While cytoplasmic tryptophanyl-tRNA synthetase (WARS1) ligates tryptophan (Trp) to its cognate tRNAs for protein synthesis, it also plays a role as an innate immune activator in extracellular space. However, its secretion mechanism remains elusive. Here, we report that in response to stimuli, WARS1 can be secreted via two distinct pathways: via Trp-dependent secretion of naked protein and via Trp-independent plasma-membrane-derived vesicles (PMVs).
View Article and Find Full Text PDFFood Sci Biotechnol
December 2021
Unlabelled: This study aimed to develop a mathematical model for the survival of in hamburgers and sandwiches and to evaluate their microbial risk. The primary model was developed in hamburgers using 4 strains of at 5, 10, 15, 25 and 37 °C, and the kinetic parameters of the primary model were fitted well with the Weibull model ( ≥ 0.95).
View Article and Find Full Text PDFHelicobacter pylori colonizes human gastric mucosa. Its infection is associated with gastric diseases including gastric cancer. CagA is one of the most important toxins produced by H.
View Article and Find Full Text PDFTryptophanyl-tRNA synthetase 1 (WARS1) is an endogenous ligand of mammalian Toll-like receptors (TLR) 2 and TLR4. Microarray data, using mRNA from WARS1-treated human peripheral blood mononuclear cells (PBMCs), had indicated WARS1 to mainly activate innate inflammatory responses. However, exact molecular mechanism remains to be understood.
View Article and Find Full Text PDFBackgrounds And Objective: Increased neutrophil infiltration and osteoclast formation are key characteristics of periodontitis. The effect of these neutrophils on osteoclast formation in periodontitis remains unclear. Therefore, we investigated the effects of neutrophils on osteoclast formation in a neutrophil-deficient mouse model of periodontitis.
View Article and Find Full Text PDFInfection with CagA+ Helicobacter pylori strains is linked to an increased risk for gastric diseases, including gastric cancer. Recent evidence indicates that dynamic expansion and contraction of cagA copy number may serve as a novel mechanism to enhance disease development. Herein, comparative genomic analysis divided hpEurope into two groups: hpEurope/type-A and type-B.
View Article and Find Full Text PDFBackground: Periodontitis is an infectious disease that manifests as alveolar bone loss surrounding the roots of teeth. Diabetes aggravates periodontitis-induced alveolar bone loss via suppression of bone formation. Intermittent parathyroid hormone (PTH) administration displays an anabolic effect on bone.
View Article and Find Full Text PDFis associated with hypergastrinemia, which has been linked to the development of gastric diseases. Although the molecular mechanism is not fully understood, is known to modulate the Erk pathway for induction of gastrin expression. Herein we found that an epidermal growth factor (EGF) receptor kinase inhibitor significantly blocked -induced gastrin promoter activity, suggesting involvement of EGF receptor ligands.
View Article and Find Full Text PDFType 1 diabetes with periodontitis shows elevated TNF-α expression. Tumor necrosis factor (TNF)-α stimulates the expression of receptor activator of nuclear factor-κB ligand (RANKL) and sclerostin. The objective of this study was to determine the effect of TNF-α expression of osteocytic RANKL and sclerostin in type 1 diabetes rats with periodontitis using infliximab (IFX), a TNF-α antagonist.
View Article and Find Full Text PDFInfection with is a major risk factor for development of gastric disease, including gastric cancer. Patients infected with strains that express CagA are at even greater risk of gastric carcinoma. Given the importance of CagA, this report describes a new molecular mechanism by which the copy number dynamically expands and contracts in Analysis of strain PMSS1 revealed a heterogeneous population in terms of numbers of copies; strains carried from zero to four copies of that were arranged as direct repeats within the chromosome.
View Article and Find Full Text PDFThe array of outer membrane proteins (OMPs) found in Helicobacter pylori provides a crucial component for persistent colonization within the gastric niche. Not only does H. pylori harbor a wide number of OMPs, but these OMPs often vary across strains; this likely contributes to immune evasion, adaptation during long term colonization, and potentially differential disease progression.
View Article and Find Full Text PDFAreca nut (AN) chewing is a habit in many countries in Central, Southern, and Southeast Asia. It is strongly associated with the occurrence of oral, pharyngeal, and esophageal cancer as well as systemic inflammation. However, the association between AN intake and the development of gastric lesions has not yet been identified.
View Article and Find Full Text PDFHelicobacter pylori (Hp) CagL is a component of the type IV secretion system (T4SS) and interacts with integrin in host cells through its flexible RGD domain to translocate CagA. Differences in CagL amino acid polymorphisms between Western and East-Asian Hps are correlated with clinical outcome. CagL of East-Asian clinical Hp isolate K74 (CagL(K74)) contains multiple residue variations upstream of RGD motif and has different integrin binding affinities compared to those of CagL from Western Hp 26695.
View Article and Find Full Text PDFBackground & Aims: Wogonin is a flavonoid extracted from the root of Scutellaria baicalensis Gerogi. We evaluated the therapeutic effects of wogonin using db/db mice.
Methods: Mice received wogonin or vehicle by oral gavage for 2 weeks.
J Chromatogr B Analyt Technol Biomed Life Sci
April 2012
Nucleotide diphosphate (NDP) sugars are widely present in antibiotics and glycoconjugates, such as protein- and lipid-linked oligosaccharides, where they act as substrates for glycosyltransferase in eukaryotes and prokaryotes. Among NDP sugars, NDP-4-keto sugars are key intermediates in the synthesis of structurally diverse NDP sugars with different functional groups. However, the structural identification of the NDP-4-keto sugars via mass spectrometry (electrospray ionization-mass spectrometry (ESI-MS)) continues to be a challenge because of the carbonyl group in these sugars interferes with ionization process.
View Article and Find Full Text PDFPhosphomannose isomerases (PMIs) in bacteria and fungi catalyze the reversible conversion of D-fructose-6-phosphate to D-mannose-6-phosphate during biosynthesis of GDP-mannose, which is the main intermediate in the mannosylation of important cell wall components, glycoproteins, and certain glycolipids. In the present study, the kinetic parameters of PMI from Streptomyces coelicolor were obtained, and its function on antibiotic production and sporulation was studied. manA (SCO3025) encoding PMI in S.
View Article and Find Full Text PDFLipid rafts are membrane microdomains that function as platforms for signal transduction and membrane trafficking. Tyrosine kinase interacting protein (Tip) of T lymphotropic Herpesvirus saimiri (HVS) is targeted to lipid rafts in T cells and downregulates TCR and CD4 surface expression. Here, we report that the membrane-proximal amphipathic helix preceding Tip's transmembrane (TM) domain mediates lipid raft localization and membrane deformation.
View Article and Find Full Text PDFThe serotonin type 6 (5-HT(6)) receptor is a G-protein coupled receptor (GPCR) coupled to a stimulatory G-protein (G(S)). To identify the structural basis for the interaction of the 5-HT(6) receptor with the G(S) protein, we have dissected the interaction between GST-fusion proteins containing the second intracellular loop (iL2), the third intracellular loop (iL3), or the C-terminal tail of the 5-HT(6) receptor and the alpha subunit of G(S) (Galpha(S)). The direct interaction of iL3 and Galpha(S) was demonstrated by co-immunoprecipitation.
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