| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
J. Biol. Chem., Vol. 263, Issue 7, 3208-3215, 03, 1988
EE Lahue and SW Matson
Helicase I has been purified to greater than 95% homogeneity from an F+
strain of Escherichia coli, and characterized as a single-stranded DNA-
dependent ATPase and a helicase. The duplex DNA unwinding reaction requires
a region of ssDNA for enzyme binding and concomitant nucleoside
5'-triphosphate hydrolysis. All eight predominant nucleoside
5'-triphosphates can satisfy this requirement. Unwinding is unidirectional
in the 5' to 3' direction. The length of duplex DNA unwound is independent
of protein concentration suggesting that the unwinding reaction is highly
processive. Kinetic analysis of the unwinding reaction indicates that the
enzyme turns over very slowly from one DNA substrate molecule to another.
The ATP hydrolysis reaction is continuous when circular partial duplex DNA
substrates are used as DNA effectors. When linear partial duplex substrates
are used ATP hydrolysis is barely detectable, although the kinetics of the
unwinding reaction on linear partial duplex substrates are identical to
those observed using a circular partial duplex DNA substrate. This suggests
that ATP hydrolysis fuels continuous translocation of helicase I on
circular single-stranded DNA while on linear single stranded DNA the enzyme
translocates to the end of the DNA molecule where it must slowly dissociate
from the substrate molecule and/or slowly associate with a new substrate
molecule, thus resulting in a very low rate of ATP hydrolysis.
Escherichia coli DNA helicase I catalyzes a unidirectional and highly processive unwinding reaction
Department of Biology, The University of North Carolina at Chapel Hill 27514.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  S. A. Lujan, L. M. Guogas, H. Ragonese, S. W. Matson, and M. R. Redinbo Disrupting antibiotic resistance propagation by inhibiting the conjugative DNA relaxase PNAS, July 24, 2007; 104(30): 12282 - 12287. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. L. Williams and J. F. Schildbach TraY and Integration Host Factor oriT Binding Sites and F Conjugal Transfer: Sequence Variations, but Not Altered Spacing, Are Tolerated J. Bacteriol., May 15, 2007; 189(10): 3813 - 3823. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Sikora, R. L. Eoff, S. W. Matson, and K. D. Raney DNA Unwinding by Escherichia coli DNA Helicase I (TraI) Provides Evidence for a Processive Monomeric Molecular Motor J. Biol. Chem., November 24, 2006; 281(47): 36110 - 36116. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. W. Matson and H. Ragonese The F-Plasmid TraI Protein Contains Three Functional Domains Required for Conjugative DNA Strand Transfer J. Bacteriol., January 15, 2005; 187(2): 697 - 706. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. C. Csitkovits, D. Thermic, and E. L. Zechner Concomitant Reconstitution of TraI-catalyzed DNA Transesterase and DNA Helicase Activity in Vitro J. Biol. Chem., October 29, 2004; 279(44): 45477 - 45484. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Choudhary, J. A. Sommers, and R. M. Brosh Jr. Biochemical and Kinetic Characterization of the DNA Helicase and Exonuclease Activities of Werner Syndrome Protein J. Biol. Chem., August 13, 2004; 279(33): 34603 - 34613. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. C. Csitkovits and E. L. Zechner Extent of Single-stranded DNA Required for Efficient TraI Helicase Activity in Vitro J. Biol. Chem., December 5, 2003; 278(49): 48696 - 48703. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. R. Byrd, J. K. Sampson, H. M. Ragonese, and S. W. Matson Structure-Function Analysis of Escherichia coli DNA Helicase I Reveals Non-overlapping Transesterase and Helicase Domains J. Biol. Chem., November 1, 2002; 277(45): 42645 - 42653. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Xu, G. Ziegelin, W. Schroder, J. Frank, S. Ayora, J. C. Alonso, E. Lanka, and W. Saenger Flavones inhibit the hexameric replicative helicase RepA Nucleic Acids Res., December 15, 2001; 29(24): 5058 - 5066. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Z. Ozsoy, J. J. Sekelsky, and S. W. Matson Biochemical characterization of the small isoform of Drosophila melanogaster RECQ5 helicase Nucleic Acids Res., July 15, 2001; 29(14): 2986 - 2993. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Ahnert and S. S. Patel Asymmetric Interactions of Hexameric Bacteriophage T7 DNA Helicase with the 5'- and 3'-Tails of the Forked DNA Substrate J. Biol. Chem., December 19, 1997; 272(51): 32267 - 32273. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. C. Nelson, M. T. Howard, J. A. Sherman, and S. W. Matson The traY Gene Product and Integration Host Factor Stimulate Escherichia coli DNA Helicase I-catalyzed Nicking at the F Plasmid oriT J. Biol. Chem., November 24, 1995; 270(47): 28374 - 28380. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. T. Howard, W. C. Nelson, and S. W. Matson Stepwise Assembly of a Relaxosome at the F Plasmid Origin of Transfer J. Biol. Chem., November 24, 1995; 270(47): 28381 - 28386. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. Fukuda and E. Ohtsubo Large Scale Purification and Characterization of TraI Endonuclease Encoded by Sex Factor Plasmid R100 J. Biol. Chem., September 8, 1995; 270(36): 21319 - 21325. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Dong and F. Dong The Phage T4-coded DNA Replication Helicase (gp41) Forms a Hexamer upon Activation by Nucleoside Triphosphate J. Biol. Chem., March 31, 1995; 270(13): 7462 - 7473. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. W. Matson, J. K. Sampson, and D. R. N. Byrd F Plasmid Conjugative DNA Transfer. THE TraI HELICASE ACTIVITY IS ESSENTIAL FOR DNA STRAND TRANSFER J. Biol. Chem., January 19, 2001; 276(4): 2372 - 2379. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Molecular and Cellular Proteomics |
| Journal of Lipid Research | ASBMB Today |
