Fireflies use bioluminescent signals to communicate with their mates. Luciferase has been thought to be the sole contributor to light color; however, populations of the Photinus pyralis firefly display variation in the color of their emitted signals yet have identical luciferase sequences. Here, we examined whether pigments could be present in the light organs of the twilight-active species P.
View Article and Find Full Text PDFUnlabelled: Whole genome sequencing has revealed that the genome of possesses an uncharacterized 5-gene operon (SAOUHSC_00088-00092 in strain 8325 genome) that encodes factors with functions related to polysaccharide biosynthesis and export, indicating the existence of a new extracellular polysaccharide species. We designate this locus as for staphylococcal surface carbohydrate. We found that the genes were weakly expressed and highly repressed by the global regulator MgrA.
View Article and Find Full Text PDFJ Anim Physiol Anim Nutr (Berl)
May 2024
Advanced glycation end products (AGEs), formed via the Maillard reaction (MR) during processing of foods, have been implicated in inflammatory and degenerative diseases in human beings. Cellular damage is primarily caused by AGE binding with the receptor for AGEs (RAGE) on cell membranes. An isoform of RAGE, soluble RAGE (sRAGE), acts as a decoy receptor binding circulating AGEs preventing cellular activation.
View Article and Find Full Text PDFStreptococcus mutans is commonly associated with dental caries and the ability to form biofilms is essential for its pathogenicity. We recently identified the Pgf glycosylation machinery of S. mutans, responsible for the post-translational modification of the surface-associated adhesins Cnm and WapA.
View Article and Find Full Text PDFIt is well known that influenza A viruses (IAV) initiate host cell infection by binding to sialic acid, a sugar molecule present at the ends of various sugar chains called glycoconjugates. These sugar chains can vary in chain length, structure, and composition. However, it remains unknown if IAV strains preferentially bind to sialic acid on specific glycoconjugate type(s) for host cell infection.
View Article and Find Full Text PDFNature is rich with examples of highly specialized biological materials produced by organisms for functions, including defense, hunting, and protection. Along these lines, velvet worms (Onychophora) expel a protein-based slime used for hunting and defense that upon shearing and dehydration forms fibers as stiff as thermoplastics. These fibers can dissolve back into their precursor proteins in water, after which they can be drawn into new fibers, providing biological inspiration to design recyclable materials.
View Article and Find Full Text PDFGlycosidic linkages in oligosaccharides play essential roles in determining their chemical properties and biological activities. MS has been widely used to infer glycosidic linkages but requires a substantial amount of starting material, which limits its application. In addition, there is a lack of rigorous research on what MS protocols are proper for characterizing glycosidic linkages.
View Article and Find Full Text PDFCholera toxin (CT) is the etiological agent of cholera. Here we report that multiple classes of fucosylated glycoconjugates function in CT binding and intoxication of intestinal epithelial cells. In Colo205 cells, knockout of B3GNT5, the enzyme required for synthesis of lacto- and neolacto-series glycosphingolipids (GSLs), reduces CT binding but sensitizes cells to intoxication.
View Article and Find Full Text PDFStreptococcus mutans is a key pathogen associated with dental caries and is often implicated in infective endocarditis. This organism forms robust biofilms on tooth surfaces and can use collagen-binding proteins (CBPs) to efficiently colonize collagenous substrates, including dentin and heart valves. One of the best characterized CBPs of S.
View Article and Find Full Text PDFThe compositional and structural analysis of GAGs is challenging due to their heterogenous structures. Strong anion exchange (SAX) HPLC can aid in the compositional analysis of GAGs and can separate complex mixtures based on charge and degree of sulfation. Herein we describe the digestion and release of GAGs from tissue, and the compositional analysis using SAX-HPLC.
View Article and Find Full Text PDFAdaptive immune components are thought to exert non-overlapping roles in antimicrobial host defence, with antibodies targeting pathogens in the extracellular environment and T cells eliminating infection inside cells. Reliance on antibodies for vertically transferred immunity from mothers to babies may explain neonatal susceptibility to intracellular infections. Here we show that pregnancy-induced post-translational antibody modification enables protection against the prototypical intracellular pathogen Listeria monocytogenes.
View Article and Find Full Text PDFBackground: In plants, a large diversity of polysaccharides comprise the cell wall. Each major type of plant cell wall polysaccharide, including cellulose, hemicellulose, and pectin, has distinct structures and functions that contribute to wall mechanics and influence plant morphogenesis. In recent years, pectin valorization has attracted much attention due to its expanding roles in biomass deconstruction, food and material science, and environmental remediation.
View Article and Find Full Text PDFOffspring of obese mothers suffer higher risks of type 2 diabetes due to increased adiposity and decreased β cell function. To date, the sex-differences in offspring islet insulin secretion during early life has not been evaluated extensively, particularly prior to weaning at postnatal day 21 (P21). To determine the role of maternal obesity on offspring islet insulin secretion, C57BL/6J female dams were fed chow or western diet from 4 weeks prior to mating to induce maternal obesity.
View Article and Find Full Text PDFSevere traumatic brain injury (sTBI) survivors experience permanent functional disabilities due to significant volume loss and the brain's poor capacity to regenerate. Chondroitin sulfate glycosaminoglycans (CS-GAGs) are key regulators of growth factor signaling and neural stem cell homeostasis in the brain. However, the efficacy of engineered CS (eCS) matrices in mediating structural and functional recovery chronically after sTBI has not been investigated.
View Article and Find Full Text PDFThe emergence of the coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has created the need for development of new therapeutic strategies. Understanding the mode of viral attachment, entry and replication has become a key aspect of such interventions. The coronavirus surface features a trimeric spike (S) protein that is essential for viral attachment, entry and membrane fusion.
View Article and Find Full Text PDFXylans are a major component of plant cell walls. -Acetyl moieties are the dominant backbone substituents of glucuronoxylan in dicots and play a major role in the polymer-polymer interactions that are crucial for wall architecture and normal plant development. Here, we describe the biochemical, structural, and mechanistic characterization of Arabidopsis () xylan -acetyltransferase 1 (XOAT1), a member of the plant-specific Trichome Birefringence Like (TBL) family.
View Article and Find Full Text PDFSialic acid is a common terminal residue of glycans on proteins and acidic sphingolipids such as gangliosides and has important biological functions. The sialylation process is controlled by more than 20 different sialyltransferases, many of which exhibit overlapping functions. Thus, it is difficult to determine the overall biological function of sialylation by targeted deletion of individual sialyltransferases.
View Article and Find Full Text PDFHuman breast milk is an incredibly rich and complex biofluid composed of proteins, lipids and complex carbohydrates, including a diverse repertoire of free human milk oligosaccharides (HMOs). Strikingly, HMOs are not digested by the infant but function as prebiotics for bacterial strains associated with numerous benefits. Considering the broad variety of beneficial effects of HMOs, and the vast number of factors that affect breast milk composition, the analysis of HMO diversity and complexity is of utmost relevance.
View Article and Find Full Text PDFGlycosaminoglycans (GAGs) were extracted from heads of silver-banded whiting (SBW) fish and subjected to preliminary biocompatibility testing per ISO 10993: intracutaneous irritation, maximization sensitization, systemic toxicity, and cytotoxicity. When the GAG solution was injected intradermally, the observed irritation was within ISO limits and comparable to a marketed control. There was no evidence of sensitization, systemic toxicity, or cellular toxicity on the test organisms treated with the GAG mixture from SBW fish heads.
View Article and Find Full Text PDFTicks are important ectoparasites and vectors of numerous human and animal pathogens. Ticks secrete saliva that contains various bioactive materials to evade the host defense system, and often facilitates the pathogen transmission. In addition, the Lone star tick saliva is thought to be the sensitizer in red meat allergy that is characterized by an allergic reaction to glycan moieties carrying terminal galactose-alpha-1,3-galactose (aGal).
View Article and Find Full Text PDFThe original version of this Article contained errors in Figures 1, 3 and 4. In panels b and d of Figure 1, the labels 'Sdc4' were inadvertently replaced by 'Sdc4'. In panels c and d of Figure 3, the labels 'Sdc4' were replaced by 'Sdc2'.
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