The T4 Gp59 protein plays critical roles in the assembly of the phage replisome and its coordination with homologous recombination (1, 2). Gp59 is a versatile mediator protein that loads the replicative DNA helicase, Gp41, onto replication forks and recombination intermediates that are generated during different stages of the T4 infection cycle in its host organism, Escherichia coli. In addition to helicase loading, Gp59 has been shown to perform a second function: polymerase blocking (3-5). Gp59 inhibits the DNA synthesis and exonuclease activities of the phage polymerase, Gp43, until the replisome is fully assembled (3).
The physical purity of this enzyme is ≥98% as assessed by SDS-PAGE with Coomassie® blue staining (Fig. 1).
- coli BL21 (DE3) strain expressing T4 gp59 gene.
- T4 gp59 protein
- 10X gp59 reaction buffer
1x gp59 reaction buffer composition
20 mM Tris-acetate
100 mM Potassium acetate
10 mM Magnesium acetate
1 mM DTT
pH 7.8 @ 25ºC
50 mM Tris-HCl
50 mM KCl
1 mM DTT
0.1 mM EDTA
pH 7.5 @ 25ºC
Quality Control assays
Gp59 is free from detectable nuclease activities.
- Jones, C. E., Mueser, T. C., Dudas, K. C., Kreuzer, K. N., and Nossal, N. G. (2001) Proc. Natl. Acad. Sci. U.S.A. 98, 8312–8318Patel SS, Picha KM. Annu Rev Biochem. 2000;69: 651–697
- Beernink, H. T., and Morrical, S. W. (1999) Trends Biochem. Sci. 24, 385–389Schrock RD, Alberts B. J Biol Chem. 1996;271:16678–16682.
- Xi, J., Zhang, Z., Zhuang, Z., Yang, J., Spiering, M. M., Hammes, G. G., and Benkovic, S. J. (2005) Biochemistry 44, 7747–7756
- Xi, J., Zhuang, Z., Zhang, Z., Selzer, T., Spiering, M. M., Hammes, G. G., and Benkovic, S. J. (2005) Biochemistry 44, 2305–2318
- Nelson, S.W., Yang J., and Benkovic, S. J. (2006) J. Biol. Chem. 281, 8697–8706