Fig. 11.

Extensional flow-induced transformation from an alpha to beta conformation via intramolecular and intermolecular mechanisms: (a) Two nearby alpha helical segments within the same molecule are exposed to extensional flow to such a point where their protein backbones are exposed to each other resulting in an alpha to beta conformation change within a single molecule; (b) When the molecular concentration is high enough, a concentration dependent-bimolecular collision between extensional flow-stretched molecules can produce a dimer that is much more stable than the monomer; (c) However, if the strain-induced stretch is not sufficient to allow close proximity of each alpha helix in a single molecule, then there is a lack of intramolecular product formation, resulting in heat release.