Chemosensory protein 16 has an immune function and participates in host-pathogen interaction in infected with .

Chemosensory protein 16 was identified in the hemolymph of as a protein with an amount increasing after oral infection with 10^3 CFU of , and decreasing after infection with a higher dose (10^5 CFU) of bacteria. The expression of the CSP16 gene occurred in the fat body and in the gut and correlated with changes in the protein level in the hemolymph. The CSP16 protein inhibited growth in the concentration range from 0.

Pro-inflammatory properties of aureocin A53.

Aureocin A53 is a peptide bacteriocin produced by an opportunistic pathogen Staphylococcus aureus strain A53. The spatial structure of aureocin, unlike its amino acid sequence, is similar to the bacteriocin BacSp222, which was recently found to have the ability to induce the inflammatory response in the host cells. The presented research aimed to verify such properties also for aureocin A53.

Despite the odds: formation of the SARS-CoV-2 methylation complex.

Coronaviruses modify their single-stranded RNA genome with a methylated cap during replication to mimic the eukaryotic mRNAs. The capping process is initiated by several nonstructural proteins (nsp) encoded in the viral genome. The methylation is performed by two methyltransferases, nsp14 and nsp16, while nsp10 acts as a co-factor to both.

Immune priming modulates and interaction. Antimicrobial properties of Kazal peptide Pr13a.

larvae repeatedly infected with bacteria re-induced their immune response. Its parameters, i.e.

Defence response of Galleria mellonella larvae to oral and intrahemocelic infection with Pseudomonasentomophila.

We report differences in the course of infection of G. mellonella larvae with P. entomophila via intrahemocelic and oral routes.

BacSp222 bacteriocin as a novel ligand for TLR2/TLR6 heterodimer.

Objective And Design: BacSp222 bacteriocin is a bactericidal and proinflammatory peptide stimulating immune cells to produce selected cytokines and NO in NF-ĸB dependent manner. This study aims to identify the receptor which mediates this activity.

Methods: We applied fluorescently labeled BacSp222 and a confocal microscopy imaging to analyze the direct interaction of the bacteriocin with the cells.

Bacteriocin BacSp222 and Its Succinylated Forms Exhibit Proinflammatory Activities Toward Innate Immune Cells .

Purpose: The zoonotic opportunistic pathogen 222 produces BacSp222 - an atypical peptide exhibiting the features of a bacteriocin, a virulence factor, and a molecule modulating the host inflammatory reaction. The peptide is secreted in an unmodified form and, additionally, two forms modified posttranslationally by succinylation. This study is a comprehensive report focusing on the proinflammatory properties of such molecules.

Cationic protein 8 plays multiple roles in Galleria mellonella immunity.

Galleria mellonella cationic protein 8 (GmCP8) is a hemolymph protein previously identified as an opsonin and an inhibitor of fungal proteases. In this work, we showed its bactericidal activity toward Pseudomonas entomophila, Pseudomonas aeruginosa, Bacillus thuringiensis, Staphylococcus aureus, and Escherichia coli and against yeast-like fungi Candida albicans. The activity against E.

Fungal α-1,3-Glucan as a New Pathogen-Associated Molecular Pattern in the Insect Model Host .

Recognition of pathogen-associated molecular patterns (PAMPs) by appropriate pattern recognition receptors (PRRs) is a key step in activating the host immune response. The role of a fungal PAMP is attributed to β-1,3-glucan. The role of α-1,3-glucan, another fungal cell wall polysaccharide, in modulating the host immune response is not clear.

Structure, Biosynthesis, and Biological Activity of Succinylated Forms of Bacteriocin BacSp222.

BacSp222 is a multifunctional peptide produced by 222. This 50-amino acid long peptide belongs to subclass IId of bacteriocins and forms a four-helix bundle molecule. In addition to bactericidal functions, BacSp222 possesses also features of a virulence factor, manifested in immunomodulatory and cytotoxic activities toward eukaryotic cells.

Human skin microbiota-friendly lysostaphin.

Growing antibiotic resistance of bacteria is a burning problem of human and veterinary medicine. Expansion and introduction of novel microbicidal therapeutics is highly desirable. However, antibiotic treatment disturbs the balance of physiological microbiota by changing its qualitative and/or quantitative composition, resulting in a number of adverse effects that include secondary infections.

A comparison of the production of antimicrobial peptides and proteins by Galleria mellonella larvae in response to infection with two Pseudomonas aeruginosa strains differing in the profile of secreted proteases.

The work presents identification of antimicrobial peptides and proteins (AMPs) in the hemolymph of Galleria mellonella larvae infected with two Pseudomonas aeruginosa strains (ATCC 27,853 and PA18), differing in the profile of secreted proteases. The insects were immunized with bacteria cultivated in rich (LB) and minimal (M9) media, which resulted in appearance of a similar broad set of AMPs in the hemolymph. Among them, 13 peptides and proteins were identified, i.

Isolation, Identification, and Bioinformatic Analysis of Antibacterial Proteins and Peptides from Immunized Hemolymph of Red Palm Weevil .

Red palm weevil ( Olivier, 1791, Coleoptera: Curculionidae) is a destructive pest of palms, rapidly extending its native geographical range and causing large economic losses worldwide. The present work describes isolation, identification, and bioinformatic analysis of antibacterial proteins and peptides from the immunized hemolymph of this beetle. In total, 17 different bactericidal or bacteriostatic compounds were isolated via a series of high-pressure liquid chromatography steps, and their partial amino acid sequences were determined by N-terminal sequencing or by mass spectrometry.

Kallikrein 13 serves as a priming protease during infection by the human coronavirus HKU1.

Human coronavirus HKU1 (HCoV-HKU1) is associated with respiratory disease and is prevalent worldwide, but an in vitro model for viral replication is lacking. An interaction between the coronaviral spike (S) protein and its receptor is the primary determinant of tissue and host specificity; however, viral entry is a complex process requiring the concerted action of multiple cellular elements. Here, we found that the protease kallikrein 13 (KLK13) was required for the infection of human respiratory epithelial cells and was sufficient to mediate the entry of HCoV-HKU1 into nonpermissive RD cells.

Choline Supplementation Sensitizes to Apolipophorin III.

The growth of can be inhibited by apolipophorin III (apoLp-III) which is an insect homologue of human apolipoprotein E., and choline-cultured cells are considerably more susceptible to apoLp-III than bacteria grown without choline supplementation. In the present study, the interactions of apoLp-III with intact cells cultured without and with exogenous choline were analyzed to explain the basis of this difference.

Identification and characterization of spp. and their susceptibility to insect apolipophorin III.

This study investigated the effect of an insect antimicrobial protein, apolipophorin III (apoLp-III), against two newly isolated, identified and characterized clinical strains of spp. Both strains were identified by 16S rRNA sequencing and metabolic and phenotypic profiling. The antibacterial activity of apoLp-III was tested using a colony counting assay.

Antifungal Activity of Anionic Defense Peptides: Insight into the Action of Anionic Peptide 2.

Anionic antimicrobial peptides constitute an integral component of animal innate immunity, however the mechanisms of their antifungal activity are still poorly understood. The action of a unique anionic peptide 2 (AP2) against fungal pathogen was examined using different microscopic techniques and Fourier transform infrared (FTIR) spectroscopy. Although the exposure to AP2 decreased the survival rate of cells, the viability of protoplasts was not affected, suggesting an important role of the fungal cell wall in the peptide action.

Docking interactions determine early cleavage events in insulin proteolysis by pepsin: Experiment and simulation.

In silico modelling of cascade enzymatic proteolysis is an exceedingly complex and challenging task. Here, we study partial proteolysis of insulin by pepsin: a process leading to the release of a highly amyloidogenic two chain 'H-fragment'. The H-fragment retains several cleavage sites for pepsin.

Host-pathogen interactions upon the first and subsequent infection of Galleria mellonella with Candida albicans.

Insects are able to develop enhanced resistance in response to repeated infection. This phenomenon is called immune priming. In this work, so-called "primed" Galleria mellonella larvae were re-infected with a lethal dose of Candida albicans 48 h after injection of a non-lethal dose, while "non-primed" larvae were infected only with a lethal dose.

Identification of Antioxidant Peptides in Enzymatic Hydrolysates of Carp () Skin Gelatin.

The protein by-products from carp () are normally discarded as industrial waste during fish processing. The objective of this study was to identify and characterise the peptides with a potential antioxidant activity that are released from carp skin proteins during hydrolysis by This study shows that a hydrolysate of carp skin gelatin and its reversed-phase chromatography fractions have strong in vitro antioxidant properties. Among these fractions, the alanine-tyrosine (Ala-Tyr) dipeptide was identified as the major compound with high antioxidant potential.

The analysis of human leukocyte antigen-G level in patients with endometrial cancer by Western blot technique.

Problem: Aberrant expression of human leukocyte antigen-G (HLA-G) in various malignancies has been shown to participate in tumour development by suppressing immune regulation within the tumour microenvironment. The detection of HLA-G has reportedly been correlated with certain clinicopathological parameters in several neoplasms. Both the soluble and membranous forms of HLA-G are biologically active, and therefore, we aimed to evaluate the HLA-G level by Western blot technique.

Studies on the interactions of neutral Galleria mellonella cecropin D with living bacterial cells.

Cecropins constitute an important family of insect antimicrobial peptides involved in humoral innate immune response. In comparison with the highly basic cecropins A and B, cecropins D are less cationic and more hydrophobic. Interestingly, cecropins D were described only in lepidopteran insects, e.

Mouse Antibody of IgM Class is Prone to Non-Enzymatic Cleavage between CH1 and CH2 Domains.

IgM is a multivalent antibody which evolved as a first line defense of adaptive immunity. It consists of heavy and light chains assembled into a complex oligomer. In mouse serum there are two forms of IgM, a full-length and a truncated one.

Studies on localization and protein ligands of Galleria mellonella apolipophorin III during immune response against different pathogens.

A lipid-binding protein apolipophorin III (apoLp-III), an exchangeable component of lipophorin particles, is involved in lipid transport and immune response in insects. In Galleria mellonella, apoLp-III binding to high-density lipophorins and formation of low-density lipophorin complexes upon immune challenge was reported. However, an unanswered question remains whether apoLp-III could form different complexes in a pathogen-dependent manner.

Spatial attributes of the four-helix bundle group of bacteriocins - The high-resolution structure of BacSp222 in solution.

BacSp222 is a multifunctional bacteriocin produced by Staphylococcus pseudintermedius strain 222, an opportunistic pathogen of domestic animals. At micromolar concentrations, BacSp222 kills Gram-positive bacteria and is cytotoxic toward mammalian cells, while at nanomolar doses, it acts as an immunomodulatory factor, enhancing nitric oxide release in macrophage-like cell lines. The bacteriocin is a cationic, N-terminally formylated, 50-amino-acid-long linear peptide that is rich in tryptophan residues.