Author: Fadel Fakih

Comparative Genomics and the Boundaries of Molecular Rules

~ Fadel Fakih ~ Leave a comment

The evolution of life on Earth is a history of countless successes and failures. The variations arise through chance, but within physical, chemical, and biological organization and limitations. Natural selection acts on these variations, retaining forms that remain functionally viable, while many other variations persist through neutral evolution, shaped not by adaptive advantages but by … Continue reading Comparative Genomics and the Boundaries of Molecular Rules

DRT3 and the Creativity of Molecular Biology

~ Fadel Fakih ~ Leave a comment

A recent Science paper described an extremely strange antiphage reverse transcriptase system, DRT3. DRT3 is made up of two RT-like proteins, DRT3a and DRT3b, and a non-coding RNA. These assemble into a large ribonucleoprotein complex with six copies of each component. Functionally, the two RTs make opposite strands of an alternating dinucleotide DNA repeat. DRT3a … Continue reading DRT3 and the Creativity of Molecular Biology

The 4-bp anticodon stem tRNA: an anarchist of the genetic code

~ Fadel Fakih ~ Leave a comment

In our genetics 101, we often learn that the genetic code is a strict dictionary. But biology, as we know it, is the wonderland of exceptions. In fact, the genetic code can only be called “nearly universal”, since up to 60 deviations have been described so far (Lukes et al. Curr. Biol., 2025). Departures sometimes … Continue reading The 4-bp anticodon stem tRNA: an anarchist of the genetic code

Why evolution needs noise: in the light of QT45 ribozyme

~ Fadel Fakih ~ Leave a comment

A violet amethyst crystal, while beautiful on the outside, is a highly ordered structure at the microscopic level, and therefore cannot evolve. In contrast, a gas is highly random and cannot store any form of structure or information. Life sits right there in the middle, a highly structured and complex system with a tolerated degree … Continue reading Why evolution needs noise: in the light of QT45 ribozyme

Origin of protein translation: a factory that built itself

~ Fadel Fakih ~ Leave a comment

Information is one of the first words that comes up whenever people try to define life. Any living system must be able to store information and pass them on to the next generation. The stored information are instructions used to build the structures and functions necessary for cellular life to operate such as metabolism, membranes, … Continue reading Origin of protein translation: a factory that built itself

DNA Replication and Convergent Evolution: How Life Reinvented a Core Process

~ Fadel Fakih ~ Leave a comment

Since the very beginning of life, organisms have needed a way to store and pass on information. Current knowledge suggests that the first form of genetic information was stored in ribonucleic acid (RNA). Over time, life invented DNA, a chemically more stable molecule, for long-term information storage and faithful inheritance across generations. This genetic information … Continue reading DNA Replication and Convergent Evolution: How Life Reinvented a Core Process