2itf
Crystal structure IsdA NEAT domain from Staphylococcus aureus with heme bound
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OverviewOverview
Successful pathogenic organisms have developed mechanisms to thrive under, extreme levels of iron restriction. Haem-iron represents the largest iron, reservoir in the human body and is a significant source of iron for some, bacterial pathogens. NEAT (NEAr Transporter) domains are found exclusively, in a family of cell surface proteins in Gram-positive bacteria. Many NEAT, domain-containing proteins, including IsdA in Staphylococcus aureus, are, implicated in haem binding. Here, we show that overexpression of IsdA in, S. aureus enhances growth and an inactivation mutant of IsdA has a growth, defect, compared with wild type, when grown in media containing haem as, the sole iron source. Furthermore, the haem-binding property of IsdA is, contained within the NEAT domain. Crystal structures of the apo-IsdA NEAT, domain and in complex with haem were solved and reveal a clathrin, adapter-like beta-sandwich fold with a large hydrophobic haem-binding, pocket. Haem is bound with the propionate groups directed at the molecular, surface and the iron is co-ordinated solely by Tyr(166). The phenol groups, of Tyr(166) and Tyr(170) form an H-bond that may function in regulating, haem binding and release. An analysis of IsdA structure-sequence, alignments indicate that conservation of Tyr(166) is a predictor of haem, binding by NEAT domains.
About this StructureAbout this Structure
2ITF is a Single protein structure of sequence from Staphylococcus aureus with HEM as ligand. Full crystallographic information is available from OCA.
ReferenceReference
Haem recognition by a Staphylococcus aureus NEAT domain., Grigg JC, Vermeiren CL, Heinrichs DE, Murphy ME, Mol Microbiol. 2007 Jan;63(1):139-49. PMID:17229211
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