Identification of Bacillus anthracis PurE inhibitors with antimicrobial activity. Issue 7 (1st April 2015)

• Record Type: Journal Article
• Authors: Kim, Anna; Wolf, Nina M.; Zhu, Tian; Johnson, Michael E.; Deng, Jiangping; Cook, James L.; Fung, Leslie W.-M.
• Is Part Of: Bioorganic & medicinal chemistry. Volume 23:Issue 7(2015)
• Page Start: 1492
• Page End: 1499
• Publication Date: 2015-04-01
• Subjects: A260 UV absorbance at 260 nm -- AIR 5-amino-imidazole ribonucleotide -- Ba Bacillus anthracis (ΔANR strain) -- CAIR 4-carboxy-amino-imidazole ribonucleotide -- CD circular dichroism -- DMSO dimethyl sulfoxide -- E. coli ΔTolC E. coli efflux pump knockout strain -- GST glutathione-S-transferase -- hPur6 human enzyme containing a PurE domain, also known as AIR carboxylase -- HTS high-throughput screening -- LC1–6 compound names -- MBC minimum bactericidal concentration -- MIC minimum inhibitory concentration -- MRSA methicillin-resistant Staphylococcus aureus -- MSSA methicillin-susceptible Staphylococcus aureus -- N5-CAIR N5-carboxy-amino-imidazole ribonucleotide -- NAIR 4-nitro-5-amino-imidazole ribonucleotide -- PBS 5 mM phosphate buffer with 150 mM NaCl at pH 7.4 -- RRC Research Resource Center -- PurE N5-carboxy-amino-imidazole ribonucleotide mutase -- Tm Boltzmann transition temperature in thermal unfolding -- TmE the average Tm value of BaPurE -- TmEc the average Tm value of replicate runs of BaPurE with a particular compound added -- ΔTm TmEc − TmE -- Tris-25 25 mM Tris buffer at pH 8 -- Tris-50 50 mM Tris buffer at pH 8 -- UIC University of Illinois at Chicago; High-throughput screening -- De novo purine biosynthesis -- PurE -- Thermal shift assay -- Sypro Orange -- 2-Carboxamido-1, 3, 4-oxadiazole; Bioorganic chemistry -- Periodicals; Pharmaceutical chemistry -- Periodicals; Biochemistry -- Periodicals; Chemistry, Clinical -- Periodicals; Chemistry, Organic -- Periodicals; Chimie bio-organique -- Périodiques; Chimie pharmaceutique -- Périodiques; 615.19
• DOI: 10.1016/j.bmc.2015.02.016
• Languages: English
• ISSNs: 0968-0896

Abstract

Graphical abstract: Abstract: N 5 -carboxy-amino-imidazole ribonucleotide (N 5 -CAIR) mutase (PurE), a bacterial enzyme in the de novo purine biosynthetic pathway, has been suggested to be a target for antimicrobial agent development. We have optimized a thermal shift method for high-throughput screening of compounds binding to Bacillus anthracis PurE. We used a low ionic strength buffer condition to accentuate the thermal shift stabilization induced by compound binding to Bacillus anthracis PurE. The compounds identified were then subjected to computational docking to the active site to further select compounds likely to be inhibitors. A UV-based enzymatic activity assay was then used to select inhibitory compounds. Minimum inhibitory concentration (MIC) values were subsequently obtained for the inhibitory compounds against Bacillus anthracis (ΔANR strain), Escherichia coli (BW25113 strain, wild-type and Δ Tol C), Francisella tularensis, Staphylococcus aureus (both methicillin susceptible and methicillin-resistant strains) and Yersinia pestis . Several compounds exhibited excellent (0.05–0.15 μg/mL) MIC values against Bacillus anthracis . A common core structure was identified for the compounds exhibiting low MIC values. The difference in concentrations for inhibition and MIC suggest that another enzyme(s) is also targeted by the compounds that we identified.