[ad#PhycoBiosciences AIM Interview]

Research

Genome suggests why red alga didn’t come ashore

April 2, 2013
AlgaeIndustryMagazine.com

In the foreground, the red alga, Chondrus crispus  © Jonas Collén

In the foreground, the red alga, Chondrus crispus © Jonas Collén

The first red alga genome has recently been sequenced by an international team, coordinated in France by Le Centre National de la Recherche Scientifique (CNRS) and Pierre-and-Marie-Curie University (UPMC) at the Station Biologique de Roscoff, in Brittany. The project notably involved researchers from the French National Sequencing Centre: CEA-Genoscope, the universities of Lille and Rennes, and the Muséum National d’Histoire Naturelle.

The genome of Chondrus crispus, also known by the Breton name ‘pioka,’ turns out to be small and compact for a multicellular organism. It has fewer genes than several other species of unicellular algae, which raises a number of questions about the evolution of red algae. This low number of genes could explain why these organisms never colonized dry land, unlike their green counterparts – from which all terrestrial plants are descended.

These findings open up new perspectives on the natural history of algae and of terrestrial plants. They were published online in the journal PNAS on March 11, 2013.

Chondrus crispus is a multicellular red alga of about 20 cm in length. It is very common on the rocky coasts of the North Atlantic where it plays an essential role as a primary producer in these ecosystems. Certain red algae are now used in the agri-food industry for the thickening properties of the carrageenans from their cell walls. These sulfated polysaccharides correspond to the food additive E-407, which goes into many desserts and other dishes. Beyond industrial applications, this first sequencing of a red alga genome sheds new light on plant evolution as a whole.

A Chondrus crispus red alga ©Jonas Collén

A Chondrus crispus red alga ©Jonas Collén

The Chondrus genome had some surprises for the researchers. With only 9,606 genes and 105 million base pairs, it is very small for a multicellular organism. By comparison, the unicellular green alga Chlamydomonas reinhardtii has 14,516 genes, the multicellular terrestrial plant Arabadopsis thaliana has 27,416. The Chondrus genome is also very compact, with each function generally corresponding to a single gene. Gene families are small, and genes closely spaced.

To explain these surprising characteristics, the researchers proposed the hypothesis that, more than a billion years ago, red algae experienced a massive loss of genetic material as a result of extreme environmental conditions. This dramatic event in their evolutionary history would have had many consequences. One result could be the loss of flagellar genes, still present in most other organisms and responsible for the motility of certain cells (such as the gametes during sexual reproduction in most organisms, including humans).

Had this massive gene loss never occurred, red algae might have extensively colonized the terrestrial environment, in the same way as green algae, which are the ancestors of all land plants. Yet this event – a real evolutionary bottleneck –has denied red algae the plasticity and genetic potential necessary to adapt to life on land.

The sequence of the Chondrus genome opens the archives of more than 1,500 million years of evolutionary history of terrestrial and marine plants. It provides a new basis for the study of red algae biology and is the first step in a program aiming to improve our understanding of the origins of life on Earth, the adaptation of red algae to their environment and the biosynthesis pathways of biomolecules of interest, such as carrageenans. The scientists of the group are also hoping to discover new enzymes of interest for marine biotechnology.

More Like This…

HOME Algae Industry Jobs

Copyright ©2010-2013 AlgaeIndustryMagazine.com. All rights reserved. Permission granted to reprint this article in its entirety. Must include copyright statement and live hyperlinks. Contact editorial@algaeindustrymagazine.com. A.I.M. accepts unsolicited manuscripts for consideration, and takes no responsibility for the validity of claims made in submitted editorial.

From The A.I.M. Archives

— Refresh Page for More Choices
Western Morning News reports that Westcountry scientists in the U.K. are using algae to develop an innovative new method of cleaning up contaminated mine water while harv...
Cyanobacteria, also known as blue-green algae because of their color, have endured for more than 2.5 billion years, providing ample time to adapt to changes in the Earth'...
Tess Riley writes in TheGuardian.com about how spirulina may be able to combat malnutrition in developing countries. Spirulina is one of the oldest life forms on Earth, c...
Kevin Quon writes in Seeking Alpha about the financial plights and pivots of Solazyme, the algae industry’s most high profile recent IPO. In a year that started with a sh...
Researchers Greg O’Neil of Western Washington University and Chris Reddy of Woods Hole Oceanographic Institution (WHOI), have exploited an unusual and untapped class of c...
In a recent study, published in PLOS ONE Journal, the influence of light intensity on the growth and lipid productivity of Nannochloropsis salina was investigated in a fl...
A U.S. Department of Energy (DOE) Biomass Energy Technologies Office (BETO) project, awarded to Cal Poly (California Polytechnic State University) in collaboration with M...
Kevin Valine at the Modesto Bee writes that the California city of Modesto may sell the algae that grows in its roughly 1,000 acres of sewer ponds at its Jennings Road wa...
Solazyme has announced that total revenue for the fourth quarter of 2014 was $14.5 million, compared with $11.3 million in the fourth quarter of 2013, an increase of 29%....
Don Willmott writes in Huffington Post about Nevada-based Algae Systems, which has built a test plant on Alabama's Mobile Bay to not only turn algae into diesel fuel but ...
James Goodman writes in the democratandchronicle.com about Jeffrey Lodge, an associate professor of biological sciences at Rochester Institute of Technology, who knows wh...
As one of the most water-poor countries in the world, Jordan’s current water resources are significantly below the global water scarcity line. Annual rainfall falls under...
K. S. Rajgopal writes in thehindu.com about a new study that demonstrates how macroalgal biomass from Gelidiella acerosa and Gracilaria dura collected from Adri and Verav...
In one of the first studies to examine the potential for using municipal wastewater as a feedstock for algae-based biofuels, Rice University scientists found they could e...
Sami Zaatari writes for the Middle East’s Gulf News that Abu Dhabi’s coastal sabkhas – the Arabic phonetic translation for salt flats – hold great potential for solar pow...