Medicine, Ocean Science, and Pharmaceuticals

When David Picton first arrived at BIOS in 2013 as a work study intern, he had no intention of pursuing a career in research science, wanting—instead—to become a medical doctor. At 19 he had just finished his first year of studies in biomedical sciences at Newcastle University in the United Kingdom and was simply looking for an opportunity to travel and try his hand at something new, with the hopes of gaining a few skills in the process.

To his surprise, the experience changed his academic and career trajectory. For two months, he worked with physical oceanographer Rod Johnson and the Bermuda Atlantic Time-series Study (BATS) program, assisting with research cruises and processing samples taken throughout the water column. Picton returned a year later, in 2014, to work with Rachel Parsons in the Microbial Ecology Laboratory on a long-term project studying oxygen minimum zones (areas of water characterized by low levels of oxygen). It was under the mentorship of Parsons and Johnson that he felt a career in academic research would be more fitting, as it genuinely intrigued him and gave him a newfound sense of purpose.

“I felt like, before my time at BIOS, I was following sort of a guide as to what my career should look like, but it was never really tailored to me,” Picton said. “The opportunity to work at BIOS led me to really try to understand what interested me and this has helped me channel my energy and commitments.”

He graduated from Newcastle in 2015 with an undergraduate degree in biomedical science with a focus on medical microbiology, followed by a master’s degree in 2016 in microbiology. Now, as a fourth-year doctoral student at Durham University in the United Kingdom, Picton is using molecular biology, biochemistry, and microbiology to investigate the interactions between bacteriophages (viral predators of bacteria) and their bacterial hosts. He credits his earlier work placements at BIOS with giving him a significant advantage when applying for Ph.D. positions.

As part of his doctoral research, which is funded by the Biotechnology and Biological Sciences Research Council—part of the U.K. Research and Innovation program—Picton was required to participate in a 12-week research placement at an organization outside of his research field. During his work with Parsons in 2014, he discovered an increase in the abundance of single-celled marine organisms, similar to bacteria, called Thaumarchaeota, within the water column samples taken at BATS. Seeing the potential for expanding on this work, and looking to use the practical skills in biochemistry that he’d learned since then, Picton arranged to spend July to September of this year working with Parsons on the BIOS-SCOPE project, a five-year investigation that aims to characterize the microbial ecology of the Sargasso Sea.

His work with BIOS-SCOPE focused on the oxygen minimum zone at the BATS site, which is located between 1,300 and 1,600 feet (400 to 800 meters) deep. In this region, the oxygen in the water decreases due to net respiration of marine micro-organisms, such as bacteria and plankton, creating a rapidly changing habitat for marine microbes. This reduction in oxygen provides an ecological niche for organisms that rely on other growth pathways, such as those using ammonia and sulphur instead of oxygen. By looking at the environmental DNA that is isolated from living cells extracted from seawater, Picton can identify which marine microorganisms inhabit the oxygen minimum zone. Beyond that, by isolating RNA (the messenger for DNA) from these samples, he can quantify how active certain metabolic processes are within these microbes.

“Once we identify microbial communities, we can begin to look at their different metabolic processes,” he said. “Different lineages of bacteria and Archaea are responsible for changing the chemical composition of the ocean, and it’s our aim to decipher which lineages are responsible for certain changes.”

Having completed his BIOS-SCOPE internship, Picton returned to Durham University to begin the last phase of his doctoral program, which entails compiling years of data into an organized thesis. While, ideally, he’d like to take a year and travel after he completes his degree, he says it’s most likely that he will look for work within the field of pharmaceutical research, hopefully with a focus on exploring the potential for bacteriophage therapy to treat infections.

Looking back on his own journey, he is keen to share his experiences with others who may be interested in pursuing a doctoral degree. “I meet plenty of students who find themselves regretting their choice to study for a Ph.D. because they never really thought about their motives,” he said. “It’s not a natural progression from a master’s degree and it’s not something you should do purely because you enjoy research. But if you really, really, and I mean really, feel like you want to commit to a topic and make it your own, and if you feel like you want to answer some of the most intricate questions life has to offer, then it’s an incredibly rewarding experience.”