Tuesday, October 16, 2007

Microbe Hunting in Industrial Wastelands

As members of a modern industrial world, we are all acutely aware of the paradox of our daily lives. The questions of how to reconcile the physical actions of our life with the ideological positions we take either politically, morally, or spiritually looms large in many of our minds. When we get in our car to go buy organic veggies at the local co-op we are actively contributing to a litany of deleterious anthropogenic assaults on the environment. How then can we reconcile the great disconnect between our modern lives and our understanding of the environment? Perhaps microbes can offer some assistance.

Some environmental scientists have dedicated them selves professionally to addressing environmental degradation under the aegis of research are striving to harness technological advancements and natural phenomenon to lessen the anthropogenic impacts and, in some rare cases, translate deleterious impacts to positive interaction with the natural world. The dominant focus of environmental research is to lessen negativity rather that transform to actions to positive interactions. A few people are striving for the latter. William McDonough and Micheal Braungart are certainly worthy of mention as they are dedicated to the cause through the optimization of industrial design processes and criteria. Their work has resulted in some very promising shifts in design concepts that have begun to be adopted by companies from clothing, automobile, textile, and packaging manufactures, to municipalities in the design of new communities. At the core of their approach to design is the observation that waste equals food, which is rooted securely in natural phenomenon. In nature all substances are food for some creature no matter how unappealing it may seem. For every substance on this Planet there is a creature that can eat it. Even basic metal elements such as iron are a source of energy for life.

Logically, incorporating the concept of web-like material flows rather than the traditional source to sync trajectory of resource to waste that has universally governed industry has produced some revolutionary results. Results such as a building that makes more energy than it consumes and a textile factory that cleans water, carpets that give nutrition rather than toxicants, packaging that help plants grow when left on the ground, etc.

The web of life (or materials) is a rule that presides over nature without discrimination. As with all life, microbes are inextricably embedded in a tangled hierarchy of organisms. Moreover, every compound no matter how toxic or foreign is food for a microbe. All substances are just intermediate conformational states briefly between parent and progeny; there is no waste.

Examples of environmentally beneficial impacts from scientific activity are rare (some would suggest these two concepts to be mutually exclusive as the technological advancements brought on by science inevitably produce negative effects on the natural systems from which they are derived). In fact, any assistance science has offered nature has been in the form of correcting errors to lessen the impacts of previous scientific “advancements”. This trend was crystallized when the title of “scientist” was adopted during the industrial revolution forever disassociating it’s self from nature, which dominated scientific thought during the times of “natural philosophers”.

Science has a biased for solving the problems of a human nature such as disease, famine, and comfort yet today the separation between the human prosperity and environmental health only exists in the minds of those who actively maintain the egoist view of human supremacy over natural systems. Science has not adjusted for this realignment of consciousness and remains stubbornly entrenched in a for-human-benefit only paradigm. One only needs to leaf through the pages of Nature or Science where articles, advertising, employment announcements and grant offerings to see clearly the domination of for-human-benefit science. It is difficult to find fault in this tendency as the alleviation of human suffering is, and should be a primary concern for scientific endeavor. However, clearly the focal points in this line of inquiry are symptoms of a disease despite the fact that a disease’s origins reside conditions that give rise to the disease, which is often an outcome of the health of the diseased individual’s surroundings or environment. The dominance of studies on mechanisms of carcinogenesis for example, does not address the root cause of many cancers (exposure to mutagenic chemicals) and therefore sidesteps all attempts at a “cure” for this disease. Clearly, addressing the root causes of human disease is the logical aim of most scientific activity, however rather than striving for a cure, science is merely inventing colorful new band-aides.

The paradox of scientific progress giving rise to negative environmental impacts simply, which serve as later subjects of scientific inquiry is perhaps one of the many ways in which, though the evolutionary process, these disconnects are resolved. Sri Aurobindo perhaps states it better in The future evolution of man, “such contradiction is part of Nature’s general method; it is a sign that she is working towards a greater harmony. The reconciliation is achieved by an evolutionary process.”
Applied environmental science is therefore simply dedicated to the preservation of the human species through this evolutionary reconciliation.

One scientific discipline that offers some very promising contributions to a positive human enterprise is in the arena of environmental microbiology. One of the first observations one makes when investigating the world of microbes is that there are many, many, many “bugs” out there. Recent estimates suggest there are on the order of 1016 prokaryotic (bacteria and similar single celled organisms) species, compared to an estimated 1011 stars in our galaxy; there is truly a universe of microbes right under our fingertips. In one gram of soil, for example there are approximately 10,000 different species of single celled microbes.

It is clear that microbial communities are central to the health of a body, a soil, a city, an ecosystem and most of the plant’s geochemical cycles. Without microbes, all life as we know it would not exist (Early cyannobacteria the Earth’s early ocean waters changed the atmosphere of the planet rendering it suitable for terrestrial life). Can microbes help get us out of this mess we’ve gotten our selves into?

Individual microbial species occupy specific, narrowly defined niches. The food source for a microbe is often one type of molecule, however, when microbial communities assemble, complex organic structures (like fallen leaves from a tree) are disassembled by a network of different microbes acting in conjunction. Primary colonizers will start by enzymatically attacking the surface leaf structure producing intermediate compounds, which are then utilized by another group of microbes as food source. As a handful primary colonizers create many “waste” products out of just a few compounds from the original fallen leaf a myriad of microbial species fall in behind them to consume every resulting waste compound from the first tier. These secondary opportunists produce a slew of waste products themselves, which are in turn food for a third even larger cohort of microbial species. This trend continues on until all traces of the leaf are lost to an infinite cycling of materials in an ever-increasing complexity in the web of life.

Just as a fallen leaf is food for constellation of microbes, man-made objects are subject to the hungry enzymes of the microbial world.
However, as we can clearly see from the increasing concentration of man-made materials in the natural environment, our inventions are largly resistant to microbial attack. Plastics, metal alloys, antibiotics, protectant coatings, fixatives, retardants, are our means of keeping the hungry bugs at bay. But if the plastic rapper your veggies come in lasts for hundreds of years (little bits and pieces of plastic are accumulating in the ocean at an alarming rate) the question begs, “why are we denying our microbial allies their dinner?”

Huge quantities of man-made substances are accumulating in the environment. Durring my visit to Morocco in fall of 2001 I was struck by the blight of plastic bags that had covered the landscape. The thorny tree and shrubs of the North African arid lands we choked by small plastic bags ubiqutusly dispensed at all the markets. The concept of waste in most cultures does not include compounds that do not go “away”. It may be simplistic to suggest but animals (yes us humans are animals) do not collect their own waste. Why would an intelligent being (if that’s what we are) keep its own shit? Then why are we collecting great heaps of “garbage” expending our time and money making vast deposits of rubbish? If tossing a plastic water bottle on the ground was the same as the core of an apple the concept of waste would more closely match our evolved behaviors of dealing with waste. Yet the reality is, these two concepts are marred by a great division bringing us to the current state of devistation.

A reconsideration of the criteria for designing products is due. Materials that fall into their place in the cycle of matter will alleviate the continued accumulation of chemicals in the environment. However, the problem remains: what to do about the tremendous burden that currently afflicts the planet? Well again, microbes to the rescue.

Through careful consideration of microbial systems (largely thanks to the “molecular revolution” or discover DNA and advancements in DNA-based scientific inquiry) and microbial based technologies are beginning to immerge that offer promising new methods of removing chemicals from the environment. Many research labs around the world are investigating the mechanisms utilized by microbes as they break down chemicals to non-toxic natural compounds. By constructing living systems (bioreactors, biofilters and other biological treatments) to treat contaminated material (water, soil and air) biological remediation or bioremediation can dramatically increase the removal rates of man-mad compounds from the environment.

Ushered in by the discovery of bacterial that can eat chemicals (termed biodegradation), adventurous microbiologists have begun microbe-hunting the world’s most toxic waste lands with the hope of finding microbes that can later be used to restore polluted ecosystems. Just like the botanists of years past trekking around the world for plants of unique value, microbe hunters have found useful bugs to treat infectious diseases, create vaccinations etc. No discussion on the early days of microbe hunting would be complete without mention of Paul de Kruif’s book Microbe Hunters gives a thorough discussion of the early pioneers in microbial bioprospecting.

Today the microbe hunters microscopes are focusing on the discovery of bugs to aid in the treatment of environmental diseases in addition to the traditional medical microbiology. Recent discoveries have yielded microbes that can break down a number of environmentally persistent pollutants including petroleum products, pesticides and other agro-chemicals, industrial chemicals such as dioxins, PCPs, PBDEs (flame retardants used to treate furniture and textiles), just to name a few. For the many thousands of pollutants new microbial species are being discovered with the ability to digest the chemicals rendering them harmless or inactive.

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