Figure 7

A proposed structural model for Ta SSIVb based on the Agt GS structure (Protein Databank code: 1rzu). A putative homology model of the overall protein-fold and secondary structure of TaSSIVb was constructed using T.I.TO: Tool for Incremental Threading Optimization [73, 74]. The N- and C-termini are indicated, the two different Rossmann-like α-β-α domains are apparent, as is the large cleft that separates them and makes up the active site. Residues identified as crucial to SS activity are highlighted (green balls) and are outlined in Table 2 and 5. Also highlighted are the residues of the 380s Loop (in red) and the G-X-G motif (in yellow).