10. Microbial Ecology and Applied Microbiology
10.4 Biotechnology
Learning Objectives
- Explain the concept of biotechnology and describe some of the earliest examples
- Describe the biotechnological applications of rhizobia, Baculoviruses, Bacillus thuringiensis and Agrobacterium tumifaciens
- Describe the role of genetic modification in agriculture
- Describe some of the diverse uses of microbes in the pharmaceutical industry and medicine
- Distinguish between probiotic bacteria, Faecal Microbial Transplants (FMT) and Microbial Ecosystem Therapy (MET)
Human life is only possible due to the action of microbes, both those in the environment and those species that call us home. Internally, they help us digest our food, produce vital nutrients for us, protect us from pathogenic microbes, and help train our immune systems to function properly. In fact, prokaryotes provide essential services not just to humans, but to all other organisms. Atmospheric nitrogen (N2), can be “fixed,” or converted into ammonia (NH3) by certain species of bacteria and archaea, but not by any eukaryotes, despite the fact that nitrogen is a major macroelement for all life, and in limiting concentrations in terrestrial environments.
Humans have been consuming fermented foods and beverages like beer, wine, bread, yogurt, cheese, and pickled vegetables for all of recorded history. Discoveries from several archeological sites suggest that even prehistoric people took advantage of fermentation to preserve and enhance the taste of food. Archaeologists studying pottery jars from a Neolithic village in China found that people were making a fermented beverage from rice, honey, and fruit as early as 7000 BC.[1] While it is likely that people first learned about fermentation by accident—perhaps by drinking old milk that had curdled or old grape juice that had fermented—they later learned to harness the power of fermentation to make products like bread, cheese, and wine.
According to the United Nations Convention on Biological Diversity, biotechnology is “any technological application that uses biological systems, living organisms, or derivatives thereof, to make or modify products or processes for specific use.”[2] The concept of “specific use” involves some sort of commercial application. Genetic engineering, artificial selection, antibiotic production, and cell culture are current topics of study in biotechnology and will be described in later chapters.
In more recent times, with the advent of recombinant DNA technology, genomics and our increasing understanding of the essential role of the microbes in any ecosystem, including that of the human gut, biotechnology is finding increasing uses in agriculture and medicine. In agriculture it can provide an organic means of fertilization, enhance resistance to disease, pests, and environmental stress to improve both crop yield and quality. Our understanding and use of probiotics has taken on new meaning with medical interventions to restor