Genetic engineering for degradation of TCP in groundwater
A genetically modified organism is constructed by Ghufrana Samin for the degradation of a toxic compound and applied successfully in a lab-scale bioreactor to remove 1,2,3-trichlororpropane (TCP)-contaminated groundwater.
TCP is a toxic compound that has caused serious groundwater pollution at chemical waste disposal sites. The availability of a bacterium that can degrade this compound would allow the development of bioreactors for TCP removal from contaminated groundwater.
TCP-degrading strain
A possible degradation pathway would start with hydrolytic dehalogenation of TCP to 2,3-dichloro-1-propanol (DCP), followed by further oxidative metabolism. In the first part of her study, Samin isolated a strain of Pseudomonas putida from contaminated soil on basis of its capacity to utilize DCP as growth substrate. To transform TCP into DCP, she expressed an engineered haloalkane dehalogenase (DhaA31) constitutively under control of the dhlA promoter and introduced into the genome of the DCP-degrading bacterium by using a transposon delivery system. The transposon-located antibiotic marker was subsequently removed. Growth of the engineered bacterium on TCP was indeed observed. The genetically engineered TCP-degrading strain is stable, free of any additional plasmid-encoded antibiotic resistance marker and has the ability to completely mineralize TCP with quantitative stoichiometric release of inorganic chloride.
More than 80 percent removed TCP
The application of the strain in lab-scale bio-reactors was also investigated by Samin. Her results indicate that with the constructed strains, the reactor removed TCP (80-90%) at various residence times (116 h and 23 h). During the construction of the genetically engineered bacterium, she found that haloalkane dehalogenase was exported to the periplasm even though no signal sequence was present. The results indicate the potential use of DhaA as a tag for the periplasmic export of heterologously expressed proteins.
Dissertation: Genetic engineering for trichloropropane degradation
PhD ceremony: Ms. G. Samin, 11.00 uur, Academiegebouw, Broerstraat 5, Groningen
Last modified: | 31 January 2017 11.13 p.m. |
More news
-
16 March 2023
Jacquelien Scherpen winner of Prince Friso Engineering Award 2023
Prof. Jacquelien Scherpen, Director of the Groningen Engineering Center, at the Faculty of Science and Engineering (UG), has been voted Engineer of the Year 2023 by the expert jury. She received the Prince Friso Engineering Award 2023 yesterday, 15...
-
16 March 2023
Ben Feringa awarded Honorary Doctorate from Bratislava University
On March 15, 2023, the Slovak University of Technology in Bratislava awarded the title of "Doctor honoris causa" to Nobel laureate Ben Feringa from the Stratingh Institute for Chemistry (University of Groningen).
-
10 March 2023
ENW Science-M grant for Andreas Milias-Argeitis
Prof. Andreas Milias-Argeitis of the Groningen Biomolecular Sciences and Biotechnology Institute (GBB, University of Groningen) has been awarded an Open Competition Science-M grant by the Dutch Research Council (NWO). He receives an M1 grant of EUR...