Assignment of the 1H NMR spectrum and secondary structure elucidation of the single-stranded DNA binding protein encoded by the filamentous bacteriophage IKe.

By means of 2D NMR techniques, all backbone resonances in the 1H NMR spectrum of the single-stranded DNA binding protein encoded by gene V of the filamentous phage IKe have been assigned sequence specifically (at pH 4.6, T = 298 K). In addition, a major part of the side chain resonances could be assigned as well. Analysis of NOESY data permitted the elucidation of the secondary structure of IKe gene V protein. The major part of this secondary structure is present as an antiparallel beta-sheet, i.e., as two beta-loops which partly combine into a triple-stranded beta-sheet structure, one beta-loop and one triple-stranded beta-sheet structure. It is shown that a high degree of homology exists with the secondary structure of the single-stranded DNA binding protein encoded by gene V of the distantly related filamentous phage M13.