Inhibition of bacterial and human zinc-metalloproteases

Abstract

Antibiotic resistance is one of the major challenges in the present era and it is drastically increasing with the increase in time because of the overuse and misuse of antibiotics. Therefore, there is a demand of new antibiotics with new modes of action or other innovative strategies to overcome bacterial infections as soon as possible. The zinc metalloproteases Themolysin (TLN), Pseudolysin (PLN) and Aureolysin (ALN) are important bacterial virulence factors and the inhibition of these bacterial virulence factors is believed to be a new treatment option of bacterial infections. However, in order to have a therapeutic value, inhibitors of these enzymes should not interfere strongly with the activity of human zinc metalloproteases. In the present thesis, 26 compounds were tested for the inhibition of TLN, PLN, ALN and the human matrix metalloproteases-14(MMP-14). The compounds were selected from a previous virtual screening project at the research group. The inhibition of the compounds was tested by measuring the enzyme activity of PLN, TLN ALN and MMP-14 after exposure of the test compounds. The time resolved fluorescence by the use of fluorogenic substrates was used to measure the enzyme activity. The results showed that some of the compounds inhibited the enzyme activity by 30%-40% and they were not considered as slow binders as there was no significant change in activity with respect to the time. Compounds with highest rate of inhibition in enzyme assays were selected and proceed for molecular modeling studies by docking and MMGBSA calculations. The best compounds were compared with a known strong inhibitor of the zinc- metalloproteases in the molecular modeling part.