Biosustainability – BioQuakes

Human use of fossil fuel as a form of energy to sustain industry and modern lifestyle has had a detrimental effect on environmental efficiency. Nature’s ecosystems are dying and the atmosphere is polluted, causing climate change that further negatively impacts the ecosystems. With fossil fuel sources being depleted, humans must find new energy sources to sustain their current way of living while minimizing the potential harmful effects on the environment. Perhaps, surprisingly, a solution to these problems may be found in the untapped power of plants to sustain themselves through use of sunlight and water in a process called photosynthesis.

Photosynthesis is the process by which photons of light (coming from the rays of the sun) and water molecules are converted, through a complex, multi-step process, into glucose, a form of stored energy. Today, scientists are working on various ways to mimic the natural process of photosynthesis through artificial photosynthesis. Their goal is to find clean, affordable, efficient and sustainable ways to create energy that would allow humans to subsist as they do.

Harnessing the power of the sun is full of potential because the sun’s energy is so great that the amount of sunlight hitting the earth in one hour can satisfy the energy needs of all humans for one year.

Currently, the process most similar to artificial photosynthesis is photovoltaic technology which allows a solar cell to convert the sun’s energy into electricity. A small PV cell usually produces between 1 and 2 watts of power when sandwiched between protective materials like glass and plastics. In order to harness maximum energy, these PV cells, which are composed of semiconductor materials, are often chained into arrays that have the capacity to be bound to a larger electrical grid. However, this process is inefficient because it harnesses only 20% of the sun’s energy, in part because the semiconductors in solar panels have limited ability to absorb and store sunlight energy.

By contrast, photosynthesis can store 60% of sunlight as chemical energy in biomolecules. In her research, Yulia Pukshar, a biophysicist at Purdue University, has been replicating the photosynthesis process by creating an analog that collects sunlight then splits water molecules to create hydrogen. Hydrogen is useful as a fuel to be used in fuel cells or as a fuel to be combined with other fuels (like natural gas) to provide power to homes, cars, electronic devices, etc. Much of Pushkar’s research has focused on determining which combinations of catalysts and photosystem II proteins work best to generate hydrogen from water molecules. She seeks to use chemicals and compounds that are abundant, easily accessible, inexpensive and non-toxic. Artificial photosynthesis is being developed with “nontoxic, easily available elements” which sets it apart from preexisting forms of “clean” energy.

Currently, researchers have determined that the most durable oxygen evolving complexes (the portion of photosystem II that promotes photo-oxidation of water during photosynthesis) are those composed of cobalt-oxide based water oxidation catalysts. The use of such catalysts, that most closely resemble the true catalyst present in photosystem II, is highly costly and impractical when applied at a large scale. What seems to be a breakthrough in man-made, photosynthetic technology is merely in its infancy. If human civilization is to ever make a dent in this environmental crisis, new sources of sustainable energy must be implemented globally.

Ever since I moved to Brookville from New York City, I developed a greater appreciation for the beauty and peacefulness of nature in my surroundings. My understanding of the process of photosynthesis has reinforced my sentiments as I now fully comprehend the value of plants to human life. As my family plants more trees on our property, I recognize that such plantings are helping the environment by absorbing CO2 and providing vital oxygen to the atmosphere. For this reason, among others, I support reforestation initiatives around the world as well as the Forest Program at FA.

CRISPR-Cas9 systems are bacterial immune systems that specifically target genomic sequences that in turn can enable the bacterium to fight off infecting phages. CRISPR stands for “clusters of regularly interspaced short palindromic repeats” and was first demonstrated experimentally by Rodolphe Barrangou and a team of researchers at Danisco. Cas9 is a protein enzyme that is capable of cutting strands of DNA, associated with the specialized stretches of CRISPR DNA.

Diagram of the CRISPR prokaryotic antiviral defense mechanism.

Recently, a blockage to the systems was found by researchers which are essentially anti-CRISPR proteins. Before, research on these proteins had only showed that they can be used to reduce errors in certain genome editing. But now, according to Ruben Vazquez Uribe, Postdoc at the Novo Nordisk Foundation Center for Biosustainability (DTU), “We used a different approach that focused on anti-CRISPR functional activity rather than DNA sequence similarity. This approach enabled us to find anti-CRISPRs in bacteria that can’t necessarily be cultured or infected with phages. And the results are really exciting.” These genes were able to be discovered by DNA from four human faecal samples, two soil samples, one cow faecal sample and one pig faecal sample into a bacterial sample. In doing so, cells with anti-CRISPR genes would become resistant to an antibiotic while those without it would simply die. Further studies found 11 DNA fragments that stood against Cas9 and through this, researchers were ultimately able to identify 4 new anti-CRIPRS that “are present in bacteria found in multiple environments, for instance in bacteria living in insects’ gut, seawater and food,” with each having different traits and properties. “Today, most researchers using CRISPR-Cas9 have difficulties controlling the system and off-target activity. Therefore, anti-CRISPR systems are very important, because you want to be able to turn your system on and off to test the activity. Therefore, these new proteins could become very useful,” says Morten Sommer, Scientific Director and Professor at the Novo Nordisk Foundation Center for Biosustainability (DTU). Only time will tell what new, cool, and exciting discoveries will be made concerning this groundbreaking system! What else have you guys heard? Comment below!

BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: Biosustainability

Harnessing the Power of Photosynthesis for Environmental Gain

New anti-CRISPR Proteins Serving as Impediments to this Miraculous System.

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