Abstract：
:An essential early event in Shigella and Salmonella pathogenesis is invasion of non-phagocytic intestinal epithelial cells. Pathogen entry is triggered by the delivery of multiple bacterial effector proteins into target mammalian cells. The Shigella invasion plasmid antigen B (IpaB), which inserts into the host plasma membrane, is required for effector delivery and invasion. To investigate the biochemical properties and membrane topology of IpaB, we purified the native full-length protein following expression in laboratory Escherichia coli. Purified IpaB assembled into trimers via an N-terminal domain predicted to form a trimeric coiled-coil, and is predominantly alpha-helical. Upon lipid interaction, two transmembrane domains (residues 313-333 and 399-419) penetrate the bilayer, allowing the intervening hydrophilic region (334-398) to cross the membrane. Purified IpaB integrated into model, erythrocyte and mammalian cell membranes without disrupting bilayer integrity, and induced liposome fusion in vitro. An IpaB-derived 162 residue alpha-helical polypeptide (IpaB(418-580)) is a potent inhibitor of IpaB-directed liposome fusion in vitro and blocked Shigella entry into cultured mammalian cells at 10(-8) M. It is also a heterologous inhibitor of Salmonella invasion protein B (SipB) activity and Salmonella entry. In contrast, IpaB(418-580) failed to prevent the contact-dependent haemolytic activity of Shigella. These findings question the proposed direct link between contact-dependent haemolysis and Shigella entry, and demonstrate that IpaB and SipB share biochemical properties and membrane topology, consistent with a conserved mode of action during cell entry.
journal_name
Mol Microbioljournal_title
Molecular microbiologyauthors
Hume PJ,McGhie EJ,Hayward RD,Koronakis Vdoi
10.1046/j.1365-2958.2003.03559.xsubject
Has Abstractpub_date
2003-07-01 00:00:00pages
425-39issue
2eissn
0950-382Xissn
1365-2958pii
3559journal_volume
49pub_type
杂志文章abstract：:The bacterium Streptomyces davaonensis produces the antibiotic roseoflavin, which is a riboflavin (vitamin B2 ) analog. The key enzyme of roseoflavin biosynthesis is the 8-demethyl-8-amino-riboflavin-5'-phosphate (AFP) synthase RosB which synthesizes AFP from riboflavin-5'-phosphate. AFP is not a substrate for the las...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.14567
更新日期：2020-10-01 00:00:00
abstract：:RbpA is an RNA polymerase-binding protein that occurs in the actinomycete family of bacteria and is regulated by the disulphide stress-response sigma factor, sigma(R), in Streptomyces coelicolor. Here we demonstrate that rbpA null mutants exhibit a slow-growth phenotype and are particularly sensitive to the transcript...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2006.05116.x
更新日期：2006-05-01 00:00:00
abstract：:Photorhabdus are bacteria found colonizing the gut of a specialized stage of the nematode Heterorhabditis, called the infective juvenile (IJ). The IJ is a free-living stage of the nematode that seeks out and infects insect larvae. Once inside the insect the IJ release Photorhabdus into the haemolymph where the bacteri...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2005.04574.x
更新日期：2005-05-01 00:00:00
abstract：:In the mouse model for systemic infection, natural a/alpha strains of C. albicans are more virulent and more competitive than their spontaneous MTL-homozygous offspring, which arise primarily by loss of one chromosome 5 homologue followed by duplication of the retained homologue (uniparental disomy). Deletion of eithe...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2007.05759.x
更新日期：2007-06-01 00:00:00
abstract：:PilO of Pseudomonas aeruginosa 1244 catalyses the attachment of an O-antigen repeating unit to the beta-carbon of the pilin C-terminal residue, a serine. The present study was conducted to locate the regions of this enzyme important in catalysis and to establish the cellular location of the pilin glycosylation reactio...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2007.06001.x
更新日期：2007-12-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.14111
更新日期：2018-11-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2010.07520.x
更新日期：2011-03-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1992.tb01369.x
更新日期：1992-07-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2001.02553.x
更新日期：2001-08-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1994.tb01311.x
更新日期：1994-11-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2005.04799.x
更新日期：2005-09-01 00:00:00
abstract：:A new locus required for type 4 pilus biogenesis by Pseudomonas aeruginosa has been identified. A pilE mutant, designated MJ-6, was broadly resistant to pili-specific phages and unable to translocate across solid surfaces by the pilus-dependent mechanism of twitching motility (Twt-). Immunoblot analysis demonstrated t...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1994.tb00489.x
更新日期：1994-09-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2000.01940.x
更新日期：2000-06-01 00:00:00
abstract：:Quorum-sensing control of luminescence in Vibrio harveyi, which involves an indirect autoinducer-mediated phosphorelay signal transduction system, contrasts with the prototypical quorum-sensing system of Vibrio fischeri, in which the autoinducer and the transcriptional activator LuxR directly activate lux operon expre...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2003.03453.x
更新日期：2003-04-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1988.tb00058.x
更新日期：1988-07-01 00:00:00
abstract：:Protein kinase G of Mycobacterium tuberculosis has been implicated in virulence and in regulation of glutamate metabolism. Here we show that this kinase undergoes a pattern of autophosphorylation that is distinct from that of other M. tuberculosis protein kinases characterized to date and we identify GarA as a substra...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2008.06489.x
更新日期：2008-12-01 00:00:00
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pub_type： 杂志文章
doi：10.1111/j.1365-2958.2009.06846.x
更新日期：2009-09-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2006.05552.x
更新日期：2007-02-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2004.04321.x
更新日期：2004-10-01 00:00:00
abstract：:Crop destruction by the hemibiotrophic rice pathogen Magnaporthe oryzae requires plant defence suppression to facilitate extensive biotrophic growth in host cells before the onset of necrosis. How this is achieved at the genetic level is not well understood. Here, we report that a M. oryzae sirtuin, MoSir2, plays an e...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/mmi.12743
更新日期：2014-10-01 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：2011-01-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1994.tb00451.x
更新日期：1994-08-01 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：2012-08-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1046/j.1365-2958.2003.03261.x
更新日期：2003-01-01 00:00:00
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journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2008.06334.x
更新日期：2008-08-01 00:00:00
abstract：:Bordetella bronchiseptica is a pathogen that can acquire iron using its native alcaligin siderophore system, but can also use the catechol xenosiderophore enterobactin via the BfeA outer membrane receptor. Transcription of bfeA is positively controlled by a regulator that requires induction by enterobactin. Catecholam...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2012.08032.x
更新日期：2012-05-01 00:00:00
abstract：:In Escherichia coli, bulky DNA lesions are repaired primarily by nucleotide excision repair (NER). Unrepaired lesions encountered by DNA polymerase at the replication fork create a blockage which may be relieved through RecF-dependent recombination. We have designed an assay to monitor the different mechanisms through...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2007.05790.x
更新日期：2007-07-01 00:00:00
abstract：:The kinetics of initiation of chromosome replication after induction of DnaA protein synthesis was studied in a dnaA(nuII) rnh mutant of Escherichia coli. DnaA protein synthesis was induced to different extents using the wild-type dnaA gene controlled by a lac promoter. Initiation of chromosome replication from oriC, ...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1995.tb02229.x
更新日期：1995-01-01 00:00:00
abstract：:Sigma28 controls the expression of flagella-related genes and is the most widely distributed alternative sigma factor, present in motile Gram-positive and Gram-negative bacteria. The distinguishing feature of sigma28 promoters is a long -10 region (GCCGATAA). Despite the fact that the upstream GC is highly conserved, ...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.2009.06691.x
更新日期：2009-05-01 00:00:00
abstract：:The H-NS protein of enteric bacteria is one of the major proteins of the bacterial nucleoid and seems to play an important role in nucleoid structure. Transcription of the hns gene encoding the H-NS protein appears to be negatively regulated by H-NS itself both in vitro and in vivo. We have examined the role of this m...
journal_title：Molecular microbiology
pub_type： 杂志文章
doi：10.1111/j.1365-2958.1995.mmi_18010101.x
更新日期：1995-10-01 00:00:00
