molecular biology Molecular biology is the branch of biology that seeks to understand the molecular basis of biological activity in and between cells, including biomolecular synthesis, modification, mechanisms, and interactions. The study of chemical and physi ...

, an Anfinsen cage is a model for

protein folding Protein folding is the physical process by which a protein chain is translated to its native three-dimensional structure, typically a "folded" conformation by which the protein becomes biologically functional. Via an expeditious and reproduci ...

used by some cells to improve the production speed and yield of accurate products. Space within a cell is generally limited, and a protein's folding process can be interrupted or modified if it wanders too close to outside forces while it is still in the process of forming. Even worse, the unformed molecules may begin to aggregate uncontrollably, potentially resulting in a disease such as

Alzheimer's Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As t ...

. To prevent this, some cells will enclose actively folding proteins within one or more chaperones, forming a "cage" around them to protect them during their transformation. These cages can also serve to isolate incorrectly formed proteins that may otherwise affect other processes if it were allowed to float freely. The model is named after

Christian B. Anfinsen Christian Boehmer Anfinsen Jr. (March 26, 1916 – May 14, 1995) was an American biochemist. He shared the 1972 Nobel Prize in Chemistry with Stanford Moore and William Howard Stein for work on ribonuclease, especially concerning the conne ...

who first showed

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...

that pure denatured proteins will sometimes refold spontaneously without an energy source.

References

Protein folding {{molecular-biology-stub