Revision as of 17:05, 21 October 2019

Cytosine deaminase

An enzyme that oxidizes 5-fluorouracil to 5-fluorouracil

Usage and Biology

result

Cytosine deaminase (CD) is the enzyme that can transform cytosine into uracil. CD’s function is to convert nontoxic 5-flucytosine (5-FC) into toxic 5-fluorouracil (5-FU), which has an extreme damage to the bacteria.

We added gradient of 5-FC culturing the bacteria and monitored their growth.

Fig.1 Growth of E.coli at different concentration of 5-FC. Fostered the bacteria (keeping the quantity of the bacteria same before 1% passaging : 2 μl bacteria, OD=3.5) with a concentration gradient of 5-FC in the LB media (containing 50µg/ml Amp and Str): 500 mg/l, 250 mg/l, 100 mg/l, 50 mg/l, 25 mg/l, 0 mg/l. A. The bacteria (E.coli) using T7 to express CD. B. The bacteria (E.coli) can`t express CD.

As a positive control, we added gradient of 5-FU culturing the bacteria and monitored their growth.

Fig.2 Growth of bacteria at different concentrations of 5-FU. Fostered the bacteria (keeping the quantity of the bacteria same before 1% passaging: 2 μl bacteria, OD=3.5) with a concentration gradient of 5-FC in the LB media (containing 50 µg/ml Amp and Str): 500 mg/l, 250 mg/l, 100 mg/l, 50 mg/l, 25 mg/l, 0 mg/l. A. The bacteria using T7 to express CD. B. The original bacteria that without the CD expression plasmid.

For more details about the part, please visit NEFU_China 2019 wiki.

Sequence and Features