3TGO

Crystal structure of the E. coli BamCD complex

Summary for 3TGO

• Entry DOI: 10.2210/pdb3tgo/pdb
• Related: 2LAF 2YH6 2YHC 3QKY 3SNS
• Descriptor: UPF0169 lipoprotein yfiO, Lipoprotein 34, POTASSIUM ION, ... (8 entities in total)
• Functional Keywords: lipoprotein complex, tpr repeat, helix-grip fold, outer membrane protein assembly, outer membrane, membrane protein
• Biological source: Escherichia coli; More
• Cellular location: Cell outer membrane; Lipid-anchor (Potential): P0AC02; Cell outer membrane; Lipid-anchor: P0A903
• Total number of polymer chains: 4
• Total formula weight: 122238.35

Authors

Paetzel, M.,Kim, K.H.,Aulakh, S. (deposition date: 2011-08-17, release date: 2011-09-28, Last modification date: 2023-09-13)

Primary citation

Kim, K.H.,Aulakh, S.,Paetzel, M.
Crystal structure of the beta-barrel assembly machinery BamCD protein complex
J.Biol.Chem., 286:39116-39121, 2011

PubMed Abstract: The β-barrel assembly machinery (BAM) complex of Escherichia coli is a multiprotein machine that catalyzes the essential process of assembling outer membrane proteins. The BAM complex consists of five proteins: one membrane protein, BamA, and four lipoproteins, BamB, BamC, BamD, and BamE. Here, we report the first crystal structure of a Bam lipoprotein complex: the essential lipoprotein BamD in complex with the N-terminal half of BamC (BamC(UN) (Asp(28)-Ala(217)), a 73-residue-long unstructured region followed by the N-terminal domain). The BamCD complex is stabilized predominantly by various hydrogen bonds and salt bridges formed between BamD and the N-terminal unstructured region of BamC. Sequence and molecular surface analyses revealed that many of the conserved residues in both proteins are found at the BamC-BamD interface. A series of truncation mutagenesis and analytical gel filtration chromatography experiments confirmed that the unstructured region of BamC is essential for stabilizing the BamCD complex structure. The unstructured N terminus of BamC interacts with the proposed substrate-binding pocket of BamD, suggesting that this region of BamC may play a regulatory role in outer membrane protein biogenesis.

PubMed: 21937441
DOI: 10.1074/jbc.M111.298166

Experimental method

X-RAY DIFFRACTION (2.9 Å)