Abstract:
:A series of recombinant plasmids was generated in Escherichia coli in which the TEM beta-lactamase translocon (TnA) was inserted into the small plasmid RSF1010. RSF1010 is a 5.5 X 10(6) dalton nonconjugative plasmid which confers resistance to streptomycin and sulfonamide. The recombinant plasmids can be classified into three clearly defined phenotypic groups. Group I is ampicillin-, streptomycin- and sulfonamide-resistant. Group II is ampicillin- and sulfonamide-resistant but has lost streptomycin resistance. Group III is ampicillin-resistant but is sensitive to sulfonamide and shows a simultaneous 30-fold reduction in the minimal inhibitory concentration of streptomycin. It was possible to map the site of insertion of TnA within RSF1010 by electron microscope studies of DNA heteroduplexes formed between RSF1010 and recombinant plasmids. Insertions of TnA occur at, at least, 12 distinct sites in a region corresponding to one-third of the RSF1010 DNA molecule. Those insertions giving rise to particular phenotypes are clustered. Insertions of TnA-like insertion sequences (IS) appear to give rise to strongly polar mutations.
journal_name
Proc Natl Acad Sci U S Aauthors
Heffron F,Rubens C,Falkow Sdoi
10.1073/pnas.72.9.3623keywords:
subject
Has Abstractpub_date
1975-09-01 00:00:00pages
3623-7issue
9eissn
0027-8424issn
1091-6490journal_volume
72pub_type
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1986-02-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1983-09-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1915806117
更新日期:2020-02-18 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.84.12.4126
更新日期:1987-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1811589116
更新日期:2019-02-19 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0705195104
更新日期:2007-07-24 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1306899110
更新日期:2013-06-04 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.12.4028
更新日期:1985-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.86.13.4953
更新日期:1989-07-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.82.4.1199
更新日期:1985-02-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1995-11-07 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2004-12-28 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.77.7.4113
更新日期:1980-07-01 00:00:00
abstract::Mammalian thalamus is a critical site where early perception of sensorimotor signals is dynamically regulated by acetylcholine in a behavioral state-dependent manner. In this study, we examined how synaptic transmission is modulated by acetylcholine in auditory thalamus where sensory relay neurons form parallel lemnis...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0304445101
更新日期:2004-01-06 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.95.12.6669
更新日期:1998-06-09 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1520099112
更新日期:2015-12-29 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0905825106
更新日期:2009-08-11 00:00:00
abstract::We studied the abundance and structure of globin mRNAs present in K562 cells both before and after induction of hemoglobin synthesis by hemin. In vitro translation of poly(A)+ RNA from K562 cells generated protein products corresponding to alpha, A gamma-, G gamma-, epsilon-, and zeta-globin mRNAs. Individual globin m...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.80.18.5515
更新日期:1983-09-01 00:00:00
abstract::Various enzymatic derivatives of the murine myeloma protein IgA(MOPC-315) were subjected to hapten-binding quantitation and circular dichroic analysis in an attempt to ascertain the structural localization and functional definition of the immunoglobulin active site. The extrinsic Cotton effects observed with near satu...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.71.5.1940
更新日期:1974-05-01 00:00:00
abstract::We have compared the process of prophage lambda induction with that of prophage Mu. According to the Campbell model, rescue of lambda DNA from the host DNA involves reversal of lambda integration such that the prophage DNA is excised from the host chromosome. We have monitored this event by locating the prophage DNA w...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.74.8.3143
更新日期:1977-08-01 00:00:00