4K3C

The crystal structure of BamA from Haemophilus ducreyi lacking POTRA domains 1-3

Summary for 4K3C

• Entry DOI: 10.2210/pdb4k3c/pdb
• Related: 4K3B
• Descriptor: Outer membrane protein assembly factor BamA (2 entities in total)
• Functional Keywords: beta-barrel membrane protein, insertase, membrane protein
• Biological source: Haemophilus ducreyi
• Cellular location: Cell outer membrane (By similarity): Q93PM2
• Total number of polymer chains: 1
• Total formula weight: 59427.86

Authors

Noinaj, N.,Lukacik, P.,Chang, H.,Easley, N.,Buchanan, S.K. (deposition date: 2013-04-10, release date: 2013-09-04, Last modification date: 2024-02-28)

Primary citation

Noinaj, N.,Kuszak, A.J.,Gumbart, J.C.,Lukacik, P.,Chang, H.,Easley, N.C.,Lithgow, T.,Buchanan, S.K.
Structural insight into the biogenesis of beta-barrel membrane proteins.
Nature, 501:385-390, 2013

PubMed Abstract: β-barrel membrane proteins are essential for nutrient import, signalling, motility and survival. In Gram-negative bacteria, the β-barrel assembly machinery (BAM) complex is responsible for the biogenesis of β-barrel membrane proteins, with homologous complexes found in mitochondria and chloroplasts. Here we describe the structure of BamA, the central and essential component of the BAM complex, from two species of bacteria: Neisseria gonorrhoeae and Haemophilus ducreyi. BamA consists of a large periplasmic domain attached to a 16-strand transmembrane β-barrel domain. Three structural features shed light on the mechanism by which BamA catalyses β-barrel assembly. First, the interior cavity is accessible in one BamA structure and conformationally closed in the other. Second, an exterior rim of the β-barrel has a distinctly narrowed hydrophobic surface, locally destabilizing the outer membrane. And third, the β-barrel can undergo lateral opening, suggesting a route from the interior cavity in BamA into the outer membrane.

PubMed: 23995689
DOI: 10.1038/nature12521

Experimental method

X-RAY DIFFRACTION (2.913 Å)