The bioaccumulation of halogenated organic compounds (HOCs) in the marine food web provides a direct route for human exposure to several classes of persistent organic pollutants. Natural polybrominated organic compounds such as polybrominated diphenyl ethers, polybrominated dibenzodioxins and polybrominated bipyrroles are collectively proposed to be synthesized by marine organisms such as cyanobacteria and red algae involving unknown metabolic pathways harboring yet to be discovered halogenating enzymes. The goals of this project are to provide a genetic and biochemical foundation for the microbial biosynthesis of HOCs in the marine environment. Our research strategy includes a comprehensive genetic, biochemical, and enzyme structure-based analysis of polybrominated metabolite biosynthesis in two model marine bacterial groups, Pseudoalteromonas and Streptomyces, as well as other HOC producing strains discovered in the course of the research. We will provide a direct interrogation of natural maririe samples enriched in HOCs to identify and characterize the prevalence of these biosynthetic pathways in the marine environment. The proposed work will be undertaken jointly by the laboratories of Allen and Moore at Scripps who have a proven track record of collaboration and joint student mentorship. The success of this Project is based on biochemists, microbiologists, structural biologists and genome scientists working together;thus we have enlisted the help of Moore's long-standing collaborator Prof. Joseph Noel (Salk Institute for Biological Studies, La Jolla) to join the Project through a sub-contract to assist in the protein crystallography of brominating enzymes in order to provide a detailed understanding of the structural basis behind enzymatic bromination. Collectively, this project will deliver new molecular-based insight into organohalogen biosynthesis that will be united with other Center investigations to explore the diversity and ecology of these compounds and their impacts on oceans and human health.

National Institute of Health (NIH)
National Institute of Environmental Health Sciences (NIEHS)
Research Program Projects (P01)
Project #
Application #
Study Section
Special Emphasis Panel (ZES1-LKB-J)
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of California San Diego
La Jolla
United States
Zip Code
Whalen, Kristen E; Kirby, Christopher; Nicholson, Russell M et al. (2018) The chemical cue tetrabromopyrrole induces rapid cellular stress and mortality in phytoplankton. Sci Rep 8:15498
Trego, Marisa L; Hoh, Eunha; Kellar, Nicholas M et al. (2018) Comprehensive Screening Links Halogenated Organic Compounds with Testosterone Levels in Male Delphinus delphis from the Southern California Bight. Environ Sci Technol 52:3101-3109
Titaley, Ivan A; Ogba, O Maduka; Chibwe, Leah et al. (2018) Automating data analysis for two-dimensional gas chromatography/time-of-flight mass spectrometry non-targeted analysis of comparative samples. J Chromatogr A 1541:57-62
Zheng, Jing; McKinnie, Shaun M K; El Gamal, Abrahim et al. (2018) Organohalogens Naturally Biosynthesized in Marine Environments and Produced as Disinfection Byproducts Alter Sarco/Endoplasmic Reticulum Ca2+ Dynamics. Environ Sci Technol 52:5469-5478
Chekan, Jonathan R; Moore, Bradley S (2018) Preparation and Characterization of Tetrabromopyrrole Debrominase From Marine Proteobacteria. Methods Enzymol 605:253-265
Podell, Sheila; Blanton, Jessica M; Neu, Alexander et al. (2018) Pangenomic comparison of globally distributed Poribacteria associated with sponge hosts and marine particles. ISME J :
Brunson, John K; McKinnie, Shaun M K; Chekan, Jonathan R et al. (2018) Biosynthesis of the neurotoxin domoic acid in a bloom-forming diatom. Science 361:1356-1358
Agarwal, Vinayak; Miles, Zachary D; Winter, Jaclyn M et al. (2017) Enzymatic Halogenation and Dehalogenation Reactions: Pervasive and Mechanistically Diverse. Chem Rev 117:5619-5674
Arakawa, Neal; Aluwihare, Lihini I; Simpson, Andre J et al. (2017) Carotenoids are the likely precursor of a significant fraction of marine dissolved organic matter. Sci Adv 3:e1602976
Kumar, Abdhesh; Borgen, Miles; Aluwihare, Lihini I et al. (2017) Ozone-Activated Halogenation of Mono- and Dimethylbipyrrole in Seawater. Environ Sci Technol 51:589-595

Showing the most recent 10 out of 26 publications