PDBsum entry 4yms

Protein binding/transport protein

PDB id: 4yms

Contents

Protein chains

240 a.a.

215 a.a.

PDB id:

4yms

Name:

Protein binding/transport protein

Title:

Crystal structure of an amino acid abc transporter

Structure:

Abc-type polar amino acid transport system, atpase component. Chain: j, a. Synonym: nbd. Engineered: yes. Abc-type amino acid transport system, permease component. Chain: d, c. Synonym: tmd. Engineered: yes

Source:

Caldanaerobacter subterraneus subsp. Tengcongensis mb4. Organism_taxid: 273068. Strain: mb4. Gene: glnq, tte0514. Expressed in: escherichia coli. Expression_system_taxid: 562. Gene: artm, tte0513. Expression_system_taxid: 562

Resolution:

2.80Å R-factor: 0.228 R-free: 0.271

Authors:

J.Ge,J.Yu,M.Yang

Key ref:

J.Yu et al. (2015). Structural basis for substrate specificity of an amino acid ABC transporter. Proc Natl Acad Sci U S A, 112, 5243-5248. PubMed id: 25848002 DOI: 10.1073/pnas.1415037112

Date:

07-Mar-15 Release date: 22-Apr-15

Protein chains

Q8RCC2  (Q8RCC2_CALS4) -  ABC-type polar amino acid transport system, ATPase component from Caldanaerobacter subterraneus subsp. tengcongensis (strain DSM 15242 / JCM 11007 / NBRC 100824 / MB4)

Seq: 240 a.a.

Struc: 240 a.a.

Protein chains

Q8RCC3  (Q8RCC3_CALS4) -  ABC-type amino acid transport system, permease component from Caldanaerobacter subterraneus subsp. tengcongensis (strain DSM 15242 / JCM 11007 / NBRC 100824 / MB4)

Seq: 220 a.a.

Struc: 215 a.a.

Enzyme reactions

• Enzyme class: Chains J, A, D, C: E.C.?

DOI no: 10.1073/pnas.1415037112

Proc Natl Acad Sci U S A 112:5243-5248 (2015)

PubMed id: 25848002

Structural basis for substrate specificity of an amino acid ABC transporter.

J.Yu, J.Ge, J.Heuveling, E.Schneider, M.Yang.

ABSTRACT

ATP-binding cassette (ABC) transporters are ubiquitous integral membrane proteins that translocate a variety of substrates, ranging from ions to macromolecules, either out of or into the cytosol (hence defined as importers or exporters, respectively). It has been demonstrated that ABC exporters and importers function through a common mechanism involving conformational switches between inward-facing and outward-facing states; however, the mechanism underlying their functions, particularly substrate recognition, remains elusive. Here we report the structures of an amino acid ABC importer Art(QN)2 from Thermoanaerobacter tengcongensis composed of homodimers each of the transmembrane domain ArtQ and the nucleotide-binding domain ArtN, either in its apo form or in complex with substrates (Arg, His) and/or ATPs. The structures reveal that the straddling of the TMDs around the twofold axis forms a substrate translocation pathway across the membrane. Interestingly, each TMD has a negatively charged pocket that together create a negatively charged internal tunnel allowing amino acids carrying positively charged groups to pass through. Our structural and functional studies provide a better understanding of how ABC transporters select and translocate their substrates.