Two modes of interaction of the single-stranded DNA-binding protein of bacteriophage T7 with the DNA polymerase-thioredoxin complex

Handle URI:
http://hdl.handle.net/10754/561475
Title:
Two modes of interaction of the single-stranded DNA-binding protein of bacteriophage T7 with the DNA polymerase-thioredoxin complex
Authors:
Ghosh, Sharmistha; Hamdan, Samir; Richardson, Charles C.
Abstract:
The DNA polymerase encoded by bacteriophage T7 has low processivity. Escherichia coli thioredoxin binds to a segment of 76 residues in the thumb subdomain of the polymerase and increases the processivity. The binding of thioredoxin leads to the formation of two basic loops, loops A and B, located within the thioredoxin-binding domain (TBD). Both loops interact with the acidic C terminus of the T7 helicase. A relatively weak electrostatic mode involves the C-terminal tail of the helicase and the TBD, whereas a high affinity interaction that does not involve the C-terminal tail occurs when the polymerase is in a polymerization mode. T7 gene 2.5 single-stranded DNA-binding protein (gp2.5) also has an acidic C-terminal tail. gp2.5 also has two modes of interaction with the polymerase, but both involve the C-terminal tail of gp2.5. An electrostatic interaction requires the basic residues in loops A and B, and gp2.5 binds to both loops with similar affinity as measured by surface plasmon resonance. When the polymerase is in a polymerization mode, the C terminus of gene 2.5 protein interacts with the polymerase in regions outside the TBD.gp2.5 increases the processivity of the polymerase-helicase complex during leading strand synthesis. When loop B of the TBD is altered, abortive DNA products are observed during leading strand synthesis. Loop B appears to play an important role in communication with the helicase and gp2.5, whereas loop A plays a stabilizing role in these interactions. © 2010 by The American Society for Biochemistry and Molecular Biology, Inc.
KAUST Department:
Biological and Environmental Sciences and Engineering (BESE) Division; Bioscience Program
Publisher:
American Society for Biochemistry and Molecular Biology
Journal:
Journal of Biological Chemistry
Issue Date:
6-Apr-2010
DOI:
10.1074/jbc.M110.107656
PubMed ID:
20375019
PubMed Central ID:
PMC2878571
Type:
Article
ISSN:
00219258
Additional Links:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2878571
Appears in Collections:
Articles; Bioscience Program; Biological and Environmental Sciences and Engineering (BESE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorGhosh, Sharmisthaen
dc.contributor.authorHamdan, Samiren
dc.contributor.authorRichardson, Charles C.en
dc.date.accessioned2015-08-02T09:12:18Zen
dc.date.available2015-08-02T09:12:18Zen
dc.date.issued2010-04-06en
dc.identifier.issn00219258en
dc.identifier.pmid20375019en
dc.identifier.doi10.1074/jbc.M110.107656en
dc.identifier.urihttp://hdl.handle.net/10754/561475en
dc.description.abstractThe DNA polymerase encoded by bacteriophage T7 has low processivity. Escherichia coli thioredoxin binds to a segment of 76 residues in the thumb subdomain of the polymerase and increases the processivity. The binding of thioredoxin leads to the formation of two basic loops, loops A and B, located within the thioredoxin-binding domain (TBD). Both loops interact with the acidic C terminus of the T7 helicase. A relatively weak electrostatic mode involves the C-terminal tail of the helicase and the TBD, whereas a high affinity interaction that does not involve the C-terminal tail occurs when the polymerase is in a polymerization mode. T7 gene 2.5 single-stranded DNA-binding protein (gp2.5) also has an acidic C-terminal tail. gp2.5 also has two modes of interaction with the polymerase, but both involve the C-terminal tail of gp2.5. An electrostatic interaction requires the basic residues in loops A and B, and gp2.5 binds to both loops with similar affinity as measured by surface plasmon resonance. When the polymerase is in a polymerization mode, the C terminus of gene 2.5 protein interacts with the polymerase in regions outside the TBD.gp2.5 increases the processivity of the polymerase-helicase complex during leading strand synthesis. When loop B of the TBD is altered, abortive DNA products are observed during leading strand synthesis. Loop B appears to play an important role in communication with the helicase and gp2.5, whereas loop A plays a stabilizing role in these interactions. © 2010 by The American Society for Biochemistry and Molecular Biology, Inc.en
dc.publisherAmerican Society for Biochemistry and Molecular Biologyen
dc.relation.urlhttp://www.ncbi.nlm.nih.gov/pmc/articles/PMC2878571en
dc.titleTwo modes of interaction of the single-stranded DNA-binding protein of bacteriophage T7 with the DNA polymerase-thioredoxin complexen
dc.typeArticleen
dc.contributor.departmentBiological and Environmental Sciences and Engineering (BESE) Divisionen
dc.contributor.departmentBioscience Programen
dc.identifier.journalJournal of Biological Chemistryen
dc.identifier.pmcidPMC2878571en
dc.contributor.institutionDepartment of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 240 Longwood Ave, Boston, MA 02115, United Statesen
kaust.authorHamdan, Samiren

Related articles on PubMed

All Items in KAUST are protected by copyright, with all rights reserved, unless otherwise indicated.