2016
Can We Execute Reliable MM-PBSA Free Energy Computations of Relative Stabilities of Different Guanine Quadruplex Folds?
ISLAM, Barira; Petr STADLBAUER; Stephen NEIDLE; Shozeb HAIDER; Jiří ŠPONER et. al.Základní údaje
Originální název
Can We Execute Reliable MM-PBSA Free Energy Computations of Relative Stabilities of Different Guanine Quadruplex Folds?
Autoři
ISLAM, Barira (356 Indie); Petr STADLBAUER (203 Česká republika); Stephen NEIDLE (826 Velká Británie a Severní Irsko); Shozeb HAIDER (826 Velká Británie a Severní Irsko) a Jiří ŠPONER (203 Česká republika, garant, domácí)
Vydání
Journal of Physical Chemistry B, WASHINGTON, AMER CHEMICAL SOC, 2016, 1520-6106
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10403 Physical chemistry
Stát vydavatele
Velká Británie a Severní Irsko
Utajení
není předmětem státního či obchodního tajemství
Odkazy
Impakt faktor
Impact factor: 3.177
Kód RIV
RIV/00216224:14740/16:00090741
Organizační jednotka
Středoevropský technologický institut
UT WoS
000372946200004
EID Scopus
2-s2.0-84962362096
Klíčová slova anglicky
MOLECULAR-DYNAMICS SIMULATIONS; TELOMERIC G-QUADRUPLEX; AMBER FORCE-FIELD; DNA QUADRUPLEX; NUCLEIC-ACIDS; K+ SOLUTION; STRUCTURAL TRANSITIONS; G-QUARTETS; B-DNA; RNA
Štítky
Změněno: 25. 10. 2016 10:47, Mgr. Eva Špillingová
Anotace
V originále
The self-assembly and stability of DNA G-quadruplexes (GQs) are affected by the intrinsic stability of different GpG base steps embedded in their G-quartet sterns. We have carried out MD simulations followed by MM-PBSA (molecular mechanics Poisson-Boltzmann surface area) free energy calculations on all the experimentally observed three-quartet intramolecular human telomeric GQ topologies. We also studied antiparallel GQ models with alternative syn-anti patterns of the G-quartets. We tested different ions, dihedral variants of the DNA force field, water models, and simulation lengths. In total, similar to 35 mu s of simulations have been carried out. The systems studied here are considerably more complete than the previously analyzed two-quartet stems. Among other effects, our computations included the stem loop coupling and ion ion interactions inside the stem. The calculations showed a broad agreement with the earlier predictions. However, the increase in the completeness of the system was associated with increased noise of the free energy data which could be related, for example, to-the presence of long-lived loop substates and rather complex dynamics-for the. two bound ions inside the G-stem. As a result, the MM-PBSA data, were noisy and we could not improve their quantitative convergence even by expanding the simulations to 2.5 mu s long trajectories. We also suggest that the quality of MM-based free energy computations based on MD simulations of complete GQs is more sensitive to the neglect of explicit polarization effects, which, in real systems, are associated with the presence of multiple closely spaced-ions inside the GQs. Thus, although the MM-PBSA procedure provides very useful insights that complement the structural-dynamics data from MD trajectories of GQs, the method is far from reaching quantitative accuracy. Our conclusions are in agreement with critical assessments of the MM-PBSA methodology available in contemporary literature for other types of problems.
Návaznosti
EE2.3.30.0037, projekt VaV |
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LQ1601, projekt VaV |
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