1. Bacterial Actin and Tubulin Homologs in Cell Growth and Division

    Current Biology 25(6):R243 (2015)

    In contrast to the elaborate cytoskeletal machines harbored by eukaryotic cells, such as mitotic spindles, cytoskeletal structures detectable by typical negative stain electron microscopy are generally absent from bacterial cells. As a result, for decades it was thought that bacteria l...
  2. Visualization of the type III secretion sorting platform of Shigella flexneri.

    PNAS 112(4):1047 (2015) PMID 25583506

    Bacterial type III secretion machines are widely used to inject virulence proteins into eukaryotic host cells. These secretion machines are evolutionarily related to bacterial flagella and consist of a large cytoplasmic complex, a transmembrane basal body, and an extracellular needle. The cytopl...
  3. Visualization of the type III secretion sorting platform of Shigella flexneri.

    PNAS 112(4):1047 (2015) PMID 25583506 PMCID PMC4313800

    Bacterial type III secretion machines are widely used to inject virulence proteins into eukaryotic host cells. These secretion machines are evolutionarily related to bacterial flagella and consist of a large cytoplasmic complex, a transmembrane basal body, and an extracellular needle. The cytopl...
  4. Visualization of the type III secretion sorting platform of Shigella flexneri.

    PNAS 112(4):1047 (2015) PMID 25583506 PMCID PMC4313800

    Bacterial type III secretion machines are widely used to inject virulence proteins into eukaryotic host cells. These secretion machines are evolutionarily related to bacterial flagella and consist of a large cytoplasmic complex, a transmembrane basal body, and an extracellular needle. The cytopl...
  5. Bacterial growth and form under mechanical compression.

    Scientific reports 5:11367 (2015) PMID 26086542 PMCID PMC4471898

    A combination of physical and chemical processes is involved in determining the bacterial cell shape. In standard medium, Escherichia coli cells are rod-shaped, and maintain a constant diameter during exponential growth. Here, we demonstrate that by applying compressive forces to growing E. coli...
  6. The Min system and other nucleoid-independent regulators of Z ring positioning.

    Frontiers in Microbiology 6:478 (2015) PMID 26029202 PMCID PMC4429545

    Rod-shaped bacteria such as E. coli have mechanisms to position their cell division plane at the precise center of the cell, to ensure that the daughter cells are equal in size. The two main mechanisms are the Min system and nucleoid occlusion (NO), both of which work by inhibiting assembly of F...
  7. A thermosensitive defect in the ATP binding pocket of FtsA can be suppressed by allosteric changes in the dimer interface.

    Molecular Microbiology 94(3):713 (2014) PMID 25213228 PMCID PMC4213309

    In Escherichia coli, initial assembly of the Z ring for cell division requires FtsZ plus the essential Z ring-associated proteins FtsA and ZipA. Thermosensitive mutations in ftsA, such as ftsA27, map in or near its ATP binding pocket and result in cell division arrest at non-permissive temperatu...
  8. A thermosensitive defect in the ATP binding pocket of FtsA can be suppressed by allosteric changes in the dimer interface.

    Molecular Microbiology 94(3):713 (2014) PMID 25213228 PMCID PMC4213309

    In Escherichia coli, initial assembly of the Z ring for cell division requires FtsZ plus the essential Z ring-associated proteins FtsA and ZipA. Thermosensitive mutations in ftsA, such as ftsA27, map in or near its ATP binding pocket and result in cell division arrest at non-permissive temperatu...
  9. A thermosensitive defect in the ATP binding pocket of FtsA can be suppressed by allosteric changes in the dimer interface.

    Molecular Microbiology 94(3):713 (2014) PMID 25213228 PMCID PMC4213309

    In Escherichia coli, initial assembly of the Z ring for cell division requires FtsZ plus the essential Z ring-associated proteins FtsA and ZipA. Thermosensitive mutations in ftsA, such as ftsA27, map in or near its ATP binding pocket and result in cell division arrest at non-permissive temperatu...
  10. 3D-SIM super-resolution of FtsZ and its membrane tethers in Escherichia coli cells.

    Biophysical Journal 107(8):L17 (2014) PMID 25418183 PMCID PMC4213660

    FtsZ, a bacterial homolog of eukaryotic tubulin, assembles into the Z ring required for cytokinesis. In Escherichia coli, FtsZ interacts directly with FtsA and ZipA, which tether the Z ring to the membrane. We used three-dimensional structured illumination microscopy to compare the localization ...
  11. 3D-SIM super-resolution of FtsZ and its membrane tethers in Escherichia coli cells.

    Biophysical Journal 107(8):L17 (2014) PMID 25418183 PMCID PMC4213660

    FtsZ, a bacterial homolog of eukaryotic tubulin, assembles into the Z ring required for cytokinesis. In Escherichia coli, FtsZ interacts directly with FtsA and ZipA, which tether the Z ring to the membrane. We used three-dimensional structured illumination microscopy to compare the localization ...
  12. 3D-SIM Super-resolution of FtsZ and Its Membrane Tethers in Escherichia coli Cells.

    Biophysical Journal 107(8):L17 (2014) PMID 25418183 PMCID PMC4213660

    FtsZ, a bacterial homolog of eukaryotic tubulin, assembles into the Z ring required for cytokinesis. In Escherichia coli, FtsZ interacts directly with FtsA and ZipA, which tether the Z ring to the membrane. We used three-dimensional structured illumination microscopy to compare the localization ...
  13. A role for FtsA in SPOR-independent localization of the essential Escherichia coli cell division protein FtsN.

    Molecular Microbiology 92(6):1212 (2014) PMID 24750258 PMCID PMC4079119

    FtsN is a bitopic membrane protein and the last essential component to localize to the Escherichia coli cell division machinery, or divisome. The periplasmic SPOR domain of FtsN was previously shown to localize to the divisome in a self-enhancing manner, relying on the essential activity of FtsN...
  14. The highly conserved MraZ protein is a transcriptional regulator in Escherichia coli.

    Journal of Bacteriology 196(11):2053 (2014) PMID 24659771 PMCID PMC4010979

    The mraZ and mraW genes are highly conserved in bacteria, both in sequence and in their position at the head of the division and cell wall (dcw) gene cluster. Located directly upstream of the mraZ gene, the Pmra promoter drives the transcription of mraZ and mraW, as well as many essential cell d...
  15. A role for FtsA in SPOR-independent localization of the essential Escherichia coli cell division protein FtsN.

    Molecular Microbiology 92(6):1212 (2014) PMID 24750258 PMCID PMC4079119

    FtsN is a bitopic membrane protein and the last essential component to localize to the Escherichia coli cell division machinery, or divisome. The periplasmic SPOR domain of FtsN was previously shown to localize to the divisome in a self-enhancing manner, relying on the essential activity of FtsN...
  16. The highly conserved MraZ protein is a transcriptional regulator in Escherichia coli.

    Journal of Bacteriology 196(11):2053 (2014) PMID 24659771 PMCID PMC4010979

    The mraZ and mraW genes are highly conserved in bacteria, both in sequence and in their position at the head of the division and cell wall (dcw) gene cluster. Located directly upstream of the mraZ gene, the Pmra promoter drives the transcription of mraZ and mraW, as well as many essential cell d...
  17. Asymmetric constriction of dividing Escherichia coli cells induced by expression of a fusion between two min proteins.

    Journal of Bacteriology 196(11):2089 (2014) PMID 24682325 PMCID PMC4010982

    The Min system, consisting of MinC, MinD, and MinE, plays an important role in localizing the Escherichia coli cell division machinery to midcell by preventing FtsZ ring (Z ring) formation at cell poles. MinC has two domains, MinCn and MinCc, which both bind to FtsZ and act synergistically to in...
  18. Asymmetric constriction of dividing Escherichia coli cells induced by expression of a fusion between two min proteins.

    Journal of Bacteriology 196(11):2089 (2014) PMID 24682325 PMCID PMC4010982

    The Min system, consisting of MinC, MinD, and MinE, plays an important role in localizing the Escherichia coli cell division machinery to midcell by preventing FtsZ ring (Z ring) formation at cell poles. MinC has two domains, MinCn and MinCc, which both bind to FtsZ and act synergistically to in...
  19. Asymmetric constriction of dividing Escherichia coli cells induced by expression of a fusion between two min proteins.

    Journal of Bacteriology 196(11):2089 (2014) PMID 24682325 PMCID PMC4010982

    The Min system, consisting of MinC, MinD, and MinE, plays an important role in localizing the Escherichia coli cell division machinery to midcell by preventing FtsZ ring (Z ring) formation at cell poles. MinC has two domains, MinCn and MinCc, which both bind to FtsZ and act synergistically to in...
  20. The highly conserved MraZ protein is a transcriptional regulator in Escherichia coli.

    Journal of Bacteriology 196(11):2053 (2014) PMID 24659771 PMCID PMC4010979

    The mraZ and mraW genes are highly conserved in bacteria, both in sequence and in their position at the head of the division and cell wall (dcw) gene cluster. Located directly upstream of the mraZ gene, the Pmra promoter drives the transcription of mraZ and mraW, as well as many essential cell d...