>1b4sB (B:) observed residues (from ATOM records)
vnkertflavkpdgvarglvgeiiaryekkgfvlvglkqlvptkdlaeshyaehkerpff
gglvsfitsgpvvamvfegkgvvasarlmigvtnplasapgsirgdfgvdvgrniiggsd
svesanreialwfkpeelltevkpnpnlye