cb7b00560_si_001.pdf (17.35 MB)
Small Molecule Chelators Reveal That Iron Starvation Inhibits Late Stages of Bacterial Cytokinesis
journal contribution
posted on 2017-12-11, 00:00 authored by Thiago
M. A. Santos, Matthew G. Lammers, Maoquan Zhou, Ian L. Sparks, Madhusudan Rajendran, Dong Fang, Crystal L. Y. De Jesus, Gabriel F. R. Carneiro, Qiang Cui, Douglas B. WeibelBacterial cell division
requires identification of the division
site, assembly of the division machinery, and constriction of the
cell envelope. These processes are regulated in response to several
cellular and environmental signals. Here, we use small molecule iron
chelators to characterize the surprising connections between bacterial
iron homeostasis and cell division. We demonstrate that iron starvation
downregulates the transcription of genes encoding proteins involved
in cell division, reduces protein biosynthesis, and prevents correct
positioning of the division machinery at the division site. These
combined events arrest the constriction of the cell during late stages
of cytokinesis in a manner distinct from known mechanisms of inhibiting
cell division. Overexpression of genes encoding cell division proteins
or iron transporters partially suppresses the biological activity
of iron chelators and restores growth and division. We propose a model
demonstrating the effect of iron availability on the regulatory mechanisms
coordinating division in response to the nutritional state of the
cell.