Editing Beta sheet (section)

===Greek key motif===
The Greek key motif consists of four adjacent antiparallel strands and their linking loops. It consists of three antiparallel strands connected by hairpins, while the fourth is adjacent to the first and linked to the third by a longer loop. This type of structure forms easily during the [[protein folding]] process.<ref>[http://swissmodel.expasy.org/course/text/chapter4.htm Tertiary Protein Structure and Folds: section 4.3.2.1]. From [http://swissmodel.expasy.org/course/ Principles of Protein Structure, Comparative Protein Modelling, and Visualisation]</ref><ref name="pmid8506258">{{cite journal | vauthors = Hutchinson EG, Thornton JM | title = The Greek key motif: extraction, classification and analysis | journal = Protein Engineering | volume = 6 | issue = 3 | pages = 233–45 | date = April 1993 | pmid = 8506258 | doi = 10.1093/protein/6.3.233 }}</ref> It was named after a pattern common to Greek ornamental artwork (see [[meander (art)|meander]]).