@article {Olszewski1996, title = {Does a backwardly read protein sequence have a unique native state?}, journal = {Protein Engineering}, volume = {9}, number = {1}, year = {1996}, month = {jan}, pages = {5{\textendash}14}, abstract = {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.}, keywords = {Amino Acid Sequence, Computer Simulation, Models, Molecular, Molecular Sequence Data, Monte Carlo Method, Protein Conformation, Protein Engineering, Protein Folding, Protein Structure, Secondary, Staphylococcal Protein A, Staphylococcal Protein A: chemistry, Tertiary}, issn = {0269-2139}, url = {http://www.ncbi.nlm.nih.gov/pubmed/9053902}, author = {Krzysztof A. Olszewski and Andrzej Koli{\'n}ski and Jeffrey Skolnick} }