It was observed that sialic acid and macromolecules rich in this sugar were able to inhibit the hemagglutination activity (HA) of Bacteroides fragilis strains in low concentrations. Reversion of the HA and also of the adsorption to beads of Sepharose coupled to bovine submaxillary mucin, by this sugar residue corroborated the recognition capacity of the bacterial lectin-like adhesin. However, when erythrocytes were treated with clostridial neuraminidase, an increase in the HA of some strains was observed. Protease treatment of erythrocytes abolished the HA, indicating that cell receptors of B. fragilis are probably a glycoprotein moiety.
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http://dx.doi.org/10.1016/s0934-8840(11)80912-6 | DOI Listing |
Eng Life Sci
January 2025
Analytical Development & Analytical Attribute Science in Biologics Bristol Myers Squibb Devens Massachusetts USA.
This study emphasizes the critical importance of closely monitoring and controlling the sialic acid content in therapeutic glycoproteins, including EPO, interferon-γ, Orencia, Enbrel, and others, as the level of sialylation directly impacts their pharmacokinetics (PK), immunogenicity, potency, and overall clinical performance due to its influence on protein clearance via hepatic asialoglycoprotein receptors (ASGPR). The ASGPR recognizes and binds to glycoproteins exposed to terminal galactose or N-acetylgalactosamine residues, leading to receptor-mediated endocytosis. Recent studies have demonstrated that sialylation of O-linked glycan plays a role in protecting against macrophage galactose lectin (MGL)-mediated clearance.
View Article and Find Full Text PDFRSC Chem Biol
January 2025
Department of Immunology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine Kamigyo-ku 465 Kajii-cho Kyoto 602-8566 Japan
A multiomic study of the structural characteristics of type A and B influenza viruses by means of highly spectrally resolved Raman spectroscopy is presented. Three virus strains, A H1N1, A H3N2, and B98, were selected because of their known structural variety and because they have co-circulated with variable relative prevalence within the human population since the re-emergence of the H1N1 subtype in 1977. Raman signatures of protein side chains tyrosine, tryptophan, and histidine revealed unequivocal and consistent differences for pH characteristics at the virion surface, while different conformations of two C-S bond configurations in and methionine rotamers provided distinct low-wavenumber fingerprints for different virus lineages/subtypes.
View Article and Find Full Text PDFCell
January 2025
Beijing Life Science Academy, Beijing 102200, China; CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, China; National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China. Electronic address:
The ongoing circulation of highly pathogenic avian influenza (HPAI) A (H5N1) viruses, particularly clade 2.3.4.
View Article and Find Full Text PDFAquat Toxicol
January 2025
College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, Henan 471003, China. Electronic address:
The hepatotoxicity of microplastics (MPs) has garnered increasing attention, but their effects on elderly organisms remain inadequately characterized, particularly concerning hepatic stress response patterns in environmental conditions. In this study, a 10-day exposure period of elderly zebrafish to polystyrene microplastics (PS-MPs, 1 µm) was conducted, with exposure concentrations set at 5.6 × 10 µg/L, 5.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Departmento de Biofísica e Radiobiologia, Universidade Federal de Pernambuco, Recife, Pernambuco 50670-901, Brazil. Electronic address:
Mannose-binding lectin (MBL) is an important glycoprotein of the human innate immune system. Furthermore, individuals with sickle cell anemia (SCA) and MBL deficiency seem more susceptible to vaso-occlusive crises, suggesting an MBL role on HbSS red blood cells (RBCs). This study investigated the interaction of MBL with HbA (healthy) and HbSS RBCs using optical tweezers (OT) and atomic force microscopy (AFM).
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