Fig. 5.

Hairpin formation does not take place with the authentic STC. Unlabeled duplex Mu end DNA (100 nM) was reacted with MuA (300 nM) in the presence of a limiting concentration of end-labeled mismatch containing target DNA (20 nM). MuB and ATP were present in the reaction to enhance strand transfer efficiency. The target DNA had a 3′ or a 5′ end label as indicated. Products were analyzed by alkaline agarose gel electrophoresis. Positions of the substrate and primary products, as well as the expected positions of the hairpin products, are indicated.