Mr Andrew Steven

Research Technician

Areas of interest: Wolbachia bacteria of filarial nematodes as an anti-filarial drug target for lymphatic filariasis (elephantiasis) and onchocerciasis (river blindness).

Background
I completed my BSc (Hons) in Applied Biology in 1994 from Liverpool John Moores University.
I joined the School of Tropical Medicine in 1989 in the department of Medical Entomology as a laboratory technician maintaining the mosquito colonies. In 2001, joined Dr Steven Sinkins group and was involved in a project exploring the effect of the symbiont Wolbachia on cytoplasmic incompatibility between mosquitoes In 2003, I joined  Professor Janet Hemingway’s group to work on insecticide resistant Culex quinquefasciatus mosquitoes investigating known and novel mutations in the acetylcholinesterase gene . I also isolated the equivalent gene from Anopheles gambiae and studied expression patterns in different life stages . In 2006, joined the Enzyme Characterisation Group, to prepare  bacterial membranes for P450 expression and also expressed and purified batches of Glutathione-S-Transferase’s. I also performed recombinant protein assays for insecticide metabolism and HPLC analysis of insecticide metabolites.  In 2010, I joined the A-WOL consortium as a Research Technician, with responsibility for the running and resourcing of the Filariasis Research Laboratory. I contribute to the molecular and parasitological experimental activities including evaluation of drug screening and maintenance of parasite life cycles and vector mosquito colonies.

 

Publications

  • Sinkins SP, Walker T, Lynd AR, Steven A.R, Makepeace BL, Godfray HCJ, Parkhill J. (2005) Wolbachia variability and host effects on crossing type in Culex mosquitoes. Nature 436: 257-260.

    Surendran SN, Hawkes NJ, Steven A.R, Hemingway J, Ramasamy R. (2006) Molecular studies of Anopheles culicifacies (Diptera: Culicidae) in Sri Lanka: sibling species B and E show sequence identity at multiple loci. Eur. J. Entomol 103: 233-237

    Report for Shell in Nigeria: Insecticide resistance in the malaria vectors, and drug resistance in the malaria parasite, Plasmodium falciparum, in regions of Nigeria where Shell has permanent expatriate camps. May 2005
    Michael Coleman, Andrew Steven, Peter Mohloai, and Janet Hemingway.

    Müller, P., Warr, E., Stevenson, B. J., Pignatelli, P., Morgan, J., Steven, A., Yawson, A. E., Mitchell, S., Hemingway, J., Ranson, H., Paine, M., and Donnelly, M. J. (2008) Field-caught permethrin-resistant Anopheles gambiae s.s. over express CYP6P3, a P450 that metabolizes pyrethroids. PLoS Genet 4: e1000286

    Morou, E., Ismail, H. M., Dowd, A. J., Steven, A, Hemingway, J., Labrou, N., Paine, M., and Vontas, J. (2008) A dehydrochlorinase-based pH change assay for determination of DDT in sprayed surfaces, Anal Biochem 378, 60-64.

    Andrew J. Dowd, Andrew Steven, Evangelia Morou, Janet Hemingway, John Vontas, Mark J.I. Paine (2009) A simple glutathione transferase-based colorimetric endpoint assay for insecticide detection. Enzyme and Microbial Technology,45: 164-168

    John Vontas, Andrew J. Dowd, Evangelia Morou, Hanafy Ismael, Andrew Steven, Janet Hemingway, Mark Paine. (2009) Simple tests for measuring insecticides in treated/sprayed surfaces.Poster presentation in Nairobi for IVCC

    Nelson Cuamba, John Morgan, Helen Irving, Andrew Steven and Charles S Wondji (2010) High level of Pyrethroid resistance in an Anopheles funestus population of the Chokwe district in Mozambique. PLoS ONE 5(6): e11010.

    Dowd, A.J. , Morou, E. , Steven, A. , Ismael, H. , Labrou, N. , Paine, M.J.I. , Vontas, J (2010) Development of a colorimetric pH assay for the quantification of pyrethroids based on Glutathione-S-Transferase. International Journal of Environmental Analytical Chemistry 90 (12) 922 - 933

    Pyrethroid and DDT resistance in an Anopheles funestus population from Uganda (2010) John Morgan, Helen Irving, Loyce M. Okedi, Andrew Steven and Charles S. Wondji. PLoS ONE 5(7): e11872

    A simple colorimetric assay for specific detection of glutathione-S transferase activity associated with DDT resistance in mosquitoes (2010) Morou E., Dowd A.J., Rajatileka S., Steven A., Hemingway J., Ranson H., PaineM. and Vontas J. PLoS Negl Trop Dis 4(8): e808