Recombinant DNA approaches to enhance activity of the pathway for degradation of the toxic

Recombinant DNA Approaches

Recombinant DNA approaches to enhance activity of the pathway for degradation of the toxic pollutant styrene in the bacteria Pseudomonas putida CA-3.

Researchers:  Mark O'Mahony, Dr Niall O'Leary, Prof Alan Dobson
Telephone:  021 4901970

Funding body:  EPA
Programme:  STRIVE
Project type:  Post-doc
Period:  October 2007-October 2009

left:  Indole-to-indigo conversion by the styrene degradation genes in P. putida CA-3

Project Description

Pseudomonas putida CA-3 is a bioreactor isolate capable of degrading the toxic aromatic pollutant styrene.  However, in addition to styrene mineralisation to CO2 and H2O), via acetyl-CoA, this strain is also capable of redirecting styrene catabolism to biodegradable plastic production, (i.e. Poly-hydroxyalkanoate), under appropriate growth conditions.  This capability has considerable biotechnological significance as it facilitates the conversion of toxic waste to an eco-friendly, value added product.  The current project seeks to enhance the ability of P. putida CA-3 to degrade styrene  by investigating the flux through the pathway, identifying bottlenecks and applying recombinant DNA approaches to overcome them.  Research outputs from this study will include recombinant strains with enhanced styrene degradation profiles and increased PHA accumulation capacities.

Selected Group Publications on Styrene Degradation:

O'Leary, N.D., A. Mooney, M. M. O'Mahony and A.D.W. Dobson.  2008.  Functional characterisation of essential domains within the styrene histidine kinase sensor protein StyS; a role for intracellular sensing in the transcriptional regulation of the sty operon.  In Prep.

Mooney, A., N.D. O'Leary, and A.D.W. Dobson.  2006.  Cloning and functional characterisation of the styE gene involved in styrene transport in Pseudomonas putida CA-3.  Appl. Environ. Microbiol.  72:1302-9.

O'Leary, N.D., K.E. O'Connor, P. Ward, M. Goff and A.D.W. Dobson.  2005.  Genetic characterisation of accumulation of polyhydroxyalkanoate from styrene in Pseudomonas putida CA-3.  Appl. Environ. Microbiol. 71:4380-7.

O'Leary, N.D., K.E. O'Connor and A.D.W. Dobson.  2002.  Biochemistry, genetics and physiology of microbial styrene degradation.  FEMS Microbiol Rev. 26:403-17.

O'Leary, N.D., W.A. Duetz, A.D.W. Dobson and K.E. O'Connor.  2002.  Induction and repression of the sty operon in Pseudomonas putida CA-3 during growth on phenylacetic acid under organic and inorganic nutrient limiting continuous culture conditions.  FEMS Microbiol.  Lett. 208: 263-8.


Environmental Research Institute

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