PDBsum entry 4zir

Transport protein, hydrolase/inhibitor

PDB id: 4zir

Contents

Protein chains

263 a.a.

247 a.a.

Ligands

ANP ×2

Metals

_MG ×2

_CL ×3

Waters ×20

PDB id:

4zir

Name:

Transport protein, hydrolase/inhibitor

Title:

Crystal structure of ecfaa' heterodimer bound to amppnp

Structure:

Energy-coupling factor transporter atp-binding protein ecfa2. Chain: a. Synonym: ecf transporter a component ecfa2, tmecfa. Engineered: yes. Energy-coupling factor transporter atp-binding protein ecfa1. Chain: b. Synonym: ecf transporter a component ecfa1, tmecfa'.

Source:

Thermotoga maritima (strain atcc 43589 / msb8 / dsm 3109 / jcm 10099). Organism_taxid: 243274. Strain: atcc 43589 / msb8 / dsm 3109 / jcm 10099. Gene: ecfa2, ecfa, ecfa', tm_0222. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008. Gene: ecfa1, cbio, ecfa', tm_1663.

Resolution:

3.00Å R-factor: 0.198 R-free: 0.247

Authors:

N.K.Karpowich,N.Cocco,J.M.Song,D.N.Wang

Key ref:

N.K.Karpowich et al. (2015). ATP binding drives substrate capture in an ECF transporter by a release-and-catch mechanism. Nat Struct Biol, 22, 565-571. PubMed id: 26052893 DOI: 10.1038/nsmb.3040

Date:

28-Apr-15 Release date: 10-Jun-15

Protein chain

Q9WY65  (ECFA2_THEMA) -  Energy-coupling factor transporter ATP-binding protein EcfA2 from Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8)

Seq: 266 a.a.

Struc: 263 a.a.*

Protein chain

Q9X1Z1  (ECFA1_THEMA) -  Energy-coupling factor transporter ATP-binding protein EcfA1 from Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8)

Seq: 259 a.a.

Struc: 247 a.a.*

* PDB and UniProt seqs differ at 9 residue positions (black crosses)

Enzyme reactions

• Enzyme class: Chains A, B: E.C.7.-.-.-

DOI no: 10.1038/nsmb.3040

Nat Struct Biol 22:565-571 (2015)

PubMed id: 26052893

ATP binding drives substrate capture in an ECF transporter by a release-and-catch mechanism.

N.K.Karpowich, J.M.Song, N.Cocco, D.N.Wang.

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.