Raman spectroscopic study on the conformation of a peptide fragment representing the DNA‐binding domain of filamentous virus Pf3 coat protein

Abstract
Raman spectra have been measured of a nonapeptide which has an amino acid sequence identical to that of the C‐terminal region of the major coat protein subunit of Filamentous bacteriophage Pf3. The peptide shows a strong tendency to form a β‐sheet structure in aqueous solution. The β‐sheet formation is significantly promoted by complexation with single‐stranded DNA but not with double‐stranded DNA. It is suggested that the C‐terminal region of the Pf3 coat protein binds to the single‐stranded DNA genome in the virion with a β‐sheet conformation, in sharp contrast with the α‐helical binding in other filamentous bacteriophages.