Amphiphilic Sialic Acid Derivatives as Potential Dual-Specific Inhibitors of Influenza Hemagglutinin and Neuraminidase.

In the shadow of SARS-CoV-2, influenza seems to be an innocent virus, although new zoonotic influenza viruses evolved by mutations may lead to severe pandemics. According to WHO, there is an urgent need for better antiviral drugs. Blocking viral hemagglutinin with multivalent -acetylneuraminic acid derivatives is a promising approach to prevent influenza infection.

Synthesis of Tetravalent Thio- and Selenogalactoside-Presenting Galactoclusters and Their Interactions with Bacterial Lectin PA-IL from .

Synthesis of tetravalent thio- and selenogalactopyranoside-containing glycoclusters using azide-alkyne click strategy is presented. Prepared compounds are potential ligands of lectin PA-IL. is an opportunistic human pathogen associated with cystic fibrosis, and PA-IL is one of its virulence factors.

Newly identified DNA methyltransferases of Ixodes ricinus ticks.

DNA methylation at the fifth position of cytosine (5mC) and at the sixth position of adenine (6 mA) plays an important role in the regulation of the gene expression and, in eukaryotes, is essential for normal development. For Ixodes ricinus, the most common European arthropod vector of human and animal pathogens, the DNA methylation profile and the role of DNA methylation in tick development are still under discussion. Our goal was to analyze the status of I.

Synthesis of β-d-galactopyranoside-Presenting Glycoclusters, Investigation of Their Interactions with Lectin A (PA-IL) and Evaluation of Their Anti-Adhesion Potential.

is an opportunistic human pathogen associated with cystic fibrosis. This bacterium produces, among other virulence factors, a soluble d-galactose-specific lectin PA-IL (LecA). PA-IL plays an important role in the adhesion to the host cells and is also cytotoxic.

Microscopy examination of red blood and yeast cell agglutination induced by bacterial lectins.

Lectins are a group of ubiquitous proteins which specifically recognize and reversibly bind sugar moieties of glycoprotein and glycolipid constituents on cell surfaces. The mutagenesis approach is often employed to characterize lectin binding properties. As lectins are not enzymes, it is not easy to perform a rapid specificity screening of mutants using chromogenic substrates.

Investigation of the Binding Affinity of a Broad Array of l-Fucosides with Six Fucose-Specific Lectins of Bacterial and Fungal Origin.

Series of multivalent α-l-fucoside containing glycoclusters and variously decorated l-fucosides were synthesized to find potential inhibitors of fucose-specific lectins and study the structure-binding affinity relationships. Tri- and tetravalent fucoclusters were built using copper-mediated azide-alkyne click chemistry. Series of fucoside monomers and dimers were synthesized using various methods, namely glycosylation, an azide-alkyne click reaction, photoinduced thiol-en addition, and sulfation.

Selectivity of original C-hexopyranosyl calix[4]arene conjugates towards lectins of different origin.

As a part of ongoing activities towards the design of ligands against pathogenic lectins, a synthesis of original α-C-galacto/α-C-manno/α-C-fucopyranosyl glycomimetics based on a calix[4]arene scaffold and their binding evaluation is described. The interactions of the glycomimetics with seven lectins of various origins were carried out using agglutination inhibition assays. The 1,3-alternate tetra-C-fucosylated ligand and its derivative having a tertBu group at the upper rim of the calix[4]arene scaffold were the most potent towards the AAL lectin family (RSL, AFL, AAL, AOL) and BC2L-C.

Tri- and tetravalent mannoclusters cross-link and aggregate BC2L-A lectin from Burkholderia cenocepacia.

The opportunistic Gram-negative bacterium Burkholderia cenocepacia causes lethal infections in cystic fibrosis patients. Multivalent mannoside derivatives were prepared as potential inhibitors of lectin BC2L-A, one of the virulence factors deployed by B. cenocepacia in the infection process.

Step-By-Step In Vitro Mutagenesis: Lessons From Fucose-Binding Lectin PA-IIL.

Site-directed mutagenesis is a powerful technique which is used to understand the basis of interactions between proteins and their binding partners, as well as to modify these interactions. Methods of rational design that are based on detailed knowledge of the structure of a protein of interest are often used for preliminary investigations of the possible outcomes which can result from the practical application of site-directed mutagenesis. Also, random mutagenesis can be used in tandem with site-directed mutagenesis for an examination of amino acid "hotspots.

New sensitive detection method for lectin hemagglutination using microscopy.

The blood group system AB0 is determined by the composition of terminal oligosaccharides on red blood cells. Thanks to this structural feature, these groups can be recognized by saccharide-recognizing compounds. Lectins are proteins that are able to reversibly bind saccharide structures.

Burkholderia cenocepacia lectin A binding to heptoses from the bacterial lipopolysaccharide.

Bacteria from the Burkholderia cepacia complex (Bcc) cause highly contagious pneumonia among cystic fibrosis (CF) patients. Among them, Burkholderia cenocepacia is one of the most dangerous in the Bcc and is the most frequent cause of morbidity and mortality in CF patients. Indeed, it is responsible of "cepacia syndrome", a deadly exacerbation of infection, that is the main cause of poor outcomes in lung transplantation.

Burkholderia cenocepacia BC2L-C is a super lectin with dual specificity and proinflammatory activity.

Lectins and adhesins are involved in bacterial adhesion to host tissues and mucus during early steps of infection. We report the characterization of BC2L-C, a soluble lectin from the opportunistic pathogen Burkholderia cenocepacia, which has two distinct domains with unique specificities and biological activities. The N-terminal domain is a novel TNF-α-like fucose-binding lectin, while the C-terminal part is similar to a superfamily of calcium-dependent bacterial lectins.

Structural basis for mannose recognition by a lectin from opportunistic bacteria Burkholderia cenocepacia.

Chronic colonization of the lungs by opportunist bacteria such as Pseudomonas aeruginosa and members of the Bcc (Burkholderia cepacia complex) is the major cause of morbidity and mortality among CF (cystic fibrosis) patients. PA-IIL (lecB gene), a soluble lectin from Ps. aeruginosa, has been the subject of much interest because of its very strong affinity for fucose.