Premium
Use of time‐lapse microscopy to visualize rapid movement of the replication origin region of the chromosome during the cell cycle in Bacillus subtilis
Author(s) -
Webb Chris D.,
Graumann Peter L.,
Kahana Jason A.,
Teleman Aurelio A.,
Silver Pamela A.,
Losick Richard
Publication year - 1998
Publication title -
molecular microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.857
H-Index - 247
eISSN - 1365-2958
pISSN - 0950-382X
DOI - 10.1046/j.1365-2958.1998.00808.x
Subject(s) - biology , lac repressor , bacillus subtilis , mitosis , cell cycle , chromosome , fluorescence microscope , condensin , origin of replication , microbiology and biotechnology , dna , chromosome segregation , dna replication , genetics , cell , fluorescence , gene , lac operon , plasmid , bacteria , physics , quantum mechanics
We describe the use of time‐lapse fluorescence microscopy to visualize the movement of the DNA replication origin and terminus regions on the Bacillus subtilis chromosome during the course of the cell cycle. The origin and terminus regions were tagged with a cassette of tandem lac operator repeats and visualized through the use of a fusion of the green fluorescent protein to the LacI repressor. We have discovered that origin regions abruptly move apart towards the cell poles during a brief interval of the cell cycle. This movement was also seen in the absence of cell wall growth and in the absence of the product of the parB homologue spo0J . The origin regions moved apart an average distance of 1.4 μm in an 11 min period of abrupt movement, representing an average velocity of 0.17 μm min −1 . and reaching a maximum velocity of greater than 0.27 μm min −1 . The terminus region also exhibited a striking pattern of movement but not as far or a rapid as the origin region. These results provide evidence for a mitotic‐like motor that is responsible for segregation of the origin regions of the chromosomes.