep3807 PathwayStep3806 PathwayStep3809 PathwayStep3808