Transformer protein
Protein able to interconvert between multiple folds / From Wikipedia, the free encyclopedia
A transformer protein (TFP) also known as a metamorphic protein is a protein that can interconvert between two or more shapes (also known as folds) each having a different function.[1][2]
The fold of a protein is defined by how the two-dimensional linear protein polypeptide folds up into a three-dimensional structure. Most proteins adopt a single stable fold. But some proteins have marginal structural stability and can rapidly interconvert between two or more folds.[2] Protein structures in a given environment were thought to be defined completely by their amino acid sequence.[3] These protein structures are usually related to one single physiological protein activity. This hypothesis was, however, challenged by observations that proteins could fold in two alternative conformations, such as the prion proteins which exist in a physiologically active cellular form and an insoluble form.[4]
It has been estimated that up to four percent of proteins may have this fold chaining property.[2] Examples of metamorphic proteins include XCL1, RfaH, and KaiB.[2]