Fatty acids are important component of cell membrane,whereas the distinct difference between mammalian and bacterial fatty acid synthase system making the later becomes target for searching new antibiotics.β-ketoacyl-ACP reductase (FabG) is an important enzyme of bacterial fatty acid synthase system,due to its highly conserved,widely expressed,and only a single isoform,receiving more and more attention for searching its inhibitors which would be developed into new antibiotics.