Beta hairpin
From Wikipedia, the free encyclopedia
The beta hairpin (or beta-beta unit) structural motif is the simplest protein motif involving two beta strands that look like a hairpin. The motif consists of two strands that are adjacent in primary sequence oriented in an antiparallel arrangement (where the N-terminus of one sheet is adjacent to the C-terminus of the next) and linked by a short loop of two to five amino acids. Beta hairpins can occur in isolation or as part of a series of hydrogen bonded strands that collectively comprise a beta sheet.
Researchers such as Francisco Blanco et al. have used protein NMR to show that beta-hairpins can be formed from isolated short peptides in aqueous solution, suggesting that hairpins could form nucleation sites for protein folding.[1]
[edit] References
- ^ Blanco FJ, Rivas G, Serrano L. (1994). A short linear peptide that folds into a native stable beta-hairpin in aqueous solution. Nat Struct Biol 1(9):584-90. PMID 7634098
Protein secondary structure | ||
---|---|---|
Helices: | α-helix | 310 helix | π-helix | β-helix | Polyproline helix | Collagen helix | |
Extended: | β-strand | Turn | Beta hairpin | Beta bulge | α-strand | |
Supersecondary: | Coiled coil | Helix-turn-helix | EF hand | |
Secondary structure propensities of amino acids | ||
Helix-favoring: | Methionine | Alanine | Leucine | Glutamic acid | Glutamine | Lysine | |
Extended-favoring: | Threonine | Isoleucine | Valine | Phenylalanine | Tyrosine | Tryptophan | |
Disorder-favoring: | Glycine | Serine | Proline | Asparagine | Aspartic acid | |
No preference: | Cysteine | Histidine | Arginine | |
←Primary structure | Tertiary structure→ |