HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 275, Issue 36, 27865-27873, September 8, 2000

This Article Full Text Full Text (PDF) All Versions of this Article: 275/36/27865    most recent M004104200v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Jezewska, M. J. Articles by Bujalowski, W. Search for Related Content PubMed PubMed Citation Articles by Jezewska, M. J. Articles by Bujalowski, W. Social Bookmarking                      What's this?

Escherichia coli Replicative Helicase PriA Protein-Single-stranded DNA Complex
STOICHIOMETRIES, FREE ENERGY OF BINDING, AND COOPERATIVITIES^*

Maria J. Jezewska, Surendran Rajendran, and Wlodzimierz Bujalowski

From the Department of Human Biological Chemistry and Genetics, the University of Texas Medical Branch, Galveston, Texas 77555-1053

Analyses of interactions of the Escherichia coli replicative helicase, PriA protein, with a single-stranded (ss) DNA have been performed, using the quantitative fluorescence titration technique. The stoichiometry of the PriA helicase·ssDNA complex has been examined in binding experiments with a series of ssDNA oligomers. The total site-size of the PriA·ssDNA complex, i.e. the maximum number of nucleotide residues occluded by the PriA helicase in the complex, is 20 ± 3 residues per protein monomer. However, the protein can efficiently form a complex with a minimum of 8 nucleotides. Thus, the enzyme has a strong ssDNA-binding site that engages in direct interactions with a significantly smaller number of nucleotides than the total site-size. The ssDNA-binding site is located in the center of the enzyme molecule, with the protein matrix protruding over a distance of ~6 nucleotides on both sides of the binding site. The analysis of the binding of two PriA molecules to long oligomers was performed using statistical thermodynamic models that take into account the overlap of potential binding sites, cooperative interactions, and the protein·ssDNA complexes with different stoichiometries. The intrinsic affinity depends little upon the length of the ssDNA. Moreover, the binding is accompanied by weak cooperative interactions.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				T. Mizukoshi, T. Tanaka, K.-i. Arai, D. Kohda, and H. Masai A Critical Role of the 3' Terminus of Nascent DNA Chains in Recognition of Stalled Replication Forks J. Biol. Chem., October 24, 2003; 278(43): 42234 - 42239. [Abstract] [Full Text] [PDF]

				A. I. Alexandrov, M. R. Botchan, and N. R. Cozzarelli Characterization of Simian Virus 40 T-antigen Double Hexamers Bound to a Replication Fork. THE ACTIVE FORM OF THE HELICASE J. Biol. Chem., November 15, 2002; 277(47): 44886 - 44897. [Abstract] [Full Text] [PDF]

				M. K. Levin and S. S. Patel Helicase from Hepatitis C Virus, Energetics of DNA Binding J. Biol. Chem., August 9, 2002; 277(33): 29377 - 29385. [Abstract] [Full Text] [PDF]

				P. D. Morris, A. J. Tackett, K. Babb, B. Nanduri, C. Chick, J. Scott, and K. D. Raney Evidence for a Functional Monomeric Form of the Bacteriophage T4 Dda Helicase. Dda DOES NOT FORM STABLE OLIGOMERIC STRUCTURES J. Biol. Chem., June 1, 2001; 276(23): 19691 - 19698. [Abstract] [Full Text] [PDF]