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Book Regulation of Chromosomal DNA Replication in Escherichia Coli

Download or read book Regulation of Chromosomal DNA Replication in Escherichia Coli written by Lyle Adair Simmons and published by . This book was released on 2003 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Regulation of Gene Expression in Escherichia coli

Download or read book Regulation of Gene Expression in Escherichia coli written by E. C. C. Lin and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 1010 pages. Available in PDF, EPUB and Kindle. Book excerpt: This up-to-date guide focuses on the understanding of key regulatory mechanisms governing gene expression in Escherichia coli. Studies of E. coli not only provide the first models of gene regulation, but research continues to yield different control mechanisms.

Book Growth Rate Regulation and Control of Initiation of DNA Replication in Escherichia Coli

Download or read book Growth Rate Regulation and Control of Initiation of DNA Replication in Escherichia Coli written by Anne Eliane Chiaramello and published by . This book was released on 1990 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: The initiation of DNA synthesis at the chromosomal replication origin, oriC, in Escherichia coli involves an RNA polymerase-mediated step. The level of synthesis of transcripts moving counterclockwise toward oriC is controlled at two promoters, P1 (asnC) and P2 (mioC), and at two transcription terminator regions, T1 and T2. As shown by S1 mapping, termination at the T2 region occurs to the right of oriC at nucleotides 297-299 and 306-310, while major termination events in the T1 region occur in and near the mioC promoter. The majority of transcripts entering oriC originates from the mioC promoter. Transcription from the mioC promoter has been shown to enhance the frequency of initiation of DNA replication of oriC containing plasmids, and to stabilize these plasmids in the host cells. The mioC promoter, which is stringently controlled, is also growth rate regulated. The amount of mioC transcripts relative to the amount of total RNA was inversely correlated with growth rate. This transcript is characterized by a short half-life (1.5 min). The mioC promoter, which contains a DnaA protein binding site, was much less susceptible to repression by DnaA protein when located in the chromosome, than when located in a plasmid. Only a very high concentration of DnaA protein repressed the mioC promoter. The DnaA protein, which is required for initiation of DNA replication from oriC, is growth rate regulated. As shown by RNase protection, this regulation is exerted at the transcriptional level, affecting both promoters, dnaAp1 and dnaAp2. Transcription from these two promoters is also stringently controlled. The amount of DnaA protein in spoT mutants, which are deficient in ppGpp pyrophosphorylase activity, decreases as the severity in the mutation increases. Thus, the intracellular concentration of ppGpp influences the expression of the dnaA gene. In conclusion, the growth rate regulation and stringent control of the dnaA gene suggest that one way in which DNA replication is coordinated with the growth rate is via ppGpp synthesis at the ribosome.

Book Regulation of the DnaA Promoter in Escherichia Coli

Download or read book Regulation of the DnaA Promoter in Escherichia Coli written by Victoria Goehner Newman and published by . This book was released on 1999 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt: The timing of initiation of DNA replication from oriC in E. coli is regulated by the concentration of the DnaA protein. Increases in the intracellular DnaA protein concentration over 1.5 fold normal levels causes asynchronous timing of initiation of DNA replication. The regulators of the dnaA operon must keep the DnaA concentration within tight limits yet be able to respond to rapidly changing environmental conditions. Here it is shown that Fis and DnaA proteins interact, in conjunction with other factors, to regulate the expression of dnaA. Binding of DnaA to the DnaA box in the dnaA promoter region is destabilized by the binding of Fis to its binding site in dnaAp2. However, DnaA94, containing only the C-terminal 94 amino acids of the DnaA protein and retaining specific binding activity to the DnaA box of the dnaA promoter region, is not destabilized by Fis binding. DNase I and copper-phenanthroline (Cu-op) footprinting studies of DnaA and DnaA94 support the existence of a second weak DnaA box which abuts the DNase I and Cu-op footprints of Fis in the dnaAp2 promoter. We determined that the GC-rich region of the dnaAp2 promoter is analogous to the discriminator sequence (DS) of rRNA promoters, in that the GC-rich sequence mediates the repression caused by elevated levels of guanosine tetraphosphate (ppGpp). During starvation conditions, the alarmone ppGpp is synthesized. Overexpression of ppGpp causes inhibition of dnaAp2 promoter transcription, which is alleviated when the GC-rich DS is mutated to an AT-rich sequence. We conclude that this site is responsible for mediating the stringent control of the dnaAp2 promoter. Incorrect timing of initiation in the cell cycle results in asynchronous replication. Strains with a mutated DS, DnaA box, or Fis binding site in the dnaA promoter region on the chromosome have increased levels of dnaA gene expression. These mutants initiate DNA replication synchronously in minimal M9 medium as shown by flow cytometric assays. In rich medium, the DS, mutant showed very limited asynchrony, whereas the other mutants replicated synchronously.

Book Gene Function

    Book Details:
  • Author : Robert E. Glass
  • Publisher : Univ of California Press
  • Release : 1982-01-01
  • ISBN : 9780520046542
  • Pages : 516 pages

Download or read book Gene Function written by Robert E. Glass and published by Univ of California Press. This book was released on 1982-01-01 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Initiation of DNA Replication in Escherichia Coli K 12

Download or read book The Initiation of DNA Replication in Escherichia Coli K 12 written by Nancy Ann Schaus and published by . This book was released on 1980 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Regulation of Several Genes Involved in DNA Replication in Escherichia Coli

Download or read book Regulation of Several Genes Involved in DNA Replication in Escherichia Coli written by Thomas David Daws and published by . This book was released on 1988 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Structure and Regulation of the DnaA Gene of Escherichia Coli K12

Download or read book Structure and Regulation of the DnaA Gene of Escherichia Coli K12 written by E. Bech Hansen and published by . This book was released on 1984 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Role of the DnaA Function in the Regulation of DNA Replication in Escherichia Coli

Download or read book The Role of the DnaA Function in the Regulation of DNA Replication in Escherichia Coli written by Joachim Frey and published by . This book was released on 1980 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Molecular Life Sciences

    Book Details:
  • Author : Robert D. Wells
  • Publisher : Springer
  • Release : 2018-01-12
  • ISBN : 9781461415299
  • Pages : 0 pages

Download or read book Molecular Life Sciences written by Robert D. Wells and published by Springer. This book was released on 2018-01-12 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Molecular Life Sciences: An Encyclopedic Reference will focus on understanding biological phenomena at the level of molecules and their interactions that govern life processes. The work will include articles on genes and genomes, protein structure and function, systems biology using genomics and proteomics as the focus, molecular aspects of cell structure and function, unifying concepts and theories from biology, chemistry, mathematics and physics that are essential for understanding the molecular life sciences (including teaching perspectives and assessment tools), and basic aspects of the various experimental approaches that are used in the Molecular Life Sciences.

Book Growth Rate Regulation and Control of Initiation of DNA Replication in E  s  c  h  e  r  i  c  h  i  a   C  o  l  i

Download or read book Growth Rate Regulation and Control of Initiation of DNA Replication in E s c h e r i c h i a C o l i written by and published by . This book was released on 1990 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: The initiation of DNA synthesis at the chromosomal replication origin, oriC, in Escherichia coli involves an RNA polymerase-mediated step. The level of synthesis of transcripts moving counterclockwise toward oriC is controlled at two promoters, P1 (asnC) and P2 (mioC), and at two transcription terminator regions, T1 and T2. As shown by S1 mapping, termination at the T2 region occurs to the right of oriC at nucleotides 297-299 and 306-310, while major termination events in the T1 region occur in and near the mioC promoter. The majority of transcripts entering oriC originates from the mioC promoter. Transcription from the mioC promoter has been shown to enhance the frequency of initiation of DNA replication of oriC containing plasmids, and to stabilize these plasmids in the host cells. The mioC promoter, which is stringently controlled, is also growth rate regulated. The amount of mioC transcripts relative to the amount of total RNA was inversely correlated with growth rate. This transcript is characterized by a short half-life (1.5 min). The mioC promoter, which contains a DnaA protein binding site, was much less susceptible to repression by DnaA protein when located in the chromosome, than when located in a plasmid. Only a very high concentration of DnaA protein repressed the mioC promoter. The DnaA protein, which is required for initiation of DNA replication from oriC, is growth rate regulated. As shown by RNase protection, this regulation is exerted at the transcriptional level, affecting both promoters, dnaAp1 and dnaAp2. Transcription from these two promoters is also stringently controlled. The amount of DnaA protein in spoT mutants, which are deficient in ppGpp pyrophosphorylase activity, decreases as the severity in the mutation increases. Thus, the intracellular concentration of ppGpp influences the expression of the dnaA gene. In conclusion, the growth rate regulation and stringent control of the dnaA gene suggest that one way in which DNA replication is coordinated with the growth rate is via ppGpp synthesis at the ribosome.

Book Molecular Biology of the Gene

    Book Details:
  • Author : James D. Watson
  • Publisher : Benjamin-Cummings Publishing Company
  • Release : 2014
  • ISBN : 9780321762436
  • Pages : 872 pages

Download or read book Molecular Biology of the Gene written by James D. Watson and published by Benjamin-Cummings Publishing Company. This book was released on 2014 with total page 872 pages. Available in PDF, EPUB and Kindle. Book excerpt: Now completely up-to-date with the latest research advances, the Seventh Edition retains the distinctive character of earlier editions. Twenty-two concise chapters, co-authored by six highly distinguished biologists, provide current, authoritative coverage of an exciting, fast-changing discipline.

Book Recombinational Repair of DNA Damage

Download or read book Recombinational Repair of DNA Damage written by Andrei Kuzminov and published by Landes Bioscience. This book was released on 1996 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Cumulated Index Medicus

Download or read book Cumulated Index Medicus written by and published by . This book was released on 1994 with total page 1364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book DNA Replication Control in Microbial Cell Factories

Download or read book DNA Replication Control in Microbial Cell Factories written by Monika Glinkowska and published by Springer. This book was released on 2014-09-23 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work describes the current knowledge of biochemical mechanisms regulating initiation of DNA replication in Escherichia coli, which focuses on the control of activity of the DnaA protein. Examples of direct linkages between DNA replication and other cellular processes are provided. In addition, similarities of the mechanisms of regulation of DNA replication operating in prokaryotic and eukaryotic cells are identified, and implications for understanding more complex processes, like carcinogenesis are suggested. Studies of recent years provided evidence that regulation of DNA replication in bacteria is more complex than previously anticipated. Multiple layers of control seem to ensure coordination of this process with the increase of cellular mass and the division cycle. Metabolic processes and membrane composition may serve as points where integration of genome replication with growth conditions occurs. It is also likely that coupling of DNA synthesis with cellular metabolism may involve interactions of replication proteins with other macromolecular complexes, responsible for various cellular processes. Thus, the exact set of factors participating in triggering the replication initiation may differ depending on growth conditions. Therefore, understanding the regulation of DNA duplication requires placing this process in the context of the current knowledge on bacterial metabolism, as well as cellular and chromosomal structure. Moreover, in both Escherichia coli and eukaryotic cells, replication initiator proteins were shown to play other roles in addition to driving the assembly of replication complexes, which constitutes another, yet not sufficiently understood, layer of coordinating DNA replication with the cell cycle.