%0 Journal Article %J Protein Engineering %D 1996 %T Does a backwardly read protein sequence have a unique native state? %A Krzysztof A. Olszewski %A Andrzej Koliński %A Jeffrey Skolnick %K Amino Acid Sequence %K Computer Simulation %K Models %K Molecular %K Molecular Sequence Data %K Monte Carlo Method %K Protein Conformation %K Protein Engineering %K Protein Folding %K Protein Structure %K Secondary %K Staphylococcal Protein A %K Staphylococcal Protein A: chemistry %K Tertiary %X Amino acid sequences of native proteins are generally not palindromic. Nevertheless, the protein molecule obtained as a result of reading the sequence backwards, i.e. a retro-protein, obviously has the same amino acid composition and the same hydrophobicity profile as the native sequence. The important questions which arise in the context of retro-proteins are: does a retro-protein fold to a well defined native-like structure as natural proteins do and, if the answer is positive, does a retro-protein fold to a structure similar to the native conformation of the original protein? In this work, the fold of retro-protein A, originated from the retro-sequence of the B domain of Staphylococcal protein A, was studied. As a result of lattice model simulations, it is conjectured that the retro-protein A also forms a three-helix bundle structure in solution. It is also predicted that the topology of the retro-protein A three-helix bundle is that of the native protein A, rather than that corresponding to the mirror image of native protein A. Secondary structure elements in the retro-protein do not exactly match their counterparts in the original protein structure; however, the amino acid side chain contract pattern of the hydrophobic core is partly conserved. %B Protein Engineering %V 9 %P 5–14 %8 jan %G eng %U http://www.ncbi.nlm.nih.gov/pubmed/9053902