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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 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 The role of the DNA function in the regulation of DNA replication in  Escherichia coli

Download or read book The role of the DNA 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 DNA Replication  The Regulatory Mechanisms

Download or read book DNA Replication The Regulatory Mechanisms written by Patrick Hughes and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 429 pages. Available in PDF, EPUB and Kindle. Book excerpt: DNA replication is a key event in the cell cycle. Although our knowledge is far from complete and many elusive regulatory mechanisms still remain beyondour grasp, many enzymes and a multiplicity of biochemical mechanisms involved have been discovered. Recent findings in E. coli have confirmed and yet surpassed the original hypothesis of F. Jacob. In yeast and higher eucaryotes, the apparent redundancy in putative origins and initiators has made an estimation of the importance of each identified element difficult to access. In spite of well established methodologies - which are also described in the book - the origin identification in mammalian chromosomes is still a controversial subject. On the other hand, considerable advances have been made in our understanding of virus DNA replication and this continues to deepen and broaden our understanding of the controls of cellular DNA replication.

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 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.

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 DNA Replication

    Book Details:
  • Author : Hisao Masai
  • Publisher : Springer
  • Release : 2018-01-22
  • ISBN : 9811069557
  • Pages : 581 pages

Download or read book DNA Replication written by Hisao Masai and published by Springer. This book was released on 2018-01-22 with total page 581 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the latest trends and future directions of DNA replication research. The contents reflect upon the principles that have been established through the genetic and enzymatic studies of bacterial, viral, and cellular replication during the past decades. The book begins with a historical overview of the studies on eukaryotic DNA replication by Professor Thomas Kelly, a pioneer of the field. The following chapters include genome-wide studies of replication origins and initiation factor binding, as well as the timing of DNA replications, mechanisms of initiation, DNA chain elongation and termination of DNA replication, the structural basis of functions of protein complexes responsible for execution of DNA replication, cell cycle-dependent regulation of DNA replication, the nature of replication stress and cells’ strategy to deal with the stress, and finally how all these phenomena are interconnected to genome instability and development of various diseases. By reviewing the existing concepts ranging from the old principles to the newest ideas, the book gives readers an opportunity to learn how the classical replication principles are now being modified and new concepts are being generated to explain how genome DNA replication is achieved with such high adaptability and plasticity. With the development of new methods including cryoelectron microscopy analyses of huge protein complexes, single molecular analyses of initiation and elongation of DNA replication, and total reconstitution of eukaryotic DNA replication with purified factors, the field is enjoying one of its most exciting moments, and this highly timely book conveys that excitement to all interested readers.

Book Mechanism and Regulation of DNA Replication

Download or read book Mechanism and Regulation of DNA Replication written by Alan Kolber and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 457 pages. Available in PDF, EPUB and Kindle. Book excerpt: 1 - Chromosome Replication in Procaryotes.- Enzymatic Aspects of Chromosome Replication in E. coli.- Escherichia coli DNA Polymerase II and III.- Initiation of DNA Synthesis.- In vitro Replication of DNA.- The Role of ATP in Chromosome Replication Studied in Toluenized Escherichia coli.- Membrane Protein Components and DNA Synthesis in Escherichia coli.- A Possible Common Role for DNA Polymerase I and Exonuclease V in Escherichia coli.- The Joining of DNA Duplexes at Their Base-Paired Ends.- The Attachment of the Bacterial Chromosome to the Cell Membrane.- DNA Replication in Bacteriophage and.

Book DNA Replication Origins in Microbial Genomes

Download or read book DNA Replication Origins in Microbial Genomes written by Feng Gao and published by Frontiers Media SA. This book was released on 2016-03-11 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: DNA replication, a central event for cell proliferation, is the basis of biological inheritance. Complete and accurate DNA replication is integral to the maintenance of the genetic integrity of organisms. In all three domains of life, DNA replication begins at replication origins. In bacteria, replication typically initiates from a single replication origin (oriC), which contains several DnaA boxes and the AT-rich DNA unwinding element (DUE). In eukaryotic genomes, replication initiates from significantly more replication origins, activated simultaneously at a specific time. For eukaryotic organisms, replication origins are best characterized in the unicellular eukaryote budding yeast Saccharomyces cerevisiae and the fission yeast Schizosaccharomyces pombe. The budding yeast origins contain an essential sequence element called the ARS (autonomously replicating sequence), while the fission yeast origins consist of AT-rich sequences. Within the archaeal domain, the multiple replication origins have been identified by a predict-and-verify approach in the hyperthermophilic archaeon Sulfolobus. The basic structure of replication origins is conserved among archaea, typically including an AT-rich unwinding region flanked by several short repetitive DNA sequences, known as origin recognition boxes (ORBs). It appears that archaea have a simplified version of the eukaryotic replication apparatus, which has led to considerable interest in the archaeal machinery as a model of that in eukaryotes. The research on replication origins is important not only in providing insights into the structure and function of the replication origins but also in understanding the regulatory mechanisms of the initiation step in DNA replication. Therefore, intensive studies have been carried out in the last two decades. The pioneer work to identify bacterial oriCs in silico is the GC-skew analysis. Later, a method of cumulative GC skew without sliding windows was proposed to give better resolution. Meanwhile, an oligomer-skew method was also proposed to predict oriC regions in bacterial genomes. As a unique representation of a DNA sequence, the Z-curve method has been proved to be an accurate and effective approach to predict bacterial and archaeal replication origins. Budding yeast origins have been predicted by Oriscan using similarity to the characterized ones, while the fission yeast origins have been identified initially from AT content calculation. In comparison with the in silico analysis, the experimental methods are time-consuming and labor-intensive, but convincing and reliable. To identify microbial replication origins in vivo or in vitro, a number of experimental methods have been used including construction of replicative oriC plasmids, microarray-based or high-throughput sequencing-based marker frequency analysis, two-dimensional gel electrophoresis analysis and replication initiation point mapping (RIP mapping). The recent genome-wide approaches to identify and characterize replication origin locations have boosted the number of mapped yeast replication origins. In addition, the availability of increasing complete microbial genomes and emerging approaches has created challenges and opportunities for identification of their replication origins in silico, as well as in vivo and in vitro. The Frontiers in Microbiology Research Topic on DNA replication origins in microbial genomes is devoted to address the issues mentioned above, and aims to provide a comprehensive overview of current research in this field.

Book DNA Replication Controls  Volume 1

Download or read book DNA Replication Controls Volume 1 written by Eishi Noguchi and published by MDPI. This book was released on 2018-04-27 with total page 313 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "DNA Replication Controls" that was published in Genes

Book Molecular Biology of the Cell

Download or read book Molecular Biology of the Cell written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: