Download MendeleyCrystal structure of bacterial haem importer complex in the inward-facing conformation
Naoe, Y., Nakamura, N., Doi, A., Sawabe, M., Nakamura, H., Shiro, Y., Sugimoto, H.(2016) Nat Commun 7: 13411-13411
- PubMed: 27830695
- DOI: https://doi.org/10.1038/ncomms13411
- Primary Citation of Related Structures:
5B57, 5B58 - PubMed Abstract:
Pathogenic bacteria remove iron from the haem of host tissues and use it as a catalytic center of many enzymes. Haem uptake by pathogenic bacteria is facilitated by the membrane-integrated haem importer, which belongs to the type II ATP-binding cassette (ABC) transporter. Here we present crystal structures of Burkholderia cenocepacia haem importer BhuUV complexed with the periplasmic haem-binding protein BhuT and in the absence of BhuT. The transmembrane helices of these structures show an inward-facing conformation, in which the cytoplasmic gate of the haem translocation pathway is completely open. Since this conformation is found in both the haem- and nucleotide-free form, the structure of BhuUV-T provides the post-translocation state and the missing piece in the transport cycle of the type II importer. Structural comparison with the outward-facing conformation reported for the haem importer ortholog HmuUV from Yersenia pestis gives mechanistic insights into conformational transitions and haem secretion during the haem transport cycle.
Organizational Affiliation:
Biometal Science Laboratory, RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan.
