Jul

18

Engineering Magnetic Algae

July 18, 2012 | 2 Comments

Last year researchers at Los Alamos National Laboratory (LANL) took a gene that is known to form magnetic nanoparticles in magnetotactic bacteria and expressed it in green algae, where a permanent magnet can be used to separate the transformed algae from a solution.

Magnetic Algae at LANL. Click image for more info.

That tasks facing algae production for fuels are: keeping algal production over a long time period at healthy rates by ensuring that the selected strain can out compete predators and competitors and second, by finding the lowest-cost path to getting the water out of the algae or the algae out of the water.

The magnetism idea starts with the appearance of an unusual bacterium back in the last days of the dinosaurs that are among the organisms that eventually formed the White Cliffs of Dover.  The northern downs of England are home to the oldest known magnetotactic bacteria, which is to say bacteria that respond to electromagnetic forces.

The bacterium was first observed in the 1960s, and the interest spiked when LANL researchers genetically engineered “magnetic” algae to investigate alternative, more efficient harvesting and lipid extraction methods for biofuels.

LANL isn’t first at attempting to harness the powers of the electromagnetic force in the service of biofuels. Two years before a Siemens researcher, Manfred Ruehrig proved, at lab scale, that it was possible to add magnetic iron oxides into water, encourage the algae to consume it and then use external permanent magnets to separate the suddenly-magnetic algae from the water presenting a low-cost means of concentrating algae out of the volume of water that it grows in.

The next year a team of researchers led by Wankei Wan, at the University of Western Ontario, reported that they had successfully used the introduction of electromagnetic fields to speed up the reproduction rate of a single-celled alga, Chlorella kessleri, in a small-scale raceway pond.

Today, as Tony Haymet, Director of Scripps Institution of Oceanography, Vice Chancellor for Marine Sciences, and Dean of the Graduate School of Marine Sciences at UCSD, put it recently, the science of algae in open pond systems has proceeded to the point where 25 grams per square meter per day of biomass, with a 25 percent lipid content, is no longer a stretch goal for algal scientists. In fact, he said, it has become the table stakes.

For the rest of us that means around 2700 gallons of renewable oil per acre of production. Compared to around 1,000 gallons of ethanol per acre for sugarcane and around 500 gallons per acre of ethanol for corn. Not to mention the far higher BTUs, or heating value of algal oils, gallon for gallon, compared to ethanol.

It appears that the algae production threshold has been crossed, leaving the major issues of sustainability and the overall system costs.

Right now Sapphire Energy and Aurora Algae have developed the most towards large-scale open pond algal systems that they believe have a reliable degree of sustainability. In other words, these firms have engineered up sufficiently in their defense against the natural environment that they can defend their ponds and their prized algae against all the growth problems.

That leaves getting the algae out of the water or the water out of the algae.  Lots of efforts pursue lots of ideas – which brings us back to the magnetism.

Diamagnetic Levitating Frog at Radboud University

Magnetism is a powerful force that can act across large distances. In fact, there is a subclass of research known as diamagnetic that describes a repelling force where material can be successfully floated in a magnetic field, without consuming power. Back in 2006, a group of researchers at Radboud University in the Netherlands managed to successfully levitate a live frog in a magnetic field.  And there is paramagnetism, which describes the attractive force.

There is a lot of work to be done to get the concepts out of the lab and into the field. Yet the research and concept progress shows why many thoughtful people are betting that advances in biology and genetic engineering will cause bio-based materials and fuels to be produced more cost-effectively than from fossil-based molecules.

LANL is looking through algae and helping them to acquire traits that make them spectacularly successful as a platform for fuels and materials.  It’s steps on the way of assembling traits – like magnetism of magnetotactic bacteria and the lipid production rates of green algae – into aggregated groups that we might refer to not only as organisms, but also as organisms with talents.

We can expect more good news on this front in the coming months.  Hat tip to Jim Lane at Biofuelsdigest.


Comments

2 Comments so far

  1. Steve Symes on July 20, 2012 5:09 AM

    The concept of this seems to be brilliant, but how safe is it to modify organisms in this way? Thanks.

  2. AlgaeObserver on July 22, 2012 2:15 PM

    I love the idea! But genetically modified algae will have no chance in Europe due to strict regulations…

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