Figure 4. The similarity of the predicted antibacterial drugs and FDA-approved antibacterial drugs. (A) The molecular fingerprint similarity of 957 predicted novel antibacterial drugs and 206 FDA-approved antibacterial drugs. The average similarities between most of the predicted drugs and approved drugs were less than 0.2. (B) Substructure similarity between novel predicted antibacterial drugs and core scaffolds of approved antibacterial drugs. Compounds with an overlap coefficient higher than 0.9 are considered to have high substructure similarity.