title: Elucidation of binding sites of dual antagonists in the human chemokine receptors CCR2 and CCR5.
abstract: Design of dual antagonists for the chemokine receptors CCR2 and CCR5 will be greatly facilitated by knowledge of the structural differences of their binding sites. Thus, we computationally predicted the binding site of the dual CCR2/CCR5 antagonist N-dimethyl-N-[4-[[[2-(4-methylphenyl)-6,7-dihydro-5H-benzohepten-8-yl] carbonyl]amino]benzyl]tetrahydro-2H-pyran-4-aminium (TAK-779), and a CCR2-specific antagonist N-(carbamoylmethyl)-3-trifluoromethyl benzamido-parachlorobenzyl 3-aminopyrrolidine (Teijin compound 1) in an ensemble of predicted structures of human CCR2 and CCR5. Based on our predictions of the protein-ligand interactions, we examined the activity of the antagonists for cells expressing thirteen mutants of CCR2 and five mutants of CCR5. The results show that residues Trp98(2.60) and Thr292(7.40) contribute significantly to the efficacy of both TAK-779 and Teijin compound 1, whereas His121(3.33) and Ile263(6.55) contribute significantly only to the antagonistic effect of Teijin compound 1 at CCR2. Mutation of residues Trp86(2.60) and Tyr108(3.32) adversely affected the efficacy of TAK-779 in antagonizing CCR5-mediated chemotaxis. Y49A(1.39) and E291A(7.39) mutants of CCR2 showed a complete loss of CCL2 binding and chemotaxis, despite robust cell surface expression, suggesting that these residues are critical in maintaining the correct receptor architecture. Modeling studies support the hypothesis that the residues Tyr49(1.39), Trp98(2.60), Tyr120(3.32), and Glu291(7.39) of CCR2 form a tight network of aromatic cluster and polar contacts between transmembrane helices 1, 2, 3, and 7.
authors.affiliation: Department of Immunology, Beckman Research Institute of the City of Hope, Duarte, California 91010, USA.
authors.forename: Spencer E
authors.initials: SE
authors.lastname: Hall
authors.forename: Allen
authors.initials: A
authors.lastname: Mao
authors.forename: Vicky
authors.initials: V
authors.lastname: Nicolaidou
authors.forename: Mattea
authors.initials: M
authors.lastname: Finelli
authors.forename: Emma L
authors.initials: EL
authors.lastname: Wise
authors.forename: Belinda
authors.initials: B
authors.lastname: Nedjai
authors.forename: Julie
authors.initials: J
authors.lastname: Kanjanapangka
authors.forename: Paymann
authors.initials: P
authors.lastname: Harirchian
authors.forename: Deborah
authors.initials: D
authors.lastname: Chen
authors.forename: Victor
authors.initials: V
authors.lastname: Selchau
authors.forename: Sofia
authors.initials: S
authors.lastname: Ribeiro
authors.forename: Sabine
authors.initials: S
authors.lastname: Schyler
authors.forename: James E
authors.initials: JE
authors.lastname: Pease
authors.forename: Richard
authors.initials: R
authors.lastname: Horuk
authors.forename: Nagarajan
authors.initials: N
authors.lastname: Vaidehi
mesh_terms: D000577:Amides / Q000737:chemistry* / Q000494:pharmacology; D000818:Animals; D001549:Benzamides / Q000737:chemistry* / Q000494:pharmacology; D001665:Binding Sites; D001667:Binding, Competitive; D065100:CCR5 Receptor Antagonists; D045744:Cell Line, Tumor; D002633:Chemotaxis; D006801:Humans; D051379:Mice; D008958:Models, Molecular; D017354:Point Mutation; D011487:Protein Conformation; D011759:Pyrrolidines / Q000737:chemistry* / Q000494:pharmacology; D000644:Quaternary Ammonium Compounds / Q000737:chemistry* / Q000494:pharmacology; D011869:Radioligand Assay; D054390:Receptors, CCR2 / Q000037:antagonists & inhibitors* / Q000737:chemistry* / Q000235:genetics; D019713:Receptors, CCR5 / Q000737:chemistry* / Q000235:genetics
chemical_list: D000577:Amides; D001549:Benzamides; C515334:CCR2 protein, human; D065100:CCR5 Receptor Antagonists; C541285:N-(carbamoylmethyl)-3-trifluoromethyl benzamido-4-chlorobenzyl 3-aminopyrrolidine; D011759:Pyrrolidines; D000644:Quaternary Ammonium Compounds; D054390:Receptors, CCR2; D019713:Receptors, CCR5; C119369:TAK 779