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991.
Journal of Experimental and Theoretical Physics - Density functional calculations in periodic boundary conditions (PBCs) were performed to investigate the structural and electronic properties of...  相似文献   
992.
Journal of Experimental and Theoretical Physics - We developed the parameterized post-Keplerian formalism for hybrid metric-Palatini f(R)-gravity. We obtained analytical expressions in the general...  相似文献   
993.
Journal of Experimental and Theoretical Physics - The electric field and charge distributions in a nanosized truncated metal cone in a strong electric field have been found. The geometry of the...  相似文献   
994.
Physics of Atomic Nuclei - We review studies of vortical motion and the resulting global polarization of $$\Lambda$$ and $$\bar{\Lambda}$$ hyperons in heavy-ion collisions, in particular, within...  相似文献   
995.
Physics of Atomic Nuclei - The formalism of asymptotic normalization coefficients and methods for determining them from experimental nuclear data are discussed. A new method is proposed that uses...  相似文献   
996.
Zahra  S.  Shafaq  B.  Kanwal  B. 《Physics of Atomic Nuclei》2020,83(5):770-772
Physics of Atomic Nuclei - Based on the behavior of elastic scattering of proton and anti-proton at $$\sqrt{s}=1.96$$ TeV for squared four-momentum transfer $$0.26<{-}t<1.2($$ GeV...  相似文献   
997.
Physics of Atomic Nuclei - The quantitative characteristics of the products of dispersion and the cascade of dissipative structures arising in metals under shock-wave loading are determined. The...  相似文献   
998.
Physics of Atomic Nuclei - The article presents the concept of a channel-type reactor with a combined cooled moderator. The moderator consists of ceramic beryllium oxide and a liquid...  相似文献   
999.
Mao  Xuegeng  Shang  Pengjian  Yang  Albert C.  Peng  Chung-Kang 《Nonlinear dynamics》2020,101(4):2357-2368
Nonlinear Dynamics - Distribution entropy has been proved to reveal stability for short time series and to distinguish different classes of series by complexity. However, there still exists some...  相似文献   
1000.
Oncogenic RAS proteins, involved in ∼30% of human tumors, are molecular switches of various signal transduction pathways. Here we apply a new protocol for the NMR study of KRAS in its (inactive) GDP- and (activated) GTP-bound form, allowing a comprehensive analysis of the backbone dynamics of its WT-, G12C- and G12D variants. We found that Tyr32 shows opposite mobility with respect to the backbone of its surroundings: it is more flexible in the GDP-bound form while more rigid in GTP-complexes (especially in WT- and G12D-GTP). Using the G12C/Y32F double mutant, we showed that the presence of the hydroxyl group of Tyr32 has a marked effect on the G12C-KRAS-GTP system as well. Molecular dynamics simulations indicate that Tyr32 is linked to the γ-phosphate of GTP in the activated states – an arrangement shown, using QM/MM calculations, to support catalysis. Anchoring Tyr32 to the γ-phosphate contributes to the capture of the catalytic waters participating in the intrinsic hydrolysis of GTP and supports a simultaneous triple proton transfer step (catalytic water → assisting water → Tyr32 → O1G of the γ-phosphate) leading to straightforward product formation. The coupled flip of negatively charged residues of switch I toward the inside of the effector binding pocket potentiates ligand recognition, while positioning of Thr35 to enter the coordination sphere of the Mg2+ widens the pocket. Position 12 mutations do not disturb the capture of Tyr32 by the γ-phosphate, but (partially) displace Gln61, which opens up the catalytic pocket and destabilizes catalytic water molecules thus impairing intrinsic hydrolysis.

Nucleotide exchange to the physiological, activated, GTP-bound form of KRAS results in the anchoring of Tyr32 within the active site.  相似文献   
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