title: Crystallization of bi-functional ligand protein complexes.
abstract: Homodimerization is important in signal transduction and can play a crucial role in many other biological systems. To obtaining structural information for the design of molecules able to control the signalization pathways, the proteins involved will have to be crystallized in complex with ligands that induce dimerization. Bi-functional drugs have been generated by linking two ligands together chemically and the relative crystallizability of complexes with mono-functional and bi-functional ligands has been evaluated. There are problems associated with crystallization with such ligands, but overall, the advantages appear to be greater than the drawbacks. The study involves two matrix metalloproteinases, MMP-12 and MMP-9. Using flexible and rigid linkers we show that it is possible to control the crystal packing and that by changing the ligand-enzyme stoichiometric ratio, one can toggle between having one bi-functional ligand binding to two enzymes and having the same ligand bound to each enzyme. The nature of linker and its point of attachment on the ligand can be varied to aid crystallization, and such variations can also provide valuable structural information about the interactions made by the linker with the protein. We report here the crystallization and structure determination of seven ligand-dimerized complexes. These results suggest that the use of bi-functional drugs can be extended beyond the realm of protein dimerization to include all drug design projects.
authors.affiliation: CEA, iBiTec-S, Service d'Ingénierie Moléculaire des Protéines-SIMOPRO, Gif-sur-Yvette F-91191, France. antoni.claudia@cea.fr
authors.forename: Claudia
authors.initials: C
authors.lastname: Antoni
authors.forename: Laura
authors.initials: L
authors.lastname: Vera
authors.forename: Laurent
authors.initials: L
authors.lastname: Devel
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Catalani
authors.forename: Bertrand
authors.initials: B
authors.lastname: Czarny
authors.forename: Evelyn
authors.initials: E
authors.lastname: Cassar-Lajeunesse
authors.forename: Elisa
authors.initials: E
authors.lastname: Nuti
authors.forename: Armando
authors.initials: A
authors.lastname: Rossello
authors.forename: Vincent
authors.initials: V
authors.lastname: Dive
authors.forename: Enrico Adriano
authors.initials: EA
authors.lastname: Stura
mesh_terms: D001665:Binding Sites; D003460:Crystallization; D018360:Crystallography, X-Ray; D019281:Dimerization; D015195:Drug Design; D006801:Humans; D008024:Ligands; D053508:Matrix Metalloproteinase 12 / Q000737:chemistry* / Q000235:genetics; D020780:Matrix Metalloproteinase 9 / Q000737:chemistry* / Q000235:genetics; D046912:Multiprotein Complexes / Q000737:chemistry*; D011485:Protein Binding; D011487:Protein Conformation; D055503:Protein Multimerization
chemical_list: D008024:Ligands; D046912:Multiprotein Complexes; D020780:Matrix Metalloproteinase 9; D053508:Matrix Metalloproteinase 12