Opportunities for biotech await in the Amazon rainforest
The Amazon rainforest is one of the most biologically diverse regions in the world. In addition to combating climate change, protecting Indigenous people and preserving areas of unparalleled natural beauty, rainforest conservation plays a crucial role in discovering new pharmaceuticals.
The natural world provides and inspires countless medications. For example, ergotamine combines caffeine with a fungus called ergot to treat migraines. The precursor for aspirin comes from willow bark and a synthetic form of cone snail venom treats severe pain.
As deforestation continues in the Amazon rainforest, humanity could permanently lose an untold number of life-changing drugs. Biotechnologists are racing to sample, catalogue and test as many compounds as possible before it’s too late. AI software is helping them characterise the molecular components of tropical organisms and develop new medications at breakneck speed.
Rainforest plants may offer the most opportunities for biotech in the Amazon. One study examining 2253 Amazon tree species found 44% of them had beneficial medicinal properties. This finding isn’t surprising given that so many medicines have already come from Amazonian plants.
The cinchona tree bears pink, disproportionately small flowers on its towering frame. It also produces quinine, the first antimalarial drug ever discovered. The class of chemical compounds to which quinine belongs is called the cinchona alkaloids. Using quinine to treat malaria was the first known use of a chemical to treat an infectious illness.
Before the invention of novocaine, people used cocaine — derived from the leaves of the coca plant — as an anaesthetic for hundreds of years, if not longer. The leaves produce a numbing effect that allowed for simple procedures like tooth extractions and giving stitches.
The Chondrodendron tomentosum plant produces tubocurarine, a potent toxin used to create poisoned arrows. In the mid-1900s, doctors also used tubocurarine with anaesthesia to induce muscle relaxation so patients wouldn’t move. Although safer alternatives are available today, it was a valuable compound at the dawn of modern medicine.
These are just a few examples of the countless drugs derived from Amazonian plants. Even when plants themselves don’t produce a useful compound, they often have chemicals that inspire more potent synthetic drugs. They also serve as testing agents and research aids for understanding biological processes.
Over 70% of the world’s plant and animal species live in forests. The Amazon is home to unique wildlife that contains potent compounds that scientists can use to synthesise new drugs.
Scientists think venom-derived peptides could treat rheumatoid arthritis, myotonic dystrophy, multiple sclerosis and more. Several medications made from venom are already available.
Gila monster saliva contains a compound that treats type 2 diabetes. The synthetic eptifibatide — modelled after southern pygmy rattlesnake venom — prevents blood clots during a heart attack or angioplasty. Batroxobin — isolated from South American pit vipers — treats patients with thrombosis.
The jararaca — a type of Brazilian pit viper — produces peptides that treat hypertension and some types of heart failure. Researchers modelled the medication captopril after this mechanism, making it the first medication derived from venom. It inhibits angiotensin-converting enzymes to lower blood pressure. After its creation, scientists synthesised many analogues using the same model, including lisinopril, enalapril, ramipril and perindopril.
Saliva from blood-feeders
Another class of animals that looks promising for medicine is blood-feeding invertebrates like leeches, mosquitoes, horseflies and ticks. These animals often inject bioactive compounds into their host to numb the skin and prevent blood clots. Scientists think the proteins in insect saliva could become anticoagulants, vasodilators, vasoconstrictors, anaesthetics, sodium channel blockers, antihistamines and more.
Thanks to improvements in biotech, scientists no longer have to exploit animals to extract these valuable compounds. That’s good for technicians and wildlife alike.
Milking snakes for their venom is laborious and dangerous, and it requires removing the animals from their habitat. Getting spider or scorpion venom is even more tedious because of the invertebrates’ small size. And — it goes without saying — keeping a tank of mosquitoes or ticks in the lab is a recipe for disaster.
By studying chemical ingredients on a molecular scale, all it takes is a DNA sequence to create the blueprints for new drugs. Researchers can use software to search databases and find peptides with specific properties.
Scientists are racing the clock to sequence animals’ genomes before they go extinct. Most biologists believe there are still numerous undiscovered animal species in the Amazon and even the currently known species haven’t all had their DNA sampled and sequenced. Time is running out to accomplish this monumental task.
Fungi and bacteria
The biotech field includes more than just medicine. In one study, researchers found seven genera of Amazonian fungi with larvicidal activity against Aedes aegypti, one of the most significant malaria vectors. Eight of the fungal culture medium extracts killed over 90% of the mosquito larvae within three days. This finding offers hope for a new form of pesticide.
Of course, many fungi are also well-known for their medicinal properties. Several types of antibiotics, anticancer drugs, immunosuppressants, headache medications and even treatments for depression come from moulds and mushrooms.
The loss of plant species often means fungi are lost simultaneously. Endophytic fungi — which live inside plants for at least part of their life cycle without harming the host — could be an important source of bioactive substances in the Amazon. Endophytes also include bacteria.
So far, scientists have yet to find a plant species that doesn’t host endophytes, meaning the Amazon may be an even richer source of new compounds than it seems at first glance. In some cases, medicinally inert plants might host significant bacteria or fungi with curative properties.
A global treasure
The Amazon isn’t just important to the people who live there. Its stunning biodiversity offers a wealth of chemical compounds, many of which have become medicines or inspired pharmaceutical designs.
Protecting the Amazon rainforest is crucial for mitigating climate change and preserving animal habitats, but it’s also important from an economic and medical standpoint. Who knows what untold drug therapies still lie hidden in its depths? The world will never know unless people take action.
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