Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The nucleoid occlusion factor Noc controls DNA replication initiation in Staphylococcus aureus [ChIP-Seq]

ABSTRACT: Successive division events in the spherically shaped bacterium Staphylococcus aureus are oriented in three alternating perpendicular planes. The mechanisms that underlie this relatively unique pattern of division and coordinate it with chromosome segregation remain largely unknown. Thus far, the only known spatial regulator of division in this organism is the nucleoid occlusion protein Noc that inhibits assembly of the cytokinetic ring over the chromosome. However, Noc is not essential in S. aureus, indicating that additional regulators are likely to exist. To search for these factors, we screened for mutants that are synthetic lethal with Noc inactivation. Our characterization of these mutants led to the discovery that S. aureus Noc also controls the initiation of DNA replication. We show that cells lacking Noc over-initiate and mutations in the initiator gene dnaA suppress this defect. Importantly, these dnaA mutations also partially suppress the division problems associated with ∆noc. Reciprocally, we show that over-expression of DnaA enhances the over-initiation and cell division phenotypes of cells lacking Noc. Thus, a single factor both blocks cell division over chromosomes and helps to ensure that new rounds of DNA replication are not initiated prematurely. This degree of economy in coordinating key cell biological processes has not been observed in rod-shaped bacteria and may reflect the challenges posed by the reduced cell volume and complicated division pattern of this spherical pathogen.

ORGANISM(S): Bacillus subtilis PY79 Staphylococcus aureus subsp. aureus NCTC 8325

PROVIDER: GSE93264 | GEO | 2017/08/31

SECONDARY ACCESSION(S): PRJNA360436

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Dataset's files

Source:

			Action	DRS
		Other

Items per page:

1 - 1 of 1

Similar Datasets

The nucleoid occlusion factor Noc controls DNA replication initiation in Staphylococcus aureus [WGS-Seq]

Project description:Successive division events in the spherically shaped bacterium Staphylococcus aureus are oriented in three alternating perpendicular planes. The mechanisms that underlie this relatively unique pattern of division and coordinate it with chromosome segregation remain largely unknown. Thus far, the only known spatial regulator of division in this organism is the nucleoid occlusion protein Noc that inhibits assembly of the cytokinetic ring over the chromosome. However, Noc is not essential in S. aureus, indicating that additional regulators are likely to exist. To search for these factors, we screened for mutants that are synthetic lethal with Noc inactivation. Our characterization of these mutants led to the discovery that S. aureus Noc also controls the initiation of DNA replication. We show that cells lacking Noc over-initiate and mutations in the initiator gene dnaA suppress this defect. Importantly, these dnaA mutations also partially suppress the division problems associated with ∆noc. Reciprocally, we show that over-expression of DnaA enhances the over-initiation and cell division phenotypes of cells lacking Noc. Thus, a single factor both blocks cell division over chromosomes and helps to ensure that new rounds of DNA replication are not initiated prematurely. This degree of economy in coordinating key cell biological processes has not been observed in rod-shaped bacteria and may reflect the challenges posed by the reduced cell volume and complicated division pattern of this spherical pathogen.

2017-08-31 | GSE100776 | GEO

The nucleoid occlusion factor Noc controls DNA replication initiation in Staphylococcus aureus [Tn-seq]

2017-08-31 | GSE101335 | GEO

Chromatin immunoprecipitation of Bacillus subtilis to identify Noc protein binding sites

Project description:Coordination of chromosome segregation and cytokinesis is crucial for efficient cell proliferation. In Bacillus subtilis the nucleoid occlusion protein Noc protects chromosomes by associating with the chromosome and preventing cell division in its vicinity. Using protein localization, ChAP-on-Chip and bioinformatics, we have identified a consensus Noc-binding DNA sequence (NBS), and show that Noc is targeted to about 70 discrete regions scattered around the chromosome, though absent from a large region around the replication terminus. Purified Noc bound specifically to an NBS in vitro. NBSs inserted near the replication terminus bound Noc-YFP and caused a delay in cell division. An autonomous plasmid carrying an NBS recruited Noc-YFP and conferred a severe Noc-dependent inhibition of cell division. This shows that Noc is a potent inhibitor of division but that its activity is strictly localized by interaction with NBS sites in vivo. We propose that Noc not only serves as a spatial regulator of cell division to protect the nucleoid, but also a timing device with an important role in the co-ordination of chromosome segregation and cell division.

2009-07-01 | E-MEXP-2133 | biostudies-arrayexpress

Exposure of microaerobic Campylobacter jejuni to 10 micromolar NOC-5 & NOC-7

Project description:Two batch cultures of Wild-type C. jejuni NCTC 11168 were grown in 100 ml volumes of Mueller-Hinton broth in 250 ml baffled flasks. Microaerophilic conditions were generated using a MACS-VA500 microaerophilic work station (10 % Oxygen, 10 % Carbon dioxide, 80 % Nitrogen) from Don Whitley Scientific, Ltd which also maintained the growth temperature at 42 ºC. When mid-exponential phase was reached 0.010 mM NOC-5 & NOC-7 was added to one of the cultures. After a 15 minute exposure samples of both treated and untreated cells were harvested into phenol/ethanol to stabilize the RNA and total RNA was purified using Qiagen’s RNeasy Mini kit (as recommended by the suppliers) prior to use in microarray analysis.

2012-05-23 | GSE38114 | GEO

Exposure of oxygen limited Campylobacter jejuni to 10 micromolar NOC-5 & NOC-7

Project description:Batch cultures of Wild-type C. jejuni NCTC 11168 were grown in 200 ml volumes of Mueller-Hinton broth in 250 ml baffled flasks. Microaerophilic conditions were generated using a MACS-VA500 microaerophilic work station (10 % Oxygen, 10 % Carbon dioxide, 80 % Nitrogen) from Don Whitley Scientific, Ltd which also maintained the growth temperature at 42 ºC. When mid-exponential phase was reached 0.010 mM NOC-5 & NOC-7 was added to one of the cultures. After a 15 minute exposure samples of both treated and untreated cells were harvested into phenol/ethanol to stabilize the RNA and total RNA was purified using Qiagen’s RNeasy Mini kit (as recommended by the suppliers) prior to use in microarray analysis.

2012-05-23 | GSE38115 | GEO

Regulatory elements coordinating initiation of chromosome replication to the Escherichia coli cell cycle

Project description:Escherichia coli coordinates replication and division cycles by initiating replication at a narrow range of cell sizes. By tracking replisomes in individual cells through thousands of division cycles in wild-type and mutant strains, we were able to compare the relative importance of previously described control systems. We found that accurate triggering of initiation does not require synthesis of new DnaA. The initiation size increased only marginally as DnaA was diluted by growth after dnaA expression had been turned off. This suggests that the conversion of DnaA between its active ATP- and inactive ADP-bound states is more important for initiation size control than the total free concentration of DnaA. In addition, we found that the known ATP/ADP-converters DARS and datA compensate for each other, although the removal of them makes the initiation size more sensitive to the concentration of DnaA. Only disruption of the regulatory inactivation of DnaA (RIDA) mechanism had a radical impact on replication initiation. This result was corroborated by the finding that termination of one round of replication correlates with the next initiation at intermediate growth rates, as would be the case if RIDA-mediated conversion from DnaA-ATP to DnaA-ADP abruptly stops at termination and DnaA-ATP starts accumulating.

2023-05-12 | PXD036580 | Pride

Transcription profiling of anaerobic transcriptional response of E.coli MG1655 to NO released from NOC compounds

Project description:The transcriptional response of Escherichia coli MG1655 to NO released from NOC-5 and NOC-7 under anerobic conditions in contiuous chemostat culture on chemically defined minimal media

2006-01-14 | E-MEXP-248 | biostudies-arrayexpress

The nucleoid occlusion factor Noc controls DNA replication initiation in Staphylococcus aureus

Project description:The nucleoid occlusion factor Noc controls DNA replication initiation in Staphylococcus aureus

| PRJNA393025 | ENA

Transcription profiling of Escherichia coli strain MG1655 response to NO released from NOC compounds

Project description:Escherichia coli strain MG1655 response to NO released from NOC compounds. Under contiuous steady state chemostat conditions, in chemically defined media.

2006-01-12 | E-MEXP-246 | biostudies-arrayexpress

The nucleoid occlusion factor Noc controls DNA replication initiation in Staphylococcus aureus [ChIP-Seq]

Project description:The nucleoid occlusion factor Noc controls DNA replication initiation in Staphylococcus aureus [ChIP-Seq]

| PRJNA360436 | ENA