Microbial
Biotechnology |
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Environmental Biotechnology |
Electronic Journal of Biotechnology ISSN: 0717-3458 |
Vol.
12 No. 4, Issue of October 15, 2009 |
© 2009 by Pontificia Universidad Católica
de Valparaíso -- Chile |
Received January 31, 2009 / Accepted July 12, 2009 |
DOI: 10.2225/vol12-issue4-fulltext-11 |
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Degradation of methomyl by the novel
bacterial strain Stenotrophomonas maltophilia M1
Mervat S. Mohamed
Faculty of Science
Cairo University, Egypt
E-mail: mervat@cu.edu.eg
Financial support: Cairo University.
Keywords: carbamate; methomyl; plasmid; SPE-LC-ESI-MS; Stenotrophomonas.
Abbreviations: |
SPE-LC-ESI-MS: solid
phased extraction coupled to capillary liquid chromatography-electrospray
ionization-mass spectrometry
LB: Luria Bertani
MSM: minimal salt medium
PCR: polymerase chain reaction |
The use of microorganisms in the degradation
and detoxification of many toxic xenobiotics, especially pesticides, is an
efficient tool for the decontamination of polluted sites in the environment. A novel
bacterial strain (M1) was isolated from several water samples contaminated with
methomyl which is capable of degrading methomyl pesticide (1000 ppm) in the
presence of 0.05% glucose. These water samples were collected from different
irrigation sites in Egypt where methomyl is heavily applied. The partial
sequence of 16SrRNA gene of the isolate showed the highest similarity to Stenotrophomonas maltophilia. Restriction fragment patterns of isolated plasmid DNA
showed that this strain harbours two different plasmids PMa (8Kb) and PMb (5Kb). PMb succeeded to be transferred to Escherichia
coli DH5α strain. This transformed strain (M2) acquired the ability to
grow in the presence of methomyl (1000 ppm) and 0.05% glucose. So it was
deduced that the gene responsible for the degradation process was encoded by
this plasmid. The
ability of the two strains M1 and M2 to degrade methomyl was detected by using solid phased extraction coupled to
capillary liquid chromatography-electrospray ionization-mass spectrometry (SPE-LC-ESI-MS).
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