Substrate binding domain of the arginine-, lysine-, histidine-binding protein ArtJ; the type 2 periplasmic binding protein fold
This group includes the periplasmic substrate-binding protein ArtJ of the ATP-binding cassette (ABC) transport system from the thermophilic bacterium Geobacillus stearothermophilus, which is specific for arginine, lysine, and histidine. ArtJ belongs to the type 2 periplasmic-binding fold protein (PBP2) superfamily, whose members are involved in chemotaxis and uptake of nutrients and other small molecules from the extracellular space as a primary receptor. PBP2 typically comprises of two globular subdomains connected by a flexible hinge and bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two receptor cytoplasmically-located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis.
Feature 1:chemical substrate binding site [chemical binding site]
Evidence:
Structure:2Q2C; the arginine-, lysine-, histidine-binding protein Artj from the thermophilic bacterium Geobacillus stearothermophilus binds histidine, contacts at 4A
Jiyao W et al.(2023). "The conserved domain database in 2023.",