The two synthetic DNA duplexes, the one as control having an optimized sequence and the other possessing partially random sequence, corresponding to the region of ribosome binding site were synthesized through the phosphite method on solid support. The synthetic RBS DNA duplexes having Eco RI and HindIII cohesive ends were cloned into the previously engineered gap in plasmid pMKT2 possessing 1pp promoter and the β-galactosidase gene. This construction gave a direct screening system for the expression level on the plate by the difference of color intensities of colonies formed. The colonies which showed the; high expression of β-galactosidase are characterized in terms of the activities and sequence. The effects of the sequence on RBS region to the translational efficiency are discussed.
pIN lll vector 의 ribosome binding sequence 를 갖는 DNA fragment 와 random 하게 합성한 RBS DNA fragment 를 lpp promoter 와 β-galactosidase 유전자를 갖도록 미리 만들어 놓은 pMKT2 vector 에 넣었다. 이러한 실험은 plate 상에서 β-galactosidase gene 의 expression level 에 따라 색깔의 정도 차이가 나는 colonies 를 activity 와 sequence 에 따라 그 특성을 조사하고 translation 효율에 미치는 RBS sequence 의 영향을 보았다.
