Here we report the structural and functional characterization of a covalent complex (MKP) obtained by cross-linking microperoxidase (Mp), the haem-undecapeptide obtained by the peptic digestion of cytochrome c, with a 21-residue synthetic peptide(P21) analogous to the S-peptide of the RNase A. The covalent complex has been prepared by introducing a disulphide bond between Cys-1 of P21 and Lys-13 of Mp, previously modified with a thiol-containing reagent. On formation of the complex (which is a monomer), the helical content of P21 increases significantly. The results obtained indicate that His-13 of P21 coordinates to the sixth co-ordination position of the haem iron, thus leading to the formation of a complex characterized by an equilibrium between an 'open' and a 'closed' structure, as confirmed by molecular dynamics simulations. Under acidic pH conditions, where His-13 of P21 is loosely bound to the haem iron ('open'conformation), MKP displays appreciable, quasireversible electrochemical activity; in contrast, at neutral pH ('closed' conformation) electrochemical behaviour is negligible, indicating that P21 interferes with the electron-transfer properties typical of Mp. On the whole, MKPis a suitable starting material for building a miniature haem system, with interesting potential for application to biosensor technology.
Ippoliti R., P.A. (1997). Covalent complex of microperoxidase with a 21-residue synthetic peptide as a maquette for low-molecular-mass redox proteins. BIOCHEMICAL JOURNAL, 328(3), 833-840.
|Tipologia:||Articolo su rivista|
|Citazione:||Ippoliti R., P.A. (1997). Covalent complex of microperoxidase with a 21-residue synthetic peptide as a maquette for low-molecular-mass redox proteins. BIOCHEMICAL JOURNAL, 328(3), 833-840.|
|IF:||Con Impact Factor ISI|
|Settore Scientifico Disciplinare:||Settore BIO/10|
|Revisione (peer review):||Sì, ma tipo non specificato|
|Stato di pubblicazione:||Pubblicato|
|Data di pubblicazione:||1997|
|Titolo:||Covalent complex of microperoxidase with a 21-residue synthetic peptide as a maquette for low-molecular-mass redox proteins|
|Autori:||Ippoliti R., Picciau A., Santucci R., Antonini G., Brunori M., Ranghino G.|
|Appare nelle tipologie:||01 - Articolo su rivista|