PDBsum entry 4u4x

Membrane protein

PDB id: 4u4x

Contents

Protein chains

263 a.a.

Ligands

3C2 ×2

SO4 ×5

GLU ×2

ACT ×4

GOL ×3

PEG ×2

Waters ×590

PDB id:

4u4x

Name:

Membrane protein

Title:

Crystal structure of the glua2 ligand-binding domain (s1s2j-l483y- n754s) in complex with glutamate and bpam37 at 1.56 a resolution.

Structure:

Glutamate receptor 2,glutamate receptor 2. Chain: a, b. Fragment: unp residues 413-527, unp residues 653-796. Synonym: ampa 2,glua2. Engineered: yes. Mutation: yes

Source:

Rattus norvegicus. Rat. Organism_taxid: 10116. Gene: gria2, glur2. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008.

Resolution:

1.56Å R-factor: 0.151 R-free: 0.175

Authors:

A.B.Noerholm,K.Frydenvang,J.S.Kastrup

Key ref:

P.Francotte et al. (2014). Positive allosteric modulators of 2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid receptors belonging to 4-cyclopropyl-3,4-dihydro-2h-1,2,4-pyridothiadiazine dioxides and diversely chloro-substituted 4-cyclopropyl-3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxides. J Med Chem, 57, 9539-9553. PubMed id: 25375781 DOI: 10.1021/jm501268r

Date:

24-Jul-14 Release date: 19-Nov-14

Protein chains

P19491  (GRIA2_RAT) -  Glutamate receptor 2 from Rattus norvegicus

Seq: 883 a.a.

Struc: 263 a.a.*

* PDB and UniProt seqs differ at 6 residue positions (black crosses)

DOI no: 10.1021/jm501268r

J Med Chem 57:9539-9553 (2014)

PubMed id: 25375781

Positive allosteric modulators of 2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid receptors belonging to 4-cyclopropyl-3,4-dihydro-2h-1,2,4-pyridothiadiazine dioxides and diversely chloro-substituted 4-cyclopropyl-3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxides.

P.Francotte, A.B.Nørholm, T.Deva, L.Olsen, K.Frydenvang, E.Goffin, P.Fraikin, P.de Tullio, S.Challal, J.Y.Thomas, F.Iop, C.Louis, I.Botez-Pop, P.Lestage, L.Danober, J.S.Kastrup, B.Pirotte.

ABSTRACT

Two 4-ethyl-substituted pyridothiadiazine dioxides belonging to α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor positive allosteric modulators were cocrystallized with the GluA2 ligand binding domain in order to decipher the impact of the position of the nitrogen atom on their binding mode at the AMPA receptors. The latter was found to be very similar to that of previously described benzothiadiazine-type AMPA receptor modulators. The affinity of the two compounds for the receptor was determined by isothermal titration calorimetry. Accordingly, the synthesis and biological evaluation of novel 4-cyclopropyl-substituted pyridothiadiazine dioxides was performed and completed with the synthesis of the corresponding chloro-substituted 4-cyclopropyl-3,4-dihydro-2H-benzothiadiazine 1,1-dioxides. The "8-aza" compound 32 was found to be the most potent pyridothiadiazine-type AMPA receptor potentiator in vitro, whereas the 7-chloro-substituted compound 36c emerged as the most promising benzothiadiazine dioxide. Due to proper drug-likeness and low in vivo acute toxicity in mice, 36c was chosen for a more complete preclinical evaluation. The compound was able to easily cross the blood-brain barrier. In an in vivo object recognition test with CD1 mice, oral administration of 36c was found to significantly improve cognition performance at doses as low as 1 mg/kg.