Christina is our own Defender of the Deep

Dr Christina Roggatz is an interdisciplinary researcher who combines chemical analytical and computational methods with biological observations. Her work focuses on the hidden impacts of climate change, analysing the chemical effects of ocean acidification on key molecules. Christina wants to understand the impacts of pH and temperature on molecules and how they affect the molecules’ functioning in mediating interactions of marine organisms.

Ocean acidification, also dubbed the evil twin of climate change, is an invisible effect by which carbon dioxide reacts with water to form carbonic acid and makes the oceans more acidic. With many crucial interactions between marine organisms being mediated through chemicals, e.g. their sense of ‘smell’, chemical changes to the environment due to ocean acidification have the potential to cause significant disruption. It can affect key processes and interactions within ecosystems and impair marine animals’ ability to find food, mates and ideal living conditions and to avoid predators.

The video below explains this process in more detail.

Working closely with colleagues from Biology and Chemistry at the University of Hull, Christina showed for the first time that even the presumably small pH changes associated with ocean acidification have the potential to change molecules mimicking those used by shore crabs during brood care and by oyster and barnacle larvae during settlement. The findings, published in Global Change Biology, not only reveal substantial impacts on the structure, charge and shape of the molecules, but also an associated loss of their functionality for the crabs.

Christina also found similar impacts on molecules signalling food to fish, published in Frontiers in Physiology. She established with collaborators at the CCMAR (Portugal) - that the molecular changes, amongst other effects, contribute significantly to reduced ability of fish to detect smell and hence food in future ocean conditions.

Besides these clearly negative impacts on some marine animals, Christina’s research also uncovered that some molecules will become more abundant and function more effectively. Two of these molecules are amongst the most potent biotoxins in our oceans: tetrodotoxin, also known as the pufferfish toxin, and saxitoxin, which is produced during harmful algae blooms. Published in Nature Climate Change in close collaboration with experts from the University of Hull and the US, her study revealed that acidified and warmer conditions in future oceans increase the amount of the toxic form of the molecules by up to 30%. This might be good news for the pufferfish who use tetrodotoxin as their chemical defence, but less positive for those animals and humans in regions affected by harmful algae blooms.

Christina is a Research Fellow in Marine Chemical Ecology at the Energy and Environment Institute, Associate Fellow of the Higher Education Academy, and a member of both the Royal Society of Chemistry and the International Society of Chemical Ecology.