dnaB

Summary

Gene Symbol: dnaB
Description: replicative DNA helicase
Alias: ECK4044, JW4012, groP, grpA, grpD
Species: Escherichia coli str. K-12 substr. MG1655

Top Publications

  1. Mitkova A, Khopde S, Biswas S. Mechanism and stoichiometry of interaction of DnaG primase with DnaB helicase of Escherichia coli in RNA primer synthesis. J Biol Chem. 2003;278:52253-61 pubmed
    ..synthesis of RNA primers in the lagging strand of the replication fork in Escherichia coli requires the replicative DnaB helicase and the DNA primase, the DnaG gene product...
  2. Donate L, Llorca O, Barcena M, Brown S, Dixon N, Carazo J. pH-controlled quaternary states of hexameric DnaB helicase. J Mol Biol. 2000;303:383-93 pubmed
    b>DnaB is the major helicase in the Escherichia coli replisome. It is a homohexameric enzyme that interacts with many other replisomal proteins and cofactors...
  3. Biswas S, Chen P, Biswas E. Structure and function of Escherichia coli DnaB protein: role of the N-terminal domain in helicase activity. Biochemistry. 1994;33:11307-14 pubmed
    We have analyzed the contributions of specific domains of DnaB helicase to its quaternary structure and multienzyme activities. Highly purified tryptic fragments containing various domains of DnaB helicase were prepared...
  4. Lu Y, Ratnakar P, Mohanty B, Bastia D. Direct physical interaction between DnaG primase and DnaB helicase of Escherichia coli is necessary for optimal synthesis of primer RNA. Proc Natl Acad Sci U S A. 1996;93:12902-7 pubmed
    The primase DnaG of Escherichia coli requires the participation of the replicative helicase DnaB for optimal synthesis of primer RNA for lagging strand replication...
  5. Harris D, Pollock S, Wood E, Goiffon R, Klingele A, Cabot E, et al. Directed evolution of ionizing radiation resistance in Escherichia coli. J Bacteriol. 2009;191:5240-52 pubmed publisher
    ..At least some evolutionary pathways to extreme radiation resistance are constrained by the temporally ordered appearance of specific alleles. ..
  6. Wahle E, Lasken R, Kornberg A. The dnaB-dnaC replication protein complex of Escherichia coli. I. Formation and properties. J Biol Chem. 1989;264:2463-8 pubmed
    The complex formed between the dnaB and dnaC replication proteins of Escherichia coli is stabilized by ATP binding to dnaC. The dnaB6-dnaC6-ATP6 complex can be maintained without ATP hydrolysis at a concentration as low as 5 x 10(-10) M...
  7. Lebowitz J, McMacken R. The Escherichia coli dnaB replication protein is a DNA helicase. J Biol Chem. 1986;261:4738-48 pubmed
    Genetic and biochemical analyses indicate that the Escherichia coli dnaB replication protein functions in the propagation of replication forks in the bacterial chromosome...
  8. Soni R, Mehra P, Mukhopadhyay G, Dhar S. Helicobacter pylori DnaB helicase can bypass Escherichia coli DnaC function in vivo. Biochem J. 2005;389:541-8 pubmed publisher
    In Escherichia coli, DnaC is essential for loading DnaB helicase at oriC (the origin of chromosomal DNA replication)...
  9. Wickner S, Hurwitz J. Interaction of Escherichia coli dnaB and dnaC(D) gene products in vitro. Proc Natl Acad Sci U S A. 1975;72:921-5 pubmed
    Purified E. coli dnaB and dnaC(D) gene products interact physically and functionally in vitro...
  10. Yancey Wrona J, Matson S. Bound Lac repressor protein differentially inhibits the unwinding reactions catalyzed by DNA helicases. Nucleic Acids Res. 1992;20:6713-21 pubmed
    ..The helicase reactions catalyzed by E. coli DnaB protein and helicase IV were substantially inhibited by the presence of bound protein...

Detail Information

Publications97

  1. Mitkova A, Khopde S, Biswas S. Mechanism and stoichiometry of interaction of DnaG primase with DnaB helicase of Escherichia coli in RNA primer synthesis. J Biol Chem. 2003;278:52253-61 pubmed
    ..synthesis of RNA primers in the lagging strand of the replication fork in Escherichia coli requires the replicative DnaB helicase and the DNA primase, the DnaG gene product...
  2. Donate L, Llorca O, Barcena M, Brown S, Dixon N, Carazo J. pH-controlled quaternary states of hexameric DnaB helicase. J Mol Biol. 2000;303:383-93 pubmed
    b>DnaB is the major helicase in the Escherichia coli replisome. It is a homohexameric enzyme that interacts with many other replisomal proteins and cofactors...
  3. Biswas S, Chen P, Biswas E. Structure and function of Escherichia coli DnaB protein: role of the N-terminal domain in helicase activity. Biochemistry. 1994;33:11307-14 pubmed
    We have analyzed the contributions of specific domains of DnaB helicase to its quaternary structure and multienzyme activities. Highly purified tryptic fragments containing various domains of DnaB helicase were prepared...
  4. Lu Y, Ratnakar P, Mohanty B, Bastia D. Direct physical interaction between DnaG primase and DnaB helicase of Escherichia coli is necessary for optimal synthesis of primer RNA. Proc Natl Acad Sci U S A. 1996;93:12902-7 pubmed
    The primase DnaG of Escherichia coli requires the participation of the replicative helicase DnaB for optimal synthesis of primer RNA for lagging strand replication...
  5. Harris D, Pollock S, Wood E, Goiffon R, Klingele A, Cabot E, et al. Directed evolution of ionizing radiation resistance in Escherichia coli. J Bacteriol. 2009;191:5240-52 pubmed publisher
    ..At least some evolutionary pathways to extreme radiation resistance are constrained by the temporally ordered appearance of specific alleles. ..
  6. Wahle E, Lasken R, Kornberg A. The dnaB-dnaC replication protein complex of Escherichia coli. I. Formation and properties. J Biol Chem. 1989;264:2463-8 pubmed
    The complex formed between the dnaB and dnaC replication proteins of Escherichia coli is stabilized by ATP binding to dnaC. The dnaB6-dnaC6-ATP6 complex can be maintained without ATP hydrolysis at a concentration as low as 5 x 10(-10) M...
  7. Lebowitz J, McMacken R. The Escherichia coli dnaB replication protein is a DNA helicase. J Biol Chem. 1986;261:4738-48 pubmed
    Genetic and biochemical analyses indicate that the Escherichia coli dnaB replication protein functions in the propagation of replication forks in the bacterial chromosome...
  8. Soni R, Mehra P, Mukhopadhyay G, Dhar S. Helicobacter pylori DnaB helicase can bypass Escherichia coli DnaC function in vivo. Biochem J. 2005;389:541-8 pubmed publisher
    In Escherichia coli, DnaC is essential for loading DnaB helicase at oriC (the origin of chromosomal DNA replication)...
  9. Wickner S, Hurwitz J. Interaction of Escherichia coli dnaB and dnaC(D) gene products in vitro. Proc Natl Acad Sci U S A. 1975;72:921-5 pubmed
    Purified E. coli dnaB and dnaC(D) gene products interact physically and functionally in vitro...
  10. Yancey Wrona J, Matson S. Bound Lac repressor protein differentially inhibits the unwinding reactions catalyzed by DNA helicases. Nucleic Acids Res. 1992;20:6713-21 pubmed
    ..The helicase reactions catalyzed by E. coli DnaB protein and helicase IV were substantially inhibited by the presence of bound protein...
  11. Biswas E, Biswas S. Mechanism of DnaB helicase of Escherichia coli: structural domains involved in ATP hydrolysis, DNA binding, and oligomerization. Biochemistry. 1999;38:10919-28 pubmed
    We describe the delineation of three distinct structural domains of the DnaB helicase of Escherichia coli: domain alpha, amino acid residues (aa) 1-156; domain beta, aa 157-302; and domain gamma, aa 303-471...
  12. Ng J, Marians K. The ordered assembly of the phiX174-type primosome. II. Preservation of primosome composition from assembly through replication. J Biol Chem. 1996;271:15649-55 pubmed
    ..formed on single-stranded DNA-binding protein-coated phiX174 DNA by the combination of PriA, PriB, PriC, DnaT, DnaB, DnaC, and DnaG...
  13. Michel B, Ehrlich S, Uzest M. DNA double-strand breaks caused by replication arrest. EMBO J. 1997;16:430-8 pubmed
    ..Two E. coli replicative helicases were tested, Rep, which is essential in recBC mutants, and DnaB. The proportion of linear DNA increased up to 50% upon shift of rep recBTS recCTS cells to restrictive temperature...
  14. Biswas E, Biswas S, Bishop J. The dnaB protein of Escherichia coli: mechanism of nucleotide binding, hydrolysis, and modulation by dnaC protein. Biochemistry. 1986;25:7368-74 pubmed
    The mechanism of nucleotide binding and hydrolysis by dnaB protein and dnaB X dnaC protein complex has been studied by using fluorescent nucleotide analogues...
  15. Kedzierska B, Glinkowska M, Iwanicki A, Obuchowski M, Sojka P, Thomas M, et al. Toxicity of the bacteriophage lambda cII gene product to Escherichia coli arises from inhibition of host cell DNA replication. Virology. 2003;313:622-8 pubmed
    ..coli dnaB and dnaC genes...
  16. Tougu K, Marians K. The interaction between helicase and primase sets the replication fork clock. J Biol Chem. 1996;271:21398-405 pubmed
    ..and that association of primase with the replication fork is via a protein-protein interaction with the helicase, DnaB. We describe here mutant primases that have an altered interaction with DnaB and that direct the synthesis of ..
  17. Funnell B, Baker T, Kornberg A. Complete enzymatic replication of plasmids containing the origin of the Escherichia coli chromosome. J Biol Chem. 1986;261:5616-24 pubmed
    ..the origin of the Escherichia coli chromosome, oriC, formation of an active initiation complex consisting of dnaA, dnaB, dnaC, and HU proteins, requires a supercoiled DNA template...
  18. Mulcair M, Schaeffer P, Oakley A, Cross H, Neylon C, Hill T, et al. A molecular mousetrap determines polarity of termination of DNA replication in E. coli. Cell. 2006;125:1309-19 pubmed
    ..the rates of dissociation of Tus from forked TerB oligonucleotides, such as would be produced by the replicative DnaB helicase at both the fork-blocking (nonpermissive) and permissive ends of the Ter site...
  19. Chang S, Ng D, Baird L, Georgopoulos C. Analysis of an Escherichia coli dnaB temperature-sensitive insertion mutation and its cold-sensitive extragenic suppressor. J Biol Chem. 1991;266:3654-60 pubmed
    ..phage, it was shown through complementation and protein analyses, that the ts121 mutation is located in the dnaB gene...
  20. Galletto R, Jezewska M, Bujalowski W. Unzipping mechanism of the double-stranded DNA unwinding by a hexameric helicase: the effect of the 3' arm and the stability of the dsDNA on the unwinding activity of the Escherichia coli DnaB helicase. J Mol Biol. 2004;343:101-14 pubmed
    ..double-stranded DNA (dsDNA) part, on the kinetics of the dsDNA unwinding by the Escherichia coli hexameric helicase DnaB protein has been examined under single turnover conditions using the rapid quench-flow technique...
  21. Kaplan D, O Donnell M. DnaB drives DNA branch migration and dislodges proteins while encircling two DNA strands. Mol Cell. 2002;10:647-57 pubmed
    b>DnaB is a ring-shaped, hexameric helicase that unwinds the E. coli DNA replication fork while encircling one DNA strand. This report demonstrates that DnaB can also encircle both DNA strands and then actively translocate along the duplex...
  22. Chan A, Nagel R. On the participation of RecB in the induction of mini-Tn10 precise excision in a dnaB thermosensitive mutant. Mutat Res. 2004;548:47-52 pubmed
    ..The role of this and other repair proteins in DNA replication of the dnaB mutant in relation to the excision of the transposon is analyzed.
  23. Ehrlich S, Bertazzoni U, Bernardi G. The specificity of Escherichia coli endonuclease I. Eur J Biochem. 1973;40:149-53 pubmed
  24. Bastia D, Zzaman S, Krings G, Saxena M, Peng X, Greenberg M. Replication termination mechanism as revealed by Tus-mediated polar arrest of a sliding helicase. Proc Natl Acad Sci U S A. 2008;105:12831-6 pubmed publisher
    ..arrest at sequence-specific replication termini (Ter) by antagonizing DNA unwinding by the replicative helicase DnaB. Here, we report that Tus is also a polar antitranslocase...
  25. Ozaki S, Katayama T. DnaA structure, function, and dynamics in the initiation at the chromosomal origin. Plasmid. 2009;62:71-82 pubmed publisher
    ..b>DnaB helicase is loaded onto the unwound single-stranded region within oriC via interaction with the DnaA multimers...
  26. Funnell B, Baker T, Kornberg A. In vitro assembly of a prepriming complex at the origin of the Escherichia coli chromosome. J Biol Chem. 1987;262:10327-34 pubmed
    ..of DNA replication of plasmids containing the origin of the Escherichia coli chromosome (oriC), the proteins dnaA, dnaB, and dnaC interact and assemble a complex at oriC...
  27. Jones J, Nakai H. Duplex opening by primosome protein PriA for replisome assembly on a recombination intermediate. J Mol Biol. 1999;289:503-16 pubmed
    PriA and other primosome assembly proteins of Escherichia coli recruit the major replicative helicase DnaB for replisome assembly during bacteriophage Mu transposition and replication...
  28. Saito M, Tsugawa A, Egawa K, Nakamura Y. Revised sequence of the nusA gene of Escherichia coli and identification of nusA11 (ts) and nusA1 mutations which cause changes in a hydrophobic amino acid cluster. Mol Gen Genet. 1986;205:380-2 pubmed
    ..In the course of these experiments, several mistakes in the published nusA nucleotide sequence were found. These errors are revised in this article. The molecular weight of NusA is accordingly revised to 54,430. ..
  29. Molt K, Sutera V, Moore K, Lovett S. A role for nonessential domain II of initiator protein, DnaA, in replication control. Genetics. 2009;183:39-49 pubmed publisher
    ..DnaA binds to multiple sequences at the origin of replication, oriC, unwinding the DNA and promoting the binding of DnaB helicase...
  30. Hiasa H, Marians K. Differential inhibition of the DNA translocation and DNA unwinding activities of DNA helicases by the Escherichia coli Tus protein. J Biol Chem. 1992;267:11379-85 pubmed
    ..we have used a strand displacement assay to investigate the effect of Tus on the DNA helicase activities of DnaB, PriA, UvrD (helicase II), and the phi X-type primosome...
  31. Carl P. Escherichia coli mutants with temperature-sensitive synthesis of DNA. Mol Gen Genet. 1970;109:107-22 pubmed
  32. Saito H, Uchida H. Initiation of the DNA replication of bacteriophage lambda in Escherichia coli K12. J Mol Biol. 1977;113:1-25 pubmed
  33. Flowers S, Biswas E, Biswas S. Conformational dynamics of DnaB helicase upon DNA and nucleotide binding: analysis by intrinsic tryptophan fluorescence quenching. Biochemistry. 2003;42:1910-21 pubmed
    b>DnaB helicase of E. coli unwinds duplex DNA in the replication fork using the energy of ATP hydrolysis...
  34. Johnson S, Bhattacharyya S, Griep M. DnaB helicase stimulates primer synthesis activity on short oligonucleotide templates. Biochemistry. 2000;39:736-44 pubmed
    b>DnaB helicase stimulated the second-order RNA primer synthesis activity of primase by over 5000-fold on DNA templates that were 23 nucleotides long...
  35. Jezewska M, Kim U, Bujalowski W. Binding of Escherichia coli primary replicative helicase DnaB protein to single-stranded DNA. Long-range allosteric conformational changes within the protein hexamer. Biochemistry. 1996;35:2129-45 pubmed
    Quantitative analyses of the interactions of the Escherichia coli primary replicative helicase DnaB protein with single-stranded DNA have been performed using the thermodynamically rigorous fluorescence titration technique...
  36. Ikeda H, Shiraishi K, Ogata Y. Illegitimate recombination mediated by double-strand break and end-joining in Escherichia coli. Adv Biophys. 2004;38:3-20 pubmed
    ..that RecQ plays a role in the suppression of RecEmediated illegitimate recombination, with the participation of DnaB, Fis, Exol, and H-NS...
  37. Heller R, Marians K. The disposition of nascent strands at stalled replication forks dictates the pathway of replisome loading during restart. Mol Cell. 2005;17:733-43 pubmed
    ..One system for origin of replication-independent loading of the DnaB replicative helicase and subsequent replisome reassembly requires the structure-specific recognition factor PriA ..
  38. Griep M, Blood S, Larson M, Koepsell S, Hinrichs S. Myricetin inhibits Escherichia coli DnaB helicase but not primase. Bioorg Med Chem. 2007;15:7203-8 pubmed
    Primase and DnaB helicase play central roles during DNA replication initiation and elongation...
  39. Lohman T. Escherichia coli DNA helicases: mechanisms of DNA unwinding. Mol Microbiol. 1992;6:5-14 pubmed
    ..coli Rep, RecBCD and phage T7 gene 4 helicases. ..
  40. Saveson C, Lovett S. Enhanced deletion formation by aberrant DNA replication in Escherichia coli. Genetics. 1997;146:457-70 pubmed
    ..Especially large increases were observed in strains mutant in dnaQ the epsilon editing subunit of Pol III, and dnaB, the replication fork helicase...
  41. Kleinsteuber S, Quinones A. Expression of the dnaB gene of Escherichia coli is inducible by replication-blocking DNA damage in a recA-independent manner. Mol Gen Genet. 1995;248:695-702 pubmed
    The replicative DNA helicase encoded by the dnaB gene is essential for chromosomal DNA replication in Escherichia coli...
  42. Abe Y, Jo T, Matsuda Y, Matsunaga C, Katayama T, Ueda T. Structure and function of DnaA N-terminal domains: specific sites and mechanisms in inter-DnaA interaction and in DnaB helicase loading on oriC. J Biol Chem. 2007;282:17816-27 pubmed
    ..The interaction of the DnaA N terminus with the DnaB helicase is crucial for the loading of DnaB onto the unwound region...
  43. Georgopoulos C. Bacterial mutants in which the gene N function of bacteriophage lambda is blocked have an altered RNA polymerase. Proc Natl Acad Sci U S A. 1971;68:2977-81 pubmed
    ..This suggests that the groN mutation produces a structural change in the bacterial RNA polymerase such that it can no longer interact properly with the phage N product. ..
  44. Dodson M, Echols H, Wickner S, Alfano C, Mensa Wilmot K, Gomes B, et al. Specialized nucleoprotein structures at the origin of replication of bacteriophage lambda: localized unwinding of duplex DNA by a six-protein reaction. Proc Natl Acad Sci U S A. 1986;83:7638-42 pubmed
    ..Second, lambda P and host DnaB proteins interact with the O-some to generate a larger complex that includes additional DNA from an A + T-rich ..
  45. Dombroski A, Platt T. Structure of rho factor: an RNA-binding domain and a separate region with strong similarity to proven ATP-binding domains. Proc Natl Acad Sci U S A. 1988;85:2538-42 pubmed
    ..The implications of discrete domains for RNA and nucleotide binding are discussed in the context of requirements for specific interactions between RNA-binding and ATP-hydrolysis sites during transcription termination. ..
  46. Biswas S, Biswas Fiss E. Quantitative analysis of binding of single-stranded DNA by Escherichia coli DnaB helicase and the DnaB x DnaC complex. Biochemistry. 2006;45:11505-13 pubmed
    b>DnaB helicase is responsible for unwinding duplex DNA during chromosomal DNA replication and is an essential component of the DNA replication apparatus in Escherichia coli...
  47. Carr K, Kaguni J. Escherichia coli DnaA protein loads a single DnaB helicase at a DnaA box hairpin. J Biol Chem. 2002;277:39815-22 pubmed
    ..replication fork movement from the Escherichia coli replication origin (oriC) is the replicative helicase, DnaB. At oriC, two and only two helicase molecules are loaded, one for each replication fork...
  48. Bujalowski W, Jezewska M. Kinetic mechanism of nucleotide cofactor binding to Escherichia coli replicative helicase DnaB protein. stopped-flow kinetic studies using fluorescent, ribose-, and base-modified nucleotide analogues. Biochemistry. 2000;39:2106-22 pubmed
    The kinetic mechanism of binding nucleotide cofactors to the Escherichia coli primary replicative helicase DnaB protein has been studied, using the fluorescence stopped-flow technique...
  49. Sutton M, Carr K, Vicente M, Kaguni J. Escherichia coli DnaA protein. The N-terminal domain and loading of DnaB helicase at the E. coli chromosomal origin. J Biol Chem. 1998;273:34255-62 pubmed
    ..A step that follows is the binding of DnaB helicase at oriC so that it is properly positioned at each replication fork...
  50. San Martin C, Radermacher M, Wolpensinger B, Engel A, Miles C, Dixon N, et al. Three-dimensional reconstructions from cryoelectron microscopy images reveal an intimate complex between helicase DnaB and its loading partner DnaC. Structure. 1998;6:501-9 pubmed
    ..b>DnaB is the major replicative DNA helicase in Escherichia coli and has been used as a model system for studying the ..
  51. Bujalowski W, Klonowska M, Jezewska M. Oligomeric structure of Escherichia coli primary replicative helicase DnaB protein. J Biol Chem. 1994;269:31350-8 pubmed
    The oligomeric structure of the Escherichia coli primary replicative helicase DnaB protein in relation to the functions of the enzyme and the energetics of its stability has been characterized...
  52. Fang L, Davey M, O Donnell M. Replisome assembly at oriC, the replication origin of E. coli, reveals an explanation for initiation sites outside an origin. Mol Cell. 1999;4:541-53 pubmed
    ..coli origin, oriC. We show that two hexamers of DnaB assemble onto the opposing strands of the resulting bubble, expanding it further, yet helicase action is not ..
  53. Seitz H, Weigel C, Messer W. The interaction domains of the DnaA and DnaB replication proteins of Escherichia coli. Mol Microbiol. 2000;37:1270-9 pubmed
    The initiation of chromosome replication in Escherichia coli requires the recruitment of the replicative helicase DnaB from the DnaBC complex to the unwound region within the replication origin oriC, supported by the oriC-bound initiator ..
  54. Hiasa H, Marians K. Initiation of bidirectional replication at the chromosomal origin is directed by the interaction between helicase and primase. J Biol Chem. 1999;274:27244-8 pubmed
  55. Miller C, Cohen S. Separate roles of Escherichia coli replication proteins in synthesis and partitioning of pSC101 plasmid DNA. J Bacteriol. 1999;181:7552-7 pubmed
    ..replication proteins DnaA, which is required to initiate replication of both the chromosome and plasmid pSC101, and DnaB, the helicase that unwinds strands during DNA replication, have effects on plasmid partitioning that are distinct ..
  56. Paetz W, Nass G. Biochemical and immunological characterization of threonyl-tRNA synthetase of two borrelidin-resistant mutants of Escherichia coli K12. Eur J Biochem. 1973;35:331-7 pubmed
  57. Jezewska M, Rajendran S, Bujalowski W. Functional and structural heterogeneity of the DNA binding site of the Escherichia coli primary replicative helicase DnaB protein. J Biol Chem. 1998;273:9058-69 pubmed
    The structure-function relationship within the DNA binding site of the Escherichia coli replicative helicase DnaB protein was studied using nuclease digestion, quantitative fluorescence titration, centrifugation, and fluorescence energy ..
  58. Zhao X, Malik M, Chan N, Drlica Wagner A, Wang J, Li X, et al. Lethal action of quinolones against a temperature-sensitive dnaB replication mutant of Escherichia coli. Antimicrob Agents Chemother. 2006;50:362-4 pubmed
    Inhibition of DNA replication in an Escherichia coli dnaB-22 mutant failed to block quinolone-mediated lethality...
  59. Wyman C, Vasilikiotis C, Ang D, Georgopoulos C, Echols H. Function of the GrpE heat shock protein in bidirectional unwinding and replication from the origin of phage lambda. J Biol Chem. 1993;268:25192-6 pubmed
    ..specialized nucleoprotein structure that provides for the precise localization and activity of the Escherichia coli DnaB helicase at the lambda replication origin...
  60. Khachatourians G. Escherichia coli Hfr-DNA degradation in endonuclease I-deficient minicells. Biochim Biophys Acta. 1979;561:294-300 pubmed
    ..These experiments suggest that the presence of the endI- mutation in minicell-producing strain chi1268 leads to a greater loss in M2 of Hfr DNA conjugally transferred into the minicells. ..
  61. Arai K, Kornberg A. Mechanism of dnaB protein action. II. ATP hydrolysis by dnaB protein dependent on single- or double-stranded DNA. J Biol Chem. 1981;256:5253-9 pubmed
  62. Heller R, Marians K. Non-replicative helicases at the replication fork. DNA Repair (Amst). 2007;6:945-52 pubmed
    ..Restart systems operate to restore the 5'-->3' replicative helicase, DnaB, to the lagging-strand template...
  63. Chintakayala K, Larson M, Grainger W, Scott D, Griep M, Hinrichs S, et al. Domain swapping reveals that the C- and N-terminal domains of DnaG and DnaB, respectively, are functional homologues. Mol Microbiol. 2007;63:1629-39 pubmed
    The bacterial primase (DnaG)-helicase (DnaB) interaction is mediated by the C-terminal domain of DnaG (p16) and a linker that joins the N- and C-terminal domains (p17 and p33 respectively) of DnaB...
  64. Cherepanov P, Wackernagel W. Gene disruption in Escherichia coli: TcR and KmR cassettes with the option of Flp-catalyzed excision of the antibiotic-resistance determinant. Gene. 1995;158:9-14 pubmed
    ..This system was applied in the construction of an E. coli endA deletion mutation which can be transduced by P1 to the genetic background of interest using TcR as a marker. The transductant can then be freed of the TcR if required. ..
  65. Carr K, Kaguni J. Stoichiometry of DnaA and DnaB protein in initiation at the Escherichia coli chromosomal origin. J Biol Chem. 2001;276:44919-25 pubmed
    ..The prepriming complex then forms, involving the binding of DnaB helicase at oriC so that it is properly positioned at each replication fork...
  66. Yang S, Yu X, VanLoock M, Jezewska M, Bujalowski W, Egelman E. Flexibility of the rings: structural asymmetry in the DnaB hexameric helicase. J Mol Biol. 2002;321:839-49 pubmed
    b>DnaB is the primary replicative helicase in Escherichia coli and the hexameric DnaB ring has previously been shown to exist in two states in the presence of nucleotides...
  67. Seigneur M, Ehrlich S, Michel B. RuvABC-dependent double-strand breaks in dnaBts mutants require recA. Mol Microbiol. 2000;38:565-74 pubmed
    ..for the accessory replicative helicase Rep or deficient for the main Escherichia coli replicative helicase DnaB. We show that, in the rep mutant, RuvABC-mediated breakage occurs in the absence of the homologous recombination ..
  68. Yu X, Jezewska M, Bujalowski W, Egelman E. The hexameric E. coli DnaB helicase can exist in different Quaternary states. J Mol Biol. 1996;259:7-14 pubmed
    The DnaB protein is the primary replicative helicase in Escherichia coli, and the active form of the protein is a hexamer...
  69. Scherzinger E, Haring V, Lurz R, Otto S. Plasmid RSF1010 DNA replication in vitro promoted by purified RSF1010 RepA, RepB and RepC proteins. Nucleic Acids Res. 1991;19:1203-11 pubmed
    ..The bacterial RNA polymerase, the initiation protein DnaA, and the primosomal proteins DnaB, DnaC, DnaG and DnaT are not required...
  70. Kaboev O, Luchkina L. Template-free primer-independent DNA synthesis by bacterial DNA polymerases I using the DnaB protein from Escherichia coli. Dokl Biochem Biophys. 2004;398:265-7 pubmed
  71. Wechsler J, Nüsslein V, Otto B, Klein A, Bonhoeffer F, Herrmann R, et al. Isolation and characterization of thermosensitive Escherichia coli mutants defective in deoxyribonucleic acid replication. J Bacteriol. 1973;113:1381-8 pubmed
    ..This classification is congruent with that obtained by genetic mapping by using cotransduction frequencies with selected markers in P1 transduction analysis. ..
  72. Roychowdhury A, Szymanski M, Jezewska M, Bujalowski W. Escherichia coli DnaB helicase-DnaC protein complex: allosteric effects of the nucleotides on the nucleic acid binding and the kinetic mechanism of NTP hydrolysis. 3. Biochemistry. 2009;48:6747-63 pubmed publisher
    Allosteric interactions between the DNA- and NTP-binding sites of the Escherichia coli DnaB helicase engaged in the DnaB-DnaC complex and the mechanism of NTP hydrolysis by the complex have been examined using the fluorescence titration, ..
  73. Galletto R, Jezewska M, Bujalowski W. Interactions of the Escherichia coli DnaB helicase hexamer with the replication factor the DnaC protein. Effect of nucleotide cofactors and the ssDNA on protein-protein interactions and the topology of the complex. J Mol Biol. 2003;329:441-65 pubmed
    Quantitative studies of interactions between the Escherichia coli replication factor DnaC protein and the DnaB helicase have been performed using sedimentation velocity and fluorescence energy transfer techniques...
  74. Skokotas A, Wrobleski M, Hill T. Isolation and characterization of mutants of Tus, the replication arrest protein of Escherichia coli. J Biol Chem. 1994;269:20446-55 pubmed
    ..4100-fold lower affinity for Ter sites than wild type Tus and was unable to halt DNA replication in vivo or inhibit DnaB-catalyzed strand displacement in an in vitro helicase assay...
  75. Nakayama N, Arai N, Kaziro Y, Arai K. Structural and functional studies of the dnaB protein using limited proteolysis. Characterization of domains for DNA-dependent ATP hydrolysis and for protein association in the primosome. J Biol Chem. 1984;259:88-96 pubmed
    Two separable structural domains were identified in the Escherichia coli dnaB protein (Mr = 52,000) by partial proteolytic cleavage under nondenaturing conditions...
  76. Sclafani R, Wechsler J. High frequency of genetic duplications in the dnaB region of the Escherichia coli K12 chromosome. Genetics. 1981;98:677-89 pubmed
    The region that includes the dnaB locus on the E. coli K12 chromosome was shown to be duplicated at high frequency in cell populations. The duplications were shown to be arranged in tandem and segregated at various frequencies...
  77. Skarstad K, Wold S. The speed of the Escherichia coli fork in vivo depends on the DnaB:DnaC ratio. Mol Microbiol. 1995;17:825-31 pubmed
    The DnaC protein is required for loading the DnaB helicase at oriC. Thus DnaC promotes the formation of the pre-replication complex, but must leave the complex in order for the DnaB protein to function as a helicase...
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    The Escherichia coli DnaB protein (DnaB(6)) is the hexameric helicase that unwinds genomic DNA so it can be copied by the DNA replication machinery...
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    ..The digestion patterns were examined in relation to previous results of biochemical and crystallographic studies on dsDNA, and showed broad agreement. Endonuclease I cleaved ssDNA at sites corresponding to bent sites in dsDNA. ..
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    The modulation of enzymatic activities of Escherichia coli DnaB helicase by homologous and heterologous single-stranded DNA-binding proteins (SSBs) and its DNA substrates were analyzed...
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    ..When coupled to the replicative helicase DnaB, Pol III mediates leading-strand synthesis with a processivity of 10...
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    ..The mutation was found to cotransduce with malF3089:: Tn10 (at approximately 91.5 min) and a dnaB-expressing plasmid was able to complement fully the grpD55 defect in lambda replication...
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    ..An attractive structural model with direct biological significance for the function of this complex and also for the development of new antibacterial compounds is examined. ..
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    Kinetics of the double-stranded (ds) DNA unwinding by the Escherichia coli replicative helicase DnaB protein has been examined under single-turnover conditions using the chemical quench-flow technique...
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    ..of the high-affinity noninteracting nucleotide-binding site of Escherichia coli primary replicative helicase DnaB protein have been studied, using the base-modified fluorescent nucleotide analog 1, N6-ethenoadenosine diphosphate (..