Global Cooling Breakthrough: Scientists Discover Ocean Algae’s Crucial Climate Impact

A common type of ocean algae plays a significant role in producing a massively abundant compound that helps cool the Earth’s climate, new research has discovered.

Researchers have identified Pelagophyceae algae as significant producers of DMSP, a compound crucial for climate regulation. This discovery suggests higher than expected levels of DMSP and its byproduct DMS, impacting global climate cooling. The research highlights the need for further studies on these algae and the enzymes involved in DMSP synthesis.

New Discovery Reveals Unexpected Ocean Algae Help Cool the Earth

Research conducted by the University of East Anglia (UEA) and Ocean University of China (OUC) may revolutionize our understanding of how these tiny marine organisms impact our planet.

The researchers identified the bloom-forming Pelagophyceae algae as potentially abundant and important producers of a compound called dimethylsulfoniopropionate, or DMSP.

Co-lead author Professor Jonathan Todd, of UEA’s School of Biological Sciences, said: “The Pelagophyceae are amongst the most abundant algae on Earth, yet they were not previously known as important producers of DMSP.

“This discovery is exciting because DMSP is an abundant antistress compound, food source for other microorganisms, and major source of climate-cooling gases.”

Dr. Jinyan Wang, OUC/UEA PhD student and first author, said: “Understanding the role of Pelagophyceae in DMSP production means we need to rethink how much of this compound is being produced and how it impacts our climate.”

Impact of DMSP on Climate Regulation

Every year, billions of tonnes of DMSP are produced in the Earth’s oceans by marine microorganisms, helping them to survive by protecting against various stresses like changes in salinity, cold, high pressure, and oxidative stress.

Importantly, DMSP is the main source of a climate active gas called dimethylsulfide (DMS), which is known as the smell of the seaside.

Implications for Global Climate

This study suggests that DMSP production, and consequently DMS release, is likely higher than previously predicted and emphasizes the key role of microbes in regulating global climate.

DMS also acts as a signaling molecule, guiding marine organisms to their food and deterring predators.
When DMS is released into the atmosphere, DMS oxidation products help form clouds that reflect sunlight away from the Earth, effectively cooling the planet.

This natural process is essential for regulating the Earth’s climate and is also hugely important for the global sulfur cycle, representing the main route by which sulfur from the oceans is returned to land.

Discovery of Key Enzymes in DMSP Production

UEA and OUC established the Sino-UK Joint Research Centre to promote cutting-edge research and teaching in marine and ocean science.

UEA’s Dr. Andrew Curson was a key member of the team that identified the novel enzymes responsible for the synthesis of DMSP in diverse bacteria, photosynthetic cyanobacteria and algae.

Dr. Curson said: “The identity of these enzymes allowed our team to identify Pelagophyceae as potentially abundant and important DMSP producers.”

Co-lead author Professor Xiao-Hua Zhang, of OUC’s College of Marine Life Science, said: “By identifying the enzymes involved in DMSP production, scientists can better understand and predict the behavior of these ecosystem-disruptive, brown-tide-forming algae and their impact on global climate change.

“This study has also raised questions about other unidentified versions of the enzymes needed to make DMSP, or entirely different pathways for making it that are currently unknown.”

Future Directions in Marine Biology Research

The researchers say further study of Pelagophyceae algae in their natural environment is needed, as well as more detailed studies on other marine organisms.

Better measurements of environmental DMSP levels, production and breakdown rates, and the abundance of the enzymes involved in making DMSP are also critical to further advance the field.

Reference: “Alternative dimethylsulfoniopropionate biosynthesis enzymes in diverse and abundant microorganisms” by Jinyan Wang, Andrew R. J. Curson, Shun Zhou, Ornella Carrión, Ji Liu, Ana R. Vieira, Keanu S. Walsham, Serena Monaco, Chun-Yang Li, Qing-Yu Dong, Yu Wang, Peter Paolo L. Rivera, Xiao-Di Wang, Min Zhang, Libby Hanwell, Matthew Wallace, Xiao-Yu Zhu, Pedro N. Leão, David J. Lea-Smith, Yu-Zhong Zhang, Xiao-Hua Zhang and Jonathan D. Todd, 11 June 2024, Nature Microbiology.
DOI: 10.1038/s41564-024-01715-9

The research was a collaboration between UEA and OUC, with contributions from Qingdao Agricultural University, the University of Porto, Shandong University and the Laoshan Laboratory in Qingdao, China.

The work was funded by the UK Biotechnology and Biological Sciences Research Council (BBSRC), the BBSRC Norwich Research Park Doctoral Training Partnership program, the UK Natural Environment Research Council, the Leverhulme Trust, the National Natural Science Foundation of China, the Marine S&T Fund of Shandong Province for Laoshan Laboratory, the Chinese Scholarship Council, the Fundamental Research Funds for the Central Universities, the European Union’s Horizon 2020 research and innovation program and the Fundação para a Ciência e a Tecnologia, Portugal.