Virtual screening identifies novel in - hibitor scaffolds of human carbonic anhydrase

Human carbonic anhydrase VII f is directly involved in an array of biological processes, including acid-base regulation, bone restoration, respiration, calcification, and the formation such compounds as saliva. Prior work has suggested the neural activity of CA7 in the mammalian brain, particular its high-frequency stimulation of GABAergic excitation, is directly correlated to seizures in epilepsy. This research was focused on the discovery of novel inhibitors to decrease the global impact of epilepsy. Ligation independent cloning, expression in E. coli cells, and affinity chromatography techniques were used to obtain carbonic anhydrase 7 protein for in vitro testing and analysis. Protein function was verified in enzyme assays varying enzyme and substrate, and assays varying 100% DMSO concentration were utilized to determine optimal conditions for inhibitory tests. Virtual drug screening with the GOLD docking genetic algorithm was used to collect top-scoring compounds from eight libraries (122,670 compounds). The top-scoring compound from an aggregate run, in addition to a top-scoring compound for another researcher, was tested using inhibitory assays. These compounds, ChemBridge 5107893 and 5115900, both displayed inhibition with projected IC50 values in the high micromolar (fractional millimolar) range. These data support the use of virtual screening for the discovery of novel inhibitors and have important implications for the arrangement of scaffolds and skeletal orientations of potential synthetic inhibitors of carbonic anhydrase VII and, ultimately, the global impact of seizures and epilepsy.