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ChemMedChem Aug 2020Three photoswitchable tetrapeptides, based on a known synthetic antibacterial, were designed and synthesized to determine activity against Staphylococcus aureus. Each...
Three photoswitchable tetrapeptides, based on a known synthetic antibacterial, were designed and synthesized to determine activity against Staphylococcus aureus. Each peptide contains an azobenzene photoswitch incorporated into either the N-terminal side chain (1), C-terminal side chain (2), or the C-terminus (3) to allow reversible switching between cis- and trans-enriched photostationary states. Biological assays revealed that the C-terminus azobenzene (3) possessed the most potent antibacterial activity, with an MIC of 1 μg/mL. In this study, net positive charge, hydrophobicity, position of the azobenzene, secondary structure, and amphiphilicity were all found to contribute to antibacterial activity, with each of these factors likely facilitating the peptide to disrupt the negatively charged bacterial lipid membrane. Hence, these short photoswitchable antibacterial tetrapeptides provide insights for the future design and synthesis of antibiotics targeting S. aureus.
Topics: Anti-Bacterial Agents; Azo Compounds; Dose-Response Relationship, Drug; Microbial Sensitivity Tests; Molecular Structure; Peptides; Staphylococcus aureus; Structure-Activity Relationship
PubMed: 32558320
DOI: 10.1002/cmdc.202000280 -
Chemistry (Weinheim An Der Bergstrasse,... Nov 2022Molecular switches have been used as delivery vehicles for various molecular and ionic species. The ones that reversibly operate with light are arguably the best... (Review)
Review
Molecular switches have been used as delivery vehicles for various molecular and ionic species. The ones that reversibly operate with light are arguably the best candidates for the purpose as they can be operated using light. The two states of these photoswitchable systems often possess remarkable differences in terms of their structural features and electronic properties. Photochromic systems with the appropriate embellishment of functionalities at suitable positions have thus been used as photoresponsive receptors. The use of light-driven alterations of the structural features has led to differential molecular recognition with these switchable host molecules. In this article, we discuss the use of such supramolecular systems as the delivery vehicles for ions and molecules that started with the pioneering work by Shinkai back in 1979. This review will explicitly cover the development from 2001 to 2022 with some past background and the future prospects of the field.
Topics: Azo Compounds; Ions
PubMed: 35959934
DOI: 10.1002/chem.202201902 -
The Science of the Total Environment Jun 2022Microbial fuel cells (MFCs) exhibit tremendous potential in the sustainable management of dye wastewater via degrading azo dyes while generating electricity. The past... (Review)
Review
Microbial fuel cells (MFCs) exhibit tremendous potential in the sustainable management of dye wastewater via degrading azo dyes while generating electricity. The past decade has witnessed advances in MFC configurations and materials; however, comprehensive analyses of design and material and its association with dye degradation and electricity generation are required for their industrial application. MFC models with high efficiency of dye decolorization (96-100%) and a wide variation in power generation (29.4-940 mW/m) have been reported. However, only 28 out of 104 studies analyzed dye mineralization - a prerequisite to obviate dye toxicity. Consequently, the current review aims to provide an in-depth analysis of MFCs potential in dye degradation and mineralization and evaluates materials and designs as crucial factors. Also, structural and operation parameters critical to large-scale applicability and complete mineralization of azo dye were evaluated. Choice of materials, i.e., bacteria, anode, cathode, cathode catalyst, membrane, and substrate and their effects on power density and dye decolorization efficiency presented in review will help in economic feasibility and MFCs scalability to develop a self-sustainable solution for treating azo dye wastewater.
Topics: Azo Compounds; Bioelectric Energy Sources; Electricity; Electrodes; Wastewater
PubMed: 35202698
DOI: 10.1016/j.scitotenv.2022.154038 -
Chemistry (Weinheim An Der Bergstrasse,... Feb 2021Light regulation of drug molecules has gained growing interest in biochemical and pharmacological research in recent years. In addition, a serious need for novel...
Light regulation of drug molecules has gained growing interest in biochemical and pharmacological research in recent years. In addition, a serious need for novel molecular targets of antibiotics has emerged presently. Herein, the development of a photocontrollable, azobenzene-based antibiotic precursor towards tryptophan synthase (TS), an essential metabolic multienzyme complex in bacteria, is presented. The compound exhibited moderately strong inhibition of TS in its E configuration and five times lower inhibition strength in its Z configuration. A combination of biochemical, crystallographic, and computational analyses was used to characterize the inhibition mode of this compound. Remarkably, binding of the inhibitor to a hitherto-unconsidered cavity results in an unproductive conformation of TS leading to noncompetitive inhibition of tryptophan production. In conclusion, we created a promising lead compound for combatting bacterial diseases, which targets an essential metabolic enzyme, and whose inhibition strength can be controlled with light.
Topics: Azo Compounds; Enzyme Inhibitors; Tryptophan Synthase
PubMed: 33078454
DOI: 10.1002/chem.202004061 -
Current Protocols in Nucleic Acid... Dec 2020This article contains the detailed biophysical characterization, biological testing, and photo-switching protocols of azobenzene containing siRNAs (siRNAzos), which have...
This article contains the detailed biophysical characterization, biological testing, and photo-switching protocols of azobenzene containing siRNAs (siRNAzos), which have photoswitchable properties that can be controlled with light. First, the siRNAzos are characterized by annealing the sense and anti-sense strands together and then measuring the circular dichroism (CD) profile, and the melting temperatures (T ) of the duplexes. Second, the biological testing of the siRNAzos in cell culture is done to determine their gene silencing efficacy. Finally, their gene-silencing activities are measured after exposure to ultraviolet (UV) light in order to inactivate the siRNAzo, and then broadband visible light, which re-activates the siRNAzo. This inactivation/reactivation protocol can be done in real time, and is reversible and robust and can be performed multiple times on the same sample if desired. © 2020 Wiley Periodicals LLC. Basic Protocol 1: Bio-physical characterization of siRNAzo duplexes Basic Protocol 2: Evaluation of azobenzene gene-silencing using Firefly Luciferase Basic Protocol 3: Evaluation of azobenzene gene-silencing using reverse transcriptase-polymerase chain reaction (RT-PCR).
Topics: Azo Compounds; Gene Silencing; Luciferases, Firefly; RNA, Small Interfering; Reverse Transcriptase Polymerase Chain Reaction
PubMed: 33175468
DOI: 10.1002/cpnc.119 -
Molecules (Basel, Switzerland) Jul 2022The rational design of small building block molecules and understanding their molecular assemblies are of fundamental importance in creating new stimuli-responsive...
The rational design of small building block molecules and understanding their molecular assemblies are of fundamental importance in creating new stimuli-responsive organic architectures with desired shapes and functions. Based on the experimental results of light-induced conformational changes of four types of triangular azo dyes with different terminal functional groups, as well as absorption and fluorescence characteristics associated with their molecular assemblies, we report that aggregation-active emission enhancement (AIEE)-active compound () substituted with sterically crowded -butyl (-Bu) groups showed approximately 35% light-induced molecular switching and had a strong tendency to assemble into highly stable hexagonal structures with AIEE characteristics. Their sizes were regulated from nanometer-scale hexagonal rods to micrometer-scale sticks depending on the concentration. This is in contrast to other triangular compounds with bromo (Br) and triphenylamine (TPA) substituents, which exhibited no photoisomerization and tended to form flexible fibrous structures. Moreover, non-contact exposure of the fluorescent hexagonal nanorods to ultraviolet (UV) light led to a dramatic hexagonal-to-amorphous structure transition. The resulting remarkable variations, such as in the contrast of microscopic images and fluorescence characteristics, were confirmed by various microscopic and spectroscopic measurements.
Topics: Azo Compounds; Fluorescent Dyes; Spectrum Analysis
PubMed: 35889253
DOI: 10.3390/molecules27144380 -
International Journal of... 2023In biological engineering, cell immobilization is a modern technique for immobilizing free cells in a small space. Disintegration and elimination of azo dyes [Reactive...
In biological engineering, cell immobilization is a modern technique for immobilizing free cells in a small space. Disintegration and elimination of azo dyes [Reactive Orange 122 (orange 2RL) and Reactive Red 194 (Reactive Red M-2BF)] were investigated by using sp. and sp. mixed with , respectively. After 7 days of incubation, the maximum decolorization was spotted at 40 ppm for Reactive Orange 122 and 20 ppm for Reactive Red 194 by sp. and sp. mixed with , respectively. The findings revealed that the best decolorization activity was found at pH 11 and 25 °C under aeration conditions. BG11 was considered the best medium for azo dye decolorization with a high decolorization percentage. Additionally, different concentrations of nitrogen and phosphorus show the high activity of decolorization of both dyes. Referring to vitamins (thiamin and Ascorbic acid), all studied concentrations showed high decolorization activity with immobilized sp. mixed with ; however, different concentrations (20, 40, and 60 mg/l) of thiamin showed completely decolorization of Reactive Red 194 after 3 days, and 60 mg/l of ascorbic acid showed completely decolorization of Reactive Orange 122 after 5 days of inoculation. FT-IR and GC-Ms analysis for azo dyes after and before treatment with Immobilization of sp. and sp. mixed with were detected. The natural carrier algae and its consortium combined with a suitable immobilization technique were considered in this study, which is non-toxic, enhanced their bioremediation potential for dyes, and allowed multiple uses of biocatalysts. The novel use of the immobilization and its consortium of algae on the degradation efficiency of azo dyes and studying the effect of physicochemical conditions on decolorization and degradation of azo dyes. Application of immobilization techniques using microalgae could be excellent bioremediation of wastewaters.
Topics: Biodegradation, Environmental; Spectroscopy, Fourier Transform Infrared; Azo Compounds; Coloring Agents; Textiles
PubMed: 35867909
DOI: 10.1080/15226514.2022.2103093 -
International Microbiology : the... May 2020Azo dyes are aromatic compounds with one to many -N=N- groups as well as the leading class of synthetic dyes utilised in commercial solicitations. Azo dyes, released in... (Review)
Review
Azo dyes are aromatic compounds with one to many -N=N- groups as well as the leading class of synthetic dyes utilised in commercial solicitations. Azo dyes, released in the environment through textile effluents, have hazardous effects on the aquatic as well as human life. Their persistence and discharge into the environment are becoming a global concern; thus, the remediation of these contaminants has acquired great attention. The current review comprehensively discusses some of the main aspects of biodegradation of azo dyes. A variety of physicochemical approaches has already been utilised for treatment of textile effluents counting filtration, coagulation and chemical flocculation. Though these conventional techniques are effective, yet they are lavish and also comprise formation of concentrated sludge that makes a secondary disposal problem. In this regard, microbial usage is an effective, economical, bio-friendly and ecologically benign approach.
Topics: Azo Compounds; Bacteria; Biodegradation, Environmental; Fungi; Humans; Industrial Waste; Microalgae; Plants; Water Pollutants, Chemical
PubMed: 31741129
DOI: 10.1007/s10123-019-00103-2 -
Chemosphere Feb 2023In this preset study, porous-cross-linked enzyme aggregates (CLEAs) of Pleurotus ostreatus laccase were utilized for the spontaneous decolorization and detoxification of...
In this preset study, porous-cross-linked enzyme aggregates (CLEAs) of Pleurotus ostreatus laccase were utilized for the spontaneous decolorization and detoxification of triarylmethane and azo dyes, reactive blue 2 (RB) and malachite green (MG). The specific surface area and pore radius of the porous-CLEAs are 136.3 m/g and 19.47 A, and the higher specific surface indicated greater biocatalytic efficiency, as increased mass transfer and dye interaction with the CLEAs laccase. CLEAs laccase decolorized 500 ppm of MG and RB with 98.12-58.33% efficiency after 120 min, at pH 5.0 and 50°C, without a mediator. Furthermore, the biotransformation of the MG and RB with immobilized laccase was confirmed with the help of UV-visible spectroscopy, high-performance liquid chromatography, and Fourier transform infrared spectroscopy. The reusability potential of CLEAs was assessed in batch mode for 10 cycles of dye decolorization. The decolorization activities for the immobilized laccase were 89% and 12% at the 6th cycle for MG and RB, respectively. This immobilized enzyme could effectively remove dyes from aqueous solution, and demonstrated significant detoxification in experimental plants (Triticum aestivum and Phaseolus mungo) and plant growth-promoting rhizobacteria (Azospirillum brasilense, Bacillus megaterium, Rhizobium leguminosarum, Bacillus subtilis, and Pseudomonas fluorescens). In conclusion, porous CLEAs laccase could be useful as a potential bioremediation tool for the detoxification and decolorization of dyeing wastewater in future.
Topics: Laccase; Pleurotus; Azo Compounds; Porosity; Coloring Agents
PubMed: 36563730
DOI: 10.1016/j.chemosphere.2022.137612 -
Journal of Hazardous Materials Jan 2024Tartrazine (TZ), or E 102 or C Yellow, is a commonly used azo dye in the food and dyeing industries. Its excessive usage beyond permissible levels threatens human health...
Tartrazine (TZ), or E 102 or C Yellow, is a commonly used azo dye in the food and dyeing industries. Its excessive usage beyond permissible levels threatens human health and the aquatic environment. While previous studies have reported adverse effects such as mutagenicity, carcinogenicity, and reproductive toxicity. Our study aimed to comprehensively evaluate the developmental neurotoxicity of TZ exposure via biochemical and behavioral examinations and explored the underlying mechanism via gene expression analyses. TZ at an environmentally relevant concentration (50 mg/L) significantly induces oxidative stress, altered antioxidant (SOD, CAT and GSH) response, triggered cellular damage (MDA and LDH), and induced neuro-biochemical changes (AChE and NO). Gene expression analyses revealed broad disruptions in genes associated with antioxidant defense (sod1, cat, and gstp1), mitochondrial dysfunction (mfn2, opa1, and fis1),evoked inflammatory response (nfkb, tnfa, and il1b), apoptosis activation (bcl2, bax, and p53), and neural development (bdnf, mbp, and syn2a). Behavioral analysis indicated altered thigmotaxis, touch response, and locomotion depending on the concentration of TZ exposure. Remarkably, the observed effective concentrations were consistent with the permitted levels in food products, highlighting the neurodevelopmental effects of TZ at environmentally relevant concentrations. These findings provide valuable insights into the underlying molecular mechanisms, particularly the role of mitochondria-mediated apoptosis, contributing to TZ-induced neurodevelopmental disorders in vivo.
Topics: Animals; Humans; Tartrazine; Antioxidants; Zebrafish; Azo Compounds; Oxidative Stress; Apoptosis; Mitochondria; Embryo, Nonmammalian
PubMed: 37741213
DOI: 10.1016/j.jhazmat.2023.132524