Binding of recombinant PrP c to human plasminogen: Kinetic and thermodynamic study using a resonant mirror biosensor

Transmissible spongiform encephalopathies are a class of sporadic, genetic and transmissible neurodegenerative diseases that affect both humans and animals. Propagation of these diseases is thought to be due to the misfolding of a neuronal glyco‐protein, PrP c , into a pathological insoluble conform...

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Published in:Proteins, structure, function, and bioinformatics Vol. 58; no. 3; pp. 728 - 734
Main Authors: Cuccioloni, Massimiliano, Amici, Manila, Eleuteri, Anna Maria, Biagetti, Massimo, Barocci, Simone, Angeletti, Mauro
Format: Journal Article
Language:English
Published: 15-02-2005
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Abstract Transmissible spongiform encephalopathies are a class of sporadic, genetic and transmissible neurodegenerative diseases that affect both humans and animals. Propagation of these diseases is thought to be due to the misfolding of a neuronal glyco‐protein, PrP c , into a pathological insoluble conformer, PrP Sc . In earlier works, some serum components were identified as exclusive PrP Sc ‐interacting proteins (Fisher et al., Nature 2000;408:479), and thus those macromolecules were thought to represent a potential diagnostic endogenous factor discriminating between normal and pathological prion proteins. In contrast, in agreement with a recent work (Kornblatt et al., Biochem Biophys Res Commun 2003;305:518), in this paper we present a detailed thermodynamic and kinetic characterization of the interaction between recombinant bovine PrP c 25–242 and the human serum component plasminogen, measured using a resonant mirror technique: our results reveal a high‐affinity interaction between the two binding partners. For comparison, the complex obtained from the purified full‐length PrP c and human plasminogen was also studied: both prion proteins (the recombinant bovine PrP c 25–242 and the purified full‐length PrP c ) are able to bind human plasminogen. Both kinetic and thermodynamic parameters are affected by the modulation exerted by the H + ions in solution. Moreover, the analysis of binding, according to canonical linkage relationships, suggests the involvement of a His residue, consistent with the interaction between other serine (pro)enzymes and their ligands. Proteins 2005. © 2004 Wiley‐Liss, Inc.
AbstractList Transmissible spongiform encephalopathies are a class of sporadic, genetic and transmissible neurodegenerative diseases that affect both humans and animals. Propagation of these diseases is thought to be due to the misfolding of a neuronal glyco‐protein, PrP c , into a pathological insoluble conformer, PrP Sc . In earlier works, some serum components were identified as exclusive PrP Sc ‐interacting proteins (Fisher et al., Nature 2000;408:479), and thus those macromolecules were thought to represent a potential diagnostic endogenous factor discriminating between normal and pathological prion proteins. In contrast, in agreement with a recent work (Kornblatt et al., Biochem Biophys Res Commun 2003;305:518), in this paper we present a detailed thermodynamic and kinetic characterization of the interaction between recombinant bovine PrP c 25–242 and the human serum component plasminogen, measured using a resonant mirror technique: our results reveal a high‐affinity interaction between the two binding partners. For comparison, the complex obtained from the purified full‐length PrP c and human plasminogen was also studied: both prion proteins (the recombinant bovine PrP c 25–242 and the purified full‐length PrP c ) are able to bind human plasminogen. Both kinetic and thermodynamic parameters are affected by the modulation exerted by the H + ions in solution. Moreover, the analysis of binding, according to canonical linkage relationships, suggests the involvement of a His residue, consistent with the interaction between other serine (pro)enzymes and their ligands. Proteins 2005. © 2004 Wiley‐Liss, Inc.
Author Eleuteri, Anna Maria
Biagetti, Massimo
Amici, Manila
Cuccioloni, Massimiliano
Barocci, Simone
Angeletti, Mauro
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Snippet Transmissible spongiform encephalopathies are a class of sporadic, genetic and transmissible neurodegenerative diseases that affect both humans and animals....
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Title Binding of recombinant PrP c to human plasminogen: Kinetic and thermodynamic study using a resonant mirror biosensor
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