The hypothesis to be tested is that the Deepwater Horizon oil spill in the Gulf of Mexico will, by increasing the presence of oil-associated microbes in the marine environment, induce changes in the normal community of microbes (the microbiome) of fish and other marine organisms. For example, this exposure may result in new symbiotic host-microbe relationships between fish and bacteria. This research project has two aims: (1) To examine the bacteria of the digestive tract of fish from areas exposed to the Gulf oil spill for the presence of oil-associated microbes. A comparison with microbes from fish that have not been exposed to the oil spill will determine if exposure has led to a changed microbial community in oil-exposed fish. (2) To determine if genes related to the metabolic processing of oil (and which occur normally in oil-associated microbes) have been transferred into the normal intestinal bacteria of fish as a consequence of exposure to the Gulf oil spill.
Broader Impacts This project will introduce undergraduate students from minorities traditionally underrepresented in science to biological research, and engage them with a project that is relevant to a problem currently facing society. This research project will also be integrated with lectures and laboratory instruction. Students will be recruited to conduct undergraduate research at all levels of the investigation, from field work to molecular biology to web-based bioinformatics. Students will participate in the analysis of results, and the presentation of their work in posters and talks at scientific conferences, as well as in scientific manuscripts. This project will involve collaboration with the Louisiana Universities Marine Consortium. Results will also be made publically available through the office of Satellite Telecommunications Network Interface/Distance Learning at SUNO and the investigator's website www.sunocas.com/tietzel.
The hypothesis to be tested was that the Deepwater Horizon oil spill in the Gulf of Mexico would, by increasing the presence of oil-associated microbes in the marine environment, induce changes in the normal community of microbes (the microbiome) of fish and other marine organisms. For example, this exposure may result in new symbiotic host-microbe relationship between fish and bacteria. This research project had two aims: (1) To examine the bacteria of the digestive tract of fish from areas exposed to the Gulf oil spill for the presence of oil-associated microbes. A comparison with microbes from fish that have not been exposed to the oil spill would determine if exposure has led to a changed microbial community in oil-exposed fish. (2) To determine if genes related to the metabolic processing of oil (and which occur normally in oil-associated microbes) have been transferred into the normal intestinal bacteria of fish as a consequence of exposure to the Gulf oil spill. Utilizing ships and resources from Louisiana Universities Marine Consortium (LUMCON), in field trips on 9/10/2010, 10/8/2010, 11/12/2010, undergraduate research students and the Principal Investigator captured specimens of the fish of interest, i.e. the Gulf Menhaden, the Atlantic Croaker, and Killifish in the oil spill areas of the Gulf of Mexico near Chauvin, LA. Numbers of Atlantic Croaker (9, 48, 33) were high, however the amount of Gulf Menhaden (65, 0, 3) showed a strong decline in October and November of 2010. Similarly, trawling in the spring of 2013 showed high numbers of Atlantic Croakers (>45) and very few Gulf Menhaden (1). Microbes were isolated from fecal slurry isolated from the digestive tracts of refrigerated and frozen fish. Isolation of DNA of microbes of the fish intestine was most successful with MoBio's Fecal DNA Isolation Kit. Modern techniques of Molecular Biology were used such as Polymerase Chain Reaction (PCR) applications for the detection oil spill microbes such as Alcanivorax borkumensis or their genes such as alkane hydroxylase-1 (alkB1) and alkB2. Experiments testing the sensitivity of the detection method showed that minute amounts of oil spill microbes such as 100 picograms can be detected. Gulf Menhaden fish from the oil spill region tested positive for the alkB2 gene suggesting presence of the oil spill microbe Alcanivorax borkumensis in the digestive tract of fish exposed to the Deepwater Horizon oil spill of 2010. These data support the hypothesis of the project that the anthropogenic oil spill caused changes of the intestinal microbial community of fish that includes the introduction of oil spill microbes. It remains to be seen whether or not oil spill microbe genes themselves transferred to the natural microbes of the fish gut. Broader Impacts This project introduced undergraduate students from minorities traditionally underrepresented in science to biological research, and engaged them with a project that is relevant to a problem currently facing society. Two African American Biology undergraduates at the Historically Black College and University Southern University at New Orleans (SUNO) together with their mentor Dr. Illya Tietzel conducted the research. As these students are living in the Gulf coast region that was impacted by the 2010 Deepwater Horizon oil spill, the students had a great opportunity to use their education in Biological Sciences to study the biological impact of the oil spill close to their home. In 2010, students were recruited and trained to conduct undergraduate research at all levels of the investigation, from field work to molecular biology to web-based bioinformatics. Students participated in the analysis of results, and by presenting their work in posters and talks at scientific conferences. They also secured travel awards. Mr. Kiffin earned the following additional awards: a) poster award at the 55th Annual Wind River Conference for Prokaryotic Biology; b) third place in oral presentations at the 69th Joint Annual Meeting of the National Institute of Science and Beta Kappa Chi. The project involved collaboration with LUMCON. Under the leadership of Dr. N. Rabalais, resources such as boats, boat operators and a trawl net were provided. The University of New Orleans kindly provided some online training and protocol. Results were made publicly available through the investigator's website www.sunocas.com/tietzel/NSF%20Oil%20Spill%20Research.htm . This research project was also integrated with lectures and laboratory instruction to broaden the impact. More than 94% of SUNO’s biology undergraduates belong to the African American minority and attend the General Microbiology lecture (BIOL217) and lab (BIOL217L) as well as the Molecular Biology lecture (BIOL325) and lab (BIOL325L) that the Principal Investigator is teaching. Students learned the microbiological assay of fermentation by using the oil spill microbe and investigating its potential to ferment sugars in BIOL217L. In BIOL325L students learned isolation of microbial DNA by using the oil spill microbe. The students learned to use PCR by detecting the alkB genes of A. borkumensis.
