These cyanobacteria change color to match ocean light

(Credit: Davide/Flickr)

A species of cyanobacteria has the chameleon-like power to match different colored light across the world’s seas, research shows.

The researchers have shown that Synechococcus cyanobacteria—which use light to capture carbon dioxide from the air and produce energy for the marine food chain—contain specific genes which alters their pigmentation depending on the type of light in which they float. This allows them to adapt and thrive in any part of the world’s oceans.

“Blue light is most prevalent in the open oceans, as it penetrates into deep waters—whereas in warm equatorial and coastal waters there is more green light, and in estuaries the light is often red,” explains David Scanlan, professor in marine microbiology in the University of Warwick’s School of Life Sciences.

“Finding Synechococcus cells capable of dynamically changing their pigment content in accordance with the ambient light color—abundant in ocean ecosystems, making them planktonic ‘chameleons’—gives us a much deeper understanding of those processes essential to keep the ocean ‘engine’ running.

“This will help improve how we look after our waters—and will allow us to better predict how oceans will react in the future to a changing climate with increasing levels of carbon dioxide in the atmosphere.”

cyanobacteria grown in culture
Various pigment types of Synechococcus cyanobacteria from across the world’s oceans, grown in culture. (Credit: U. Warwick)

The researchers made their discovery using data from the Tara Oceans expedition, which took seawater samples from ocean waters all over the world.

From this data, Scanlan and colleagues analyzed specific gene sequences from Synechococcus in the different samples, identifying particular “chromatic adaptor” genes in bacteria living thousands of miles apart.

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This discovery represents a major breakthrough in our understanding of these organisms, which are key primary producers and potentially excellent bio-indicators of climate change.

The French National Centre for Scientific Research and the French Alternative Energies and Atomic Energy Commission led the work, which appears in the Proceedings of the National Academy of Sciences.

Source: University of Warwick