Multiple sequence alignment of FND and DnaD-like domains. Sequences were aligned using ClustalW2 and shaded with BoxShade. The starting residues are reported at the front of the corresponding sequence. Amino acids identical or similar in 70% of the sequences are shaded by black or grey background, respectively. Organisms, accession numbers and characteristics of DnaD-like and FND sequences shown in the alignment are given in the additional files 1 and 4. 2D-structure of Streptococcus mutans DnaD-like domain (PDB: 2ZC2) is shown at the bottom of the alignment. Helices and loops are represented in red and green respectively. Hydrophobic positions conserved in DnaD (Denoted by red dotes in the additional file 2) are shaded by pink background and their equivalent in FND (Figure 1) shaded by light gren background. Stars indicate the two conserved hydrophobic positions that are not buried in the Streptococcus mutans DnaD-like domain.