-
Plant Cell Reports Jul 2024MdERF023 is a transcription factor that can reduce salt tolerance by inhibiting ABA signaling and Na/H homeostasis. Salt stress is one of the principal environmental...
MdERF023 is a transcription factor that can reduce salt tolerance by inhibiting ABA signaling and Na/H homeostasis. Salt stress is one of the principal environmental stresses limiting the growth and productivity of apple (Malus × domestica). The APETALA2/ethylene response factor (AP2/ERF) family plays key roles in plant growth and various stress responses; however, the regulatory mechanism involved has not been fully elucidated. In the present study, we identified an AP2/ERF transcription factor (TF), MdERF023, which plays a negative role in apple salt tolerance. Stable overexpression of MdERF023 in apple plants and calli significantly decreased salt tolerance. Biochemical and molecular analyses revealed that MdERF023 directly binds to the promoter of MdMYB44-like, a positive modulator of ABA signaling-mediated salt tolerance, and suppresses its transcription. In addition, MdERF023 downregulated the transcription of MdSOS2 and MdAKT1, thereby reducing the Na expulsion, K absorption, and salt tolerance of apple plants. Taken together, these results suggest that MdERF023 reduces apple salt tolerance by inhibiting ABA signaling and ion transport, and that it could be used as a potential target for breeding new varieties of salt-tolerant apple plants via genetic engineering.
Topics: Malus; Plant Proteins; Abscisic Acid; Gene Expression Regulation, Plant; Transcription Factors; Salt Tolerance; Signal Transduction; Sodium; Plants, Genetically Modified; Promoter Regions, Genetic
PubMed: 38958739
DOI: 10.1007/s00299-024-03272-1 -
Neoplasma Jun 2024Allicin (AL) is one of garlic-derived organosulfides and has a variety of pharmacological effects. Studies have reported that AL has notable inhibitory effects on liver...
Allicin (AL) is one of garlic-derived organosulfides and has a variety of pharmacological effects. Studies have reported that AL has notable inhibitory effects on liver cancer, gastric cancer, breast cancer, and other cancers. However, there are no relevant reports about its role in human nasopharyngeal carcinoma. Ferroptosis is an iron-dependent form of non-apoptotic regulated cell death. Increasing evidence indicates that induction of ferroptosis can inhibit the proliferation, migration, invasion, and survival of various cancer cells, which act as a tumor suppressor in cancer. In this study, we confirmed that AL can inhibit cell proliferation, migration, invasion, and survival in human nasopharyngeal carcinoma cells. Our finding shows that AL can induce the ferroptosis axis by decreasing the level of GSH and GPX4 and promoting the induction of toxic LPO and ROS. AL-mediated cytotoxicity in human nasopharyngeal carcinoma cells is dependent on ferroptosis. Therefore, AL has good anti-cancer properties and is expected to be a potential drug for the treatment of nasopharyngeal carcinoma.
Topics: Humans; Ferroptosis; Disulfides; Nasopharyngeal Carcinoma; Cell Proliferation; Sulfinic Acids; Nasopharyngeal Neoplasms; Cell Line, Tumor; Reactive Oxygen Species; Cell Movement; Phospholipid Hydroperoxide Glutathione Peroxidase; Glutathione; Cell Survival
PubMed: 38958714
DOI: 10.4149/neo_2024_240108N8 -
Acta Crystallographica Section B,... Aug 2024The structures of three multicomponent crystals formed with imidazole-based drugs, namely metronidazole, ketoconazole and miconazole, in conjunction with trithiocyanuric...
The structures of three multicomponent crystals formed with imidazole-based drugs, namely metronidazole, ketoconazole and miconazole, in conjunction with trithiocyanuric acid are characterized. Each of the obtained adducts represents a different category of crystalline molecular forms: a cocrystal, a salt and a cocrystal of salt. The structural analysis revealed that in all cases, the N-H...N hydrogen bond is responsible for the formation of acid-base pairs, regardless of whether proton transfer occurs or not, and these molecular pairs are combined to form unique supramolecular motifs by centrosymmetric N-H...S interactions between acid molecules. The complex intermolecular forces acting in characteristic patterns are discussed from the geometric and energetic perspectives, involving Hirshfeld surface analysis, pairwise energy estimation, and natural bond orbital calculations.
PubMed: 38958685
DOI: 10.1107/S2052520624005055 -
Journal of Chemical Ecology Jul 2024Male orchid bees are unique in the animal kingdom for making perfumes that function as sex pheromone. Males collect volatile chemicals from the environment in the...
Male orchid bees are unique in the animal kingdom for making perfumes that function as sex pheromone. Males collect volatile chemicals from the environment in the neotropical forests, including floral and non-floral sources, creating complex but species-specific blends. Male orchid bees exhibit several adaptations to facilitate perfume collection and storage. When collecting volatile compounds, males apply lipid substances that they secrete from cephalic labial glands onto the fragrant substrate. These lipids help dissolve and retain the volatiles, similar to the process of 'enfleurage' in the traditional perfume industry. We investigated how the chemical composition of acquired perfume and labial gland secretions varied across the phylogeny of orchid bees, including 65 species in five genera from Central and South America. Perfumes showed rapid evolution as revealed by low overall phylogenetic signal, in agreement with the idea that perfume compounds diverge rapidly and substantially among closely related species due to their role in species recognition. A possible exception were perfumes in the genus Eulaema, clustering closely in chemospace, partly mediated by high proportions of carvone and trans-carvone oxide. Labial gland secretions, in contrast, showed a strong phylogenetic signal at the genus level, with secretions of Eufriesea and Exaerete dominated by fatty acids and Eulaema dominated by saturated acetates of chain lengths 12 to 16 C-atoms. Secretions of the majority of Euglossa were heavily dominated by one unsaturated long chain diacetate, (9Z)-Eicosen-1,20-diyldiacetate. However, we also identified few highly divergent species of Euglossa in four subclades (11 species) that appear to have secondarily replaced the diacetate with other compounds. In comparison with environment-derived perfumes, the evolution of labial gland secretion is much slower, likely constrained by the underlying biochemical pathways, but perhaps influenced by perfume-solvent chemical interactions.
PubMed: 38958679
DOI: 10.1007/s10886-024-01514-w -
Journal of Chemical Ecology Jul 2024Characteristics such as calcareous morphology and life cycle are used to understand the ecology of calcified rhodophytes. However, there is limited information regarding... (Review)
Review
Characteristics such as calcareous morphology and life cycle are used to understand the ecology of calcified rhodophytes. However, there is limited information regarding their chemical profiles and biological activities. Therefore, a systematic review (PRISMA) was conducted to assess the influence of the chemistry of calcareous rhodophytes on ecological interactions in the marine environment. The keywords used were: ["Chemical AND [Ecology OR Interaction OR Response OR Defense OR Effect OR Cue OR Mediated OR Induce]"] AND ["Red Seaweed" OR "Red Macroalgae" OR Rhodophy?] AND [Calcified OR Calcareous] in Science Direct, Scielo, PUBMED, Springer, Web of Science, and Scopus. Only English articles within the proposed theme were considered. Due to the low number of articles, another search was conducted with three classes and 16 genera. Finally, 67 articles were considered valid. Their titles, abstracts, and keywords were analyzed using IRaMuTeQ through factorial, hierarchical and similarity classification. Most of the studies used macroalgae thallus to evaluate chemical mediation while few tested crude extracts. Some substances were noted as sesquiterpene (6-hydroxy-isololiolide), fatty acid (heptadeca5,8,11-triene) and dibromomethane. The articles were divided into four classes: Herbivory, Competition, Settlement/Metamorphosis, and Epiphytism. Crustose calcareous algae were associated with studies of Settlement/Metamorphosis, while calcified algae were linked to herbivory. Thus, the importance of chemistry in the ecology of these algae is evident,and additional studies are needed to identify the substances responsible for ecological interactions. This study collected essential information on calcified red algae, whose diversity appears to be highly vulnerable to the harmful impacts of ongoing climate change.
PubMed: 38958678
DOI: 10.1007/s10886-024-01525-7 -
International Journal of Systematic and... Jul 2024Novel Gram-positive, catalase-negative, α-haemolytic cocci were isolated from breast milk samples of healthy mothers living in Hanoi, Vietnam. The 16S rRNA gene...
Novel Gram-positive, catalase-negative, α-haemolytic cocci were isolated from breast milk samples of healthy mothers living in Hanoi, Vietnam. The 16S rRNA gene sequences of these strains varied by 0-2 nucleotide polymorphisms. The 16S rRNA gene sequence of one strain, designated as BME SL 6.1, showed the highest similarity to those of NCTC 8618 (99.4 %), ATCC 49124 (99.4 %), and ATCC 19258 (99.3 %) in the salivarius group. Whole genome sequencing was performed on three selected strains. Phylogeny based on 631 core genes clustered the three strains into the salivarius group, and the strains were clearly distinct from the other species in this group. The average nucleotide identity (ANI) value of strain BME SL 6.1 exhibited the highest identity with NCTC 8618 (88.4 %), followed by ATCC 49124 (88.3 %) and ATCC 19258 (87.4 %). The ANI and digital DNA-DNA hybridization values between strain BME SL 6.1 and other species were below the cut-off value (95 and 70 %, respectively), indicating that it represents a novel species of the genus . The strains were able to produce α-galactosidase and acid from raffinose and melibiose. Therefore, we propose to assign the strains to a new species of the genus as sp. nov. The type strain is BME SL 6.1 (=VTCC 12812=NBRC 116368).
Topics: RNA, Ribosomal, 16S; Phylogeny; Humans; Female; DNA, Bacterial; Milk, Human; Streptococcus; Sequence Analysis, DNA; Nucleic Acid Hybridization; Bacterial Typing Techniques; Vietnam; Whole Genome Sequencing
PubMed: 38958657
DOI: 10.1099/ijsem.0.006442 -
ACS Applied Materials & Interfaces Jul 2024Hydrogels, as flexible materials, have been widely used in the field of flexible sensors. Human sweat contains a variety of biomarkers that can reflect the physiological...
Hydrogels, as flexible materials, have been widely used in the field of flexible sensors. Human sweat contains a variety of biomarkers that can reflect the physiological state of the human body. Therefore, it is of great practical significance and application value to realize the detection of sweat composition and combine it with human motion sensing through a hydrogel. Based on mussel-inspired chemistry, polydopamine (PDA) and gold nanoparticles (AuNPs) were coated on the surface of cellulose nanocrystals (CNCs) to obtain CNC-based nanocomposites (CNCs@PDA-Au), which could simultaneously enhance the mechanical, electrochemical, and self-healing properties of hydrogels. The CNCs@PDA-Au was composited with poly(vinyl alcohol) (PVA) hydrogel to obtain the nanocomposite hydrogel (PVA/CNCs@PDA-Au) by freeze-thaw cycles. The PVA/CNCs@PDA-Au has excellent mechanical strength (7.2 MPa) and self-healing properties (88.3%). The motion sensors designed with PVA/CNCs@PDA-Au exhibited a fast response time (122.9 ms), wide strain sensing range (0-600.0%), excellent stability, and fatigue resistance. With the unique electrochemical redox properties of uric acid, the designed hydrogel sensor successfully realized the detection of uric acid in sweat with a wide detection range (1.0-100.0 μmol/L) and low detection limit (0.42 μmol/L). In this study, the dual detection of human motion and uric acid in sweat was successfully realized by the designed PVA/CNCs@PDA-Au nanocomposite hydrogel.
PubMed: 38958653
DOI: 10.1021/acsami.4c07717 -
International Journal of Systematic and... Jul 2024A novel slightly halophilic, aerobic, and Gram-stain-negative strain, designated as CH-27, was isolated during a bacterial resource investigation of intertidal sediment...
A novel slightly halophilic, aerobic, and Gram-stain-negative strain, designated as CH-27, was isolated during a bacterial resource investigation of intertidal sediment collected from Xiaoshi Island in Weihai, PR China. Cells of strain CH-27 were rod-shaped with widths of 0.3-0.6 µm and lengths of 2.0-11.0 µm. Strain CH-27 grew optimally at 37 °C, pH 7.0 and with 2.0 % (w/v) NaCl. Catalase activity was weakly positive and oxidase activity was positive. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CH-27 was most related to KCTC 92639 (93.6 %), followed by MCCC 1K00261 (92.0 %). Based on genome comparisons between strain CH-27 and KCTC 92639, the average amino acid identity was 63.6 % and the percentage of conserved proteins was 48.3 %. The major cellular fatty acid of strain CH-27 (≥10 %) was iso-C and the sole respiratory quinone was quinone-8. The polar lipids were phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, and aminophospholipid. The DNA G+C content was 62.7 mol%. Based on comprehensive analysis of its phylogenetic, physiological, biochemical, and chemotaxonomic characteristics, strain CH-27 represents a novel species in a novel genus, for which the name gen. nov., sp.nov. is proposed. The type strain is CH-27 (=MCCC 1H00480=KCTC 8011).
Topics: Base Composition; Phylogeny; Fatty Acids; Geologic Sediments; China; RNA, Ribosomal, 16S; DNA, Bacterial; Bacterial Typing Techniques; Sequence Analysis, DNA; Genome, Bacterial; Phospholipids
PubMed: 38958649
DOI: 10.1099/ijsem.0.006440 -
Chembiochem : a European Journal of... Jul 2024Genetic Code Expansion technology offers significant potential in incorporating noncanonical amino acids into proteins at precise locations, allowing for the modulation...
Genetic Code Expansion technology offers significant potential in incorporating noncanonical amino acids into proteins at precise locations, allowing for the modulation of protein structures and functions. However, this technology is often limited by the need for costly and challenging-to-synthesize external noncanonical amino acid sources. In this study, we address this limitation by developing autonomous cells capable of biosynthesizing halogenated tryptophan derivatives and introducing them into proteins using Genetic Code Expansion technology. By utilizing inexpensive halide salts and different halogenases, we successfully achieve the selective biosynthesis of 6-chloro-tryptophan, 7-chloro-tryptophan, 6-bromo-tryptophan, and 7-bromo-tryptophan. These derivatives are introduced at specific positions with corresponding bioorthogonal aminoacyl-tRNA synthetase/tRNA pairs in response to the amber codon. Following optimization, we demonstrate the robust expression of proteins containing halogenated tryptophan residues in cells with the ability to biosynthesize these tryptophan derivatives. This study establishes a versatile platform for engineering proteins with various halogenated tryptophans.
PubMed: 38958600
DOI: 10.1002/cbic.202400366 -
Journal of Chemical Theory and... Jul 2024Self-splicing ribozymes are small ribonucleic acid (RNA) enzymes that catalyze their own cleavage through a transphosphoesterification reaction. While this process is...
Self-splicing ribozymes are small ribonucleic acid (RNA) enzymes that catalyze their own cleavage through a transphosphoesterification reaction. While this process is involved in some specific steps of viral RNA replication and splicing, it is also of importance in the context of the (putative) first autocatalytic RNA-based systems that could have preceded the emergence of modern life. The uncatalyzed phosphoester bond formation is thermodynamically very unfavorable, and many experimental studies have focused on understanding the molecular features of catalysis in these ribozymes. However, chemical reaction paths are short-lived and not easily characterized by experimental approaches, so molecular simulation approaches appear as an ideal tool to unveil the molecular details of the reaction. Here, we focus on the model hairpin ribozyme. We show that identifying a relevant initial conformation for reactivity studies, which is frequently overlooked in mixed quantum-classical studies that predominantly concentrate on the chemical reaction itself, can be highly challenging. These challenges stem from limitations in both available experimental structures (which are chemically altered to prevent self-cleavage) and the accuracy of force fields, together with the necessity for comprehensive sampling. We show that molecular dynamics simulations, combined with extensive conformational phase space exploration with Hamiltonian replica-exchange simulations, enable us to characterize the relevant conformational basins of the minimal hairpin ribozyme in the ligated state prior to self-cleavage. We find that what is usually considered a canonical reactive conformation with active site geometries and hydrogen-bond patterns that are optimal for the addition-elimination reaction with general acid/general base catalysis is metastable and only marginally populated. The thermodynamically stable conformation appears to be consistent with the expectations of a mechanism that does not require the direct participation of ribozyme residues in the reaction. While these observations may suffer from forcefield inaccuracies, all investigated forcefields lead to the same conclusions upon proper sampling, contrasting with previous investigations on shorter timescales suggesting that at least one reparametrization of the Amber99 forcefield allowed to stabilize aligned active site conformations. Our study demonstrates that identifying the most pertinent reactant state conformation holds equal importance alongside the accurate determination of the thermodynamics and kinetics of the chemical steps of the reaction.
PubMed: 38958594
DOI: 10.1021/acs.jctc.4c00294