  Protein denaturing induced by supercooling is interpreted as a process where
some or all internal symmetries of the native protein are spontaneously broken.
Hence, the free-energy potential corresponding to a folding-funnel landscape
becomes temperature-dependent and describes a phase transition. The idea that
deformed vortices could be produced in the transition induced by temperature
quenching, from native proteins to unfolded conformations is discussed in terms
of the Zurek mechanism that implements the analogy between vortices, created in
the laboratory at low energy, and the cosmic strings which are thought to have
been left after symmetry breaking phase transitions in the early universe. An
experiment is proposed to test the above idea which generalizes the
cosmological analogy to also encompass biological systems and push a step ahead
the view that protein folding is a biological equivalent of the big bang.
