A Radical Change in Perspective

I apologize in advance for the pun but I feel that this accurately describes the situation (at least for me). As always, this news comes from our good friends at MIT. Dr. JoAnne Stubbe, professor of chemistry and biology wish to remove the “bad rep” associated with free radicals. Before getting into her explanation, free radicals are molecules or atoms that are unstable due to an unpaired electron or unfilled valence shell (the outermost electron shell of an atom). These factors give free radicals the property of being unstable and are able to react readily with several molecules with little predictability. This reactivity means that radicals can cause unwanted reactions such as with DNA and have been suspected by scientists to be a factor in aging for humans and other living beings.

Dr. JoAnne Stubbe presents the 40th Annual James R. Killian Jr. Faculty Achievement Award Lecture. Photo: Dominick Reuter

With this bad publicity on free radicals in the human body, many companies and scientists have promoted in the consumption of antioxidants to react with the free radicals instead of important molecules such as DNA. In our SCIE300 blog, there are also several posts regarding the consumption of a lot of free radicals to improve health.

However, Dr. Stubbe suggests that free radicals are a misunderstood bunch in the eyes of society. She gives the analogy of free radicals to protestors against the Vietnam War. According to her, the protesters to society, the “radicals,” are “highly reactive […] and wreaked havoc on everything they interacted with.” But to her, the “radicals” were merely acting in reaction to their hostile environment, like the riot police with “guns raised, masks on.” To her, the free radicals react with DNA because DNA happen to be in their way and not letting them contribute to good pathways present in many enzymes.

“This is textbook material” – Mary Fuller, Associate Chair, MIT

There is a good reason for this view: Dr. Stubbe’s research on the enzyme Ribonucleotide reductase (RNR). RNR is an enzyme that converts nucleotides into deoxynucleotides which are incorporated into DNA which means the RNR is essential to all living beings. But what does RNR has to do with free radicals? It turns out that according to Dr. Stubbe, the RNR’s require free radicals for the conversion of nucleotides to work with “exquisite specificity.” The reactivity of radicals is used to form chain reactions into an enzymatic mechanism that ultimately form the deoxynucleotides. With this new information, several possibilities are opened up such as cancer treatment since we can possibly stop RNR to stop uncontrolled DNA and cell replication.

With this new information on free radicals, let’s hope to see more articles on radicals that shine them on a more positive light since according to Dr. Stubbe, “Your life is in their hands.”

Source:
Freeing radicals from their negative connotations.

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