MBAR-enhanced lattice Monte Carlo simulation of the effect of helices on membrane protein aggregation

We study the effect of helical structure on the aggregation of proteins using a simplified lattice protein model with an implicit membrane environment. A recently proposed Monte Carlo approach, which exploits the proven statistical optimality of the MBAR estimator in order to improve simulation efficiency, was used. The results show that with both two and four proteins present, the tendency to aggregate is strongly expedited by the presence of amphipathic helix (APH), whereas a transmembrane helix (TMH) slightly disfavours aggregation. When four protein molecules are present, partially aggregated states (dimers and trimers) were more common when the APH was present, compared with the cases where no helices or only the TMH is present.

[1]  C. Dobson,et al.  Protein misfolding, functional amyloid, and human disease. , 2006, Annual review of biochemistry.

[2]  D. Landau,et al.  Efficient, multiple-range random walk algorithm to calculate the density of states. , 2000, Physical review letters.

[3]  András Szilágyi,et al.  "Pull Moves" for Rectangular Lattice Polymer Models Are Not Fully Reversible , 2012, IEEE/ACM Transactions on Computational Biology and Bioinformatics.

[4]  C. Geyer Markov Chain Monte Carlo Maximum Likelihood , 1991 .

[5]  Helen R Saibil,et al.  The TatA component of the twin-arginine protein transport system forms channel complexes of variable diameter. , 2005, Proceedings of the National Academy of Sciences of the United States of America.

[6]  Hongwei Li,et al.  Solution NMR structure of the TatA component of the twin-arginine protein transport system from gram-positive bacterium Bacillus subtilis. , 2010, Journal of the American Chemical Society.

[7]  Daan Frenkel,et al.  Configurational bias Monte Carlo: a new sampling scheme for flexible chains , 1992 .

[8]  Tracy Palmer,et al.  The twin-arginine translocation (Tat) protein export pathway , 2012, Nature Reviews Microbiology.

[9]  Jun S. Liu,et al.  Biopolymer structure simulation and optimization via fragment regrowth Monte Carlo. , 2007, The Journal of chemical physics.

[10]  C. Dobson,et al.  The amyloid state and its association with protein misfolding diseases , 2014, Nature Reviews Molecular Cell Biology.

[11]  Jian-Sheng Wang Transition Matrix Monte Carlo Method , 1999 .

[12]  A. Kennedy,et al.  Hybrid Monte Carlo , 1988 .

[13]  B. Berks,et al.  Live cell imaging shows reversible assembly of the TatA component of the twin-arginine protein transport system , 2013, Proceedings of the National Academy of Sciences.

[14]  T. Brüser,et al.  An alternative model of the twin arginine translocation system. , 2003, Microbiological research.

[15]  Michael R. Shirts,et al.  Statistically optimal analysis of samples from multiple equilibrium states. , 2008, The Journal of chemical physics.

[16]  K. Hukushima,et al.  Exchange Monte Carlo Method and Application to Spin Glass Simulations , 1995, cond-mat/9512035.

[17]  Hesselbo,et al.  Monte Carlo simulation and global optimization without parameters. , 1995, Physical review letters.

[18]  A. Laio,et al.  Escaping free-energy minima , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[19]  Adam Smith Protein misfolding , 2003, Nature.

[20]  B. Berks The twin-arginine protein translocation pathway. , 2015, Annual review of biochemistry.

[21]  Bernd A. Berg Algorithmic aspects of multicanonical simulations , 1997 .

[22]  K. Dill,et al.  A lattice statistical mechanics model of the conformational and sequence spaces of proteins , 1989 .

[23]  Y. Sugita,et al.  Replica-exchange molecular dynamics method for protein folding , 1999 .

[24]  B. Berks,et al.  Structural model for the protein-translocating element of the twin-arginine transport system , 2013, Proceedings of the National Academy of Sciences.

[25]  B. Berg,et al.  Multicanonical algorithms for first order phase transitions , 1991 .

[26]  C. Dobson Protein folding and misfolding , 2003, Nature.

[27]  B. Berks,et al.  The Tat Protein Export Pathway , 2010, EcoSal Plus.

[28]  Joan-Emma Shea,et al.  Computational studies of protein aggregation: methods and applications. , 2015, Annual review of physical chemistry.

[29]  Sue Whitesides,et al.  A complete and effective move set for simplified protein folding , 2003, RECOMB '03.

[30]  P. Rodger,et al.  Improved estimation of density of states for Monte Carlo sampling via MBAR. , 2015, Journal of chemical theory and computation.

[31]  George Georgiou,et al.  The bacterial twin-arginine translocation pathway. , 2006, Annual review of microbiology.