Fig. 1

Chimeric nanobodies prepared in the present study. a Construction of chimeric nanobodies. Peptide tags were fused to the C-terminus of nanobodies. b Simple illustration of a nanobody used for swapping. c Name and construction of chimeric nanobodies. Long white block: nanobody scaffolds with amino acid sequences derived from GFP-nanobody, long black block: nanobody scaffolds with amino acid sequences derived from CD4-nanobody, small white block: CDRs with amino acid sequences derived from GFP-nanobody, small black block: CDRs with amino acid sequences derived from CD4-nanobody, cCD4 CDRX: chimeric nanobody with CDRX of GFP-nanobody replaced with that of CD4-nanobody, CD4N: CD4 -nanobody with peptide tags containing two FLAG-tag sequences (see also Additional file 1: Table S3), GFPN: GFP-nanobody with peptide tags containing two FLAG-tag sequences (see also Additional file 1: Table S3). d Amino acid sequence alignment of GFP- and CD4-nanobodies prepared by CLUSTALW (Larkin et al. 2007). Asterisks indicate identical amino acids. Colons indicate similar amino acids. Dots indicate almost similar amino acids. Blanks indicate non-homologous amino acids