[Expression of the PAC gene of S. mutans in S. lactis]

Expression of the pac gene in S. lactis were analyzed by dot immunoblotting with rabbit anti-PAc serum. The amount of PAc produced by S. lactis HL107 (pLF107) was measured. This result indicated that a small amount of rPAc was detected in the culture supernatant and cell homogenate of S. lactis HL107 (pLF107) but not in the control strain S. lactis LM0230. The amount of rPAc in S.lacits HL107 (pLF107) was six times lower than that in S. mutans Ingbritt. Expression of cloned pac gene in S. lactis was also confirmed in this result.