Thursday, April 3, 2008

Mycorenewal and Ecology


Our mycelium is growing vigorously in the lab. It has been acclimated to metabolizing oil and seems healthy and strong. This is good news of course, but ours is a question of ecological engineering as well as laboratory wizardry. Even though our pet organism is doing well in the Petri dish, this has no bearing whatsoever on how well it does in the field. There is a big difference between life in the Petri dish and the Amazon. So will our oysters become food for insects or out competed by other weedy fungi? We don’t know. However, Pleurotus (oyster) mushrooms happen to be among nature’s most aggressive fungal species, metabolizing everything from wood to coffee grounds to, well, oil. Their enzymes have shown to experimentally breakdown Polychlorinated biphenyls (PCBs) and somehow all fungi have to find a way to compete in a hazardous environment when the vast majority of their biomass consists of threadlike appendages only one-cell thick. So how do they do it?

The long answer is an adventure into complexity or in other words, ecology. The short answer is we don’t know. Well, not exactly. Soil is alive. It is chalk full of critters large and to be sure, small. Really small. Bacteria, lots of bacteria, fungi, spiders, mites, beetles, nematodes, plants small mammals and reptiles all vie for carbon and nutrients in every cubic meter of soil. So why would fungi ever be able to build their vast networks under our feet if they are constantly hectored by hungry, exponentially growing bacteria along every centimeter of their hyphae? The answer of course is, we don’t know, not really.

However, we do have some ideas. Symbiosis is quite frequent throughout nature. In fact, it is happening in every cell of every creature on the face of the planet that has a nucleus. It happens to be most common across Kingdoms, that is organisms that are vastly different from one and other in form and, importantly, metabolism. So some scientists theorize the that fungi form symbiotic relationships with specific, friendly bacteria that keep other, unfriendly bacteria at bay. Unfortunately, the Law of the Jungle in the jungle is somewhat erroneous. Tooth and claw have their role to play in every ecosystem, but cooperation and mutualisms are far to common to ignore.

Plant-fungal symbiosis is as ubiquitous as it is ancient. For over 400 million years—since plants first colonized land—some 90% of all plants have formed fungal partnerships inside or around their roots. Plants gain access to difficult to reach water and nutrients sources and protection from disease while the fungi, called mycorrhizae (“root-fungus”) receives sugar manufactured by the plant. It is possible that different species of fungi form mutualistic relationships with bacteria where select species of beneficial bacteria are encouraged to grow in the area surrounding the mycelium, providing protection in exchange for some nutrient currency. An arrangement such as this is not hard to imagine, in fact, it seems we humans have a similar arrangement in via our appendix: recent findings have identified the appendix as a bacterial safe-haven for beneficial bacteria that help keep pathogenic bugs at bay.

While the ecology of symbiosis can help clarify the niche of fungi in the environment, we need a different take on ecology to see why we are confident that our oysters will have a decent chance of thriving in their new home. All living things are capable of bearing offspring at a rate that far outpaces mere replacement. Usually what keeps any one organism from taking over the world with offspring in a few generations are predators, diseases, famine, suitable habitat and natural catastrophe of all scale. We are designing our project to give our acclimated oyster mushrooms a leg up by taking advantage of what is known as an ecological desert created by the petroleum contamination. The areas are toxic by definition because no other organism in any significant numbers likes to munch on oil. Therefore, we would expect a life form specifically trained (not, to be clear, genetically engineered) to enjoy such a meal would have a distinct advantage in such an environment and reproduce prolifically.

Creating an ecological advantage for our mushrooms will require more than just sowing it over a lagoon of oil. While the oil-digesting capabilities of oyster mushrooms may be a part of the new technology of mycoremediation, the specific process of its application to an affected area is what will ultimately allow it to succeed with as little input and maintenance as possible. This is important because the area contaminated in the Ecuadorian Amazon is so vast and heterogeneous that our techniques will likely have to be site-specific. We will be back in Lago Agrio by mid-April to begin our new round of trials. It is our hope that our latest experiment should provide a baseline methodology that will serve as a template for other Amazonian sites blighted by ill-disposed petroleum waste.

The Amazon Mycorenewal Project is currently looking for additional NGO partners with complementary missions to help support our work here in Ecuador. Interested organizational representatives should contact me at brianapace@gmail.com for more information about our mission and work. Also, Amazon Mycorenewal Project has a new website:

www.amazonmycorenewal.org

and

www.kallambas.org



mycorrhizae photo from: www.helsinki.fi/bioscience/myco/