FIG. 3.

Long-range PCR products. PCR products, not digested (A) or digested with ClaI (B), were electrophoresed on a 1% agarose gel in the presence of ethidium bromide. ClaI-restricted PCR product was subjected to Southern hybridization analysis using DIG-labelled probes specific for cps19fC (C) or cps19fL (D). The probes specific for cps19fC and cps19fL correspond to nucleotides 2380 to 2998 and 11539 to 12493 of the cps19f sequence (17). The molecular size standards are shown on the right-hand side of the figure and correspond to HindIII-digested λ phage DNA.