Abstract：
:Chromosomes are divided into topologically independent regions, called domains, by the action of uncharacterized barriers. With the goal of identifying domain barrier components, we designed a genetic selection for mutants with reduced negative supercoiling of the Escherichia coli chromosome. We employed a strain that contained two chromosomally located reporter genes under the control of a supercoiling-sensitive promoter and used transposon mutagenesis to generate a wide range of mutants. We subjected the selected mutants to a series of secondary screens and identified five proteins as modulators of chromosomal supercoiling in vivo. Three of these proteins: H-NS, Fis and DksA, have clear ties to chromosome biology. The other two proteins, phosphoglucomutase (Pgm) and transketolase (TktA), are enzymes involved in carbohydrate metabolism and have not previously been shown to affect DNA. Deletion of any of the identified genes specifically affected chromosome topology, without affecting plasmid supercoiling. We suggest that at least H-NS, Fis and perhaps TktA assist directly in the supercoiling of domains by forming topological barriers on the E. coli chromosome.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Hardy CD,Cozzarelli NRdoi
10.1111/j.1365-2958.2005.04799.xsubject
Has Abstractpub_date
2005-09-01 00:00:00pages
1636-52issue
6eissn
0950-382Xissn
1365-2958pii
MMI4799journal_volume
57pub_type
杂志文章abstract：:Urinary tract infection (UTI) is a very common extraintestinal infection, and Escherichia coli is by far the most common causative organism. Uropathogenic E. coli possess traits that distinguish them from commensal strains of E. coli, such as secretion systems that allow virulence factors to be targeted to extracytopl...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2000.02110.x
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journal_title：Molecular microbiology
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doi：
更新日期：1988-01-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2003.03543.x
更新日期：2003-07-01 00:00:00
abstract：:Two operons, comAB and comCDE, play a key role in the co-ordination of spontaneous competence development in cultures of Streptococcus pneumoniae. ComAB is required for export of the comC-encoded competence-stimulating peptide (CSP). Upon CSP binding, the histidine kinase ComD activates ComE, its cognate response regu...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2000.02187.x
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.13988
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2000.01679.x
更新日期：2000-01-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
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journal_title：Molecular microbiology
pub_type： 杂志文章,评审
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更新日期：2018-01-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.13270
更新日期：2016-03-01 00:00:00
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更新日期：1999-10-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1994.tb00387.x
更新日期：1994-03-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.12688
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journal_title：Molecular microbiology
pub_type： 杂志文章
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更新日期：2004-09-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1992.tb01560.x
更新日期：1992-05-01 00:00:00
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pub_type： 杂志文章
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更新日期：2000-05-01 00:00:00
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pub_type： 杂志文章,评审
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更新日期：2003-05-01 00:00:00
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更新日期：2007-10-01 00:00:00
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pub_type： 杂志文章
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更新日期：2006-08-01 00:00:00
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更新日期：2008-10-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章,评审
doi：10.1111/j.1365-2958.1995.tb02404.x
更新日期：1995-05-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
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更新日期：1990-06-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
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更新日期：2006-01-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
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更新日期：2007-08-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
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更新日期：2012-10-01 00:00:00
abstract：:Sequence-inherent targeting information directs polypeptides synthesized in the cytosol to their respective cellular compartment. Some proteins use ambiguous sorting signals or specific folding properties to be dually distributed between the cytosol and mitochondria. A study published in this issue of Molecular Microb...
journal_title：Molecular microbiology
pub_type： 评论,杂志文章
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更新日期：2009-04-01 00:00:00
