Analysis of the Factors Affecting the Configuration of the Anti-parallel G-quadruplex Formed by 22-nt Telomere RNA Fragments / 中国生物化学与分子生物学报

G-quadruplexes with different conformations often exhibit different binding abilities to proteins and play different physiological functions. It is of great significance to analyze the factors affecting the configuration of G-quadruplex to explore its physiological function. Different from DNA, RNA sequences have shown parallel G-quadruplex structures in previous reports. However, we found that the only RNA sequence, the 22-nt telomere RNA fragment (ORN-N, A

Homeopatía y la ley de los infinitesimales / Homeopathy and the Law of Infinitesimals

This paper explains the second elementary law of homeopathy, the Law of the Infinitesimals, on the basis of a kinetic model. When a remedy occurs in the human cell of a healthy person and forms a reaction product (simillimum) that induces the finest medical symptoms of an ill person, then remedies entering the cell of the ill person will form identical simillimum molecules and re-establish the initial equilibrium of the healthy state and cure the ill person. However, this will also induce a molecular crowding in the cells of the ill person. For kinetic reasons this will aggravate the re-establishment of the initial equilibrium and consequently worsen or even interrupt the medical treatment. At a low remedy concentration, the molecular crowding becomes negligible while the formation of the simillimum and the re-establishment of the initial equilibrium will take place continuously and cure the person who is ill

Crowding, molecular volume and plasticity: An assessment involving crystallography, NMR and simulations.

The discrepancy between the X-ray and NMR structures of Mycobacterium tuberculosis peptidyl-tRNA hydrolase in relation to the functionally important plasticity of the molecule led to molecular dynamics simulations. The X-ray and the NMR studies along with the simulations indicated an inverse correlation between crowding and molecular volume. A detailed comparison of proteins for which X-ray and the NMR structures appears to confirm this correlation. In consonance with the reported results of the investigations in cellular compartments and aqueous solution, the comparison indicates that the crowding results in compaction of the molecule as well as change in its shape, which could specifically involve regions of the molecule important in function. Crowding could thus influence the action of proteins through modulation of the functionally important plasticity of the molecule.