The ligand-binding domain in metabotropic glutamate receptors is related to bacterial periplasmic binding proteins

Neuron. 1993 Jul;11(1):41-52. doi: 10.1016/0896-6273(93)90269-w.


Receptors for the major excitatory neurotransmitter glutamate include metabotropic (G protein-coupled) and ionotropic (glutamate-gated ion channel) types. These receptors have large, presumably extracellular, amino-terminal domains. Sensitive sequence analysis techniques indicate that the metabotropic receptor extracellular domain is similar to bacterial periplasmic amino acid binding proteins. A structural model built using the observed similarity predicts a ligand-binding site, and mutants with conservative amino acid substitutions at this site are shown to have reduced ligand affinity. The metabotropic receptor extracellular domain is a member of a family of structural domains linked to a variety of receptor types, including ionotropic glutamate receptors.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism*
  • Binding Sites
  • Carrier Proteins / genetics*
  • Carrier Proteins / metabolism*
  • Databases, Factual
  • Forecasting
  • Ligands
  • Models, Molecular
  • Molecular Sequence Data
  • Receptors, Glutamate / genetics*
  • Receptors, Glutamate / metabolism*
  • Sequence Homology, Amino Acid


  • Bacterial Proteins
  • Carrier Proteins
  • Ligands
  • Receptors, Glutamate

Associated data

  • GENBANK/M38060
  • GENBANK/M90518
  • GENBANK/X58820
  • GENBANK/X64421