4YMW

Crystal structure of an amino acid ABC transporter with histidines

Summary for 4YMW

• Entry DOI: 10.2210/pdb4ymw/pdb
• Related: 4YMS 4YMT 4YMU 4YMV 4YMX
• Descriptor: ABC-type polar amino acid transport system, ATPase component, ABC-type amino acid transport system, permease component, HISTIDINE (3 entities in total)
• Functional Keywords: abc transporter, two binding sites, substrate specificity, membrane protein complex, protein binding-transport protein complex, protein binding/transport protein
• Biological source: Caldanaerobacter subterraneus subsp. tengcongensis MB4; More
• Cellular location: Membrane ; Multi-pass membrane protein : Q8RCC3
• Total number of polymer chains: 4
• Total formula weight: 102445.52

Authors

Ge, J.,Yu, J.,Yang, M. (deposition date: 2015-03-07, release date: 2015-04-22, Last modification date: 2023-11-08)

Primary citation

Yu, J.,Ge, J.,Heuveling, J.,Schneider, E.,Yang, M.
Structural basis for substrate specificity of an amino acid ABC transporter
Proc.Natl.Acad.Sci.USA, 112:5243-5248, 2015

PubMed 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.

PubMed: 25848002
DOI: 10.1073/pnas.1415037112

Experimental method

X-RAY DIFFRACTION (2.804 Å)