Antioxidant System Response of Freshwater Mussel Anodontacygnea to Cadmium Exposure

Cadmium is one of the widespread toxic substances being hazardous for man as it capable to enter from the environment into animal and plant tissues and spreading along the food chain. We have studied the effect of Cd on the gills and hepatopancreas of the fresh water bivalve mollusks Anodontacygnea. After 12-day acclimation the mollusks were kept for 24 and 72 hours in aquariums with Cd2+ concentrations of 10, 50 and 100 μg/L. Mass-spectrometric analysis has shown that Cd accumulation rate increased with increasing metal concentration in the water. At cadmium concentration of 100 μg/L the mollusk was capable of accumulating up to 0.44 μg of Cd per day. The accumulation of such high metal concentrations in the mollusk tissues did not kill the animals, but signs of oxidative stress, more pronounced in the gills than in the digestive gland, were observed. Exposure to cadmium ions decreased GSH concentration and increase Рx activity in the mollusk gills as early as 24 hours after the beginning of the experiment. Changing the water in the aquarium had a considerable influence on SOD activity in the gills comparable with the effect of the addition of Cd

Antimicrobial and Amyloidogenic Activity of Peptides. Can Antimicrobial Peptides Be Used against SARS-CoV-2?

At present, much attention is paid to the use of antimicrobial peptides (AMPs) of natural and artificial origin to combat pathogens. AMPs have several points that determine their biological activity. We analyzed the structural properties of AMPs, as well as described their mechanism of action and impact on pathogenic bacteria and viruses. Recently published data on the development of new AMP drugs based on a combination of molecular design and genetic engineering approaches are presented. In this article, we have focused on information on the amyloidogenic properties of AMP. This review examines AMP development strategies from the perspective of the current high prevalence of antibiotic-resistant bacteria, and the potential prospects and challenges of using AMPs against infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)

Antioxidant System Response of Freshwater Mussel Anodontacygnea to Cadmium Exposure

Cadmium is one of the widespread toxic substances being hazardous for man as it capable to enter from the environment into animal and plant tissues and spreading along the food chain. We have studied the effect of Cd on the gills and hepatopancreas of the fresh water bivalve mollusks Anodontacygnea. After 12-day acclimation the mollusks were kept for 24 and 72 hours in aquariums with Cd2+ concentrations of 10, 50 and 100 μg/L. Mass-spectrometric analysis has shown that Cd accumulation rate increased with increasing metal concentration in the water. At cadmium concentration of 100 μg/L the mollusk was capable of accumulating up to 0.44 μg of Cd per day. The accumulation of such high metal concentrations in the mollusk tissues did not kill the animals, but signs of oxidative stress, more pronounced in the gills than in the digestive gland, were observed. Exposure to cadmium ions decreased GSH concentration and increase Рx activity in the mollusk gills as early as 24 hours after the beginning of the experiment. Changing the water in the aquarium had a considerable influence on SOD activity in the gills comparable with the effect of the addition of Cd

Amyloidogenic Peptides: New Class of Antimicrobial Peptides with the Novel Mechanism of Activity

Antibiotic-resistant bacteria are recognized as one of the leading causes of death in the world. We proposed and successfully tested peptides with a new mechanism of antimicrobial action “protein silencing” based on directed co-aggregation. The amyloidogenic antimicrobial peptide (AAMP) interacts with the target protein of model or pathogenic bacteria and forms aggregates, thereby knocking out the protein from its working condition. In this review, we consider antimicrobial effects of the designed peptides on two model organisms, E. coli and T. thermophilus, and two pathogenic organisms, P. aeruginosa and S. aureus. We compare the amino acid composition of proteomes and especially S1 ribosomal proteins. Since this protein is inherent only in bacterial cells, it is a good target for studying the process of co-aggregation. This review presents a bioinformatics analysis of these proteins. We sum up all the peptides predicted as amyloidogenic by several programs and synthesized by us. For the four organisms we studied, we show how amyloidogenicity correlates with antibacterial properties. Let us especially dwell on peptides that have demonstrated themselves as AMPs for two pathogenic organisms that cause dangerous hospital infections, and in which the minimal inhibitory concentration (MIC) turned out to be comparable to the MIC of gentamicin sulfate. All this makes our study encouraging for the further development of AAMP. The hybrid peptides may thus provide a starting point for the antibacterial application of amyloidogenic peptides

Is It Possible to Create Antimicrobial Peptides Based on the Amyloidogenic Sequence of Ribosomal S1 Protein of P. aeruginosa?

The development and testing of new antimicrobial peptides (AMPs) represent an important milestone toward the development of new antimicrobial drugs that can inhibit the growth of pathogens and multidrug-resistant microorganisms such as Pseudomonas aeruginosa, Gram-negative bacteria. Most AMPs achieve these goals through mechanisms that disrupt the normal permeability of the cell membrane, which ultimately leads to the death of the pathogenic cell. Here, we developed a unique combination of a membrane penetrating peptide and peptides prone to amyloidogenesis to create hybrid peptide: “cell penetrating peptide + linker + amyloidogenic peptide”. We evaluated the antimicrobial effects of two peptides that were developed from sequences with different propensities for amyloid formation. Among the two hybrid peptides, one was found with antibacterial activity comparable to antibiotic gentamicin sulfate. Our peptides showed no toxicity to eukaryotic cells. In addition, we evaluated the effect on the antimicrobial properties of amino acid substitutions in the non-amyloidogenic region of peptides. We compared the results with data on the predicted secondary structure, hydrophobicity, and antimicrobial properties of the original and modified peptides. In conclusion, our study demonstrates the promise of hybrid peptides based on amyloidogenic regions of the ribosomal S1 protein for the development of new antimicrobial drugs against P. aeruginosa