Award: OCE-1634478

Project outcomes Collaborative Research: Do Cyanobacteria Drive Marine Hydrocarbon Biogeochemistry? Christopher M Reddy, Principal Investigator This project successively completed the proposed research to investigate the natural production of pentadecane by the ocean-dwelling bacteria, Prochlorococcus and Synechococcus. Pentadecane is a major component in crude oils and often the most abundant compound in diesel fuels. Prochlorococcus and Synechococcus are some of the largest producers of oxygen in the ocean, which in turn, can be ultimately inhaled by humans. Despite their widespread abundance and global impact, little was known about biological production of pentadecane and how the knowledge gained might be used to respond to oil spills. Hence, this project served a dual benefit to basic science and society. From a basic science perspective, we learned Prochlorococcus and Synechococcus produce huge quantities of pentadecane and another group of bacteria rapidly eat it. The societal relevance was the connection of the latter microbes to those who eat oil after spills The cartoon attached captures what we learned from our collection and analysis of field samples from a 2017 research cruise aboard the R/V Neil Armstrong and laboratory-based studies. Our major findings were: Cyanobacteria produce pentadecane in the upper 600 feet of the ocean. The estimated global flux of cyanobacteria-produced pentadecane was estimated to be equivalent to ~315,000,000 gallons of oil. When compared to the input of oil into the ocean from natural seeps and human-induced releases, cyanobacteria add 100 to 500 times more hydrocarbons each year. Pentadecane is also rapidly eaten by a population of pentadecane-degrading bacteria. Collectively, these results led us to hypothesize that cyanobacterial hydrocarbon production selectively primes the ocean?s microbiome for degradation of naturally seeped oil and human-induced releases. The knowledge gained from this work helped us inform industry and government officials, and provide accessible information to the media, policy makers, and non-governmental organizations (NGOs). We facilitated communication between academic scientists, researchers and regulators at the US EPA and US Coast Guard/NOAA, the government organizations responsible for responding to oil spills on land and in coastal waters, respectively. Establishing these working relationships for cross-exchange are timely and will lead to more effect responses when spills do occur. Specific contributions relevant to society via published opinions, expert advice, and interactions with the media are below: Opinion pieces Reddy, C.M. (2020). Don't assume the worst about the Mauritius oil spill. CNN, posted online August 23. Reddy, C.M. (2020). A dangerous leak of diesel fuel in the Arctic. CNN, posted online June 9 Ward, C.W., Reddy, C.M., Overton, E.B. Why Sunlight matters for marine oil spills (2020) EOS, posted online April 28 Reddy, C.M. (2020). Lessons from Deepwater Horizon for coronavirus. Boston Globe, posted online on March 31 Expert advice: Russian Federation, Siberian oil spill (Summer 2020) Mauritius, MV Wakashio oil spill (Summer 2020) Massachusetts Attorney General, illegal production of home heating fuels (Spring 2020) Brazilian Navy, NOAA, and US State Department, Brazil Mystery spill (2019 to 2021) US Department of Interior, oil leaking from the USS Arizona (2018 to 2020) Media interviews (when cited) "Mauritius oil spill: questions mount over ship fuel safety", Climate Change News, 2/19/21 "Five famous environmental disasters where humans and nature healed together", Popular Science, 2/16/21 "What did we learn from the Deepwater Horizon disaster?" C&EN, 9/13/20 "As if Yemen needed more woes, a decrepit oil tanker threatens disaster", NY Times, 7/17/20 "Scientists discover a new material for cleaning up oil spills", NPR, 7/16/20 "Deepwater Horizon: What we learned from worst oil spill ever" Christian Science Monitor, 6/10/20 "Deepwater Horizon disaster fueled a Gulf science bonanza", WIRED, 4/22/20 "Keystone pipeline spills 9,120 barrels of oil in Dakota Wetlands", EOS, 11/8/19 "Thousands of barrels of oil are contaminating Brazill's pristine coastline", Washington Post, 10/22/19. Last Modified: 06/03/2021 Submitted by: Christopher M Reddy