4ZIR

Crystal structure of EcfAA' heterodimer bound to AMPPNP

Summary for 4ZIR

• Entry DOI: 10.2210/pdb4zir/pdb
• Related: 4HLU
• Descriptor: Energy-coupling factor transporter ATP-binding protein EcfA2, Energy-coupling factor transporter ATP-binding protein EcfA1, MAGNESIUM ION, ... (6 entities in total)
• Functional Keywords: atpase, transmembrane transport, vitamin uptake, abc transporter, transport protein, hydrolase-inhibitor complex, hydrolase/inhibitor
• Biological source: Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099); More
• Total number of polymer chains: 2
• Total formula weight: 61360.36

Authors

Karpowich, N.K.,Cocco, N.,Song, J.M.,Wang, D.N. (deposition date: 2015-04-28, release date: 2015-06-10, Last modification date: 2024-11-13)

Primary citation

Karpowich, N.K.,Song, J.M.,Cocco, N.,Wang, D.N.
ATP binding drives substrate capture in an ECF transporter by a release-and-catch mechanism.
Nat.Struct.Mol.Biol., 22:565-571, 2015

PubMed Abstract: ECF transporters are a family of active transporters for vitamins. They are composed of four subunits: a membrane-embedded substrate-binding subunit (EcfS), a transmembrane coupling subunit (EcfT) and two ATP-binding-cassette ATPases (EcfA and EcfA'). We have investigated the mechanism of the ECF transporter for riboflavin from the pathogen Listeria monocytogenes, LmECF-RibU. Using structural and biochemical approaches, we found that ATP binding to the EcfAA' ATPases drives a conformational change that dissociates the S subunit from the EcfAA'T ECF module. Upon release from the ECF module, the RibU S subunit then binds the riboflavin transport substrate. We also find that S subunits for distinct substrates compete for the ATP-bound state of the ECF module. Our results explain how ECF transporters capture the transport substrate and reproduce the in vivo observations on S-subunit competition for which the family was named.

PubMed: 26052893
DOI: 10.1038/nsmb.3040

Experimental method

X-RAY DIFFRACTION (3 Å)