Flavodoxin fold
IMage:3chy_flavodoxin_fold.png|thumb|300px|Ribbon diagram of CheY, which adopts the flavodoxin fold. Ribbon is colored from blue to red.
The flavodoxin fold is a common α/β protein fold, second only to the TIM barrel fold. It has three layers, with two α-helical layers sandwiching a 5-stranded parallel β-sheet. The order of strands within the sheet is 2-1-3-4-5.
This motif is present for example in lactate dehydrogenase or phosphoglycerate kinase.