Related topics: dna

Biosynthesis pathway of a new DNA nucleobase elucidated

DNA is composed of nucleobases represented by the letters A, T, G and C. They form the basis of the genetic code and are present in all living beings. But in a bacteriophage, another base, represented by the letter Z, exists. ...

New approach can add diversity to crop species without breeding GMOs

Breeding better crops through genetic engineering has been possible for decades, but the use of genetically modified plants has been limited by technical challenges and popular controversies. A new approach potentially solves ...

DNA structure itself is involved in genome regulation

The (when stretched) two-meter-long DNA molecule in each human cell is continuously being unpacked and packed again to enable the expression of genetic information. When genes must be accessed for transcription, the DNA double ...

Dynamic 3-D printing process features a light-driven twist

The speed of light has come to 3-D printing. Northwestern University engineers have developed a new method that uses light to improve 3-D printing speed and precision while also, in combination with a high-precision robot ...

Origami with DNA

T-cells are an important component of our immune system: with the receptors they carry on their surface, they can recognize highly specific antigens. Upon detection of an intruder, an immune response is triggered. It is still ...

Molecular forces: The surprising stretching behavior of DNA

When large forces act on a heavy beam, for example, in bridge construction, the beam will be slightly deformed. Calculating the relationship between forces, internal stresses and deformations is one of the standard tasks ...

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Double helix

In geometry a double helix (plural helices) typically consists of two congruent helices with the same axis, differing by a translation along the axis, which may or may not be half-way.

The term "double helix" is commonly encountered in molecular biology, where it refers to the structure of DNA. The double-helix model of DNA structure was first published in the journal Nature by James D. Watson and Francis Crick in 1953, based upon the crucial X-ray diffraction image of DNA (labeled as "Photo 51") from Rosalind Franklin in 1952 , followed by her more clarified DNA image with Raymond Gosling, Maurice Wilkins, Alexander Stokes and Herbert Wilson, as well as base-pairing chemical and biochemical information by Erwin Chargaff.

Crick, Wilkins and Watson each received one third of the 1962 Nobel Prize in Physiology or Medicine for their contributions to the discovery. (Franklin, whose breakthrough X-ray diffraction data was used to formulate the DNA structure, died in 1958, and thus was ineligible to be nominated for a Nobel Prize.)

The DNA double helix is a right-handed spiral polymer of nucleic acids, held together by nucleotides which base pair together. A single turn of the helix constitutes ten nucleotides. The double helix structure of DNA contains a major groove and minor groove, the major groove being wider than the minor groove. Given the difference in widths of the major groove and minor groove, many proteins which bind to DNA do so through the wider major groove .

The order, or sequence, of the nucleotides in the double helix within a gene specifies the primary structure of a protein.

The term entered popular culture with the publication in 1968 of The Double Helix: A Personal Account of the Discovery of the Structure of DNA, by James Watson.

This text uses material from Wikipedia, licensed under CC BY-SA