CH391L/S12/Synthetic Cooperation

Synthetic Cooperation

Through recent advances in synthetic biology that allow population level control of stability and dynamics, synthetic biologists are able to reliably control population composition and function. These advances give way to developing more complex ecosystems that can involve multiple microbials growing in consortium. These communities can achieve a variety of functions that may be difficult or impossible for a single microbe to perform on its own. By combining this with new techniques for computation and prediction, optimizing synthetic consortia to provide new methods in the field of bioprocessing, healthcare, and communication are possible.

Benefits

Synthetic consortia have a number of advantages over a single population that makes it beneficial to engineer new systems. Consortia are capable of more complex functions than are possible in individual populations. They also are more robust to environmental fluctuations such as nutrient depletion, invasion of foreign populations, and evolutionary mutations across generations. It is often difficult or impossible to engineer a single microbe to perform two or more tasks. This can be overcome by compartmentalizing the functions desired in different populations within the same culture. To achieve this the cells must be able to communicate with one another. This can accomplished by trading metabolites, as will be discussed later, or by exchange of dedicated molecular signals otherwise known as quorum sensing. This concept is discussed in detail here.

Challenges

Major challenges develop when trying to engineer multiple, interacting populations. Among these the most difficult aspect is control of populations over time. With natural, single populations, maintaining homeostasis is relatively simple, as members in the population typically do not out compete each other, nor do they exhaust their supply of resources. For multiple populations that are synthetically designed, this task become increasingly difficult. This is due to the tendency of genetic composition in these organisms to change over time as they adapt to their environments. To overcome this difficulty, the consortia should be designed such that members of the consortium can be re-introduced or eliminated as needed, and more importantly, be monitored over time.

The second challenge facing development of synthetic consortia is that gene transfer, at least in the case of natural microbials, is common. This issue needs to be taken into account to ensure the function of the community is not disrupted due to these changes. Another challenge is the ability to incorporate stable changes into the genomes of microbes that are not currently commonly engineered.

Finally,