Institute of
bioorganic chemistry

Potato systemin, originally discovered as an octadecapeptide regulator of plant stress responses to herbivore attack, is shown for the first time to possess protective potential against viral pathogens. Under controlled conditions, plants of the commercial potato cultivar "Indigo" were inoculated with the most devastating economically important Potato virus Y (strains PVY^O and PVY^NTN). Foliar spraying of plants with an aqueous solution of potato systemin StPep I, obtained via solid-phase peptide synthesis, led to a substantial reduction in viral accumulation. These findings indicate that the synthetic potato systemin holds strong promise for development as a signaling biostimulant to enhance potato resistance against viral pathogens. The results are published in Biomolecules.

Scientists from IBCh RAS and their colleagues investigated Rip-2, a natural thanatin-like antimicrobial peptide from the bean bug Riptortus pedestris, and found that its enhanced activity may depend on its C-terminal phenylalanine residue. Selection of E. coli clones with reduced Rip-2 susceptibility identified an R76C substitution in LptA, a component of the lipopolysaccharide transport system. Peptide mutagenesis, analysis of natural homologs, and structure-guided modeling allowed the authors to propose a testable model in which Rip-2 Phe18 contributes to LptA-dependent target engagement. The study clarifies the mechanism of action of thanatin-like peptides and may guide the rational design of new antibiotics. Learn more

T cells spot infected and tumour cells by the molecular tags on their surface, and knowing which receptor fits which tag underpins cellular cancer therapies and a new generation of vaccines. A recent independent screen confirmed only about half of the entries in the world’s databases of these matches. Scientists from IBCH RAS and their colleagues have shown how to separate the sound records from the faulty ones: the statistical filter they propose isolates a core of entries that validate experimentally in 81% of cases, against 38% for the rest. Many apparent failures turned out to be annotation errors, not absent recognition. The work is published in Nature Methods. Learn more

Scientists from the Institute of Bioorganic Chemistry of the Russian Academy of Sciences (IBCh RAS) and their colleagues have identified, cloned and characterized the luciferase of the fungus gnat Keroplatus testaceus for the first time. The study strongly suggests that the newly identified enzyme evolved from the storage protein hexamerin, revealing a previously unknown evolutionary pathway for the emergence of bioluminescence in insects. These findings reveal the molecular basis of light emission in dipteran insects and pave the way for the development of new biomedical imaging tools. The study was published in the Journal of Molecular Biology. Learn more

Adaptive NK cells coexpressing KIR and NKG2C receptors are promising antitumor effectors. A team of researchers from the Institute of Bioorganic Chemistry used stimulation with a cytomegalovirus peptide presented within the HLA-E molecule to expand such effectors in vitro, and revealed the dependence of the accumulation of adaptive NK cells possessing high HLA-E-directed cytotoxicity on the NK cell phenotype ex vivo.These findings are of interest for the therapeutic use of NK cells, and also contribute to a better understanding of virus-mediated modulation of NK cell population diversity. The study is supported by RSF grant 26-15-00648 and published in the International Journal of Molecular Science.