Figure 2.

 Cell cycle expression of ftsZ. Swarmer cells of strain NA1000 harboring ftsZ–lacZ fusion plasmid plac290/HB2.0BP were collected by density centrifugation and were allowed to proceed through the cell cycle. Cell division occurred at 150 min (1 cell division unit). From the same synchronized culture, aliquots were taken at the times indicated and were either pulse-labeled with [³⁵S]methionine to follow protein synthesis, labeled with [8-³H]GTP to follow DNA synthesis, immunoblotted with anti-FtsZ antibody, or used for photomicroscopy. (A) Plot of the relative rates of β-galactosidase (♦) synthesis as measured by phosphorimaging, DNA replication (▪) as measured by incorporation of [8-³H]GTP into DNA, and FtsZ concentration (▵) as measured by densitometric scanning of immunoblots revealed by chemiluminescence. (B) Autoradiograms from the immunoprecipitation of β-galactosidase (β-gal), flagellins (Fla), and immunoblot with anti-FtsZ antibody (FtsZ western). (C) Photomicrographs of cells at different stages of the cell cycle.