Figure 5.

Recombination products of n-site I. The panel on the left summarizes the experimental design; a labelled 50 bp n-site I is reacted together with excess unlabelled 70 bp n-site I. 50 bp n-site I (20 nM), ³²P-labelled at either the left or the right end as indicated by the cartoons above the lanes, was mixed with an excess (80 nM) of unlabelled 70 bp n-site I and treated with NM resolvase at 37°C for 1 h. Reactions were stopped by treatment with 0.1% SDS (and 1 mg/ml protease K in lanes 3 and 6), and products were separated on an SDS-polyacrylamide gel. Product assignments are indicated by the small cartoons on the right of the gel. SSB, single-strand break product; rec., recombinant. Half-site products HS-L, HS-R and HS-R* are described in the text. The SSB products may be formed by incomplete ligation or strand cleavage of a 60 bp recombinant site, or of a 50 bp ‘recombinant’ site comprising two 25 bp labelled HS-R* half-sites.