Immunological characterization of the sheep prion protein expressed as fusion proteins in Escherichia coli

The prion protein (PrP) from sheep was produced in large quantities of enti re protein in Escherichia coli after fusion with a carboxy-terminal hexahis tidine sequence. In contrast, amino-terminal fusion with glutathione S-tran sferase (GST) revealed a high susceptibility toward cleavage of the protein . Both recombinant proteins were recognised, at variable levels, in Western blots using a panel of antibodies against the 40-56, 89-104, 95-113 and 11 2-115 sequences of the prion protein, similarly to the abnormal prion prote in extracted from scrapie-infected sheep. Interestingly, monoclonal antibod y 3F4 was found to react with these three proteins in Western blot. (C) 199 9 Federation of European Microbiological Societies. Published by Elsevier S cience B.V. All rights reserved.