FIG. 1.

Construction of an infectious PCV2 molecular DNA clone. The relative positions of the primer pair used to amplify the complete PCV2 genome are indicated by the arrows (reverse primer, R-PCVSAC2; forward primer, F-PCVSAC2). The PCV2 genomic DNA amplified by PCR is digested with the SacII restriction enzyme and purified. The purified and SacII-digested genomic DNA was ligated to form concatemers. Ligated concatemers were separated by gel electrophoresis; the tandem genome dimmer of PCV2 was purified and cloned into the pSK vector, which is predigested with the SacII enzyme to produce a molecular PCV2 DNA clone.