A toy model for protein folding Equations (2.2) - (2.6) in F.H. Stillinger, Phys. Rev. E 48 (1993), 1469-1477 represent perhaps the simplest nontrivial simplified version of protein folding problems. Each of these problems has exponentially many local optima. ------------- Some results by George Bilchev (G.Bilchev@plymouth.ac.uk) Date: Sun, 21 Apr 1996 17:21:02 BST AAAAA : -2.8482832 at: -0.33595915 -0.62022685 -0.0454332 : using 31608 function calls AAAAB : -1.5894433 at: 0.61898105 0.33748471 -0.068944556 : using 33916 function calls AAABA : -2.4449344 at: 0.29723229 0.33305534 0.62176304 : using 26441 function calls AAABB : -0.54687775 at: 0.61755852 -0.053728351 -0.0017203041 : using 14300 function calls AABAA : -2.5316965 at: 0.32942907 0.62354327 0.045508359 : using 34074 function calls AABAB : -1.3477388 at: -0.33270067 -0.62133097 0.54574605 : using 25018 function calls AABBA : -0.92662111 at: 0.16722304 0.48227704 0.47327397 : using 15127 function calls AABBB : 0.040170229 at: 1.7903939e-09 -1.7903939e-09 1.8302404e-09 : using 21579 function calls ABAAB : -1.3764666 at: 0.62222186 0.33110094 -0.063025283 using 19544 function calls ABABA : -2.2202007 at: 0.61899819 0.04738786 0.61899819 : using 26759 function calls ABABB : -0.61679502 at: 0.61765181 -0.07104446 -0.0022739541 : using 17994 function calls ABBAB : -0.0056451997 at: 0.47879673 0.47340549 -0.14184184 : using 23665 function calls #ABBBA : 0.038705385 at: 1.7903939e-09 -1.8254598e-09 1.7903939e-09 using 15883 function calls ABBBB : -0.065961222 at: 0.054892011 -0.3423645 -0.5617848 : using 29231 function calls BAAAB : -0.52107587 at: 0.039241355 -0.61671205 0.039241364 : using 23301 function calls BAABB : 0.096206698 at: 1.7903939e-09 1.7903939e-09 -1.7903939e-09 : using 13264 function calls BABAB : -0.64802496 at: 0.053274608 -0.61682194 0.053274623 : using 26357 function calls BABBB : -0.18265725 at: 0.56919999 0.33574 0.26659774 : using 26864 function calls BBABB : -0.24020359 at: 0.097386823 0.57642272 0.31772468 : using 17784 function calls BBBBB : -0.45266354 at: 0.34345354 0.5650092 0.09318381 : using 38307 function calls ---------------------------------------------- More toy model articles: F.H. Stillinger and T. Head-Gordon, Collective aspects of protein folding illustrated by a toy model, Phys.Rev.E 52 (1995),No.3, 2872-2877. ftp://thep.lu.se/pub/Preprints/96/lu_tp_96_28.ps.Z F. Potthast, Local interactions and protein folding: A 3D off-lattice approach