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Molecules (Basel, Switzerland) Mar 2024Membrane-based sensors (MePSs) exhibit remarkable precision and sensitivity in detecting pressure changes. MePSs are commonly used to monitor catalytic reactions in...
Membrane-based sensors (MePSs) exhibit remarkable precision and sensitivity in detecting pressure changes. MePSs are commonly used to monitor catalytic reactions in solution, generating gas products crucial for signal amplification in bioassays. They also allow for catalyst quantification by indirectly measuring the pressure generated by the gaseous products. This is particularly interesting for detecting enzymes in biofluids associated with disease onset. To enhance the performance of a MePS, various structural factors influence membrane flexibility and response time, ultimately dictating the device's pressure sensitivity. In this study, we fabricated MePSs using polydimethylsiloxane (PDMS) and investigated how structural modifications affect the Young's modulus () and residual stress () of the membranes. These modifications have a direct impact on the sensors' sensitivity to pressure variations, observed as a function of the volume of the chamber () or of the mechanical properties of the membrane itself (). MePSs exhibiting the highest sensitivities were then employed to detect catalyst quantities inducing the dismutation of hydrogen peroxide, producing dioxygen as a gaseous product. As a result, a catalase enzyme was successfully detected using these optimized MePSs, achieving a remarkable sensitivity of (22.7 ± 1.2) µm/nM and a limit of detection (LoD) of 396 pM.
Topics: Catalase; Membranes; Biological Assay; Catalysis; Elastic Modulus; Gases
PubMed: 38611786
DOI: 10.3390/molecules29071506 -
Cells Feb 2024At the intestinal front, several lines of defense are in place to resist infection and injury, the mucus layer, gut microbiome and strong epithelial junctions, to name a... (Review)
Review
At the intestinal front, several lines of defense are in place to resist infection and injury, the mucus layer, gut microbiome and strong epithelial junctions, to name a few. Their collaboration creates a resilient barrier. In intestinal disorders, such as inflammatory bowel disease (IBD), barrier function is compromised, which results in rampant inflammation and tissue injury. In response to the destruction, the intestinal epithelium releases adenosine, a small but powerful nucleoside that functions as an alarm signal. Amidst the chaos of inflammation, adenosine aims to restore order. Within the scope of its effects is the ability to regulate intestinal epithelial barrier integrity. This review aims to define the contributions of adenosine to mucus production, microbiome-dependent barrier protection, tight junction dynamics, chloride secretion and acid-base balance to reinforce its importance in the intestinal epithelial barrier.
Topics: Humans; Adenosine; Inflammatory Bowel Diseases; Inflammation; Intestinal Mucosa
PubMed: 38474346
DOI: 10.3390/cells13050381 -
Biochimica Et Biophysica Acta.... Dec 2023There is a growing interest in the use of microbial cell factories to produce butanol, an industrial solvent and platform chemical. Biobutanol can also be used as a...
There is a growing interest in the use of microbial cell factories to produce butanol, an industrial solvent and platform chemical. Biobutanol can also be used as a biofuel and represents a cleaner and more sustainable alternative to the use of conventional fossil fuels. Solventogenic Clostridia are the most popular microorganisms used due to the native expression of butanol synthesis pathways. A major drawback to the wide scale implementation and development of these technologies is the toxicity of butanol. Various membrane properties and related functions are perturbed by the interaction of butanol with the cell membrane, causing lower yields and higher purification costs. This is ultimately why the technology remains underemployed. This study aimed to develop a deeper understanding of butanol toxicity at the membrane to determine future targets for membrane engineering. Changes to the lipidome in Clostridium saccharoperbutylacetonicum N1-4 (HMT) throughout butanol fermentation were investigated with thin layer chromatography and mass spectrometry. By the end of fermentation, levels of phosphatidylglycerol lipids had increased significantly, suggesting an important role of these lipid species in tolerance to butanol. Using membrane models and in vitro assays to investigate characteristics such as permeability, fluidity, and swelling, it was found that altering the composition of membrane models can convey tolerance to butanol, and that modulating membrane fluidity appears to be a key factor. Data presented here will ultimately help to inform rational strain engineering efforts to produce more robust strains capable of producing higher butanol titres.
Topics: Butanols; 1-Butanol; Clostridium; Membranes
PubMed: 37648011
DOI: 10.1016/j.bbamem.2023.184217 -
BMC Medical Genomics Aug 2023Osteoarthritis is a very common clinical disease in middle-aged and elderly individuals, and with the advent of ageing, the incidence of this disease is gradually...
BACKGROUND
Osteoarthritis is a very common clinical disease in middle-aged and elderly individuals, and with the advent of ageing, the incidence of this disease is gradually increasing. There are few studies on the role of basement membrane (BM)-related genes in OA.
METHOD
We used bioinformatics and machine learning methods to identify important genes related to BMs in OA patients and performed immune infiltration analysis, lncRNA‒miRNA-mRNA network prediction, ROC analysis, and qRT‒PCR.
RESULT
Based on the results of machine learning, we determined that LAMA2 and NID2 were the key diagnostic genes of OA, which were confirmed by ROC and qRT‒PCR analyses. Immune analysis showed that LAMA2 and NID2 were closely related to resting memory CD4 T cells, mast cells and plasma cells. Two lncRNAs, XIST and TTTY15, were simultaneously identified, and lncRNA‒miRNA‒mRNA network prediction was performed.
CONCLUSION
LAMA2 and NID2 are important potential targets for the diagnosis and treatment of OA.
Topics: Aged; Middle Aged; Humans; RNA, Long Noncoding; MicroRNAs; Basement Membrane; Biomarkers; Machine Learning; Osteoarthritis; RNA, Messenger
PubMed: 37612746
DOI: 10.1186/s12920-023-01601-z -
Cell Reports Aug 2023A previously undescribed mechanism underlying butterfly wing coloration patterns was discovered in two distantly related butterfly species, Siproeta stelenes and...
A previously undescribed mechanism underlying butterfly wing coloration patterns was discovered in two distantly related butterfly species, Siproeta stelenes and Philaethria diatonica. These butterflies have bright green wings, but the color pattern is not derived from solid pigments or nanostructures of the scales or from the color of the cuticular membrane but rather from a liquid retained in the wing membrane. Wing structure differs between the green and non-green areas. In the non-green region, the upper and lower cuticular membranes are attached to each other, whereas in the green region, we observed a space of 5-10 μm where green liquid is held and living cells are present. A pigment analysis and tracer experiment revealed that the color of the liquid is derived from hemolymph components, bilin and carotenoid pigments. This discovery broadens our understanding of the diverse ways in which butterfly wings obtain their coloration and patterns.
Topics: Animals; Pigmentation; Butterflies; Wings, Animal; Membranes; Nanostructures
PubMed: 37537843
DOI: 10.1016/j.celrep.2023.112917 -
Nature Communications Sep 2023Microbial synthesis of nutraceutically and pharmaceutically interesting plant polyphenols represents a more environmentally friendly alternative to chemical synthesis or...
Microbial synthesis of nutraceutically and pharmaceutically interesting plant polyphenols represents a more environmentally friendly alternative to chemical synthesis or plant extraction. However, most polyphenols are cytotoxic for microorganisms as they are believed to negatively affect cell integrity and transport processes. To increase the production performance of engineered cell factories, strategies have to be developed to mitigate these detrimental effects. Here, we examine the accumulation of the stilbenoid resveratrol in the cell membrane and cell wall during its production using Corynebacterium glutamicum and uncover the membrane rigidifying effect of this stilbenoid experimentally and with molecular dynamics simulations. A screen of free fatty acid supplements identifies palmitelaidic acid and linoleic acid as suitable additives to attenuate resveratrol's cytotoxic effects resulting in a three-fold higher product titer. This cost-effective approach to counteract membrane-damaging effects of product accumulation is transferable to the microbial production of other polyphenols and may represent an engineering target for other membrane-active bioproducts.
Topics: Polyphenols; Fatty Acids, Nonesterified; Resveratrol; Membranes; Cell Membrane
PubMed: 37699874
DOI: 10.1038/s41467-023-40947-x -
BMC Biology Feb 2024Membranes are protein and lipid structures that surround cells and other biological compartments. We present a conceptual model wherein all membranes are organized into...
Membranes are protein and lipid structures that surround cells and other biological compartments. We present a conceptual model wherein all membranes are organized into structural and functional zones. The assembly of zones such as receptor clusters, protein-coated pits, lamellipodia, cell junctions, and membrane fusion sites is explained to occur through a protein-lipid code. This challenges the theory that lipids sort proteins after forming stable membrane subregions independently of proteins.
Topics: Proteolipids; Membranes; Carrier Proteins; Cell Membrane
PubMed: 38414038
DOI: 10.1186/s12915-024-01849-6 -
Microbiome Nov 2023Intestinal epithelial cell (IEC) mitochondrial dysfunction involvement in inflammatory bowel diseases (IBD), including Crohn's disease affecting the small intestine, is...
BACKGROUND
Intestinal epithelial cell (IEC) mitochondrial dysfunction involvement in inflammatory bowel diseases (IBD), including Crohn's disease affecting the small intestine, is emerging in recent studies. As the interface between the self and the gut microbiota, IECs serve as hubs of bidirectional cross-talk between host and luminal microbiota. However, the role of mitochondrial-microbiota interaction in the ileum is largely unexplored. Prohibitin 1 (PHB1), a chaperone protein of the inner mitochondrial membrane required for optimal electron transport chain function, is decreased during IBD. We previously demonstrated that mice deficient in PHB1 specifically in IECs (Phb1) exhibited mitochondrial impairment, Paneth cell defects, gut microbiota dysbiosis, and spontaneous inflammation in the ileum (ileitis). Mice deficient in PHB1 in Paneth cells (epithelial secretory cells of the small intestine; Phb1) also exhibited mitochondrial impairment, Paneth cell defects, and spontaneous ileitis. Here, we determined whether this phenotype is driven by Phb1 deficiency-associated ileal microbiota alterations or direct effects of loss of PHB1 in host IECs.
RESULTS
Depletion of gut microbiota by broad-spectrum antibiotic treatment in Phb1 or Phb1 mice revealed a necessary role of microbiota to cause ileitis. Using germ-free mice colonized with ileal microbiota from Phb1-deficient mice, we show that this microbiota could not independently induce ileitis without host mitochondrial dysfunction. The luminal microbiota phenotype of Phb1 mice included a loss of the short-chain fatty acid butyrate. Supplementation of butyrate in Phb1-deficient mice ameliorated Paneth cell abnormalities and ileitis. Phb1-deficient ileal enteroid models suggest deleterious epithelial-intrinsic responses to ileal microbiota that were protected by butyrate.
CONCLUSIONS
These results suggest a mutual and essential reinforcing interplay of gut microbiota and host IEC, including Paneth cell, mitochondrial health in influencing ileitis. Restoration of butyrate is a potential therapeutic option in Crohn's disease patients harboring epithelial cell mitochondrial dysfunction. Video Abstract.
Topics: Humans; Animals; Mice; Crohn Disease; Gastrointestinal Microbiome; Ileitis; Inflammation; Inflammatory Bowel Diseases; Paneth Cells; Butyrates; Mitochondria; Intestinal Mucosa
PubMed: 37978573
DOI: 10.1186/s40168-023-01686-9 -
World Journal of Gastroenterology Apr 2024Several features of drug-induced mucosal alterations have been observed in the upper gastrointestinal tract, the esophagus, stomach, and duodenum. These include... (Review)
Review
Several features of drug-induced mucosal alterations have been observed in the upper gastrointestinal tract, the esophagus, stomach, and duodenum. These include pill-induced esophagitis, desquamative esophagitis, worsening of gastroesophageal reflux, chemotherapy-induced esophagitis, proton pump inhibitor-induced gastric mucosal changes, medication-induced gastric erosions and ulcers, pseudomelanosis of the stomach, olmesartan-related gastric mucosal inflammation, lanthanum deposition in the stomach, zinc acetate hydrate tablet-induced gastric ulcer, immune-related adverse event gastritis, olmesartan-asso-ciated sprue-like enteropathy, pseudomelanosis of the duodenum, and lanthanum deposition in the duodenum. For endoscopists, acquiring accurate knowledge regarding these diverse drug-induced mucosal alterations is crucial not only for the correct diagnosis of these lesions but also for differential diag-nosis of other conditions. This minireview aims to provide essential information on drug-induced mucosal alterations observed on esophagogastroduodenoscopy, along with representative endoscopic images.
Topics: Humans; Endoscopy, Digestive System; Gastric Mucosa; Intestinal Mucosa; Proton Pump Inhibitors; Esophageal Mucosa
PubMed: 38690017
DOI: 10.3748/wjg.v30.i16.2220 -
International Journal of Molecular... Aug 2023In this study, bipolar membrane electrodialysis was proposed to directly convert L-ornithine monohydrochloride to L-ornithine. The stack configuration was optimized in...
In this study, bipolar membrane electrodialysis was proposed to directly convert L-ornithine monohydrochloride to L-ornithine. The stack configuration was optimized in the BP-A (BP, bipolar membrane; A, anion exchange membrane) configuration with the Cl ion migration through the anion exchange membrane rather than the BP-A-C (C, cation exchange membrane) and the BP-C configurations with the L-ornithine ion migration through the cation exchange membrane. Both the conversion ratio and current efficiency follow BP-A > BP-A-C > BP-C, and the energy consumption follows BP-A < BP-A-C < BP-C. Additionally, the voltage drop across the membrane stack (two repeating units) and the feed concentration were optimized as 7.5 V and 0.50 mol/L, respectively, due to the low value of the sum of H ions leakage (from the acid compartment to the base compartment) and OH ions migration (from the base compartment to the acid compartment) through the anion exchange membrane. As a result, high conversion ratio (96.1%), high current efficiency (95.5%) and low energy consumption (0.31 kWh/kg L-ornithine) can be achieved. Therefore, bipolar membrane electrodialysis is an efficient, low energy consumption and environmentally friendly method to directly convert L-ornithine monohydrochloride to L-ornithine.
Topics: Membranes; Endoplasmic Reticulum; Ornithine
PubMed: 37685982
DOI: 10.3390/ijms241713174