The structure and function of the bacterial chromosome

Current Opinion in Genetics and Development

Volumn 15, Issue 2, 2005, Pages 153-162

  Thanbichler, Martin ^a   Viollier, Patrick H ^b   Shapiro, Lucy ^a  

^a STANFORD UNIVERSITY   (United States)

^b CASE WESTERN RESERVE UNIVERSITY SCHOOL OF MEDICINE   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ADENOSINE TRIPHOSPHATE; BACTERIAL DNA; BACTERIAL RNA; DNA TOPOISOMERASE; INTEGRATION HOST FACTOR; RNA POLYMERASE;

BACILLUS SUBTILIS; BACTERIAL CELL; BACTERIAL CHROMOSOME; CARBOXY TERMINAL SEQUENCE; CAULOBACTER CRESCENTUS; CELL CYCLE; CHROMOSOME DUPLICATION; CHROMOSOME STRUCTURE; CYTOLOGY; DNA BINDING; DNA CLEAVAGE; DNA DAMAGE; DNA HELIX; DNA MICROARRAY; DNA REPLICATION; DNA STRAND; DNA SUPERCOILING; ESCHERICHIA COLI; EUKARYOTE; FLUORESCENCE IN SITU HYBRIDIZATION; GENE FUNCTION; GENE SEGREGATION; GENETIC ORGANIZATION; GENETIC TRANSCRIPTION; HYDROLYSIS; MICROSCOPY; MOLECULAR DYNAMICS; NONHUMAN; POLYMERIZATION; PRIORITY JOURNAL; PROTEIN DOMAIN; REVIEW; SALMONELLA TYPHIMURIUM; SYNTHESIS;

EID: 15744376527     PISSN: 0959437X     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.gde.2005.01.001     Document Type: Review

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88. Gitai Z, Dye NA, Reisenauer A, Wachi M, Shapiro L: MreB actin-mediated segregation of a specific region of a bacterial chromosome. Cell 2005 120: article in press. This study demonstrates that the MreB cytoskeleton is directly involved in the rapid pole-ward movement of newly replicated origin regions in C. crescentus. The authors first characterize a novel antibiotic, named A22. They show that all stains obtained from a screen for A22 resistant cells carry mutations in MreB that map close to the ATP-binding pocket of the protein. Exposure of C. crescentus to the drug causes nearly instantaneous disassembly of the MreB spiral. This effect is rapidly reversed after transfer of the cells into A22-free medium, making the compound a valuable tool for the study of MreB function. In cells treated with A22, DNA replication initiates and proceeds normally, but the newly duplicated origin regions are not separated. However, if A22 is removed from the medium later in S-phase, immediate and rapid segregation of the origins is observed, which indicates the necessity of a functional MreB spiral for this process to occur. By contrast, A22 does not affect segregation of other chromosomal loci, if added after separation of the origin regions. The authors, therefore, conclude that different mechanisms might act in a sequential manner to drive bacterial chromosome segregation.