The thioredoxin binding domain of bacteriophage T7 DNA polymerase confers processivity on Escherichia coli DNA polymerase I
AUTOR(ES)
Bedford, Ella
FONTE
The National Academy of Sciences of the USA
RESUMO
Bacteriophage T7 DNA polymerase shares extensive sequence homology with Escherichia coli DNA polymerase I. However, in vivo, E. coli DNA polymerase I is involved primarily in the repair of DNA whereas T7 DNA polymerase is responsible for the replication of the viral genome. In accord with these roles, T7 DNA polymerase is highly processive while E. coli DNA polymerase I has low processivity. The high processivity of T7 DNA polymerase is achieved through tight binding to its processivity factor, E. coli thioredoxin. We have identified a unique 76-residue domain in T7 DNA polymerase responsible for this interaction. Insertion of this domain into the homologous site in E. coli DNA polymerase I results in a dramatic increase in the processivity of the chimeric DNA polymerase, a phenomenon that is dependent upon its binding to thioredoxin.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=19538Documentos Relacionados
- Escherichia coli thioredoxin: a subunit of bacteriophage T7 DNA polymerase.
- Genetic analysis of the interaction between bacteriophage T7 DNA polymerase and Escherichia coli thioredoxin.
- Effect of manganese ions on the incorporation of dideoxynucleotides by bacteriophage T7 DNA polymerase and Escherichia coli DNA polymerase I.
- Insertion of the T3 DNA polymerase thioredoxin binding domain enhances the processivity and fidelity of Taq DNA polymerase
- A unique loop in T7 DNA polymerase mediates the binding of helicase-primase, DNA binding protein, and processivity factor