The formation of p81120, plasmid vehical

The formation of p81120 , plasmid vehical
PLasmd pHHIO hai two Eco RI siIc and ii was desirable to retain only one of them, that Iosated between the iw control region and the Tc gmc. The Sac and Tc promOters in pBHIO are only 40 base pairs apart and addition of RNA polymcrasc effectively protects this site from Eco .RI digcsion. This is because in the absence of ribonucleotidc triphosphates the RNA polymciase does nat Initiate trans4.Tip( on and remains firmly bound to the pamotcrs. The second Lco RI s.c. howcscr is esposed. After addition of RNA polymcrasc. p111110 was cleascd with L’co RI and the singk-suandcd taiLs rcmoscd with SI ctonuckase. The linear duples so produced was circularized with T4 DNA Iigasc to generate pBH2O.