This R21 grant explores the utilities of a novel chemical probe termed SF3, which belongs to a group of compounds termed selective antichlamydial benzal acylhydrazones (SACBAHs). Chlamydia trachomatis is the number one sexually transmitted bacterial pathogen, which accounts for 60% of the total infected cases reported to the Centers for Diseases and Prevention. Common complications from C. trachomatis infection include infertility, abortion, ectopic pregnancy and pelvic inflammatory syndrome. Unfortunately, an effective vaccine has yet to be developed despite numerous efforts by the scientific community over half of a century. Although several broad-spectrum antibiotics can be used to treat the infection, they negatively affect the beneficial microbiota, and may increases the risk of antibiotic resistance in unrelated pathogens. In addition, clinical treatment failure with current therapies is common. There is a clear need to develop selective inhibitors and investigate their mechanisms for treatment and prevention of chlamydial infection. Our research group has identified SACBAHs as novel antichlamydials. SACBAHs exhibit several important characteristics. First, they are effective against chlamydial growth. Second; they do not affect host cell growth at concentrations that show complete inhibition of chlamydial growth. Third, they do not affect the growth of beneficial lactobacilli, which dominate the vaginal microbiota in most reproductive-age women. Our preliminary studies suggest that SACBAHs inhibit chlamydiae by interfering with the function of the Chlamydia-specific transcription factor GrgA. We will determine how SF3 affects chlamydial transcription at both the cellular and molecular levels.
Sexually transmitted chlamydial infection is the most common sexually transmitted bacterial infection that often leads to serious and long-lasting complications in women. Currently, there is no effective means for preventing chlamydial infection. The chemical probe to be developed in this project will enhance the understanding of the chlamydial biology, and facilitate the development of new therapeuticals and preventatives.