Topic

DNA structure

Episodes and research papers from From First Principles that help explain DNA structure from the ground up.

Research

Papers and studies featured by the show.

Nature·

Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid

Imagine DNA as a twisted ladder (the famous "double helix"). The sides of the ladder are made of sugar and phosphate molecules, while the rungs are pairs of chemical letters (A, T, G, C) that always pair up in the same way - A with T, and G with C. This pairing rule is like having a perfect template: if you know one side of the ladder, you can figure out exactly what the other side looks like. This is how cells copy DNA when they divide, ensuring that genetic information gets passed along accurately from cell to cell and parent to child.

Nature·

Molecular Configuration in Sodium Thymonucleate

Imagine DNA as a twisted ladder or spiral staircase - that's what we call a "helix." Before this research, scientists knew DNA was important for heredity but didn't know what it looked like. Franklin and Gosling used a technique called X-ray crystallography, which is like taking a shadow picture of molecules using X-rays instead of regular light. When they aimed X-rays at DNA crystals, the shadows they captured showed a distinctive pattern that revealed DNA's twisted shape. They also discovered that DNA can change its form depending on how much moisture is around it, and that the "backbone" of the DNA molecule (the phosphate groups) sits on the outside of the structure. This was like finally seeing the blueprint of life itself.