Dr. James M Mutunga, PhD - Mount Kenya University - Research Scientist and Lecturer

Dr. James M Mutunga

PhD

Mount Kenya University

Research Scientist and Lecturer

Thika, Central | Kenya

Main Specialties: Other

Additional Specialties: Medical Entomology, Insect Physiology & Toxicology, Arthropod Biocontainment


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Dr. James M Mutunga, PhD - Mount Kenya University - Research Scientist and Lecturer

Dr. James M Mutunga

PhD

Introduction

James is an entomologist with transdisciplinary experience in biochemistry, molecular biology, toxicology and field entomology. He has applied these fields in public health for the last 11 years primarily working on developing new control tools for malaria mosquitoes. His competencies encompass basic lab discovery in toxicology of insecticides, to applied research in semi-field systems and translational research under field systems. James Mutunga obtained a BSc (Biological Sciences; 2000), MSc in Biochemistry (2005) from Jomo-Kenyatta University in Nairobi Kenya, and PhD in Entomology (Neurotoxicology; 2007-2011) from Virginia Tech, Blacksburg, VA, USA. Prior to his PhD studies, James worked as a Senior Research Assistant in the Human Health Division of the International Centre of Insect Physiology and Ecology (icipe), where he was involved in a countrywide survey of molecular and biochemical resistance to pyrethroids in malaria mosquitoes. His PhD work involved the molecular, biochemical and toxicological evaluation of new carbamate molecules for toxicity and selectivity to An. gambiae, the African malaria mosquito. In 2011-2012, he was a postdoctoral fellow at Prof. Jeffrey Bloomquist’s lab hosted at the Emerging Pathogens Institute, Department of Entomology and Nematology, University of Florida, Gainesville. Here, James was involved in characterizing new potassium channel blockers as potential insecticides for mosquito control. He spent part of 2012 working with Genesis Labs, in Wellington, CO; but based at the project sites in India and western Kenya. This work involved testing of systemic insecticides for feed-through systems in cattle for control of zoophilic malaria mosquitoes, and was done in collaboration with KEMRI/CDC labs in western Kenya. In year 2013, he joined icipe's Human Health Division, where he coordinated a large field-based project in Islands and mainland areas of Lake Victoria, that sought to understand the vector population genetics and disease transmission dynamics of malaria mosquitoes in western Kenya. Information collected in this study provided key site-selection considerations and informed important entomological and epidemiological considerations that are required prior to the implementation of contained field studies with transgenic arthropods. This work also led to the establishment of an Arthropod Containment Level-2 (ACL-2) facility at icipe’s Thomas Odhiambo campus in western Kenya. He also worked in a Gates-funded project, together with collaborators at LSU Ag Center in Louisiana to design and test a mosquito attract-and-kill strategy that deploys new attractants, potent insect growth regulators and novel potassium channel blockers in testing adult-kill and autodissemination of IGRs to oviposition sites for larval control. He also coordinated the optimization and scale-up of integrated vector management interventions in a Biovision funded malaria project at Nyabondo, in western Kenya. In addition to undergraduate teaching and postgraduate research supervision at Mount Kenya University, James, together with his collaborators are currently undertaking research in exploring novel molecular targets of plant-derived mosquitocidal compounds, transmission blocking agents and developing new resistance-resilient tools for mosquito control.

Primary Affiliation: Mount Kenya University - Thika, Central , Kenya

Specialties:

Additional Specialties:

Research Interests:


View Dr. James M Mutunga’s Resume / CV

Experience

Feb 2013
Project Coordinator
Coordination of laboratory work and field entomology teams
Working with multiple stakeholders in field mosquito research

Publications

16Publications

264Reads

1637Profile Views

2PubMed Central Citations

Select β- and γ-branched 1-alkylpyrazol-4-yl methylcarbamates exhibit high selectivity for inhibition of versus human acetylcholinesterase.

Pestic Biochem Physiol 2018 Oct 13;151:32-39. Epub 2018 Feb 13.

Emerging Pathogens Institute and Department of Entomology and Nematology, University of Florida, Gainesville, FL 32610, USA.

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http://dx.doi.org/10.1016/j.pestbp.2018.02.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6277143PMC
October 2018
3 Reads
2.014 Impact Factor

Select β- and γ-branched 1-alkylpyrazol-4-yl methylcarbamates exhibit high selectivity for inhibition of Anopheles gambiae versus human acetylcholinesterase

https://doi.org/10.1016/j.pestbp.2018.02.003

Pesticide Biochemistry and Physiology

The widespread emergence of pyrethroid-resistant Anopheles gambiae has intensified the need to find new contact mosquitocides for indoor residual spraying and insecticide treated nets. With the goal of developing new species-selective and resistance-breaking acetylcholinesterase (AChE)-inhibiting mosquitocides, in this report we revisit the effects of carbamate substitution on aryl carbamates, and variation of the 1-alkyl group on pyrazol-4-yl methylcarbamates. Compared to aryl methylcarbamates, aryl dimethylcarbamates were found to have lower selectivity for An. gambiae AChE (AgAChE) over human AChE (hAChE), but improved tarsal contact toxicity to G3 strain An. gambiae. Molecular modeling studies suggest the lower species-selectivity of the aryl dimethylcarbamates can be attributed to a less flexible acyl pocket in AgAChE relative to hAChE. The improved tarsal contact toxicity of the aryl dimethylcarbamates relative to the corresponding methylcarbamates is attributed to a range of complementary phenomena. With respect to the pyrazol-4-yl methylcarbamates, the previously observed low An. gambiae-selectivity of compounds bearing α-branched 1-alkyl groups was improved by employing β- and γ-branched 1-alkyl groups. Compounds 22a (cyclopentylmethyl), 21a (cyclobutylmethyl), and 26a (3-methylbutyl) offer 250-fold, 120-fold, and 96-fold selectivity, respectively, for inhibition of AgAChE vs. hAChE. Molecular modeling studies suggests the high species-selectivity of these compounds can be attributed to the greater mobility of the W84 sidechain in the choline-binding site of AgAChE, compared to that of W86 in hAChE. Compound 26a has reasonable contact toxicity to G3 strain An. gambiae (LC50 = 269 μg/mL) and low cross-resistance to Akron strain (LC50 = 948 μg/mL), which bears the G119S resistance mutation.

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February 2018
13 Reads

Spatial panorama of malaria prevalence in Africa under climate change and interventions scenarios.

Int J Health Geogr 2018 01 16;17(1). Epub 2018 Jan 16.

Human Health Division, International Center of Insect Physiology and Ecology, P.O. Box 30772-00100, Nairobi, Kenya.

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http://dx.doi.org/10.1186/s12942-018-0122-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5771136PMC
January 2018
19 Reads

Containment Studies of Transgenic Mosquitoes in Disease Endemic Countries: The Broad Concept of Facilities Readiness

Vector Borne Zoonotic Dis. 2018 Jan 1; 18(1): 14–20.

Vector Borne and Zoonotic Diseases

Genetic strategies for large scale pest or vector control using modified insects are not yet operational in Africa, and currently rely on import of the modified strains to begin preliminary, contained studies. Early involvement of research teams from participating countries is crucial to evaluate candidate field interventions. Following the recommended phased approach for novel strategies, evaluation should begin with studies in containment facilities. Experiences to prepare facilities and build international teams for research on transgenic mosquitoes revealed some important organizing themes underlying the concept of “facilities readiness,” or the point at which studies in containment may proceed, in sub-Saharan African settings. First, “compliance” for research with novel or non-native living organisms was defined as the fulfillment of all legislative and regulatory requirements. This is not limited to regulations regarding use of transgenic organisms. Second, the concept of “colony utility” was related to the characteristics of laboratory colonies being produced so that results of studies may be validated across time, sites, and strains or technologies; so that the appropriate candidate strains are moved forward toward field studies. Third, the importance of achieving “defensible science” was recognized, including that study conclusions can be traced back to evidence, covering the concerns of various stakeholders over the long term. This, combined with good stewardship of resources and appropriate funding, covers a diverse set of criteria for declaring when “facilities readiness” has been attained. It is proposed that, despite the additional demands on time and resources, only with the balance of and rigorous achievement of each of these organizing themes can collaborative research into novel strategies in vector or pest control reliably progress past initial containment studies.

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January 2018
9 Reads

Green tea proanthocyanidins cause impairment of hormone-regulated larval development and reproductive fitness via repression of juvenile hormone acid methyltransferase, insulin-like peptide and cytochrome P450 genes in Anopheles gambiae sensu stricto

PLOS ONE

Successful optimization of plant-derived compounds into control of nuisance insects would benefit from scientifically validated targets. However, the close association between the genotypic responses and physiological toxicity effects mediated by these compounds remains underexplored. In this study, we evaluated the sublethal dose effects of proanthocyanidins (PAs) sourced from green tea (Camellia sinensis) on life history traits of Anopheles gambiae (sensu stricto) mosquitoes with an aim to unravel the probable molecular targets. Based on the induced phenotypic effects, genes selected for study targeted juvenile hormone (JH) biosynthesis, signal transduction, oxidative stress response and xenobiotic detoxification in addition to vitellogenesis in females. Our findings suggest that chronic exposure of larval stages (L3/L4) to sublethal dose of 5 ppm dramatically extended larval developmental period for up to 12 days, slowed down pupation rates, induced abnormal larval-pupal intermediates and caused 100% inhibition of adult emergence. Further, females exhibited significant interference of fecundity and egg hatchability relative to controls (p < 0.001). Using reverse transcription quantitative polymerase chain reaction (RT-qPCR), our findings show that PA-treated larvae exhibited significant repression of AgamJHAMT (p < 0.001), AgamILP1 (p < 0.001) and AgamCYP6M2 (p < 0.001) with up-regulation of Hsp70 (p < 0.001). Females exposed as larvae demonstrated down-regulation of AgamVg (p = 0.03), AgamILP1 (p = 0.009), AgamCYP6M2 (p = 0.05) and AgamJHAMT (p = 0.02). Our findings support that C. sinensis proanthocyanidins affect important vectorial capacity components such as mosquito survival rates and reproductive fitness thus could be potentially used for controlling populations of malaria vectors.

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August 2017
11 Reads

Bivalent Carbamates as Novel Control Agents of the Malaria Mosquito, Anopheles gambiae.

Chimia (Aarau) 2016 Oct;70(10):704-708

Department of Entomology and Nematology Emerging Pathogens Institute University of Florida, Gainesville, FL 32610, USA.

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http://dx.doi.org/10.2533/chimia.2016.704DOI Listing
October 2016
20 Reads
1 Citation
1.350 Impact Factor

Potential of Camellia sinensis proanthocyanidins-rich fraction for controlling malaria mosquito populations through disruption of larval development.

Parasit Vectors 2016 Sep 22;9(1):512. Epub 2016 Sep 22.

Present Address: Fritz Lipmann Institute (FLI) - Leibniz Institute for Age Research, D-07745, Jena, Germany.

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http://parasitesandvectors.biomedcentral.com/articles/10.118
Publisher Site
http://dx.doi.org/10.1186/s13071-016-1789-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5034625PMC
September 2016
41 Reads
3.430 Impact Factor

Carbamate and pyrethroid resistance in the akron strain of Anopheles gambiae.

Pestic Biochem Physiol 2015 Jun 9;121:116-21. Epub 2015 Mar 9.

Emerging Pathogens Institute, Department of Entomology and Nematology, University of Florida, Gainesville, FL 32610, USA. Electronic address:

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http://dx.doi.org/10.1016/j.pestbp.2015.03.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4457939PMC
June 2015
16 Reads
2.014 Impact Factor

Neurotoxicology of bis(n)-tacrines on Blattella germanica and Drosophila melanogaster acetylcholinesterase.

Arch Insect Biochem Physiol 2013 Aug 5;83(4):180-94. Epub 2013 Jun 5.

Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA.

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http://dx.doi.org/10.1002/arch.21104DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4739519PMC
August 2013
32 Reads
1.021 Impact Factor

Top co-authors

Paul R Carlier
Paul R Carlier

The Hong Kong Polytechnic University

9
Dawn M Wong
Dawn M Wong

Weizmann Institute of Science

9
Jeffrey R Bloomquist
Jeffrey R Bloomquist

Virginia Polytechnic Institute and State University

9
Jianyong Li
Jianyong Li

The First Affiliated Hospital of Nanjing Medical University

7
Rafique Islam
Rafique Islam

University of Michigan

5
Maxim M Totrov
Maxim M Totrov

Virginia Polytechnic Institute and State University

5
Troy D Anderson
Troy D Anderson

Kansas State University

4
Fan Tong
Fan Tong

Emerging Pathogens Institute

4
Polo C-H Lam
Polo C-H Lam

Mayo Clinic

4
Astha Verma
Astha Verma

Department of Chemistry

3