Characterization and antioxidant activities of glycosaminoglycans from dried leech
In this study, glycosaminoglycans were isolated from dried leech for the first time and their structures were analyzed by the combination of Fourier-transform infrared spectroscopy, liquid chromatography-ion trap/time-of-flight mass spectrometry and polyacrylamide gel electrophoresis. Heparan sulfate and chondroitin sulfate/dermatan sulfate were detected in dried leech with varied disaccharide compositions and possess a heterogeneous structure. Heparan sulfate species possess an equal amount of total 2-O-sulfated,N-sulfated and acetylated disaccharides, while chondroitin sulfate /dermatan sulfate contain high content of 4-...
Source: Glycoconjugate Journal - February 7, 2023 Category: Biochemistry Source Type: research
Sialoadhesin (CD169/Siglec-1) is an extended molecule that escapes inhibitory cis-interactions and synergizes with other macrophage receptors to promote phagocytosis
AbstractSialoadhesin (CD169/Siglec-1, Sn) is a macrophage receptor that interacts with sialic acids on both host cells and pathogens. It is a type 1 membrane protein with an unusually large number of 17 extracellular immunoglobulin (Ig)-like domains, made up of an N-terminal V-set domain that binds sialic acid and 16 adjacent C2-set domains. The potential importance of 17 Ig domains in Sn for mediating cellular interactions has not been investigated experimentally. In the present study, Chinese Hamster Ovary (CHO) cells were stably transfected with full-length or truncated forms of Sn. Using human red blood cells (RBC) as ...
Source: Glycoconjugate Journal - February 4, 2023 Category: Biochemistry Source Type: research
Improved synthesis of CD22-binding sialosides and its application for further development of potent CD22 inhibitors
In this study, we developed an improved scalable synthetic procedure for sialosides which utilized 1,5-lactam formation as a key step. The improved procedure yielded sialosides incorporating a series of aglycones at the C2 position. Several derivatives with substituted benzyl residues as aglycones were found to bind to mouse CD22 with affinity comparable to that of GSC-718. The new procedure developed in this study affords sialosides in sufficient quantities for cell-based assays, and will facilitate the search for promising CD22 inhibitors that have therapeutic potential. (Source: Glycoconjugate Journal)
Source: Glycoconjugate Journal - January 28, 2023 Category: Biochemistry Source Type: research
Gangliosides as Siglec ligands
AbstractThe structure of a sialoglycan can be translated into to a biological response when it binds to a specific endogenous lectin. Among endogenous sialic acid-binding lectins in humans are those comprising the 15-member Siglec family, most of which are expressed on overlapping sets of immune cells. Endogenous Siglec ligands are sialoglycolipids (gangliosides) and/or sialoglycoproteins, on cell surfaces or in the extracellular milieu, that bind to and initiate signaling by cell surface Siglecs. In the nervous system, where gangliosides are the predominant sialoglycans, Siglec-4 (myelin-associated glycoprotein) on myelin...
Source: Glycoconjugate Journal - January 26, 2023 Category: Biochemistry Source Type: research
Fluorescent GD2 analog for single-molecule imaging
In this report, we describe the first chemical synthesis of a fluorescent ganglioside, GD2. A biophysical analysis of the synthesized analog revealed its raft-philic character, suggesting its potential to aid single-molecule imaging-based investigations into raft-associated interactions. (Source: Glycoconjugate Journal)
Source: Glycoconjugate Journal - January 26, 2023 Category: Biochemistry Source Type: research
Gangliosides as Siglec ligands
AbstractThe structure of a sialoglycan can be translated into to a biological response when it binds to a specific endogenous lectin. Among endogenous sialic acid-binding lectins in humans are those comprising the 15-member Siglec family, most of which are expressed on overlapping sets of immune cells. Endogenous Siglec ligands are sialoglycolipids (gangliosides) and/or sialoglycoproteins, on cell surfaces or in the extracellular milieu, that bind to and initiate signaling by cell surface Siglecs. In the nervous system, where gangliosides are the predominant sialoglycans, Siglec-4 (myelin-associated glycoprotein) on myelin...
Source: Glycoconjugate Journal - January 26, 2023 Category: Biochemistry Source Type: research
Fluorescent GD2 analog for single-molecule imaging
In this report, we describe the first chemical synthesis of a fluorescent ganglioside, GD2. A biophysical analysis of the synthesized analog revealed its raft-philic character, suggesting its potential to aid single-molecule imaging-based investigations into raft-associated interactions. (Source: Glycoconjugate Journal)
Source: Glycoconjugate Journal - January 26, 2023 Category: Biochemistry Source Type: research
Alkali-labile gangliosides
AbstractThe structure and properties of a group of gangliosides modified by mild alkaline treatment are discussed. We will present the occurrence and the structure of gangliosides carrying theN-acetyneuraminic acidO-acetylated in position 9, the Neu5,9Ac2, and of gangliosides carrying a sialic acid that forms a lactone ring. Starting from biochemical data we will discuss the possible biochemical role played by these gangliosides in the processes of cell signaling and maintenance of brain functions. (Source: Glycoconjugate Journal)
Source: Glycoconjugate Journal - January 25, 2023 Category: Biochemistry Source Type: research
Strengths and weaknesses of pneumococcal conjugate vaccines
AbstractMultivalent vaccines addressing an increasing number ofStreptococcus pneumoniae types (7-, 10-, 13-, 15-, 20-valent) have been licensed over the last 22 years. The use of polysaccharide-protein conjugate vaccines has been pivotal in reducing the incidence of invasive pneumococcal disease despite the emergence of non-vaccine serotypes. Notwithstanding its undoubtable success, some weaknesses have called for continuous improvement of pneumococcal vaccination. For instance, despite their inclusion in pneumococcal conjugate vaccines, there are challenges associated with some serotypes. In particular,Streptococcus pneum...
Source: Glycoconjugate Journal - January 18, 2023 Category: Biochemistry Source Type: research
