Pnicillinase를 분필하는 Streptomyces bobili YS-40균주의 plasmid DNA를 phemol방법으로 유출하여 Bocillus subtilis IAM 12118균주에 형질 전환시켜서 penicillin 내성 plasmid DNA가 표현되게 하였다. 형질전환에 미치는 최적 pH와 온도는 각각 7.0, 3$0^{circ}C$으로 나타났다. DNA와 Competent cell을 20분 이상 접촉시킴으로서 형질전환이 잘 일어났으며 DNA의 농도가 증가할수록 transformant의 수도 증가했다. DNA inhibitor 로 사용되는 lysine 의 첨가로 형질전환의 빈도가 약 6배정도 상승되었으며 chloramphenicol은 형질전환의 빈도에 별 영향을 미치지 않았다.
The penicillin resistant plasmid DNA was prepared from Streptomyces bobili YS-40, producing penicillinase, by the phenol extraction method and introduced into Bocillus subtilis IAM 12118 by the transformation procedure of Mahler method. The optimal pH and temperature on the transformation was 7.0, 3$0^{circ}C$ respectively. Above 20 minutes contact of plasmid DNA and recipient cell was shown the high transformation frequency. The transformant of penicillin resistance was proportionally increased as increase of the DNA concentration. The addition of lysine in transformation system increased the transformation frequency about 6-fold and the addition of the chloramphenicol did not affect the transformation frequency.
