8VOW

Cryo-EM structure of the ABC transporter PCAT1 cysteine-free core bound with MgATP and Vi

Summary for 8VOW

• Entry DOI: 10.2210/pdb8vow/pdb
• EMDB information: 43393
• Descriptor: ABC-type bacteriocin transporter, ADENOSINE-5'-TRIPHOSPHATE, MAGNESIUM ION, ... (5 entities in total)
• Functional Keywords: abc transporter, nucleotide, membrane protein, transport protein
• Biological source: Acetivibrio thermocellus ATCC 27405
• Total number of polymer chains: 2
• Total formula weight: 135253.90

Authors

Zhang, R.,Jagessar, K.L.,Polasa, A.,Brownd, M.,Stein, R.,Moradi, M.,Karakas, E.,Mchaourab, H.S. (deposition date: 2024-01-16, release date: 2024-10-30)

Primary citation

Zhang, R.,Jagessar, K.L.,Brownd, M.,Polasa, A.,Stein, R.A.,Moradi, M.,Karakas, E.,Mchaourab, H.S.
Conformational cycle of a protease-containing ABC transporter in lipid nanodiscs reveals the mechanism of cargo-protein coupling.
Nat Commun, 15:9055-9055, 2024

PubMed Abstract: Protease-containing ABC transporters (PCATs) couple the energy of ATP hydrolysis to the processing and export of diverse cargo proteins across cell membranes to mediate antimicrobial resistance and quorum sensing. Here, we combine biochemical analysis, single particle cryoEM, and DEER spectroscopy in lipid bilayers along with computational analysis to illuminate the structural and energetic underpinnings of coupled cargo protein export. Our integrated investigation uncovers competitive interplay between nucleotides and cargo protein binding that ensures the latter's orderly processing and subsequent transport. The energetics of cryoEM structures in lipid bilayers are congruent with the inferred mechanism from ATP turnover analysis and reveal a snapshot of a high-energy outward-facing conformation that provides an exit pathway into the lipid bilayer and/or the extracellular side. DEER investigation of the core ABC transporter suggests evolutionary tuning of the energetic landscape to fulfill the function of substrate processing prior to export.

PubMed: 39428489
DOI: 10.1038/s41467-024-53420-0

Experimental method

ELECTRON MICROSCOPY (3.44 Å)