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1.
Protein Sci ; 33(9): e5146, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39150147

ABSTRACT

D2 is a structural and cooperative domain of Thermotoga maritima Arginine Binding Protein, that possesses a remarkable conformational stability, with a denaturation temperature of 102.6°C, at pH 7.4. The addition of potassium thiocyanate causes a significant decrease in the D2 denaturation temperature. The interactions of thiocyanate ions with D2 have been studied by means of isothermal titration calorimetry measurements and molecular dynamics simulations. It emerged that: (a) 20-30 thiocyanate ions interact with the D2 surface and are present in its first solvation shell; (b) each of them makes several contacts with protein groups, both polar and nonpolar ones. The addition of guanidinium thiocyanate causes a marked destabilization of the D2 native state, because both the ions are denaturing agents. However, on adding to the solution containing D2 and guanidinium thiocyanate a stabilizing agent, such as TMAO, sucrose or sodium sulfate, a significant increase in denaturation temperature occurs. The present results confirm that counteraction is a general phenomenon for globular proteins.


Subject(s)
Molecular Dynamics Simulation , Protein Stability , Thermotoga maritima , Thiocyanates , Thiocyanates/chemistry , Thermotoga maritima/chemistry , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Protein Denaturation/drug effects , Sulfates/chemistry , Methylamines/chemistry , Protein Domains , Guanidines/chemistry
2.
PLoS One ; 19(8): e0306259, 2024.
Article in English | MEDLINE | ID: mdl-39141636

ABSTRACT

The antibacterial oxidative response, which relies on the production of hydrogen peroxide (H2O2) and hypothiocyanite (OSCN-), is a major line of defense protecting the human airway epithelium (HAE) from lesions when infected. The in vitro studies of the oxidative responses are performed mainly by one-shot H2O2 exposure that does not recapitulate the complex H2O2/LPO/SCN- system releasing the reactive oxygen species in airway secretions. A cell-free in vitro assay mimicking this system has been described but was not fully characterized. Here, we comprehensively characterized the hourly H2O2/OSCN- concentrations produced within this in vitro assay and assessed the resistance of Pseudomonas aeruginosa and Staphylococcus aureus clinical strains to the HAE oxidative response. We found that H2O2/OSCN- were steadily produced from 7h and up to 25h, but OSCN- was detoxified in 15 minutes by bacteria upon exposure. Preliminary tests on PA14 showed survival rates at 1-hour post-exposure (hpe) to H2O2 of roughly 50% for 105 and 107 colony-forming unit (CFU)/mL inocula, while 102 and 104 CFU/mL inocula were cleared after one hpe. Thirteen clinical strains were then exposed, highlighting that conversely to P. aeruginosa, S. aureus showed resistance to oxidative stress independently of its antibiotic resistance phenotype. Our results demonstrated how this in vitro assay can be helpful in assessing whether pathogens can resist the antibacterial oxidative HAE response. We anticipate these findings as a starting point for more sophisticated in vitro models that could serve as high-throughput screening for molecules targeting the bacterial antioxidant response.


Subject(s)
Hydrogen Peroxide , Oxidative Stress , Pseudomonas aeruginosa , Staphylococcus aureus , Pseudomonas aeruginosa/metabolism , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/metabolism , Humans , Hydrogen Peroxide/metabolism , Respiratory Mucosa/microbiology , Respiratory Mucosa/metabolism , Oxidation-Reduction , Anti-Bacterial Agents/pharmacology , Drug Resistance, Bacterial , Pseudomonas Infections/microbiology , Pseudomonas Infections/metabolism , Thiocyanates
3.
Int J Mol Sci ; 25(16)2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39201750

ABSTRACT

By introducing disordered molecules into a crystal structure, the motion of the disordered molecules easily induces the formation of multidimensional frameworks in functional crystal materials, allowing for structural phase transitions and the realization of various dielectric properties within a certain temperature range. Here, we prepared a novel ionic complex [C7H8N3]3[Fe(NCS)6]·H2O (1) between 2-aminobenzimidazole and ferric isothiocyanate from ferric chloride hexahydrate, ammonium thiocyanate, and 2-aminobenzimidazole using the evaporation of the solvent method. The main components, the single-crystal structure, and the thermal and dielectric properties of the complex were characterized using infrared spectroscopy, elemental analysis, single-crystal X-ray diffraction, powder XRD, thermogravimetric analysis, differential scanning calorimetry, variable-temperature and variable-frequency dielectric constant tests, etc. The analysis results indicated that compound 1 belongs to the P21/n space group. Within the crystal structure, the [Fe(NCS)6]3- anion formed a two-dimensional hydrogen-bonded network with the organic cation through S···S interactions and hydrogen bonding. The disorder-order motion of the anions and cations within the crystal and the deformation of the crystal frameworks lead to a significant reversible isostructural phase transition and multiaxial dielectric anomalies of compound 1 at approximately 240 K.


Subject(s)
Benzimidazoles , Phase Transition , Thiocyanates , Thiocyanates/chemistry , Benzimidazoles/chemistry , Crystallography, X-Ray , Iron/chemistry , Hydrogen Bonding , Models, Molecular , Calorimetry, Differential Scanning , Thermogravimetry , X-Ray Diffraction
4.
Nutrients ; 16(16)2024 Aug 11.
Article in English | MEDLINE | ID: mdl-39203795

ABSTRACT

BACKGROUND: Perchlorate, nitrate, and thiocyanate are widely recognized as endocrine disrupting chemicals, which are closely related to thyroid function. Animal and human studies show a correlation between thyroid hormone and bone mineral density (BMD). However, it remains unknown whether perchlorate, nitrate, and thiocyanate were associated with BMD. This study aimed to explore the association between perchlorate, nitrate, and thiocyanate exposure with BMD. METHOD: A cross-sectional analysis among 5607 participants from the 2011-2018 National Health and Nutrition Examination Survey (NHANES) was conducted in the present study. Perchlorate, nitrate, and thiocyanate were detected in urine by ion chromatography. Survey-weighted generalized linear regression, restricted cubic splines, and qgcomp models were used to assess the association of BMDs with single and mixed perchlorate, nitrate, and thiocyanate exposures. In addition, age, gender, and BMI stratified these associations. RESULTS: Negative associations were found between perchlorate and nitrate with BMDs. Furthermore, based on the qgcomp model results, the combined association of perchlorate, nitrate, and thiocyanate exposure was negatively associated with BMDs (ß = -0.017, 95% CI: -0.041, -0.024 for total BMD; ß = -0.017, 95% CI: -0.029, -0.005 for lumbar BMD). Additionally, there was a significant effect after gender, age, and BMI stratification between perchlorate, nitrate, and thiocyanate with BMDs in the normal weight group (ß = -0.015, 95% CI: -0.020, -0.011 for total BMD; ß = -0.022, 95% CI: -0.028, -0.016 for lumbar BMD) and children and adolescents group (ß = -0.025, 95% CI: -0.031, -0.019 for total BMD; ß -0.017, 95% CI: -0.029, -0.005 for lumbar BMD). CONCLUSIONS: The present study indicated a negative correlation between BMDs and urinary perchlorate, nitrate, and thiocyanate levels, with nitrate being the main contributor to the mixture effect. People with normal weight and children and adolescents were more likely to be affected.


Subject(s)
Bone Density , Nitrates , Nutrition Surveys , Perchlorates , Thiocyanates , Humans , Thiocyanates/urine , Perchlorates/urine , Female , Male , Nitrates/urine , Cross-Sectional Studies , Adult , Middle Aged , United States , Young Adult , Adolescent , Child , Aged , Environmental Exposure/adverse effects
5.
Water Res ; 265: 122268, 2024 Nov 01.
Article in English | MEDLINE | ID: mdl-39173358

ABSTRACT

The coupled process of anammox and reduced-sulfur driven autotrophic denitrification can simultaneously remove nitrogen and sulfur from wastewater, while minimizing energy consumption and sludge production. However, the research on the coupled process for removing naturally toxic thiocyanate (SCN-) is limited. This work successfully established and operated a one-stage coupled system by co-cultivating mature anammox and SCN--driven autotrophic denitrification sludge in a single reactor. In this one-stage coupled system, the average total nitrogen removal efficiency was 89.68±3.33 %, surpassing that of solo anammox (81.80±2.10 %) and SCN--driven autotrophic denitrification (85.20±1.54 %). Moreover, the average removal efficiency of SCN- reached 99.50±3.64 %, exceeding that of solo SCN--driven autotrophic denitrification (98.80±0.65 %). The results of the 15N stable isotope tracer labeling experiment revealed the respective reaction rates of anammox and denitrification as 106.38±10.37 µmol/L/h and 69.07±8.07 µmol/L/h. By analyzing metagenomic sequencing data, Thiobacillus_denitrificans was identified as the primary contributor to SCN- degradation in this coupled system. Furthermore, based on the comprehensive analysis of nitrogen and sulfur metabolic pathways, as well as the genes associated with SCN- degradation, it can be inferred that the cyanate (CNO) pathway was responsible for SCN- degradation. This work provided a deeper insight into coupling anammox with SCN--driven autotrophic denitrification in a one-stage coupled system, thereby contributing to the development of an effective approach for wastewater treatment involving both SCN- and nitrogen.


Subject(s)
Autotrophic Processes , Denitrification , Nitrogen , Thiocyanates , Thiocyanates/metabolism , Nitrogen/metabolism , Bioreactors , Wastewater/chemistry , Waste Disposal, Fluid/methods , Sewage , Oxidation-Reduction , Anaerobiosis
6.
Biochemistry ; 63(14): 1752-1760, 2024 Jul 16.
Article in English | MEDLINE | ID: mdl-38967549

ABSTRACT

The wildtype H-Ras protein functions as a molecular switch in a variety of cell signaling pathways, and mutations to key residues result in a constitutively active oncoprotein. However, there is some debate regarding the mechanism of the intrinsic GTPase activity of H-Ras. It has been hypothesized that ordered water molecules are coordinated at the active site by Q61, a highly transforming amino acid site, and Y32, a position that has not previously been investigated. Here, we examine the electrostatic contribution of the Y32 position to GTP hydrolysis by comparing the rate of GTP hydrolysis of Y32X mutants to the vibrational energy shift of each mutation measured by a nearby thiocyanate vibrational probe to estimate changes in the electrostatic environment caused by changes at the Y32 position. We further compared vibrational energy shifts for each mutation to the hydration potential of the respective side chain and demonstrated that Y32 is less critical for recruiting water molecules into the active site to promote hydrolysis than Q61. Our results show a clear interplay between a steric contribution from Y32 and an electrostatic contribution from Q61 that are both critical for intrinsic GTP hydrolysis.


Subject(s)
Guanosine Triphosphate , Static Electricity , Thiocyanates , Hydrolysis , Thiocyanates/chemistry , Thiocyanates/metabolism , Guanosine Triphosphate/metabolism , Guanosine Triphosphate/chemistry , Humans , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/chemistry , Proto-Oncogene Proteins p21(ras)/metabolism , Tyrosine/chemistry , Tyrosine/metabolism , Tyrosine/genetics , Mutation , Catalytic Domain , Water/chemistry , Water/metabolism , Models, Molecular
7.
J Bacteriol ; 206(8): e0009824, 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39016617

ABSTRACT

The innate immune system employs a variety of antimicrobial oxidants to control and kill host-associated bacteria. Hypothiocyanite/hypothiocyanous acid (-OSCN/HOSCN) is one such antimicrobial oxidant that is synthesized by lactoperoxidase, myeloperoxidase, and eosinophil peroxidase at sites throughout the human body. HOSCN has potent antibacterial activity while being largely non-toxic toward human cells. The molecular mechanisms by which bacteria sense and defend themselves against HOSCN have only recently begun to be elaborated, notably by the discovery of bacterial HOSCN reductase (RclA), an HOSCN-degrading enzyme widely conserved among bacteria that live on epithelial surfaces. In this paper, I show that Ni2+ sensitizes Escherichia coli to HOSCN by inhibiting glutathione reductase and that inorganic polyphosphate protects E. coli against this effect, probably by chelating Ni2+ ions. I also found that RclA is very sensitive to inhibition by Cu2+ and Zn2+, metals that are accumulated to high levels by innate immune cells, and that, surprisingly, thioredoxin and thioredoxin reductase are not involved in HOSCN stress resistance in E. coli. These results advance our understanding of the contribution of different oxidative stress responses and redox buffering pathways to HOSCN resistance in E. coli and illustrate important interactions between metal ions and the enzymes bacteria use to defend themselves against oxidative stress. IMPORTANCE: Hypothiocyanite (HOSCN) is an antimicrobial oxidant produced by the innate immune system. The molecular mechanisms by which host-associated bacteria defend themselves against HOSCN have only recently begun to be understood. The results in this paper are significant because they show that the low molecular weight thiol glutathione and enzyme glutathione reductase are critical components of the Escherichia coli HOSCN response, working by a mechanism distinct from that of the HOSCN-specific defenses provided by the RclA, RclB, and RclC proteins and that metal ions (including nickel, copper, and zinc) may impact the ability of bacteria to resist HOSCN by inhibiting specific defensive enzymes (e.g., glutathione reductase or RclA).


Subject(s)
Escherichia coli , Thiocyanates , Escherichia coli/genetics , Escherichia coli/drug effects , Escherichia coli/metabolism , Thiocyanates/pharmacology , Thiocyanates/metabolism , Nickel/pharmacology , Nickel/metabolism , Escherichia coli Proteins/metabolism , Escherichia coli Proteins/genetics , Drug Resistance, Bacterial , Glutathione Reductase/metabolism , Glutathione Reductase/genetics , Anti-Bacterial Agents/pharmacology , Zinc/metabolism , Zinc/pharmacology , Copper/metabolism , Copper/pharmacology
8.
J AOAC Int ; 107(5): 876-883, 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-38964347

ABSTRACT

BACKGROUND: Glucosinolates (GSLs) are the most controversial yet ignored class of phytochemicals. These are the middleman phytochemicals that have low bioactivity. But once there is any injury in the plant-manmade, insect caused, or natural-magic happens. The compound is broken down into smaller phytochemicals referred to as glucosinolate hydrolytic products (GHPs; nitriles, isothiocyanates [ITCs], and thiocyanates). These hydrolytic products are like a showstopper of the fashion industry. These compounds have some of the highest bioactivity in nature. They have been associated with a varied range of bioactivities (anticancer, antioxidant, insecticidal, weedicide, etc.) by researchers across the globe. OBJECTIVE: The objective of the current article is to provide a critical review to highlight some of the important bioactivities of these ignored compounds and for promoting researchers to at least give these compounds a chance-to glow in the dark. METHODS: This review has been written from analysis of accessible literature, mostly from the last 5 years (2018-2023), with some critically essential exceptions. RESULTS: The review highlighted a brief background of GSLs and its hydrolysis. Efforts were made to include most of the biological properties of the compound. Special emphasis has been given to the anticancer activities of the compound with details of the involved mechanism. CONCLUSIONS: Considering the wide array of bioactivities of GHPs, it is essential to consider it as a prospective medicinal compound. More GHPs-in a similar manner as sulforaphane-can be proceeded to phase trials. HIGHLIGHTS: The mechanistic pathway for production of GHPs and related biological activities have been discussed in detail. The bioactivities have been further explained using the involved mechanism.


Subject(s)
Glucosinolates , Isothiocyanates , Glucosinolates/chemistry , Glucosinolates/analysis , Hydrolysis , Isothiocyanates/chemistry , Isothiocyanates/pharmacology , Humans , Antioxidants/pharmacology , Antioxidants/chemistry , Thiocyanates/chemistry , Nitriles/chemistry , Nitriles/pharmacology , Animals , Phytochemicals/pharmacology , Phytochemicals/chemistry , Phytochemicals/analysis , Insecticides/chemistry , Insecticides/pharmacology
10.
Methods Mol Biol ; 2833: 145-152, 2024.
Article in English | MEDLINE | ID: mdl-38949708

ABSTRACT

Mycobacterium tuberculosis is an infectious pathogen that requires biosafety level-3 laboratory for handling. The risk of transmission is high to laboratory staff, and to manage the organism safely, it is necessary to construct high containment laboratory facilities at great expense. This limits the application of tuberculosis diagnostics to areas where there is insufficient capital to invest in laboratory infrastructure. In this method, we describe a process of inactivating sputum samples by either heat or guanidine thiocyanate (GTC) that renders them safe without affecting the quantification of viable bacteria. This method eliminates the need for level 3 containment laboratory for the tuberculosis molecular bacterial load assay (TB-MBLA) and is applicable in low- and middle-income countries.


Subject(s)
Containment of Biohazards , Mycobacterium tuberculosis , Sputum , Thiocyanates , Mycobacterium tuberculosis/isolation & purification , Humans , Containment of Biohazards/methods , Sputum/microbiology , Bacterial Load/methods , Tuberculosis/diagnosis , Tuberculosis/microbiology , Tuberculosis/prevention & control , Guanidines , Hot Temperature , Microbial Viability
11.
J Pharm Biomed Anal ; 248: 116317, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-38936170

ABSTRACT

An instrumental-free, high-throughput assay has been developed for the quantification of thiocyanate in human saliva. The proposed green method is based on the rapid reaction of the analyte with Fe(III) under acidic pH in a microplates format to form a colored complex that is captured as an image by an overhead book scanner. Optimization included the effects of the amount concentration of Fe(III), acidity and reaction time / complex stability using a total volume of 300 µL per well. Validation towards the matrix effect was focused on the specific application and was performed using both artificial and human saliva. The linearity of the developed assay was up to 500 µM thiocyanate offering a lower limit of quantification (LLOQ) of 30 µM. The green potentials were evaluated by both the Green Analytical Procedure (GAPI) and Blue Applicability Grade (BAGI) indexes. The thiocyanate content in the saliva of non-smoking volunteers ranged between 750 and 1350 µΜ, while elevated concentrations were verified in smoking individuals (1860-3080 µΜ). Statistical agreement with a corroborative method was assessed using the Bland-Altman plot.


Subject(s)
High-Throughput Screening Assays , Saliva , Thiocyanates , Thiocyanates/analysis , Saliva/chemistry , Humans , High-Throughput Screening Assays/methods , High-Throughput Screening Assays/instrumentation , Limit of Detection , Green Chemistry Technology/methods , Hydrogen-Ion Concentration , Smoking
12.
J Comput Chem ; 45(26): 2214-2231, 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-38795315

ABSTRACT

According to the Hofmeister series, thiocyanate is the strongest "salting in" anion. In fact, it has a strong denaturant activity against the native state of globular proteins. A molecular level rationalization of the Hofmeister series is still missing, and therefore the denaturant activity of thiocyanate also awaits a robust explanation. In the last years, different types of experimental studies have shown that thiocyanate is capable to directly interact with both polar and nonpolar groups of polypeptide chains. This finding has been scrutinized via a careful computational procedure based on density functional theory approaches. The results indicate that thiocyanate is able to make H-bonds via both the nitrogen and sulfur atom, and to make strong van der Waals interactions with almost all the groups of polypeptide chains, regardless of their polarity.


Subject(s)
Peptides , Thiocyanates , Thiocyanates/chemistry , Peptides/chemistry , Density Functional Theory , Hydrogen Bonding
13.
Biosensors (Basel) ; 14(5)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38785697

ABSTRACT

The surfactant cetyltrimethylammonium bromide (CTAB) induces the aggregation of gold nanoclusters (GNCs), leading to the development of a proposed fluorometric technique for detecting thiocyanate (SCN-) ions based on an anti-aggregation mechanism. This approach is straightforward to execute, highly sensitive, and selective. A significant quenching effect occurs in fluorescence upon using the aggregation agent CTAB in GNCs synthesis, resulting in a transition from intense red fluorescence to dim red. The decrease in fluorescence intensity of GNCs in the presence of CTAB is caused by the mechanism of fluorescence quenching mediated by aggregation. As the levels of SCN- rise, the fluorescence of CTAB-GNCs increases; this may be detected using spectrofluorometry or by visually inspecting under UV irradiation. The recovery of red fluorescence of CTAB-GNCs in the presence of SCN- enables the precise and discerning identification of SCN- within the concentration range of 2.86-140 nM. The minimum detectable concentration of the SCN- ions was 1 nM. The selectivity of CTAB-GNCs towards SCN- ions was investigated compared to other ions, and it was demonstrated that CTAB-GNCs exhibit exceptional selectivity. Furthermore, we believe that CTAB-GNCs have novel possibilities as favorable sensor candidates for various industrial applications. Our detection technique was validated by analyzing SCN- ions in milk samples, which yielded promising results.


Subject(s)
Cetrimonium , Gold , Metal Nanoparticles , Thiocyanates , Gold/chemistry , Metal Nanoparticles/chemistry , Cetrimonium/chemistry , Spectrometry, Fluorescence , Food Industry , Biosensing Techniques , Ions
14.
Environ Sci Pollut Res Int ; 31(23): 34459-34472, 2024 May.
Article in English | MEDLINE | ID: mdl-38703319

ABSTRACT

Associations of perchlorate, thiocyanate, and nitrate exposures with bone mineral density (BMD) in adults have not previously been studied. This study aimed to estimate the associations of individual and concurrent exposure of the three chemicals with adult BMD. Based on National Health and Nutrition Examination Survey (NHANES, 2011-2018), 1618 non-pregnant adults (age ≥ 20 years and 47.0% female) were included in this study. Survey-weighted linear regression models were used to estimate individual urinary perchlorate, thiocyanate, and nitrate concentrations with lumbar spine BMD and total BMD in adults. Then, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) models were conducted to evaluate associations of co-occurrence of the three chemicals with adult BMD. In all participants, nitrate exposure was inversely associated with lumbar spine BMD (ß = - 0.054, 95%CI: - 0.097, - 0.010). In stratification analyses, significant inverse associations were observed in female and participants older than 40 years old. In WQS regressions, significant negative associations of the weighted sum of the three chemicals with total and lumbar spine BMD (ß = - 0.014, 95%CI: - 0.021, - 0.007; ß = - 0.011, 95%CI: - 0.019, - 0.004, respectively) were found, and the dominant contributor was nitrate. In the BKMR models, non-linear dose-response associations of nitrate exposure with lumbar spine and total BMD were observed. These findings suggested that environmental perchlorate, thiocyanate, and nitrate exposure may reduce adult BMD and nitrate is the main contributor.


Subject(s)
Bone Density , Environmental Exposure , Nitrates , Perchlorates , Thiocyanates , Humans , Thiocyanates/urine , Perchlorates/urine , Cross-Sectional Studies , Adult , Female , Nitrates/analysis , Male , Bone Density/drug effects , Middle Aged , Nutrition Surveys , United States , Young Adult
15.
Forensic Toxicol ; 42(2): 221-231, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38739353

ABSTRACT

PURPOSE: Forensic verification of cyanide (CN) poisoning by direct CN analysis in postmortem blood is challenging due to instability of CN in biological samples. CN metabolites, thiocyanate (SCN-) and 2-aminothiazoline-4-carboxylic acid (ATCA), have been proposed as more stable biomarkers, yet it is unclear if either is appropriate for this purpose. In this study, we evaluated the behavior of CN biomarkers in postmortem swine and postmortem blood to determine which serves as the best biomarker of CN exposure. METHODS: CN, SCN-, and ATCA were measured in postmortem swine (N = 8) stored at 4 °C and postmortem blood stored at 25 °C (room temperature, RT) and 37 °C (typical human body temperature, HBT). RESULTS: Following CN poisoning, the concentration of each CN biomarker increased well above the baseline. In postmortem swine, CN concentrations declined rapidly (t1/2 = 34.3 h) versus SCN- (t1/2 = 359 h, 15 days) and ATCA (t1/2 = 544 h, 23 days). CN instability in postmortem blood increased at RT (t1/2 = 10.7 h) and HBT (t1/2 = 6.6 h). SCN- and ATCA were more stable than CN at all storage conditions. In postmortem swine, the t1/2s of SCN- and ATCA were 15 and 23 days, respectively. While both the t1/2s of SCN- and ATCA were relatively lengthy, endogenous levels of SCN- were much more variable than ATCA. CONCLUSION: While there are still questions to be answered, ATCA was the most adept forensic marker of CN poisoning (i.e., ATCA produced the longest half-life, the largest increase above baseline levels, and most stable background concentrations).


Subject(s)
Biomarkers , Cyanides , Animals , Cyanides/poisoning , Cyanides/blood , Biomarkers/blood , Swine , Thiocyanates/poisoning , Thiocyanates/blood , Thiocyanates/metabolism , Forensic Toxicology/methods , Models, Animal , Temperature , Specimen Handling/methods , Thiazoles
16.
Ecotoxicol Environ Saf ; 276: 116307, 2024 May.
Article in English | MEDLINE | ID: mdl-38593497

ABSTRACT

In recent decades, there has been increasing interest in elucidating the role of sulfur-containing compounds in plant metabolism, particularly emphasizing their function as signaling molecules. Among these, thiocyanate (SCN-), a compound imbued with sulfur and nitrogen, has emerged as a significant environmental contaminant frequently detected in irrigation water. This compound is known for its potential to adversely impact plant growth and agricultural yield. Although adopting exogenous SCN- as a nitrogen source in plant cells has been the subject of thorough investigation, the fate of sulfur resulting from the assimilation of exogenous SCN- has not been fully explored. There is burgeoning curiosity in probing the fate of SCN- within plant systems, especially considering the possible generation of the gaseous signaling molecule, hydrogen sulfide (H2S) during the metabolism of SCN-. Notably, the endogenous synthesis of H2S occurs predominantly within chloroplasts, the cytosol, and mitochondria. In contrast, the production of H2S following the assimilation of exogenous SCN- is explicitly confined to chloroplasts and mitochondria. This phenomenon indicates complex interplay and communication among various subcellular organelles, influencing signal transduction and other vital physiological processes. This review, augmented by a small-scale experimental study, endeavors to provide insights into the functional characteristics of H2S signaling in plants subjected to SCN--stress. Furthermore, a comparative analysis of the occurrence and trajectory of endogenous H2S and H2S derived from SCN--assimilation within plant organisms was performed, providing a focused lens for a comprehensive examination of the multifaceted roles of H2S in rice plants. By delving into these dimensions, our objective is to enhance the understanding of the regulatory mechanisms employed by the gasotransmitter H2S in plant adaptations and responses to SCN--stress, yielding invaluable insights into strategies for plant resilience and adaptive capabilities.


Subject(s)
Hydrogen Sulfide , Plants , Signal Transduction , Thiocyanates , Hydrogen Sulfide/metabolism , Thiocyanates/metabolism , Plants/metabolism , Gasotransmitters/metabolism , Chloroplasts/metabolism , Inactivation, Metabolic
17.
Methods Mol Biol ; 2787: 201-207, 2024.
Article in English | MEDLINE | ID: mdl-38656491

ABSTRACT

Ribonucleic Acid (RNA) isolation is a basic technique in the field of molecular biology. The purpose of RNA isolation is to acquire pure and complete RNA that can be used to evaluate gene expression. Many methods can be used to perform RNA isolation, all of them based on the chemical properties of nucleic acids. However, some of them do not achieve high RNA yields and purity levels when used in a number of marginally studied crops of agronomic importance, such as grain and vegetable amaranth plants. In the method described here, the use of guanidinium thiocyanate and two additional precipitation steps with different reagents designed to obtain high yields and RNA purity levels from diverse plant species employed for plant functional genomics studies is described.


Subject(s)
Crops, Agricultural , RNA, Plant , Crops, Agricultural/genetics , RNA, Plant/isolation & purification , RNA, Plant/genetics , Thiocyanates/chemistry , Guanidines/chemistry , Amaranthus/genetics , Amaranthus/chemistry
18.
J Biol Chem ; 300(5): 107282, 2024 May.
Article in English | MEDLINE | ID: mdl-38604564

ABSTRACT

The major human pathogen Streptococcus pneumoniae encounters the immune-derived oxidant hypothiocyanous acid (HOSCN) at sites of colonization and infection. We recently identified the pneumococcal hypothiocyanous acid reductase (Har), a member of the flavoprotein disulfide reductase enzyme family, and showed that it contributes to the HOSCN tolerance of S. pneumoniae in vitro. Here, we demonstrate in mouse models of pneumococcal infection that Har is critical for colonization and invasion. In a colonization model, bacterial load was attenuated dramatically in the nasopharynx when har was deleted in S. pneumoniae. The Δhar strain was also less virulent compared to wild type in an invasion model as reflected by a significant reduction in bacteria in the lungs and no dissemination to the blood and brain. Kinetic measurements with recombinant Har demonstrated that this enzyme reduced HOSCN with near diffusion-limited catalytic efficiency, using either NADH (kcat/KM = 1.2 × 108 M-1s-1) or NADPH (kcat/KM = 2.5 × 107 M-1s-1) as electron donors. We determined the X-ray crystal structure of Har in complex with the FAD cofactor to 1.50 Å resolution, highlighting the active site architecture characteristic for this class of enzymes. Collectively, our results demonstrate that pneumococcal Har is a highly efficient HOSCN reductase, enabling survival against oxidative host immune defenses. In addition, we provide structural insights that may aid the design of Har inhibitors.


Subject(s)
Bacterial Proteins , Pneumococcal Infections , Streptococcus pneumoniae , Streptococcus pneumoniae/enzymology , Animals , Mice , Pneumococcal Infections/microbiology , Pneumococcal Infections/enzymology , Pneumococcal Infections/immunology , Bacterial Proteins/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Crystallography, X-Ray , Humans , Female , Oxidoreductases Acting on CH-CH Group Donors/metabolism , Oxidoreductases Acting on CH-CH Group Donors/genetics , Thiocyanates
19.
Free Radic Biol Med ; 219: 104-111, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38608822

ABSTRACT

Hypothiocyanous acid (HOSCN) is an endogenous oxidant produced by peroxidase oxidation of thiocyanate (SCN-), an ubiquitous sulfur-containing pseudohalide synthesized from cyanide. HOSCN serves as a potent microbicidal agent against pathogenic bacteria, viruses, and fungi, functioning through thiol-targeting mechanisms, independent of currently approved antimicrobials. Additionally, SCN- reacts with hypochlorous acid (HOCl), a highly reactive oxidant produced by myeloperoxidase (MPO) at sites of inflammation, also producing HOSCN. This imparts both antioxidant and antimicrobial potential to SCN-. In this review, we discuss roles of HOSCN/SCN- in immunity and potential therapeutic implications for combating infections.


Subject(s)
Anti-Infective Agents , Thiocyanates , Animals , Humans , Anti-Infective Agents/pharmacology , Anti-Infective Agents/therapeutic use , Anti-Infective Agents/chemistry , Antioxidants/pharmacology , Antioxidants/therapeutic use , Hypochlorous Acid/metabolism , Hypochlorous Acid/therapeutic use , Hypochlorous Acid/chemistry , Oxidation-Reduction , Peroxidase/metabolism , Respiratory Tract Infections/drug therapy , Respiratory Tract Infections/microbiology , Thiocyanates/therapeutic use , Thiocyanates/chemistry , Thiocyanates/pharmacology , Thiocyanates/metabolism
20.
Environ Res ; 252(Pt 2): 118833, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38599446

ABSTRACT

Thiocyanate (SCN-), a non-volatile inorganic pollutant, is commonly found in various types of industrial wastewater, which is resistant to hydrolysis and has the potential to be toxic to organisms. Premagnetized iron-copper-carbon ternary micro-electrolytic filler (pre-Fe/Cu/C) was prepared to degrade SCN-. Pre-Fe/Cu/C exhibited the most significant enhancement effect on SCN- removal when magnetized for 5 min with an intensity of 100 mT, and the SCN- removal rate was the highest at an initial pH of 3.0 and an aeration rate of 1.6 L/min. The electrochemical corrosion and electron transfer in the pre-Fe/Cu/C system were confirmed through SEM, XPS, FTIR, XRD, and electrochemical tests. This resulted in the formation of more corrosion products and multiple cycles of Fe2+/Fe3+ and Cu0/Cu+/Cu2+. Additionally, density functional theory (DFT) calculations and electron paramagnetic resonance (EPR) were utilized to illustrate the oxygen adsorption properties of the materials and the participation of reactive oxygen species (1O2, ·O2-, and ·OH) in SCN- removal. The degradation products of SCN- were identified as SO42-, HCO3-, NH4+, and N2. This study introduced the use of permanent magnets for the first time to enhance Fe/Cu/C ternary micro-electrolytic fillers, offering a cost-effective, versatile, and stable approach that effectively effectively enhanced the degradation of SCN-.


Subject(s)
Copper , Iron , Thiocyanates , Water Pollutants, Chemical , Thiocyanates/chemistry , Copper/chemistry , Iron/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/analysis , Carbon/chemistry , Corrosion
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