The Red system of bacteriophage λ consists of three proteins that promote DNA recombination initiated at dsDNA breaks or at the overlapping ends of the linear λ chromosome (1). The exo gene (redα) encodes λ exonuclease, a 24-kDa protein with 5´→3´ exonuclease activity (2). The bet gene (redβ) encodes the 29-kDa β protein, which binds ssDNA and promotes annealing of complementary strands (3). The gam gene encodes the 16-kDa γ protein, which binds and inhibits host nuclease enzymes (4).
• Bind ssDNA
• Promote annealing of complementary strands
• Promote some RecA-like strand exchange and invasion reactions in vitro
Quality control is performed following the production of each new lot of product to ensure that it meets the quality standards and specifications designated for the product.
Lambda beta is free from detectable nuclease and RNase activities.
The physical purity of this enzyme is ≥99% as assessed by SDS-PAGE with Coomassie® blue staining (see figure below).
E. coli cells carrying λ redβ gene.
Contents & Storage
• Lambda beta
• 10x Lambda beta reaction buffer
Store all contents at -20 °C.
10x Lambda beta reaction buffer
670 mM Glycine-KOH 25 mM MgCl2 500 μg/ml BSA pH 9.4 @ 25°C.
50 mM Tris-HCl (pH 7.5), 0.1 mM EDTA, 1 mM β-mercaptoethanol, 1 mM DTT and 50% (v/v) glycerol.
Inactivated by heating at 70°C for 20 min.
1. Poteete AR. FEMS Microbiol Lett 2001; 201:9 -14.
2. Little, J.W. (1981). Gene Ampli. Anal. 2, 135-145.
3. Kmiec E, Holloman WK. J Biol Chem 1981; 256:12636 -12639.
4. Marsic N, Roje S, Stojiljkovic I, Salaj-Smic E, Trgovcevic Z. J Bacteriol 1993;175:4738 -4743.3611 3613