by Shauna Bennett
Biotechnology aims to apply biological organisms, agents, or materials towards goods and services. This can cover areas such as drug discovery, environmentally friendly products, natural pollution remedies, laboratory research tools, and nature-inspired materials. The area of biotech that focuses on resources from the sea has been named blue biotech, and this industry is proving that there is a lot that the ocean has to offer.
The oceans cover 70% of our planet and contain up to 99% of the biosphere. People often think of the rainforests as a rich treasure trove of biodiversity to explore, but the oceans contain the greatest unexplored biodiversity on earth. And what does this vast biodiversity offer?
Aside from normal environmental pressures like predators and infectious agents, the sea contains great environmental extremes of temperature, pressure, salinity, acidity, etc. Marine organisms have adapted to these conditions to survive, evolving novel physical properties, unique biological pathways, hardy enzymes, and a plethora of chemicals with potential medicinal applications. These biological innovations span organisms from unicellular life like bacteria to stationary corals to swimming jellyfish to large vertebrates like sharks.
When diving into information about blue biotechnology, the most visible enterprise is the search for useful molecules. Many non-motile organisms of the sea have evolved chemical defense mechanisms to protect themselves from predators. These chemicals – biologically synthesized small molecules with activity against another organism – have much potential for use in therapeutics. Because these chemicals are diluted into surrounding water and can be quickly carried away by currents, they are often very potent against their intended target.
Marine sponges provide an interesting number of useful active compounds. Two well-known sponge-derived pharmaceuticals are Ara-A and Ara-C, which came from compounds isolated in the 1950’s. Ara-A, the first antiviral drug, and Ara-C, an anticancer agent, are nucleosides that inhibit DNA synthesis. Besides nucleosides, sponges provide alkaloids, sterols, terpenes, peptides, fatty acids, peroxides, and other molecular forms with biological activity found to be clinically useful.
Diverse bioactive chemicals have been found in corals, marine fungus, ocean dwelling bacteria, exotic tentacled invertebrates and other marine organisms. The diversity of sea life is matched only by the diversity of the molecules they produce.
Environmental extremes lead to adaptations that allow organisms to survive and function in those extremes. These adaptations in enzymes and biological pathways can offer novel tools for industrial or laboratory purposes. A well-known example of such a tool is the thermostable DNA polymerase used in the Polyomerase Chain Reaction so commonly relied on in molecular biology. Vent-DNA polymerase is one variant isolated from an ocean dwelling bacterial species native to submarine thermal vents. This bacterial species can grow in boiling temperatures up to 104°C, where enzymes would normally be denatured. Another example is green fluorescent protein; isolated from jellyfish, its value as a research tool won its discoverers the Nobel Prize in chemistry in 2008.
Jellyfish have provided an invaluable research tool - green fluorescent protein. Image from Flickr.
Environmentally minded products
Bioremediation is the use of organisms to break down and clear pollutants, and the ocean is an important site where solutions might be found. It is estimated that over a million tons of crude oil enter the marine environment each year. Luckily, certain marine microorganisms have evolved the ability to metabolize petroleum hyrocarbons. In particular, marine cyanobacteria have been implicated for crude oil degradation. Additional research has also found that combinations of species tend to work better than single species. With more studies, the future might provide a recipe for a microorganism consortium that can clean up oil spills.
For environmentally minded consumers, seaweed has a lot of potential. It is easier, cheaper, and more ecologically sustainable than fishing and can provide a nutrient-rich food source for a growing population. It can be used as a biostimulant for crops and it absorbs carbon from the atmosphere. Additionally, since seaweed farming doesn’t compete with food production from land agriculture, it could replace corn and sugarcane as a major source of biofuels in the next few years.
Sustainability and environmentally conscientious production techniques are often important to communities like surfers, with their intimate relationship with the sea. Recently, the surfboard company Arctic Foam came together with USCD scientists and the algae-based renewable fuels biotech Solazyme to work on the first algae-based surfboard. Most surfboards are currently produced from unsustainable materials associated with carcinogens and petroleum byproducts, but new algae-based oil can be used instead of petroleum in making polymer foam, an exciting new development for the surfing industry.
Taking advantage of Nature’s innovation
When an engineer runs out of ideas for tackling a problem, nature can sometimes offer clever solutions. Taking advantage of nature’s patterns and structures is known as Biomimicry. Velcro is one of the first examples. Invented in 1941, it was inspired by the way burrs (Burdock seeds) can reversibly attach to hair and clothing. Under a microscope, the burrs display tiny hooks that easily latch on to any material with small loops.
The unique organisms of the ocean have a lot to offer in terms of clever designs. Shark skin has inspired a technology called Sharklet, which is a material pattern that inhibits microbial growth. Scientist Tony Brennan found that sharks do not experience biofouling – the growth of organisms like algae on their skin – and so set out to determine why. The texture of shark skin turns out to have deep microscopic grooves that present an energetically unfavorable surface for growth of microorganisms, and this principle was used to create Sharklet. This new material has been found to not only be useful against algae, but also inhibits growth of bacterial biofilms, making it appealing for use in hospitals and high touch areas.
The Arapaima fish have evolved a physical defense mechanism to survive among their local predators, the piranha. They have scales that are designed like armor, combining a mineralized outer layer with an inner layer of perpendicularly aligned collagen fibers that give them strength and flexibility. The piranha’s razor-sharp teeth cannot fully penetrate these scales. These biomimetic studies can be applied to military body armor and other armor-related applications.
Inspiration has also come from the glue-like mucus that allows barnacles and mollusks to stick to surfaces under water. Its strength makes it very appealing as an adhesive, since scientists have struggled to make similar glue that does not dissolve in water. This natural substance is made up of proteins that self-assemble into a meshwork that gives it its strength. Reproducing the natural protein meshwork in the lab presented a challenge, but researchers at MIT eventually found a way to produce even stronger glue. This substance was made by combining the glue-producing mollusk genes with ocean-dwelling bacterial genes and then expressing them together in biofilm-producing bacteria. The combination has led to production of super-glue that is stickier than anything available, and could prove useful in wet environments like ship hull repair or even wound healing.
The Future is Bright (Blue)
Blue biotech will have a lot to offer in the coming years. For drug discovery, the obstacles faced lie mainly in the methods of collecting samples from deep in the ocean and screening them for activity. For every ten thousand molecules screened, traditionally only one will reach the market. Such a low yield is only profitable if cost-effective high-throughput methods are developed. For now, identification of clinically relevant compounds often relies on the initial collaboration of academia with the biotech industry.
The future of blue biotech may see efforts turn from screening large chemical libraries to evaluating genomic data from marine species, taking advantage of sequencing technologies to predict or manipulate marine biology. It may also see more seaweed farming and innovative materials inspired by ocean dwelling creatures. The next big thing in biotech may still be waiting for discovery under the sea.
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