New thesis with unique insights into the earliest living animals on our planet

2022-02-04

Sponges were likely the earliest living animals on our planet, thus containing important clues about the evolution of humans. In a new thesis, Karin Steffen has as the first researcher ever mapped the genome of Geodia barretti, a complex creature from the deep of the North Atlantic.

Karin Steffen and supervisor Paco Cardenas in the Swedish archipelago

Despite the fact that science has only managed to study a few per cent of all known organisms, nature is our main source of new drugs. Excursions in the plant and animal kingdom have contributed to several groundbreaking discoveries, and now Karin Steffen, PhD student in pharmacognosy, presents unique observations from one of our planet's last unknown outposts in her thesis Genomics and metabolomics in the North Atlantic deep-sea sponge Geodia barretti.

“My studies focus on marine sponges, a fascinating form of organisms that were probably the earliest living creatures on earth. The fact that they early on in evolution deviated genetically from all other animals and have preserved their uniqueness means that they offer several important clues about our evolution, and in my research I have mapped the genome of Geodia barretti, a creation that carries complex bacterial flora and probably important information about the immune system and its development,” says Karin Steffen at Uppsala University.

Conducting research in the deep sea is often both costly and complicated. Diving requires access to boats and crew, but can be canceled at short notice if equipment or weather do not meet the requirements. Due to economic and logistical reasons, marine biological research is often located to shallow waters, but through her involvement in the Horizon2020 project SponGES, Karin Steffen has had access to sponges even from the more inhospitable deeps of the North Atlantic.

Karin Steffen porträtt
Karin Steffen, Faculty of Pharmacy

“The fact that marine sponges get their nutrition from seawater means that they contain lots of different bacteria, which in turn are believed to contribute to the sponge's large production of chemical natural products. A difficult question to answer has been whether individual species of sponges carry identical sets of microbes regardless of sea depth. In my dissertation, I show in comparative studies how sponges that live at depths greater than a thousand meters have individual differences in both genetic material, bacteria and which metabolites they emit.”

The fact that 70 percent of the earth's surface is sea and that the number of pharmacognosists is relatively small creates a difficult equation. Science has so far identified close to ten thousand species of sponges and every year hundreds of new metabolites are discovered that can be vital to drug development. At the same time, climate change and the exploitation of marine environments threaten to eliminate complex ecosystems within the foreseeable future.

“We all know how coral reefs are dying from rising water temperatures, and it is reasonable to assume that sponge reefs are also affected in a corresponding way. The fact that so few voices are raised to protect marine sponges may be because our references don’t reach beyond SpongeBob SquarePants, but sponges are everywhere. Today we don’t have to look further than Fyrisån, but if we do not act soon, there is a great risk that unique sources of new knowledge will be lost forever,” says Karin Steffen.

FACTS

  • Karin Steffen defends her thesis Genomics and metabolomics in the North Atlantic deep-sea sponge Geodia barretti via Zoom (https://uu-se.zoom.us/j/61933938551), Friday 11 February, at 13.15.
  • To date, science has identified more than 160 different fungal species in Swedish waters and more than 300 species in Norwegian waters.
  • Pharmacognosy can be defined as the Study of Pharmaceutical Products that originates in nature.

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CONTACT

Karin Steffen portraitKarin Steffen, PhD Student
Department of Pharmaceutical Biosciences
Karin.Steffen@farmbio.uu.se

text: Magnus Alsne, photo:Uppsala University, Mikael Wallerstedt

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Last modified: 2022-03-31