Last Wednesday, Oct 3rd, the Royal Swedish Academy of Sciences announced the winners of 2018 Nobel Prize in Chemistry: Frances H. Arnold, George P. Smith, and Sir Gregory P. Winter. The trio was awarded for their work that "harnessed the power of evolution" to benefit humanity.
Natural selection, the foundation of evolution, a key mechanism advanced by Charles Darwin in his book On the Origin of Species. He theorized that species have different probabilities for survival and successful reproduction due to their phenotypical difference.
But people aren't necessarily familiar with a related but contradictory concept which inspired Darwin, known as artificial selection. Humans have been using selective breeding to purposefully develop particular phenotypic traits of animals and plants. This is how domesticated versions of cats, cattle, and agricultural crops such as rice and maize come into existence.
Arnold is the pioneer in the use of directed evolution to engineer enzymes. The goal of her research was to develop an efficient enzyme that turns biomass that's rich in fiber to alcohol-based biofuel. Unlike her peer, who hung up on structural design, Arnold took a biology-oriented approach.
She sent the genome of the candidate protein into a cycle of mutation-screening-reproduction. After introducing random mutations, she screened the resulted proteins for improved enzymatic functions. Upon finding a mutation that improves the proteins' function, she iterated the process to optimize it further.
This success of her strategy brought in a variety of implications. It has been used to design proteins for diverse applications, from the production of renewable biofuels to the green chemistry behind the synthesis of pharmaceuticals.
On the other hand, Smith and Winter earned their Nobel recognition through their work on for the phage display of peptides and antibodies.
Phage, or bacteriophage, is a type of virus that invade and "devour"--according to its etymology--bacteria. First described by Smith, phage display is a technique that can insert a specific protein sequence into the coat protein gene and cause the protein to be expressed on the outside of the bacteriophage. As he noted in his 1985 paper, the fusion phage can enable to a simpler method of cloning a gene "when an antibody against the product of that gene is available."
Winter took the idea a step forward: he invented techniques to generate humanized mouse monoclonal antibodies that don't elicit responses from the human immune system. The success of his pioneering work led to the commercialization of adalimumab, the first-of-its-kind antibody treatment for rheumatoid arthritis.
Despite having been trained as chemists, Arnold, Smith, and Winter converged on the path of biology-oriented approaches and started a revolution in chemistry for the sake of humankind.
2018 Nobel Prize in Chemistry: Directed evolution & phage display explained (CEN Online)
Source: Nobel Prize
