alpha helix

American  

noun

Biochemistry.

1. the rodlike spatial configuration of many protein molecules in which the polypeptide backbone is stabilized by hydrogen bonds between amino acids in successive helical turns.

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alpha helix British  

noun

1. biochem a helical conformation of a polypeptide chain, found abundantly in the structure of proteins

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alpha helix Scientific  

1. A common structure of proteins, characterized by a single, spiral chain of amino acids stabilized by hydrogen bonds.

2. Compare beta sheet random coil

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Etymology

Origin of alpha helix

First recorded in 1950–55

Example Sentences

Every helical turn in an alpha helix has 3.6 amino acid residues.

From Textbooks • Jun. 9, 2022

Every spiraling alpha helix, every knobby amino acid, all the nooks and crannies.

From Slate • Apr. 9, 2015

In the alpha helix, the bonds form between every fourth amino acid and cause a twist in the amino acid chain.

From Textbooks • Apr. 25, 2013

But we said, "It worked for Linus Pauling when he solved the structure of the alpha helix, so why not for us?"

From Time Magazine Archive

It seemed almost unbelievable that the DNA structure was solved, that the answer was incredibly exciting, and that our names would be associated with the double helix as Pauling’s was with the alpha helix.

From "Double Helix" by James D. Watson