Description
Authors: Dr. Hensel, Dr. Ghebreyesus, Benny Oduro, Kennedy Hampton, Jelani Jackson, Zarah Osman
Abstract
Bacterial biofilms, extracellular matrices formed by bacterial communities, contribute to significant medical and environmental challenges, including infections associated with medical devices, dental caries, and industrial infrastructure. Biofilms enable bacteria to evade the host immune system, secrete virulence factors, and exhibit resistance to antimicrobial treatments. To explore photo-pharmacological approach for the discovery of new antibiofilm agents, two types of novel tryptophan and phenylalanine amino acids functionalized photoswitchable arylazopyrazole (AAP-Trp; AAP-Phe) based lead compounds were synthesized and their photochromic properties and potential as biofilm inhibitors were studied. These compounds change conformations with light exposure, so specific inhibition activity should be specific for either drug with no light treatment or the drug conformation with light treatment.
We tested the ability of the compounds, AAP-Trp and AAP-Phe, with no light treatment to inhibit biofilm formation in several species of bacteria known for biofilm virulence or hazards: Escherichia coli, Pseudomonas aeruginosa, Streptococcus mutans, Bacillus subtilis, and Staphylococcus aureus. Biofilm production was measured with the standard Crystal Violet assays in triplicate. AAP-Phe consistently inhibited biofilm formation only in Bacillus subtilis and not in the other species tested. Maximum inhibition in B. subtilis occurred between 0.1 mM and 0.2 mM of AAP-Phe. Future experiments include testing the light-induced conformation of these novel lead compounds, testing additional novel lead compounds, measuring biofilm inhibition by the patented HEFY assay, and determining if inhibition is from biofilm quorum sensing inhibition or efflux pump inhibition.