Abstract:
:DNA helicase I, encoded on the Escherichia coli F plasmid, catalyzes a site- and strand-specific nicking reaction within the F plasmid origin of transfer (oriT) to initiate conjugative DNA strand transfer. The product of the nicking reaction contains a single phosphodiester bond interruption as determined by single-nucleotide resolution mapping of both sides of the nick site. This analysis has demonstrated that the nick is located at precisely the same site previously shown to be nicked in vivo (T. L. Thompson, M. B. Centola, and R. C. Deonier, J. Mol. Biol. 207:505-512, 1989). In addition, studies with two oriT point mutants have confirmed the specificity of the in vitro reaction. Characterization of the nicked DNA product has revealed a modified 5' end and a 3' OH available for extension by E. coli DNA polymerase I. Precipitation of nicked DNA with cold KCl in the presence of sodium dodecyl sulfate suggests the existence of protein covalently attached to the nicked DNA molecule. The covalent nature of this interaction has been directly demonstrated by transfer of radiolabeled phosphate from DNA to protein. On the basis of these results, we propose that helicase I becomes covalently bound to the 5' end of the nicked DNA strand as part of the reaction mechanism for phosphodiester bond cleavage. A model is presented to suggest how helicase I could nick the F plasmid at oriT and subsequently unwind the duplex DNA to provide single-stranded DNA for strand transfer during bacterial conjugation.
journal_name
J Bacterioljournal_title
Journal of bacteriologyauthors
Matson SW,Nelson WC,Morton BSdoi
10.1128/jb.175.9.2599-2606.1993subject
Has Abstractpub_date
1993-05-01 00:00:00pages
2599-606issue
9eissn
0021-9193issn
1098-5530journal_volume
175pub_type
杂志文章abstract::In Bacillus thuringiensis, a novel N-acetylmuramoyl-L-alanine amidase gene (named cwlB) was detected, and the CwlB protein was purified and characterized. Reverse transcription-PCR (RT-PCR) results indicated that cwlB and an upstream gene (named cwlA) formed one transcriptional unit. 5' rapid amplification of cDNA end...
journal_title:Journal of bacteriology
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doi:10.1128/JB.00112-13
更新日期:2013-06-01 00:00:00
abstract::Oxolinic acid reduced RNA synthesis rates whether chromosome supercoiling decreased, increased, or remained unchanged. Thus, inhibition of RNA synthesis by oxolinic acid appears to involve factors other than average DNA supercoiling level. Coumermycin A1 caused RNA synthesis rates to increase or decrease roughly in pa...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.155.1.420-423.1983
更新日期:1983-07-01 00:00:00
abstract::Group B streptococcus (GBS) pili may enhance colonization and infection by mediating bacterial adhesion to host cells, invasion across endothelial and epithelial barriers, and resistance to bacterial ingestion and killing by host phagocytes. However, it remains unclear how pilus expression is regulated and how modulat...
journal_title:Journal of bacteriology
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更新日期:2012-05-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.117.3.1141-1148.1974
更新日期:1974-03-01 00:00:00
abstract::A Pediococcus cerevisiae mutant that actively accumulated folate (PteGlu), in contrast to the wild-type, was also found to exhibit changes in the pattern of uptake of 5-methyl-tetrahydrofolate (5-CH3-H4PteGlu) and amethopterin. Most of the 5-CH3-H4PteGlue accumulated through a glucose- and temperature-dependent proces...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.123.2.400-406.1975
更新日期:1975-08-01 00:00:00
abstract::MalT is the central transcriptional activator of all mal genes in Escherichia coli. Its activity is controlled by the inducer maltotriose. It can be inhibited by the interaction with certain proteins, and its expression can be controlled. We report here a novel aspect of mal gene regulation: the effect of cytoplasmic ...
journal_title:Journal of bacteriology
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doi:10.1128/JB.00767-08
更新日期:2009-02-01 00:00:00
abstract::We analyzed 12 individual codons, which differed widely with respect to the frequency of use in Escherichia coli and the abundance of the corresponding tRNAs, for their influence on the coupling between transcription and translation. This was probed by determining the effects of codon substitutions in the leader pepti...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.171.11.5812-5816.1989
更新日期:1989-11-01 00:00:00
abstract::More than 98% of reported human listeriosis cases are caused by Listeria monocytogenes serotypes within lineages I and II. Serotypes within lineage III (4a and 4c) are commonly isolated from environmental and food specimens. We report the first complete genome sequence of a lineage III isolate, HCC23, which will be us...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.05236-11
更新日期:2011-07-01 00:00:00
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pub_type: 杂志文章
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更新日期:2000-06-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.111.2.356-360.1972
更新日期:1972-08-01 00:00:00
abstract::The Lyme disease spirochete Borrelia burgdorferi is unique among bacteria in its large number of lipoproteins that are encoded by a small, exceptionally fragmented, and predominantly linear genome. Peripherally anchored in either the inner or outer membrane and facing either the periplasm or the external environment, ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.00658-16
更新日期:2017-02-28 00:00:00
abstract::The electron transport system of Acinetobacter sp. HO1-N was studied to determine the specific cytochromes and to measure changes in the composition of the respiratory system due to growth in various concentrations of oxygen or types of growth substrates. Spectrophotometric analysis revealed that the quantity and type...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.142.3.859-868.1980
更新日期:1980-06-01 00:00:00
abstract::The activity of beta-glucosidase (EC 3.2.1.21) in extracts of Dictyostelium discoideum was investigated. The specific activity increased early in development, declined during pseudoplasmodium formation, and increased again during sorocarp formation. The beta-glucosidase which was present in growing amoebae and during ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.100.3.1208-1217.1969
更新日期:1969-12-01 00:00:00
abstract::Manohar, M. (University of Minnesota, St. Paul), S. Kumar, and R. K. Lindorfer. Heat reactivation of the alpha-hemolytic, dermonecrotic, and lethal activities of crude and purified staphylococcal alpha-toxin. J. Bacteriol. 91:1681-1685. 1966.-Crude staphylococcal toxin loses its alpha-hemolytic activity more rapidly a...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.91.5.1681-1685.1966
更新日期:1966-05-01 00:00:00
abstract::Gartner, T. K. (University of California, Santa Barbara), and E. Orias. Effects of mutations to streptomycin resistance on the rate of translation of mutant genetic information. J. Bacteriol. 91:1021-1028. 1966.-The effects of mutations to streptomycin resistance of independent origin upon the translation of suppressi...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.91.3.1021-1028.1966
更新日期:1966-03-01 00:00:00
abstract::Strains carrying either the polA1 or resA1 mutation are deficient in DNA polymerase I, and the polA1 and resA1 mutations do not complement in merozygotes. The effect of these mutations in otherwise identical genetic backgrounds was studied: after ultraviolet irradiation both strains degrade their DNA more rapidly and ...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.114.3.951-955.1973
更新日期:1973-06-01 00:00:00
abstract::OxyR is a DNA binding protein that differentially regulates a cell's response to hydrogen peroxide-mediated oxidative stress. We previously reported that the reduced form of OxyR is sufficient for repression of transcription of agn43 from unmethylated template DNA, which is essential for deoxyadenosine methylase (Dam)...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.185.7.2203-2209.2003
更新日期:2003-04-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.6.2748-2754.1987
更新日期:1987-06-01 00:00:00
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journal_title:Journal of bacteriology
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更新日期:1968-01-01 00:00:00
abstract::The so-called symbiotic region of the Bradyrhizobium japonicum chromosome (C. Kündig, H. Hennecke, and M. Göttfert, J. Bacteriol. 175:613-622, 1993) was screened for the presence of genes controlled by the nitrogen fixation regulatory protein NifA. Southern blots of restriction enzyme-digested cosmids that represent a...
journal_title:Journal of bacteriology
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更新日期:2000-03-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.180.17.4667-4675.1998
更新日期:1998-09-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.02274-14
更新日期:2015-01-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.3.1349-1351.1987
更新日期:1987-03-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.175.6.1723-1734.1993
更新日期:1993-03-01 00:00:00
abstract::Tn4551, a clindamycin resistance (Ccr) transposon from the R plasmid pBI136, was cloned onto an Escherichia coli-Bacteroides shuttle vector which could replicate normally in E. coli but was maintained unstably in Bacteroides fragilis. To aid in cloning and to ensure maintenance of Tn4551 in E. coli, a kanamycin resist...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.169.8.3450-3457.1987
更新日期:1987-08-01 00:00:00
abstract::A Boivin preparation of Brucella abortus, unlike common enterobacterial endotoxins, failed to depress water intake or increase numbers of hemolysin-producing spleen cells in mice, or to cause delayed inflammatory reactions in rabbit skin. Reactivity to the B. abortus endotoxin was found only in animals which were prev...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.95.2.286-290.1968
更新日期:1968-02-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.151.1.462-464.1982
更新日期:1982-07-01 00:00:00
abstract::Two solid medium formulations, designated 100:10 and 10:10, were developed for the growth of Thiobacillus ferrooxidans. The new media contain a mixture of both ferrous iron and thiosulfate as available energy sources, permitting the detection of colony morphology variants that arise spontaneously in a wild-type popula...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/jb.170.9.3915-3923.1988
更新日期:1988-09-01 00:00:00
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journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.158.1.23-28.1984
更新日期:1984-04-01 00:00:00
abstract::The colicinogenic B factor, transferred from Escherichia coli strain K77 (and termed ColB2-K77 or ColB2) to an E. coli K12 F(-) strain, is capable of promoting its own transfer to other K12 F(-) strains at a low rate (from LFC cultures) which can be increased under special conditions (HFC cultures). LFC cultures of K1...
journal_title:Journal of bacteriology
pub_type: 杂志文章
doi:10.1128/JB.107.3.900-906.1971
更新日期:1971-09-01 00:00:00