%0 Journal Article %J Proceedings of the National Academy of Sciences of the United States of America %D 2008 %T Stabilizing effect of knots on proteins. %A Joanna I. Sulkowska %A Sulkowski, Piotr %A Szymczak, P %A Cieplak, Marek %K Computer Simulation %K Disulfides %K Hot Temperature %K Humans %K Models, Chemical %K Ornithine Carbamoyltransferase %K Protein Folding %K Protein Structure, Secondary %K Stress, Mechanical %X Molecular dynamics studies within a coarse-grained, structure-based model were used on two similar proteins belonging to the transcarbamylase family to probe the effects of the knot in the native structure of a protein. The first protein, N-acetylornithine transcarbamylase, contains no knot, whereas human ormithine transcarbamylase contains a trefoil knot located deep within the sequence. In addition, we also analyzed a modified transferase with the knot removed by the appropriate change of a knot-making crossing of the protein chain. The studies of thermally and mechanically induced unfolding processes suggest a larger intrinsic stability of the protein with the knot. %B Proceedings of the National Academy of Sciences of the United States of America %V 105 %P 19714-9 %8 2008 Dec 16 %G eng %N 50 %R 10.1073/pnas.0805468105