Engineering hydrogen bonding at tyrosine-201 in the orange carotenoid protein using halogenated analogues.

The Orange Carotenoid Protein (OCP) is a unique water-soluble photoactive protein that plays a critical role in regulating the balance between light harvesting and photoprotective responses in cyanobacteria. The challenge in understanding OCP´s photoactivation mechanism stems from the heterogeneity of the initial configurations of its embedded ketocarotenoid, which in the dark-adapted state can form up to two hydrogen bonds to critical amino acids in the protein's C-terminal domain, and the extremely low quantum yield of primary photoproduct formation. While a series of experiments involving point mutations within these contacts helped us to identify these challenges, they did not resolve them.

High-Risk Lineages of Hybrid Plasmids Carrying Virulence and Carbapenemase Genes.

Carbapenem-resistant (CRE) are a global health threat due to their high morbidity and mortality rates and limited treatment options. This study examines the plasmid-mediated transmission of virulence and antibiotic resistance determinants in carbapenem-resistant () and () isolated from Russian hospitals. : We performed short- and long-read whole-genome sequencing of 53 clinical isolates (48 and 5 ) attributed to 15 genetic lineages and collected from 21 hospitals across nine Russian cities between 2016 and 2022.

Antioxidant properties of the soluble carotenoprotein AstaP and its feasibility for retinal protection against oxidative stress.

Photodamage to the outer segments of photoreceptor cells and their impaired utilization by retinal pigment epithelium (RPE) cells contribute to the development of age-related macular degeneration (AMD) leading to blindness. Degeneration of photoreceptor cells and RPE cells is triggered by reactive oxygen species (ROS) produced by photochemical reactions involving bisretinoids, by-products of the visual cycle, which accumulate in photoreceptor discs and lipofuscin granules of RPE. Carotenoids, natural antioxidants with high potential efficacy against a wide range of ROS, may protect against the cytotoxic properties of lipofuscin.

Accumulation of Li Ions Triggers Changes in , , , and Transcription in the LiCl-Treated Human Umbilical Vein Endothelial Cells (HUVEC).

Changes in intracellular concentrations of Na and K are shown to alter gene expression. Another monovalent cation, Li, is well known as a medicine for treatment of psychiatric disorders, but mechanism of its action is obscure. Thus, it is important to evaluate the effect of Li on gene expression in endothelial cells.