Figure 1. Construction and verification of plasmid pCIA-P. (A) The A- and P-regions of PAc protein of S. mutans was cloned into eukaryotic expression vector pCI to obtain the recombinant plasmid pCIA-P. (B) Restriction enzyme digestion of pCIA-P and pCI. The sizes of pCIA-P, A-P fragment, and pCI were 6.2 kb, 2.2 kb, and 4.0 kb, respectively. Lane 1: pCI with XhoI digestion. Lane 2: pCIA-P with Bgl I digestion. Lane 3: pCIA-P with XhoI digestion. Lane 4: pCIA-P with Xho I/Sal I digestion. Lane 5: DNA/HindIII marker.