DNAkaksoisjuoste

DNAkaksoisjuoste refers to the double-stranded structure of deoxyribonucleic acid, the molecule that carries genetic instructions. In this structure, two helical strands of nucleotides are wound around each other. Each nucleotide is composed of a phosphate group, a deoxyribose sugar, and a nitrogenous base. The four types of nitrogenous bases are adenine (A), guanine (G), cytosine (C), and thymine (T). These bases form complementary pairs, with adenine always bonding with thymine (A-T) and guanine always bonding with cytosine (G-C), through hydrogen bonds. This specific base pairing ensures that the genetic code is accurately replicated and transcribed.

The two strands run in opposite directions, a characteristic known as antiparallel orientation. One strand runs in the 5' to 3' direction, while the other runs in the 3' to 5' direction. This orientation is crucial for the processes of DNA replication and transcription, as enzymes involved in these processes read the DNA sequence in a specific direction. The double helix is stabilized by the hydrogen bonds between the base pairs and by hydrophobic interactions between the stacked bases. The iconic shape of the DNA double helix was famously elucidated by James Watson and Francis Crick in 1953, based on X-ray diffraction data produced by Rosalind Franklin and Maurice Wilkins. This discovery revolutionized our understanding of genetics and molecular biology.