{'fraction_non_alphanumeric': 0.013966480446927373, 'fraction_numerical': 0.0, 'mean_word_length': 5.932258064516129, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Kinetic evaluation of the reaction of glutamate racemase with computationally derived inhibitors provides validation of a successful pharmacophore model for a new line of antibiotic therapy

As increasing antibiotic resistance diminishes the effectiveness of once‐valuable drug therapies; research efforts must seek novel targets for new antibiotics compounds. Glutamate racemase, the enzyme responsible for the cofactor‐independent racemization of glutamic acid in bacteria, remains an untargeted step in the peptidoglycan synthesis pathway. Glutamate racemase has been shown to be essential for the viability of several pathogens including Helicobacter pylori, Escherichia coli, and Streptococcus pneumoniae, making it an ideal target for developing a new class of antibiotics. Crystal structure data for S. pneumoniae glutamate racemase is not available, thus comparative modeling was employed to develop a three‐dimensional structure for this enzyme using Prime® software. Several potential glutamate racemase inhibitors were docked into the model's active site to investigate binding modes and develop derivations to enhance for strong binding to the enzyme active site. Synthesis of the MurI gene, the gene encoding glutamate racemase, and placement into the pBluescript plasmid has allowed successful expression of functional glutamate racemase. However cellular components from the lysis of E.coli cells transformed with an inducible plasmid containing MurI have made reliable enzyme assays difficult. Addition of a His tag linker to the MurI containing plasmid allowed for purification prior to kinetic assays, thereby eliminating potential cellular contaminants that interfere with our coupled enzyme assay. Our results validated the development of a structure‐based pharmacophore model for glutamate racemase inhibitors. Previous kinetic assays have demonstrated successful inhibition with our potential drugs, but reliable determination of Ki was not possible due to interference with our coupled assay. Use of the purified enzyme for kinetic assays has removed this interference and provide more reliable and accurate Ki determination.