Evaluation of the effectiveness and safety of the thermo-treatment process to dispose of recombinant DNA waste from biological research laboratories.
The discharge of recombinant DNA waste from biological laboratories into the eco-system may be one of the pathways resulting in horizontal gene transfer or "gene pollution". Heating at 100 degrees C for 5-10 min is a common method for treating recombinant DNA waste in biological research laboratories in China. In this study, we evaluated the effectiveness and the safety of the thermo-treatment method in the disposal of recombinant DNA waste. Quantitative PCR, plasmid transformation and electrophoresis technology were used to evaluate the decay/denaturation efficiency during the thermo-treatment process of recombinant plasmid, pET-28b. Results showed that prolonging thermo-treatment time could improve decay efficiency of the plasmid, and its decay half-life was 2.7-4.0 min during the thermo-treatment at 100 degrees C. However, after 30 min of thermo-treatment some transforming activity remained. Higher ionic strength could protect recombinant plasmid from decay during the treatment process. These results indicate that thermo-treatment at 100 degrees C cannot decay and inactivate pET-28b completely. In addition, preliminary results showed that thermo-treated recombinant plasmids were not degraded completely in a short period when they were discharged into an aquatic environment. This implies that when thermo-treated recombinant DNAs are discharged into the eco-system, they may have enough time to re-nature and transform, thus resulting in gene diffusion.
Li
Meng-Nan
MN
State Key Laboratory of Pollution Control and Resources Reuse, School of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
Zheng
Guang-Hong
GH
Wang
Lei
L
Xiao
Wei
W
Fu
Xiao-Hua
XH
Le
Yi-Quan
YQ
Ren
Da-Ming
DM
D002681:China; D004274:DNA, Recombinant / Q000302:isolation & purification* / Q000378:metabolism / Q000633:toxicity; D004586:Electrophoresis; D006361:Heating; D007753:Laboratories; D009994:Osmolar Concentration; D010957:Plasmids; D016133:Polymerase Chain Reaction; D012106:Research; D017751:Safety Management / Q000379:methods*; D013997:Time Factors; D018505:Waste Management / Q000379:methods*
D004274:DNA, Recombinant