The Maurelli lab attended the Chlamydia Basic Research Society (CBRS) meeting in the beautiful city of Seattle, Washington, March 18-21. This biennial conference began in 2003 and is the premier venue for Chlamydia scientists from across the globe to exchange their latest results. Presentations in the form of short talks and posters covered the very broad range of cutting-edge research on Chlamydiae. Three postdoctoral fellows from the laboratory of Tony Maurelli, Ph.D. (EGH) presented their own data at the conference this year.
Jessica Slade, Ph.D. presented a 10-minute talk entitled “Fosmidomycin inhibition of isoprenoid synthesis induces persistence in Chlamydia trachomatis.” Chlamydia can “ride-out” periods of unfavorable growth conditions by entering an alternative growth state known as “persistence”. In this state, Chlamydia remains viable but cell division ceases until conditions improve. The antibiotic fosmidomycin is lethal to other bacteria, but exposure causes C. trachomatis to enter persistence instead, highlighting that isoprenoid synthesis is essential for chlamydial cell division. For 20 years, iron deprivation has been a known persistence inducer but the underlying mechanism was unknown. Because fosmidomycin inhibits isoprenoid synthesis and isoprenoid synthesis depends on iron-requiring enzymes, this study proposes that inhibition of isoprenoid synthesis is the underlying mechanism for iron deprivation-induced persistence.
C. trachomatis has a limited capacity for synthesis of amino acids and is dependent on its host mammalian cell for these nutrients. However, how Chlamydia acquires essential amino acids from the host is not known. Raghuveer Singh, Ph.D. presented a poster entitled “The Putative Oligopeptide Transporter of Chlamydia trachomatis Siphons Oligopeptides from the Host While Recycling Peptidoglycan Fragments to Assist Peptidoglycan Synthesis” that was focused on the identification of a major player, the oligopeptide transporter, which facilitates the transport of oligopeptides from the host for nutrition. Additionally, his work highlighted the secondary role of this transporter in recycling immunostimulatory peptidoglycan (cell wall) fragments. Efficient peptidoglycan recycling protects the bacterium from detection by the immune system, enabling it to grow intracellularly.
Dev Ranjit, Ph.D. presented a poster entitled “Chlamydial MreB directs cell division and peptidoglycan synthesis in Escherichia coli in the absence of MreB and FtsZ”. His research highlighted the ability of Chlamydial MreB to function as a cell division protein and support cell division without FtsZ which is typically essential in bacterial cell division. His presentation resolved the mystery of why Chlamydia lack cell division protein FtsZ and was well received among chlamydial biologists by attracting a lot of interest and curiosity.