Abstract:
:Phase variation is important in bacterial pathogenesis, since it generates antigenic variation for the evasion of immune responses and provides a strategy for quick adaptation to environmental changes. In this study, a Helicobacter pylori clone, designated MOD525, was identified that displayed phase-variable lacZ expression. The clone contained a transcriptional lacZ fusion in a putative type III DNA methyltransferase gene (mod, a homolog of the gene JHP1296 of strain J99), organized in an operon-like structure with a putative type III restriction endonuclease gene (res, a homolog of the gene JHP1297), located directly upstream of it. This putative type III restriction-modification system was common in H. pylori, as it was present in 15 out of 16 clinical isolates. Phase variation of the mod gene occurred at the transcriptional level both in clone MOD525 and in the parental H. pylori strain 1061. Further analysis showed that the res gene also displayed transcriptional phase variation and that it was cotranscribed with the mod gene. A homopolymeric cytosine tract (C tract) was present in the 5' coding region of the res gene. Length variation of this C tract caused the res open reading frame (ORF) to shift in and out of frame, switching the res gene on and off at the translational level. Surprisingly, the presence of an intact res ORF was positively correlated with active transcription of the downstream mod gene. Moreover, the C tract was required for the occurrence of transcriptional phase variation. Our finding that translation and transcription are linked during phase variation through slipped-strand mispairing is new for H. pylori.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
de Vries N,Duinsbergen D,Kuipers EJ,Pot RG,Wiesenekker P,Penn CW,van Vliet AH,Vandenbroucke-Grauls CM,Kusters JGdoi
10.1128/jb.184.23.6615-6624.2002keywords:
subject
Has Abstractpub_date
2002-12-01 00:00:00pages
6615-23issue
23eissn
0021-9193issn
1098-5530journal_volume
184pub_type
杂志文章abstract::A strain of Escherichia coli with a mutation in the promoter proximal gene ( uncI ) of the unc operon has been constructed by using a new gene replacement method. The mutation is a deletion of a defined sequence of 196 base pairs. It was constructed by homologous integration and segregation of a ColE1-derived recombin...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.158.3.820-825.1984
更新日期:1984-06-01 00:00:00
abstract::A novel mutant of the marine oil-degrading bacterium Alcanivorax borkumensis SK2, containing a mini-Tn5 transposon disrupting a "tesB-like" acyl-coenzyme A (CoA) thioesterase gene, was found to hyperproduce polyhydroxyalkanoates (PHA), resulting in the extracellular deposition of this biotechnologically important poly...
journal_title:Journal of bacteriology
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doi:10.1128/JB.01321-06
更新日期:2006-12-01 00:00:00
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journal_title:Journal of bacteriology
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doi:10.1128/jb.176.19.5999-6006.1994
更新日期:1994-10-01 00:00:00
abstract::Deibel, R. H. (American Meat Institute Foundation, Chicago, Ill.). Hydrolysis of proteins and nucleic acids by Lancefield group A and other streptococci. J. Bacteriol. 86:1270-1274. 1963.-Classically, group A streptococci have been considered to be nonproteolytic in spite of the observation that a proteinase is produc...
journal_title:Journal of bacteriology
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doi:10.1128/JB.86.6.1270-1274.1963
更新日期:1963-12-01 00:00:00
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journal_title:Journal of bacteriology
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更新日期:2016-11-04 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.120.2.608-617.1974
更新日期:1974-11-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.124.3.1077-1083.1975
更新日期:1975-12-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.150.3.1244-1251.1982
更新日期:1982-06-01 00:00:00
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journal_title:Journal of bacteriology
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更新日期:1989-01-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.85.2.382-393.1963
更新日期:1963-02-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1992-09-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1969-03-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.172.12.6841-6848.1990
更新日期:1990-12-01 00:00:00
abstract::Anabaenopeptins (AP) are bioactive cyclic hexapeptides synthesized nonribosomally in cyanobacteria. APs are characterized by several conserved motifs, including the ureido bond, N-methylation in position 5, and d-Lys in position 2. All other positions of the AP molecule are variable, resulting in numerous structural v...
journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:2011-08-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.123.1.187-195.1975
更新日期:1975-07-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.183.2.800-803.2001
更新日期:2001-01-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1996-05-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:2009-10-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1970-09-01 00:00:00
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更新日期:2007-06-01 00:00:00
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更新日期:2003-05-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1985-11-01 00:00:00
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pub_type: 杂志文章
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更新日期:2001-04-01 00:00:00
abstract::Harvey, R. J. (University of California, Davis) and E. B. Collins. Citrate transport system of Streptococcus diacetilactis. J. Bacteriol. 83:1005-1009. 1962.-The uptake of citrate by Streptococcus diacetilactis is mediated by a transport system that was distinguished from passive diffusion by inducibility and kinetics...
journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1962-05-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1987-01-01 00:00:00
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pub_type: 杂志文章
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更新日期:1972-09-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1983-02-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1987-08-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
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更新日期:1994-04-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00711-19
更新日期:2020-03-11 00:00:00