Proteinlike behavior of a spin system near the transition between a ferromagnet and a spin glass

A simple spin system is studied as an analog for proteins. We investigate how the introduction of randomness and frustration into the system affects the designability and stability of ground-state configurations. We observe that the spin system exhibits proteinlike behavior in the vicinity of the transition between a ferromagnet and a spin glass. Our results illuminate some guiding principles in protein evolution. © 2001 The American Physical Society