title: Structure of a single-chain Fv fragment of an antibody that inhibits the HIV-1 and HIV-2 proteases.
abstract: The monoclonal antibody 1696, which was raised against the HIV-1 protease, inhibits the catalytic activity of the enzyme from both the HIV-1 and HIV-2 strains. The antibody cross-reacts with peptides containing the N-terminus of the enzyme, which is highly conserved between these strains. The crystal structure of a single-chain Fv fragment of 1696 (scFv-1696) in the non-complexed form, solved at 1.7 A resolution, is compared with the previously reported non-complexed Fab-1696 and antigen-bound scFv-1696 structures. Large conformational changes in the third hypervariable region of the heavy chain and differences in relative orientation of the variable domains are observed between the different structures.
authors.affiliation: European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Lescar
authors.forename: Jiri
authors.initials: J
authors.lastname: Brynda
authors.forename: Milan
authors.initials: M
authors.lastname: Fabry
authors.forename: Magda
authors.initials: M
authors.lastname: Horejsi
authors.forename: Pavlina
authors.initials: P
authors.lastname: Rezacova
authors.forename: Juraj
authors.initials: J
authors.lastname: Sedlacek
authors.forename: Graham A
authors.initials: GA
authors.lastname: Bentley
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry; D000941:Antigens / Q000378:metabolism; D016282:Aspartic Acid Endopeptidases / Q000037:antagonists & inhibitors / Q000276:immunology / Q000378:metabolism; D001665:Binding Sites; D018360:Crystallography, X-Ray; D016333:HIV Protease / Q000276:immunology / Q000378:metabolism; D017320:HIV Protease Inhibitors / Q000737:chemistry*; D015497:HIV-1 / Q000737:chemistry; D006860:Hydrogen Bonding; D007140:Immunoglobulin Fab Fragments / Q000737:chemistry; D007135:Immunoglobulin Variable Region / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D008958:Models, Molecular; D055672:Static Electricity
chemical_list: D000911:Antibodies, Monoclonal; D000941:Antigens; D017320:HIV Protease Inhibitors; D007140:Immunoglobulin Fab Fragments; D007135:Immunoglobulin Variable Region; D016282:Aspartic Acid Endopeptidases; D016333:HIV Protease; C065184:p16 protease, Human immunodeficiency virus 2