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Wireless portable bioelectronic nose device for multiplex monitoring toward food freshness/spoilage.Biosensors & Bioelectronics Nov 2022Monitoring food freshness/spoilage is important to ensure food quality and safety. Current methods of food quality monitoring are mostly time-consuming and labor...
Monitoring food freshness/spoilage is important to ensure food quality and safety. Current methods of food quality monitoring are mostly time-consuming and labor intensive processes that require massive analytical equipment. In this study, we developed a portable bioelectronic nose (BE-nose) integrated with trace amine-associated receptor (TAAR) nanodiscs (NDs), allowing food quality monitoring via the detection of food spoilage indicators, including the biogenic amines cadaverine (CV) and putrescine (PT). The olfactory receptors TAAR13c and TAAR13d, which have specific affinities for CV and PT, were produced and successfully reconstituted in ND structures. TAAR13 NDs BE-nose-based side-gated field-effect transistor (SG-FET) system was constructed by utilizing a graphene micropattern (GM) into which two types of olfactory NDs (TAAR13c ND and TAAR13d ND) were introduced, and this system showed ultrahigh sensitivity for a limit of detection (LOD) of 1 fM for CV and PT. Moreover, the binding affinities between the TAAR13 NDs and the indicators were confirmed by a tryptophan fluorescence quenching assay and biosimulations, in which the specific binding site was confirmed. Gas-phase indicators were detected by the TAAR13 NDs BE-nose platform, and the LODs for CV and PT were confirmed to be 26.48 and 7.29 ppb, respectively. In addition, TAAR13 NDs BE-nose was fabricated with commercial gas sensors as a portable platform for the measurement of NH and HS, multiplexed monitoring was achieved with similar performance, and the change ratio of the indicators was observed in a real sample. The integration of commercial gas sensors on a BE-nose enhanced the accuracy and reliability for the quality monitoring of real food samples. These results indicate that the portable TAAR13 NDs BE-nose can be used to monitor CV and PT over a wide range of concentrations, therefore, the electronic nose platform can be utilized for monitoring the freshness/spoilage step in various foods.
Topics: Biosensing Techniques; Cadaverine; Electronic Nose; Putrescine; Receptors, Odorant; Reproducibility of Results
PubMed: 35839622
DOI: 10.1016/j.bios.2022.114551 -
Journal of the American Chemical Society Dec 2019The enantioselective, vicinal diamination of alkenes represents one of the stereocontrolled additions that remains an outstanding challenge in organic synthesis. A...
The enantioselective, vicinal diamination of alkenes represents one of the stereocontrolled additions that remains an outstanding challenge in organic synthesis. A general solution to this problem would enable the efficient and selective preparation of widely useful, enantioenriched diamines for applications in medicinal chemistry and catalysis. In this article, we describe the first enantioselective, diamination of simple alkenes mediated by a chiral, enantioenriched organoselenium catalyst together with a bistosyl urea as the bifunctional nucleophile and fluorocollidinium tetrafluoroborate as the stoichiometric oxidant. Diaryl, aryl-alkyl, and alkyl-alkyl olefins bearing a variety of substituents are all diaminated in consistently high enantioselectivities but variable yields. The reaction likely proceeds through a Se(II)/Se(IV) redox catalytic cycle reminiscent of the dichlorination reported previously. Furthermore, the -stereospecificity of the transformation shows promise for highly enantioselective diaminations of alkenes with no strong steric or electronic bias.
Topics: Alkenes; Amination; Catalysis; Diamines; Organoselenium Compounds; Oxidants; Oxidation-Reduction; Stereoisomerism; Urea
PubMed: 31742399
DOI: 10.1021/jacs.9b11261 -
Current Medicinal Chemistry 2020The discovery of cisplatin and the subsequent research revealed the importance of dinitrogen-containing moiety for the anticancer action of metal complexes. Moreover,...
BACKGROUND
The discovery of cisplatin and the subsequent research revealed the importance of dinitrogen-containing moiety for the anticancer action of metal complexes. Moreover, certain diamine ligands alone display cytotoxicity that contributes to the overall activity of corresponding complexes.
OBJECTIVE
To summarize the current knowledge on the anticancer efficacy, selectivity, and the mechanisms of action of metal complexes with various types of diamine ligands.
METHODS
The contribution of aliphatic acyclic, aliphatic cyclic, and aromatic diamine ligands to the anticancer activity and selectivity/toxicity of metal complexes with different metal ions were analyzed by comparison with organic ligand alone and/or conventional platinum-based chemotherapeutics.
RESULTS
The aliphatic acyclic diamine ligands are present mostly in complexes with platinum. Aliphatic cyclic diamines are part of Pt(II), Ru(II) and Au(III) complexes, while aromatic diamine ligands are found in Pt(II), Ru(II), Pd(II) and Ir(III) complexes. The type and oxidation state of metal ions greatly influences the cytotoxicity of metal complexes with aliphatic acyclic diamine ligands. Lipophilicity of organic ligands, dependent on alkyl-side chain length and structure, determines their cellular uptake, with edda and eddp/eddip ligands being most useful in this regard. Aliphatic cyclic diamine ligands improved the activity/toxicity ratio of oxaliplatin-type complexes. The complexes with aromatic diamine ligands remain unexplored regarding their anticancer mechanism. The investigated complexes mainly caused apoptotic or necrotic cell death.
CONCLUSION
Metal complexes with diamine ligands are promising candidates for efficient and more selective alternatives to conventional platinum-based chemotherapeutics. Further research is required to reveal the chemico-physical properties and molecular mechanisms underlying their biological activity.
Topics: Antineoplastic Agents; Cisplatin; Coordination Complexes; Diamines; Ligands
PubMed: 30378486
DOI: 10.2174/0929867325666181031114306 -
Advances in Applied Microbiology 2021l-lysine is an essential amino acid that contains various functional groups including α-amino, ω-amino, and α-carboxyl groups, exhibiting high reaction potential. The... (Review)
Review
l-lysine is an essential amino acid that contains various functional groups including α-amino, ω-amino, and α-carboxyl groups, exhibiting high reaction potential. The derivatization of these functional groups produces a series of value-added chemicals, such as cadaverine, glutarate, and d-lysine, that are widely applied in the chemical synthesis, cosmetics, food, and pharmaceutical industries. Here, we review recent advances in the biotechnological production of l-lysine and its derivatives and expatiate key technological strategies. Furthermore, we also discuss the existing challenges and potential strategies for more efficient production of these chemicals.
Topics: Biotechnology; Cadaverine; Glutarates; Lysine
PubMed: 34140131
DOI: 10.1016/bs.aambs.2021.02.001 -
Nature Communications Oct 2019The 1,2-diamine motif is widely present in natural products, pharmaceutical compounds, and catalysts used in asymmetric synthesis. The simultaneous introduction of two...
The 1,2-diamine motif is widely present in natural products, pharmaceutical compounds, and catalysts used in asymmetric synthesis. The simultaneous introduction of two amino groups across an alkene feedstock is an appealing yet challenging approach for the synthesis of 1,2-diamines, primarily due to the inhibitory effect of the diamine products to transition metal catalysts and the difficulty in controlling reaction diastereoselectivity and regioselectivity. Herein we report a scalable electrocatalytic 1,2-diamination reaction that can be used to convert stable, easily available aryl alkenes and sulfamides to 1,2-diamines with excellent diastereoselectivity. Monosubstituted sulfamides react in a regioselective manner to afford 1,2-diamines bearing different substituents on the two amino groups. The combination of an organic redox catalyst and electricity not only obviates the use of any transition metal catalyst and oxidizing reagent, but also ensures broad reaction compatibility with a variety of electronically and sterically diverse substrates.
PubMed: 31672991
DOI: 10.1038/s41467-019-13024-5 -
Physical Review Letters Feb 2021The interaction between proteins and hydration water stabilizes protein structure and promotes functional dynamics, with water translational motions enabling protein...
The interaction between proteins and hydration water stabilizes protein structure and promotes functional dynamics, with water translational motions enabling protein flexibility. Engineered solvent-free protein-polymer hybrids have been shown to preserve protein structure, function, and dynamics. Here, we used neutron scattering, protein and polymer perdeuteration, and molecular dynamics simulations to explore how a polymer dynamically replaces water. Even though relaxation rates and vibrational properties are strongly modified in polymer coated compared to hydrated proteins, liquidlike polymer dynamics appear to plasticize the conjugated protein in a qualitatively similar way as do hydration-water translational motions.
Topics: Diamines; Glycolates; Hydrogen Bonding; Molecular Dynamics Simulation; Myoglobin; Neutron Diffraction; Polyethylene Glycols; Polymers; Protein Conformation; Proteins; Thermodynamics; Water
PubMed: 33709739
DOI: 10.1103/PhysRevLett.126.088102 -
World Journal of Microbiology &... Oct 2022The consumption of foods fraught with histamine can lead to various allergy-like symptoms if the histamine is not sufficiently degraded in the human body. The... (Review)
Review
The consumption of foods fraught with histamine can lead to various allergy-like symptoms if the histamine is not sufficiently degraded in the human body. The degradation occurs primarily in the small intestine, naturally catalyzed by the human diamine oxidase (DAO). An inherent or acquired deficiency in human DAO function causes the accumulation of histamine and subsequent intrusion of histamine into the bloodstream. The histamine exerts its effects acting on different histamine receptors all over the body but also directly in the intestinal lumen. The inability to degrade sufficient amounts of dietary histamine is known as the 'histamine intolerance'. It would be preferable to solve this problem initially by the production of histamine-free or -reduced foods and by the oral supplementation of exogenous DAO supporting the human DAO in the small intestine. For the latter, DAOs from mammalian, herbal and microbial sources may be applicable. Microbial DAOs seem to be the most promising choice due to their possibility of an efficient biotechnological production in suitable microbial hosts. However, their biochemical properties, such as activity and stability under process conditions and substrate selectivity, play important roles for their successful application. This review deals with the advances and challenges of DAOs and other histamine-oxidizing enzymes for their potential application as processing aids for the production of histamine-reduced foods or as orally administered adjuvants to humans who have been eating food fraught with histamine.
Topics: Amine Oxidase (Copper-Containing); Animals; Diamines; Histamine; Humans; Mammals; Oxidation-Reduction; Receptors, Histamine
PubMed: 36208352
DOI: 10.1007/s11274-022-03421-2 -
Angewandte Chemie (International Ed. in... Oct 2022Cytochrome P450s and Galactose Oxidases exploit redox active ligands to form reactive high valent intermediates for oxidation reactions. This strategy works well for the...
Cytochrome P450s and Galactose Oxidases exploit redox active ligands to form reactive high valent intermediates for oxidation reactions. This strategy works well for the late 3d metals where accessing high valent states is rather challenging. Herein, we report the oxidation of Ni (salen) (salen=N,N'-bis(3,5-di-tert-butyl-salicylidene)-1,2-cyclohexane-(1R,2R)-diamine) with mCPBA (meta-chloroperoxybenzoic acid) to form a fleeting Ni bisphenoxyl diradical species, in CH CN and CH Cl at -40 °C. Electrochemical and spectroscopic analyses using UV/Vis, EPR, and resonance Raman spectroscopies revealed oxidation events both on the ligand and the metal centre to yield a Ni bisphenoxyl diradical species. DFT calculations found the electronic structure of the ligand and the d-configuration of the metal center to be consistent with a Ni bisphenoxyl diradical species. This three electron oxidized species can perform hydrogen atom abstraction and oxygen atom transfer reactions.
Topics: Chlorobenzoates; Cyclohexanes; Cytochromes; Diamines; Ethylenediamines; Galactose; Galactose Oxidase; Hydrogen; Ligands; Metals; Nickel; Oxidation-Reduction; Oxygen
PubMed: 35978531
DOI: 10.1002/anie.202211345 -
Canadian Journal of Veterinary Research... Jan 2022The objective of this study was to describe the histological and histochemical characteristics of the lacrimal glands of beluga whales. The study was carried out on the...
The objective of this study was to describe the histological and histochemical characteristics of the lacrimal glands of beluga whales. The study was carried out on the formalin-fixed ocular globes from 96 carcasses of beluga whales found stranded in the St. Lawrence estuary in Quebec, Canada. Hematoxylin and eosin (H&E) stained slides from the eyes of each whale were examined for lacrimal glands. Histological description was done with H&E and Masson Trichrome (MT) stains. Period Acid-Schiff (PAS), Alcian blue (AB) pH 1.0 and 2.5, and High Iron Diamine (HID) stains were used for histochemical characterization of glycoproteins. Thirteen ocular samples from animals ranging from neonate to 48 y included sections of lacrimal glands. The H&E stain revealed a tubuloalveolar gland architecture, separated into lobules by dense connective tissue. Each lobule contained a mixture of acini and tubules with ductules. Small and large acini were composed of low and tall columnar cells, respectively. Acinar cells contained basophilic cytoplasmic granules. The ductules were lined with a bi-layered cuboidal-to-squamous epithelium. The MT stain highlighted the connective tissue separating ductules and acini. Large acini were positive for PAS and some small acini had patchy uptake. Positive staining for AB pH 1.0 and 2.5 was mainly seen in tall columnar cells as compared to small acini that had faint to no stain uptake. High Iron Diamine stain revealed 90% staining of all acinar cells, with 10% exhibiting a mixed blue-black tinge. It was concluded that the lacrimal glands of beluga whales have similar histological and histochemical findings to those of artiodactyla and carnivora orders.
Topics: Animals; Beluga Whale; Coloring Agents; Diamines; Iron; Lacrimal Apparatus
PubMed: 34975225
DOI: No ID Found -
European Journal of Medicinal Chemistry Nov 2022N,6-Substituted 1,3,5-triazine-2,4-diamines (N-substituted guanamines) attracted significant interest due to their potential in the development of bioactive molecules.... (Review)
Review
N,6-Substituted 1,3,5-triazine-2,4-diamines (N-substituted guanamines) attracted significant interest due to their potential in the development of bioactive molecules. With just two points of diversity, this scaffold is proved to be suitable for constructing compounds targeting various enzymes, receptors, transporters, and nucleic acids with an array of therapeutic applications, particularly in cancer, inflammation, and CNS disorders. This review discusses progress in the synthesis of N,6-substituted 1,3,5-triazine-2,4-diamines and their biological activities ranging from the inhibition of cancer-related enzymes (e.g. DNA topoisomerase IIα, carbonic anhydrases, ubiquitin-conjugating enzyme 2B, lysophosphatidic acid acyltransferase β and various kinases) to the binding to CNS-relevant receptors (e.g. histamine H, serotonin 5-HT, adenosine A, and α7 nicotinic acetylcholine receptors).
Topics: Diamines; Triazines; alpha7 Nicotinic Acetylcholine Receptor
PubMed: 35981459
DOI: 10.1016/j.ejmech.2022.114645