You are here

Rousel Orozco

Program: Ph.D.

Advisor: Patricia Stock

Research & Interests:

My research has focused on the molecular, phenotypic and phylogenetic description of Photorhabdus sp., the bacterial symbionts of entomopathogenic nematode of the genus Heterorhabditis. One of my main interests is the study of the secondary metabolites produced by these bacteria.  Such molecules are highly active towards both eukaryotes and prokaryotes, and represent an arsenal of compounds that protect the nematode against soil competitors while reproduction occurs inside an insect cadaver. Some of these molecules have also been implicated in nematode bacteria signaling during development and reassociation.  In addition to the application of the nematode-bacteria system for insect control in agricultural settings, I am interested in the potential use of these small molecules as antimicrobial, insecticidal, nematicidal products; as well as their possible use as pharmaceuticals.  As part of my PhD research, I am focusing on the role of Photorhabdus sp. secondary metabolites in nematode-bacteria communication. Specifically, I want to look at nematode transcriptome changes resulting from exposure to the various types of small molecules and non-ribosomal peptides produced by their symbiont. I aim to elucidate nematode genetic pathways related to symbiosis, food signaling and nematode development which are affected by their symbiont secondary metabolites. Since the nematode-bacteria system offers a wonderful model to study cross-kingdom interactions, I hope that by studying such intimate level of communication between a eukaryotic host and the prokaryote symbiont I can contribute to the understanding of the communication between humans and our microbial symbionts and pathogens.

Prior Graduate Degree:
M.S. 2012, University of Arizona



Orozco, R., Hill, T. and Stock. S.P. Characterization, and phylogenetic relationships of Photorhabdus luminescens subsp. sonorensis (-Proteobacteria: Enterobacteriaceae) the bacterial symbiont of the entomopathogenic nematode Heterorhabditis sonorensis (Nematoda: Heterorhabditidae. Current Microbiology 2012, DOI: 10.1007/s00284-012-0220-6.

Xu Y., Orozco R., Kithsiri Wijeratne E.M., Espinosa-Artiles P., Leslie Gunatilaka A.A., Patricia Stock S., Molnar I. (2009) Biosynthesis of the cyclooligomer depsipeptide bassianolide, an insecticidal virulence factor of Beauveria bassiana. Fungal Genetics and Biology 46(5): 353-364.

Xu Y., Orozco R., Wijeratne E.M.K., Gunatilaka A.A.L., Stock S.P., Molnar I. (2008) Biosynthesis of the cyclooligomer depsipeptide beauvericin, a virulence factor of the entomopathogenic fungus Beauveria bassiana. Chemistry and Biology 15(9):898-907.



Last updated 9 Feb 2017