Dynamic protein composition of Saccharomyces cerevisiae ribosomes in response to multiple stress conditions reflects alterations in translation activity.

Ribosomes, intercellular macromolecules responsible for translation in the cell, are composed of RNAs and proteins. While rRNA makes the scaffold of the ribosome and directs the catalytic steps of protein synthesis, ribosomal proteins play a role in the assembly of the subunits and are essential for the proper structure and function of the ribosome. To date researchers identified heterogeneous ribosomes in different developmental and growth stages. We hypothesized that under stress conditions the heterogeneity of the ribosomes may provide means to prepare the cells for quick recovery. Therefore the aim of the study was the identification of heterogeneity of ribosomal proteins within the ribosomes in response to eleven stress conditions in Saccharomyces cerevisiae, by means of a liquid chromatography/high resolution mass spectrometry (LC-HRMS) and translation activity tests. Out of the total of 74 distinct ribosomal proteins identified in the study 14 small ribosomal subunit (RPS) and 8 large ribosomal subunit (RPL) proteins displayed statistically significant differential abundances within the ribosomes under stress. Additionally, significant alterations in the ratios of 7 ribosomal paralog proteins were observed. Accordingly, the translational activity of yeast ribosomes was altered after UV exposure, during sugar starvation, cold shock, high salt, anaerobic conditions, and amino acid starvation.

Exploring dog antler chews as a novel source of collagen supplementation: extraction and characterization of collagen from red deer antlers.

Collagen is the body's most abundant protein and is primarily found in the skin, bones, tendons, and ligaments of animals and fish. As the interest in collagen supplementation grows, new sources of this protein are continually being introduced. We have confirmed that red deer antlers are a source of type I collagen. We investigated the effects of chemical treatment, temperature, and time on the extractability of collagen from red deer antlers. The optimal conditions for obtaining the highest collagen yield were determined to be: 1) removing noncollagenous proteins at 25°C for 12 h in an alkaline solution, 2) defatting at 25°C using a 1:10 grounded antler:butyl alcohol ratio, and 3) acidic extraction lasting 36 h using a 1:10 antler:acetic acid ratio. Under these conditions, we obtained a collagen yield of 22.04%. The molecular characterization of red deer antler collagen revealed typical features of type I collagens, including the presence of three α-chains, high glycine content, and high levels of proline and hydroxyproline, as well as helical arrangements. This report suggests that red deer antlers have significant potential as a source of collagen supplements.