**2.3 Homology modeling**

The structural model of KARI was obtained from NCBI database http://www.blast. ncbi.nlm.nih.gov. Ketol acid reductor-isomerase (KARI) enzyme of *N. gonorrhoeae* was subjected for homology modeling using the Swiss model. The structural homolog, which was used as a template for this model, is ketol acid reducto-isomerase enzyme from *S. aureus (Sa* KARI*)* with PDB identifier 5w3k. The sequence similarity between the template and the model is about 33%. The KARI model and the template (5w3k) were superimposed using the PYMOL software (version 2.4.1) [23].
