From 2007.igem.org

Mon, 25th June to Thu, 05th July 2007

we gained the dhfr1 fragment by using PCR. we used an improper plasmid for the first PCR so we had to repeat it several times, using another plasmid

Wed, 20th June to Thu, 28th June 2007

Planning a new Plasmid containing splitted Dhfr Fragments instead of the lactamase
we cutted the 320d blac1-wz-blac2 plasmid (used as vector) and a 300d dhfr2 plasmid (insert) with HindIII and SpeI, ligated them and transformed into XL-1 blue E.coli cells to get a 320d blac1-wz-dhfr2 plasmid