Abstract:
:A method of insertional mutagenesis for naturally transformable organisms has been adapted from Haemophilus influenzae and applied to the study of the pathogenesis of Campylobacter jejuni. A series of kanamycin-resistant insertional mutants of C. jejuni 81-176 has been generated and screened for loss of ability to invade INT407 cells. Eight noninvasive mutants were identified which showed 18-200-fold reductions in the level of invasion compared with the parent. Three of these eight show defects in motility, and five are fully motile. The three mutants with motility defects were further characterized to evaluate the method. One mutant, K2-32, which is non-adherent and non-invasive, has an insertion of the kanamycin-resistance cassette into the flaA flagellin gene and has greatly reduced motility and a truncated flagellar filament typical of flaA mutants. The adherent non-invasive mutants K2-37 and K2-55 are phenotypically paralysed, i.e. they have a full-length flagellar filament but are non-motile. All three mutants show an aberration in flagellar structure at the point at which the filament attaches to the cell. Mutants K2-37 and K2-55 represent overlapping deletions affecting the same gene, termed pflA (paralysed flagella). This gene encodes a predicted protein of 788 amino acid residues and a molecular weight of 90,977 with no significant homology to known proteins. Site-specific insertional mutants into this open reading frame result in the same paralysed flagellar phenotype and the same invasion defects as the original mutants. The differences in adherence between the two classes of flagellar mutant suggest that flagellin can serve as a secondary adhesion, although other adhesins mediate a motility-dependent internalization process. Characterization of the mutants at the molecular level and in animal models should further contribute to our understanding of the pathogenicity of these organisms.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Yao R,Burr DH,Doig P,Trust TJ,Niu H,Guerry Pdoi
10.1111/j.1365-2958.1994.tb01324.xsubject
Has Abstractpub_date
1994-12-01 00:00:00pages
883-93issue
5eissn
0950-382Xissn
1365-2958journal_volume
14pub_type
杂志文章abstract::The cer-Xer dimer resolution system of plasmid ColE1 is highly selective, acting only at sites on the same molecule and in direct repeat. Recombination requires the XerCD recombinase and accessory proteins ArgR and PepA. The Escherichia coli chromosome dimer resolution site dif and the type II hybrid site use the same...
journal_title:Molecular microbiology
pub_type: 杂志文章
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更新日期:1996-05-01 00:00:00
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更新日期:2010-03-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2014-05-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章,评审
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更新日期:1993-08-01 00:00:00
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pub_type: 杂志文章
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更新日期:2007-03-01 00:00:00
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更新日期:1999-02-01 00:00:00
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pub_type: 杂志文章
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更新日期:2009-10-01 00:00:00
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pub_type: 杂志文章
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更新日期:1989-06-01 00:00:00
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pub_type: 杂志文章
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更新日期:1995-07-01 00:00:00
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pub_type: 杂志文章
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更新日期:2000-07-01 00:00:00
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pub_type: 杂志文章
doi:10.1111/mmi.13078
更新日期:2015-09-01 00:00:00
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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:2001-03-01 00:00:00
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更新日期:2008-08-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2000-08-01 00:00:00
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更新日期:2007-03-01 00:00:00
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journal_title:Molecular microbiology
pub_type: 杂志文章
doi:10.1111/j.1365-2958.1994.tb00327.x
更新日期:1994-02-01 00:00:00
abstract::The GATA factor AreA is a wide-domain regulator in Aspergillus nidulans with transcriptional activation and chromatin remodelling functions. AreA interacts with the nitrate-specific Zn(2)-C(6) cluster protein NirA and both proteins cooperate to synergistically activate nitrate-responsive genes. We have previously esta...
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,评审
doi:10.1111/j.1365-2958.1995.mmi_18020201.x
更新日期:1995-10-01 00:00:00