3KWV

Structural basis for the unfolding of anthrax lethal factor by protective antigen oligomers

Summary for 3KWV

• Entry DOI: 10.2210/pdb3kwv/pdb
• Descriptor: Protective antigen PA-63, Lethal factor, CALCIUM ION, ... (4 entities in total)
• Functional Keywords: bacillus anthracis, protective antigen, lethal factor, lethal toxin, octamer, protein transport, toxin, protein unfolding, protein translocation, cleavage on pair of basic residues, metal-binding, secreted, virulence, hydrolase, metalloprotease, protease, toxin-protein transport complex, toxin/protein transport
• Biological source: Bacillus anthracis; More
• Cellular location: Secreted, extracellular space: P13423; Secreted: P15917
• Total number of polymer chains: 6
• Total formula weight: 307350.72

Authors

Feld, G.K.,Kintzer, A.F.,Krantz, B.A. (deposition date: 2009-12-01, release date: 2010-11-10, Last modification date: 2023-09-06)

Primary citation

Feld, G.K.,Thoren, K.L.,Kintzer, A.F.,Sterling, H.J.,Tang, I.I.,Greenberg, S.G.,Williams, E.R.,Krantz, B.A.
Structural basis for the unfolding of anthrax lethal factor by protective antigen oligomers.
Nat.Struct.Mol.Biol., 17:1383-1390, 2010

PubMed Abstract: The protein transporter anthrax lethal toxin is composed of protective antigen (PA), a transmembrane translocase, and lethal factor (LF), a cytotoxic enzyme. After its assembly into holotoxin complexes, PA forms an oligomeric channel that unfolds LF and translocates it into the host cell. We report the crystal structure of the core of a lethal toxin complex to 3.1-Å resolution; the structure contains a PA octamer bound to four LF PA-binding domains (LF(N)). The first α-helix and β-strand of each LF(N) unfold and dock into a deep amphipathic cleft on the surface of the PA octamer, which we call the α clamp. The α clamp possesses nonspecific polypeptide binding activity and is functionally relevant to efficient holotoxin assembly, PA octamer formation, and LF unfolding and translocation. This structure provides insight into the mechanism of translocation-coupled protein unfolding.

PubMed: 21037566
DOI: 10.1038/nsmb.1923

Experimental method

X-RAY DIFFRACTION (3.101 Å)