Antibacterial Effect of Some Eukaryotic Sterol Biosynthesis Inhibitors.

Background: Isoprenoids and their derivatives are building blocks for the synthesis of biomolecules with important biological functions such as cholesterol in eukaryotes and lipid carrier undecaprenol, which is involved in cell wall biosynthesis in bacteria. With the global threat of multidrug-resistant bacteria, there is a need for finding new metabolic targets for killing bacteria. In the present study, we examined the impact of eukaryotic sterol biosynthesis inhibitors on the growth of four pathogenic bacteria.

Materials And Methods: Antibacterial effect of HMG CoA reductase inhibitor (simvastatin), farnesyl pyrophosphate synthase inhibitor (alendronate), squalene epoxidase inhibitor (terbinafine), and lanosterol demethylase inhibitor (ketoconazole) were studied against four pathogenic bacteria: two gram-positive bacteria, and and two gram-negative bacteria, and . Broth microdilution method was used for assessing the antibacterial susceptibility of the components using 96 well plats. MIC and MBC were determined visibly.

Results: MIC of Ketoconazole for and were 0.166 and 1 mg/mL, respectively. Terbinafine had a weak inhibitory effect on (MIC: 8 mg/mL). Ketoconazole and terbinafine had no inhibitory effect on gram-negative bacteria. MBC of Simvastatin for both and was 0.5 mg/mL and of Alendronate for was 6.6 mg/mL.

Conclusion: Our results show that farnesyl pyrophosphate synthase and class II HMG-CoA reductases inhibitors (ketoconazole and simvastatin) have reasonable antibacterial activity against gram-positive bacteria. These two enzymes provide suitable targets for designing new antibiotics based on modifying the chemical structure of currently used drugs to obtain maximum activity.