Discipline: Chemistry and Chemical Sciences
Subcategory: Biochemistry (not Cell and Molecular Biology and Genetics)
Crystal Yu - University of Puerto Rico at Arecibo
During bacterial cell division of gram-negative bacteria, more than a dozen different proteins assemble near midcell and drives invagination of the inner membrane, synthesis and remodeling of the peptidoglycan cell wall, and invagination of the outer membrane. Divin is a small molecule that chelates iron and blocks late steps of cell division. The bacteriostatic mechanism of action of divin is distinct from other reported inhibitors of bacterial cell division and provides an opportunity for assessing the therapeutic value of a new class of antimicrobial agents. We characterized the mechanism of action of divin and other small molecules that chelates iron and, tracked the localization of cell division proteins in Caulobacter crescentus using fluorescence microscopy. Bacteria cells were treated with divin and 2,2’-bipyridine (bipy). Dimethyl sulfoxide (DMSO) was used as a solvent control and cells were imaged using a Nikon Ti Eclipse inverted microscope during a time-course of eight hours. C. crescentus strain EG120 (FtsI-Venus), EG645 (ZapA-mCherry), or EG658 (FtsK-mCherry::FtsI-mCherry) were imaged at different days and the results are the combination of two biological replicates. The cell division protein ZapA displays a mid-cell localization in cells treated with DMSO, divin, or bipy, suggesting that the compounds do not affect the localization of ZapA. The cell division protein FtsI was found correctly positioned at mid-cell in DMSO-treated cells but was mislocalized in cells treated with divin or bipy. It is important to study the spatiotemporal localization of other proteins involved in bacterial cell division and to characterize the connections between iron starvation and the dynamics of the division machinery in bacteria.
Funder Acknowledgement(s): National Science Foundation through the University of Wisconsin-Madison Material Research Science and Engineering Center (MRSEC); The University of Wisconsin-Madison Graduate School; Nanoscale Science and Engineering Center.
Faculty Advisor: Thiago Santos, firstname.lastname@example.org
Role: I worked with Minimum Inhibitor Concentration technique to measure what amount of treatment (DMSO, divin and bipy) I should add to the bacteria (C. crescentus). After treat them, the bacteria was imaged by fluorescence microscopy during eight hours to study their behavior. I also worked with data analysis using the Oufti Software.