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Title: Characterization and modification of phage T7 DNA polymerase for use in DNA sequencing; Progress report, June 1, 1990--May 31, 1993

Technical Report ·
DOI:https://doi.org/10.2172/142503· OSTI ID:142503

This project focuses on the DNA polymerase (gene 5 protein) of phage T7 for use in DNA sequence analysis. Gene 5 protein interacts with accessory proteins to acquire properties essential for DNA replication. One goal is to understand these interactions in order to modify the proteins for use in DNA sequencing. E. coli thioredoxin, binds to gene 5 protein and clamps it to a primer-template. They have analyzed the binding of gene 5 protein-thioredoxin to primer-templates and have defined the optimal conditions to form an extremely stable complex with a dNTP in the polymerase catalytic site. The spatial proximity of these components has been determined using fluorescence emission anisotropy. The T7 DNA binding protein, the gene 2.5 protein, interacts with gene 5 protein and gene 4 protein to increase processivity and primer synthesis, respectively. Mutant gene 2.5 proteins have been isolated that do not interact with T7 DNA polymerase and can not support T7 growth. The nucleotide binding site of the T7 helicase has been identified and mutations affecting the site provide information on how the hydrolysis of NTPs fuel its unidirectional translocation. The sequence, GTC, has been shown to be necessary and sufficient for recognition by the T7 primase. The T7 gene 5.5 protein interacts with the E. coli nucleoid protein, H-NS, and also overcomes the phage {lambda} rex restriction system.

Research Organization:
Harvard Medical School, Boston, MA (United States). Dept. of Biological Chemistry and Molecular Pharmacology
Sponsoring Organization:
USDOE, Washington, DC (United States)
DOE Contract Number:
FG02-88ER60688
OSTI ID:
142503
Report Number(s):
DOE/ER/60688-6; ON: DE94008550; TRN: AHC29407%%35
Resource Relation:
Other Information: PBD: [1993]
Country of Publication:
United States
Language:
English