Minimal Life

We see different life forms around us. Do you know how synthetic biologists study these various life forms? Let’s take a peep into this through this article.

We know that life arose on Earth with the simplest functional unit called “cell”, about 4 billion years ago. This cell consisted of a self-replicating genetic material, basic metabolism to synthesize energy, some cellular components and a membrane to separate it from its environment. Such cells evolved to form complex multicellular organisms which we see in the present era. As a result, all the life forms on Earth share a common ancestor known as the Last Universal Common Ancestor (LUCA); forming the root of the evolutionary “tree of life” on Earth.

The interdisciplinary synthetic biology domains aim at making understanding of biology easier and finding solutions by applying engineering principles. The artistic synthetic biology world of J. Craig Venter, which is primarily focused on novel creations and modifications, requires a great deal of testing of the designs and biological products to yield desired outcomes. A general testing procedure may comprise of computer-based model systems or it might involve the use of certain cell culture experiments or defined model organisms under laboratory conditions or even human populations. Major breakthroughs in the domain of biology have been made possible because of model organisms in which the experiments have been examined in detail from time to time.

Scientists always try to select the best organisms for their research which could be helpful in their work. One of the foremost aspects is the degree of genetic similarities between a human and the model organism. Other characteristics like small size, easy maintenance and breeding in a lab, short generation time, large number of offspring, scope for easy genetic manipulations and sequenced genome are considered as well. All these characteristics allow a scientist to study and understand the biology of humans. For instance, when we discover the link between a particular gene and a disease, we can find out what that gene does in a model organism as it will develop the disease in a shorter time span due to its short life cycle as compared to humans.

With the idea of reductionism and use of design-build-test-learn (DBTL) strategy  there are 2 defined methodologies in synthetic biology; Top-down methodology involving sequential deletion of non-essential genes from a natural cell followed by analysis of resulting phenotype at each step and the Bottom-up approach which involves chemical synthesis of a minimal genome and its transplantation into appropriate surrogate cytoplasm. In the bottom-up approach, such surrogate environment can be provided by artificially synthesized minimal cells. This particular methodology is providing nascent and most advanced developments to biology.