UvsY is the phage T4 recombination mediator protein, and structural and biophysical studies provide insights into its
role in T4 homologous recombination. During T4 homologous recombination, the UvsX recombinase must compete
with the prebound gp32 single-stranded binding protein for DNA-binding sites and T4 UvsY Protein stimulates this filament nucleation
event (1). UvsY is a 15.8-kDa protein with properties that are consistent with its role as mediator; it stimulates
the DNA-dependent ATPase activity of UvsX, lowers the critical concentration of UvsX that is required for activity,
and promotes strand exchange (2, 3). UvsY efficiently promotes the UvsX-catalyzed strand invasion reaction by recruiting
to ssDNA–gp32 complexes, promotes the release of gp32, and favors the binding of UvsX.

Protein Purity
The physical purity of this enzyme is ≥98% as assessed by
SDS-PAGE with Coomassie® blue staining (Fig. 1).

Product Source
E. coli BL21 (DE3) strain expressing T4 UvsY gene with an Nterminal
GST tag. This GST tag does not have any effect on
UvsY activity.

Product Includes
UvsY protein
10X UvsY Reaction Buffer

1x UvsY reaction buffer composition
20 mM Tris-acetate
100 mM Potassium acetate
10 mM Magnesium acetate
1 mM DTT
pH 7.8 @ 25ºC

Storage Buffer
50 mM Tris-HCl
50 mM KCl
1 mM DTT
0.1 mM EDTA
50% Glycerol
pH 7.5 @ 25ºC

Storage Temperature

Quality Control assays
UvsY is free from detectable nuclease activities.

1. Beernink HT, Morrical SW. RMPs: Recombination/
replication mediator proteins. Trends Biochem Sci. 1999;24
2. Hashimoto K, Yonesaki T. The characterization
of a complex of three bacteriophage T4 recombination
proteins, uvsX protein, uvsY protein, and
gene 32 protein, on single-stranded DNA. J Biol
Chem. 1991;266(8):4883–4888.
3. Beernink HT, Morrical SW. The uvsY recombination
protein of bacteriophage T4 forms hexamers
in the presence and absence of single-stranded
DNA. Biochemistry. 1998;37(16):5673–56813572 3575