On the hypothetical protein F154 of the TTV1 virus from Thermoproteus tenax. Part III: Immunological identification of the protein with anti-peptide antibodies.

To assess the expression of an hypothetical protein F154 encoded in an open reading frame of the DNA sequence of the virus TTV1 identified in the archaebacterium Thermoproteus tenax, two synthetic peptides related to characteristic repeats of the primary structure and corresponding to the sequence portions [Ser81] (73-84) and (79-101) were selectively grafted at their N-termini to the surface-exposed single cysteine residue of iso-1-cytochrome c via the maleimide thiol principle. Antisera were raised in rabbits against the two conjugates and the antipeptide-(79-101) immunoselected antibodies were found to crossreact with a strong protein band in Western blots of cell lysates of TTV1-infected bacteria, thus confirming expression of the protein F154 in Thermoproteus tenax.