1qgc
STRUCTURE OF THE COMPLEX OF A FAB FRAGMENT OF A NEUTRALIZING ANTIBODY WITH FOOT AND MOUTH DISEASE VIRUSSTRUCTURE OF THE COMPLEX OF A FAB FRAGMENT OF A NEUTRALIZING ANTIBODY WITH FOOT AND MOUTH DISEASE VIRUS
Structural highlights
FunctionPOLG_FMDVS The leader protease autocatalytically cleaves itself from the polyprotein at the L/VP0 junction. It cleaves the host translation initiation factors EIF4G1 and EIF4G3, in order to shut down the capped cellular mRNA transcription (By similarity). Capsid proteins VP1, VP2, VP3 and VP4 form a closed capsid enclosing the viral positive strand RNA genome. VP4 lies on the inner surface of the protein shell formed by VP1, VP2 and VP3. All the three latter proteins contain a beta-sheet structure called beta-barrel jelly roll. Together they form an icosahedral capsid (T=3) composed of 60 copies of each VP1, VP2, and VP3, with a diameter of approximately 300 Angstroms. VP1 is situated at the 12 fivefold axes, whereas VP2 and VP3 are located at the quasi-sixfold axes. The capsid interacts with host heparan sulfate and various integrins (alphavbeta1, alphavbeta3, alpha5beta1, alphavbeta6, alphavbeta8) to provide virion attachment to target Attachment via host integrins induces virion internalization predominantly through clathrin-mediated endocytosis (By similarity). Protein VP0: VP0 precursor is a component of immature procapsids (By similarity). Protein 2B: Affects membrane integrity and cause an increase in membrane permeability (By similarity). Protein 2C: Associates with and induces structural rearrangements of intracellular membranes. It displays RNA-binding, nucleotide binding and NTPase activities (By similarity). Protein 3A, via its hydrophobic domain, serves as membrane anchor (By similarity). Protein 3B-1, 3B-2 and 3B-3 are covalently linked to the 5'-end of both the positive-strand and negative-strand genomic RNAs. They acts as a genome-linked replication primer (By similarity). Protease 3C: cysteine protease that generates mature viral proteins from the precursor polyprotein. In addition to its proteolytic activity, it binds to viral RNA, and thus influences viral genome replication. RNA and substrate bind cooperatively to the protease (By similarity). RNA-directed RNA polymerase 3D-POL replicates genomic and antigenomic RNA by recognizing replications specific signals (By similarity). Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedData from cryo-electron microscopy and X-ray crystallography have been combined to study the interactions of foot-and-mouth disease virus serotype C (FMDV-C) with a strongly neutralizing monoclonal antibody (mAb) SD6. The mAb SD6 binds to the long flexible GH-loop of viral protein 1 (VP1) which also binds to an integrin receptor. The structure of the virus-Fab complex was determined to 30 A resolution using cryo-electron microscopy and image analysis. The known structure of FMDV-C, and of the SD6 Fab co-crystallized with a synthetic peptide corresponding to the GH-loop of VP1, were fitted to the cryo-electron microscope density map. The SD6 Fab is seen to project almost radially from the viral surface in an orientation which is only compatible with monovalent binding of the mAb. Even taking into account the mAb hinge and elbow flexibility, it is not possible to model bivalent binding without severely distorting the Fabs. The bound GH-loop is essentially in what has previously been termed the 'up' position in the best fit Fab orientation. The SD6 Fab interacts almost exclusively with the GH-loop of VP1, making very few other contacts with the viral capsid. The position and orientation of the SD6 Fab bound to FMDV-C is in accord with previous immunogenic data. Structure of the complex of an Fab fragment of a neutralizing antibody with foot-and-mouth disease virus: positioning of a highly mobile antigenic loop.,Hewat EA, Verdaguer N, Fita I, Blakemore W, Brookes S, King A, Newman J, Domingo E, Mateu MG, Stuart DI EMBO J. 1997 Apr 1;16(7):1492-500. PMID:9130694[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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