A homology analysis of nine full-length protein sequences indicated that nucleotide identity among them ranged from 63.66% (between NNU_016707 and NNU_022788) to 92.78% (between NNU_024672 and NNU_020115; Figure 2; Figure S1). Reflecting what was found in the protein sequences, a high similarity (ranging from 65.14 to 90.26%) was shared among nine NnTPSs full-length sequences. Several residues in the catalytic center were highly conserved in all NnTPS genes (Figure S1) suggested that corresponding genes encoding active enzymes. Nevertheless, relatively high divergence was observed in some regions of amino acid sequences outside of the domain. It is likely that these un-conserved regions might contribute to functional distinction.