Requirements for suppression of a dnaG mutation by an I-type plasmid.
C Sasakawa,M Yoshikawa +1 more
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TLDR
The authentic derepressed mutation of the conjugal fertility system was shown to be one of the requirements and a previously undescribed type of mutation leading to a far higher degree of derepression of this system than the authentic drd mutation was shown.Abstract:
We have confirmed and further characterized the phenomenon of suppression of a dnaG mutation by an I plasmid and determined the requirements for the complete expression of suppressibility. The authentic derepressed mutation of the conjugal fertility system, described earlier, was shown to be one of the requirements. The second requirement is a previously undescribed type of mutation leading to a far higher degree of derepression of this system than the authentic drd mutation. This second mutation leads to extremely high conjugal fertility and pilus production. A third requirement for the complete expression of suppressibility is that the host recA function remain intact. recA function is required not merely for the fulfillment of the other two requirements described above, but also for an additional step or steps leading to its complete expression. The nature of this step(s) is unknown, but it is not insertion of the plasmid into the host genome.read more
Citations
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Journal ArticleDOI
Processing of plasmid DNA during bacterial conjugation.
Neil Willetts,B Wilkins +1 more
TL;DR: Coupure et initiation du transfert d'ADN au site d'origine de transfert, separation des 2 brins d ADN plasmidiques, transfert des brins, synthese d’ADN dans les cellules donneuses and receptrices and recircularisation des molecules de plasmides repliquees.
Journal ArticleDOI
Plasmid RP4 specifies a deoxyribonucleic acid primase involved in its conjugal transfer and maintenance.
TL;DR: The RP4-specified primase seems to serve two functions: the single DNA strand transferred during conjugation is primed by it in the recipient cell, and it appears to be necessary for the efficient priming of discontinuous plasmid DNA replication despite the presence of the chromosomal priming system.
Book ChapterDOI
Conjugative Pili and Pilus-Specific Phages
TL;DR: In the early 1960s, a number of bacteriophages specific for “male” strains of Escherichia coli were discovered both at the Rockefeller University and in Germany.
Journal ArticleDOI
A plasmid DNA primase active in discontinuous bacterial DNA replication
TL;DR: A DNA primase encoded by an IncIα plasmid promotes efficient DNA replication in a primase-defective mutant of Escherichia coli, implying that the plasmids enzyme can prime discontinuous DNA synthesis of the bacterial chromosome.
References
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TL;DR: This article corrects the article on p. 116 in vol.
Journal ArticleDOI
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