Doerksen, R. J. | bioRxiv Science

bioRxiv2022

Discovery, Synthesis, and Optimization of 1,2,4-Triazolyl Pyridines Targeting Mycobacterium tuberculosis

Tuberculosis (TB) results in 1.5 million deaths every year. The rise in multi-drug resistant TB underscores the urgent need to develop new antibacterials, particularly those with new chemical entities and/or novel mechanisms of action that can be used in combination therapy with existing drugs to prevent the rapid emergence of resistance. Herein, we report the discovery and synthesis of a new series of compounds containing a 3-thio-1,2,4-triazole moiety that show inhibition of Mycobacterium tuberculosis (Mtb) growth and survival. Structure-activity relationship studies led us to identify potent analogs displaying nanomolar inhibitor activity, specifically against Mtb. These potent analogs exhibit a promising ADME/pharmacokinetic profile and no cytotoxicity in mammalian cells at over 100 times the effective dose in Mtb. Our preliminary investigations into the mechanism of action suggest this series is not engaging promiscuous targets and, thereby, could be acting on a novel target. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=79 SRC="FIGDIR/small/516356v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@1fd7a78org.highwire.dtl.DTLVardef@738c7dorg.highwire.dtl.DTLVardef@c7957org.highwire.dtl.DTLVardef@f26ae3_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

bioRxiv2021

Validated Determination of NRG1 Ig-like Domain Structure by Mass Spectrometry Coupled with Computational Modeling

High resolution hydroxyl radical protein footprinting (HR-HRPF) is a mass spectrometry-based method that measures the solvent exposure of multiple amino acids in a single experiment, offering constraints for experimentally-informed computational modeling. HR-HRPF-based modeling has previously been used to accurately model the structure of proteins of known structure, but the technique has never been used to determine the structure of a protein of unknown structure leaving questions of unintentional bias and applicability to unknown structures unresolved. Here, we present the use of HR-HRPF-based modeling to determine the structure of the Ig-like domain of NRG1, a protein with no close homolog of known structure. Independent determination of the protein structure by both HR-HRPF-based modeling and heteronuclear NMR was carried out, with results compared only after both processes were complete. The HR-HRPF-based model was highly similar to the lowest energy NMR model, with a backbone RMSD of 1.6 [A]. To our knowledge, this is the first use of HR-HRPF-based modeling to determine a previously uncharacterized protein structure.

biophysics↗