Institute of
bioorganic chemistry

Sodium channels play an important role in nature — for example, they determine the excitability of the nervous system and muscles. Their selective conductivity has been intensively studied for many decades, but its physicochemical basis is still unclear. In a new theoretical paper, scientists from the Institute of Bioorganic Chemistry have proposed the so-called “secondary chelation” mechanism, in which the spatial organization of water molecules in the hydration shell of the ion plays a key role. The selectivity filter of a bacterial sodium channel is designed to optimally interact with the hydration shell of Na⁺, while the shell of K⁺ is forced to “shrink”, which prevents its passage. The work was published in the journal Structure and was also awarded an illustration on the cover of the issue. Learn more

Protein biosynthesis by the ribosome is one of the most important reactions in nature. The length of the polypeptide chain is strictly determined by the start and stop codons in mRNA. Translation termination is necessary for the timely completion of protein biosynthesis and the release of the polypeptide product from the ribosome. This process is regulated by specific proteins, the so-called "release factors", which recognize stop codons and mediate the hydrolysis of the ester bond in the peptidyl-tRNA molecule localized in the catalytic center of the ribosome. The new study shows the role of the release factor and the 2'-OH group of tRNA in the catalysis of polypeptide cleavage through the formation of a "bridged" cyclic intermediate. The work was published in the journal Science. Learn more

Neuroprotective activity of neuroglobin (Ngb) is presumably based on its redox interaction with cytochrome c (Cyt c), the mechanisms of which have not yet been elucidated. Authors developed a new methodological approach to study the electron transfer between heme proteins based on Raman spectroscopy. We studied the conformational changes in the Cyt c heme and the effect of the protein microenvironment of Cyt c and Ngb hemes on electron transfer between them using developed approach. Obtained data allowed us to propose a step-by-step mechanism of interaction between Ngb and Cyt c. Understanding the mechanisms of interaction between Ngb and Cyt c is necessary for future practical applications related to the therapy of neurodegenerative diseases. The results are published in the International Journal of Biological Macromolecules. Learn more

A team of scientists with the participation of researchers from the Institute of Bioorganic Chemistry RAS has revealed the nature of the green pigment in the bush cricket Tettigonia cantans. It turned out that the bush cricket owes its protective coloration to a chromoprotein with a unique fold that contains two chromophores simultaneously. One of them is a yellow carotenoid, and the other is a blue bilin. The mixture of the two colors results in a bright green coloration, practically indistinguishable from grass and allowing the animal to cleverly hide. The work has been published in PNAS. Learn more

Researchers from Laboratory of Neuroreceptors and Neuroregulators and Laboratory of Biomolecular NMR-Spectroscopy of IBCh RAS, together with the Laboratory of Biological Testing of the BIBCh, isolated and characterized Ms13-1, a new peptide of the sea anemone Metridium senile with a unique 3D-structure and a pronounced selective effect on acid-sensing ion channels ASIC1a. Ms13-1 has a spatial fold named the "Cys-ladder" by the authors, and is a member of a novel structural class. In the nanomolar range, Ms 13-1 acts as a positive allosteric modulator of ASIC1a, and the injection of the peptide into the mouse hind paw causes pain, which is suppressed by the selective antagonist of ASIC1. The work was published in the FEBS Journal and was marked as the Editors' choice for the May issue. Learn more