2hh0
Structure of an Anti-PrP Fab, P-Clone, in Complex with its Cognate Bovine Peptide Epitope.
Structural highlights
DiseasePRIO_BOVIN Note=Variations in PRNP are responsible of transmissible bovine spongiform encephalopathies (BSE), a class of neurodegenerative diseases that affect various mammals. These diseases are caused by abnormally folded prion proteins. BSE can be subdivided into at least three groups: classical, H-type and L-type, with the latter 2 collectively referred to as atypical BSE. Susceptibility or resistance to a BSE disease can be influenced by at least 3 factors related to the host prion protein: protein expression levels, number of octapeptide repeats, and specific polymorphisms. In cattle, as in humans, BSEs can occur as infectious, spontaneous and genetic diseases. FunctionPRIO_BOVIN May play a role in neuronal development and synaptic plasticity. May be required for neuronal myelin sheath maintenance. May play a role in iron uptake and iron homeostasis. Soluble oligomers are toxic to cultured neuroblastoma cells and induce apoptosis (in vitro). Association with GPC1 (via its heparan sulfate chains) targets PRNP to lipid rafts. Also provides Cu(2+) or ZN(2+) for the ascorbate-mediated GPC1 deaminase degradation of its heparan sulfate side chains (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 PubMedBovine spongiform encephalopathy (BSE) is a fatal neurodegenerative prion disease affecting cattle that is transmissible to humans, manifesting as a variant of Creutzfeldt-Jakob disease (vCJD) likely following the consumption of meat contaminated with BSE prions. High-affinity antibodies are a prerequisite for the development of simple, highly sensitive and non-invasive diagnostic tests that are able to detect even small amounts of the disease-associated PrP conformer (PrP(Sc)). We describe here the affinity maturation of a single-chain Fv antibody fragment with a binding affinity of 1 pM to a peptide derived from the unstructured region of bovine PrP (BoPrP (90-105)). This is the tightest peptide-binding antibody reported to date and may find useful application in diagnostics, especially when PrP(Sc) is pretreated by denaturation and/or proteolysis for peptide-like presentation. Several rounds of directed evolution and off-rate selection with ribosome display were performed using an antibody library generated from a single PrP binder with error-prone PCR and DNA-shuffling. As the correct determinations of affinities in this range are not straightforward, competition biosensor techniques and KinExA methods were both applied and compared. Structural interpretation of the affinity improvement was performed based on the crystal structure of the original prion binder in complex with the BoPrP (95-104) peptide by modeling the corresponding mutations. Directed evolution of an anti-prion protein scFv fragment to an affinity of 1 pM and its structural interpretation.,Luginbuhl B, Kanyo Z, Jones RM, Fletterick RJ, Prusiner SB, Cohen FE, Williamson RA, Burton DR, Pluckthun A J Mol Biol. 2006 Oct 13;363(1):75-97. Epub 2006 Jul 21. PMID:16962610[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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