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Considering the frequent detection of pesticides in the aquatic environment, the ecotoxicological effects of Chlorpyrifos (CHP), an organophosphate, and alpha-cypermethrin (ACM), a pyrethroid, on freshwater microalgae were compared for the first time in this study. High concentrations of both CHP and ACM significantly suppressed the growth of test microalga Graesiella emersonii (p < 0.05). The 96-h EC50 of CHP and ACM were 54.42 mg L-1 and 29.40 mg L-1, respectively. Sub-inhibitory doses of both pesticides increased ROS formation in a concentration-dependent manner, which was accompanied by changes in antioxidant enzymes activities, lipid peroxidation, and variations in photosynthetic pigment concentration. Furthermore, both pesticides influenced photosystem II performance, oxygen-evolving complex efficiency and, intracellular ATP levels. Scanning electron microscopy analysis revealed that high concentrations of both CHP and ACM caused considerable morphological changes in the microalga. In comparison, CHP was more toxic than ACM at low concentrations, whereas ACM was more toxic at high concentrations.
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Cloropirifos , Plaguicidas , Piretrinas , Cloropirifos/toxicidad , Estrés Oxidativo , Fotosíntesis , Piretrinas/toxicidadRESUMEN
Alpha-cypermethrin, a pyrethroid pesticide, is frequently used on crops to prevent insect attacks. However, occasionally, due to drift, leaching, or with rainwater, it enters the aquatic environment and poses a serious threat to the growth of non-target aquatic organisms. In the current study, we were interested in investigating the damaging effect of alpha-cypermethrin on a local freshwater non-target green alga Chlorella sp. NC-MKM in terms of its protein levels. This was achieved by exposing Chlorella sp. NC-MKM to an EC50 concentration of alpha-cypermethrin for 1 day, followed by the two-dimensional (2-D) gel electrophoresis and MALDI-TOF MS. Fifty-three proteins, which had showed significant differential accumulation (> 1.5 fold, P < 0.05) after exposure to alpha-cypermethrin, were considered as differentially accumulated proteins (DAPs). These DAPs were further divided into several functional categories, and the expressions of each in control and treatment samples were compared. Comparison revealed that alpha-cypermethrin exposure affects the accumulation of proteins related with photosynthesis, stress response, carbohydrate metabolism, signal transduction and transporters, translation, transcription, cell division, lipid metabolism, amino acid and nucleotide biosynthesis, secondary metabolites production, and post-translational modification, and thus rendered the tested algal isolate sensitive toward this pesticide. The overall findings of this research thus offer a fundamental understanding of the possible mechanism of action of the insecticide alpha-cypermethrin on the microalga Chlorella sp. NC-MKM and also suggest potential biomarkers for the investigation of pesticide exposed microalgae.
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Chlorella , Microalgas , Plaguicidas , Piretrinas , Chlorella/metabolismo , Microalgas/metabolismo , Proteómica , Piretrinas/toxicidad , Piretrinas/metabolismo , Plaguicidas/metabolismoRESUMEN
Objective: To assess the quality of sleep among patients with schizophrenia.Methods: A cross-sectional descriptive study was conducted with 100 outpatients with schizophrenia recruited from a tertiary care center in Northern India from July 2022 to December 2022. Eligible participants were required to complete a demographic form, the Pittsburgh Sleep Quality Index (PSQI), and the Insomnia Severity Index (ISI). The severity of psychosis was assessed with the Positive and Negative Syndrome Scale (PANSS).Results: The mean age of the participants was 38.87 years (SD = 10.564). The prevalence of poor sleep quality (PSQI ≥ 5) among the patients with schizophrenia was 78%, and the mean PSQI score was 11.2 (SD = 5.31). Most of the participants in whom the prevalence of poor sleep quality was marginally higher were female (51%). Of the 7 PSQI components, daytime dysfunction was more affected (49%) compared to the other 6 components. There was a positive correlation between PSQI and ISI scores (r = 0.805, P < .001). PSQI (U = 380, P < .001) and ISI scores (U = 517, P < .001) were significantly lower in schizophrenia patients taking benzodiazepines. The PANSS scores were not significantly correlated with PSQI or ISI scores.Conclusions: Most patients with schizophrenia suffered significantly from poor sleep quality. The results showed the deleterious impact of poor sleep on their daytime functioning, suggesting the need for comprehensive management of sleep problems in such patients.Prim Care Companion CNS Disord 2023;25(6):23m03564. Author affiliations are listed at the end of this article.
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Esquizofrenia , Sulfonamidas , Humanos , Femenino , Adulto , Masculino , Esquizofrenia/complicaciones , Esquizofrenia/epidemiología , Calidad del Sueño , Centros de Atención Terciaria , Estudios Transversales , Pacientes Ambulatorios , India/epidemiologíaRESUMEN
Objective: To find sexual dysfunction in acute-phase bipolar depression patients and subsequently characterize the gender-wise differences in sexual functioning. Materials and Methods: A cross-sectional, descriptive, observational, purposeful, and hospital-based study was done with 45 patients (age range: 18-59 years) with moderate to severe acute phase bipolar depression (HAM-D scores >18). The domain-wise (Pleasure, Desire/Frequency Desire/Interest, Arousal/Excitement, and Orgasm/Completion) sexual functioning was assessed by the Change in Sexual Functioning Questionnaire (CSFQ-14) (≤41 for females, ≤47 for males as a cut-off for dysfunction). This study is registered in the CTRI (Clinical Trials Registry India, Number: CTRI-2021-07-035182). Results: The prevalence of sexual dysfunction was 91% of bipolar disorder patients with more male participants (53.3%) compared to females (46.7%). The mean HAM-D score for the study sample was 27.93 ± 8.035. The female gender had more dysfunctional scores in desire/frequency (t = 2.229, P = 0.031), desire/interest (t = 2.448, P = 0.019), orgasm/completion (t = 2.974, P = 0.005), and overall total CSFQ (t = 2.946, P = 0.005). The odds of sexual dysfunction were significant given a one-unit increase in suicidal ideation in the index episode (adjusted OR = 1.222, 95% CI: 1.004-1.488, P = .049). Conclusion: Acute-phase bipolar patients have very high sexual dysfunction rates. Females have both global and specific sexual response cycle deficits in comparison to acute phase bipolar depressed males. Future trials shall amuse neurobiology grounded, more individualistic sexual rehabilitation-based interventional paradigms, and longitudinal research models in acute phase bipolar depression.
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In the current study, the effect of the EC50 and LC90 concentrations of pyrethroid insecticide alpha-cypermethrin to cyanobacteria Anabaena sp. NC-K1 was investigated at different time exposures (1st day, 4th day and 7th day) with reference to growth, photosynthetic pigments, oxidative damage and antioxidant defence system. Superoxide dismutase (1.38-fold), peroxidase (5.04) and proline content (2.27-fold) were enhanced compared to the control. After performing 2D gel electrophoresis at 1st day EC50 exposure, where appropriate differences in the biochemical and physiological parameters were observed, 22 differentially accumulated proteins (20 upregulated and 2 downregulated) were selected for mass spectrometry. Out of 42 proteins identified, 20 upregulated protein spots were classified into twelve categories according to their metabolic functions. Proteins related to photosynthesis (phycobilisome rod-core linker polypeptide, rubisco), stress responses (Hsp70, Hsp40, catalase family peroxidase), translation (elongation factor Tu) and amino acid biosynthesis and metabolism (3-phosphoshikimate 1-carboxyvinyl transferase) were significantly upregulated. Additionally, proteins involved in transcription and DNA repair (Snf-2 histone linker phd ring helicase, RNA polymerase sigma factor RpoD and Holliday junction ATP-dependent DNA helicase RuvA) were considerably upregulated. Upregulation of these proteins against pesticide stress presumably maintained the photosynthesis, energy metabolism, carbohydrate metabolism, transport and signalling proteins, transcription, translation and DNA repair. Additionally, these proteins might involve in sufficient detoxification of ROS and play a crucial role in damage removal and repair of oxidized proteins, lipids and nucleic acids. Taken together, Anabaena sp. NC-K1 responded towards alpha-cypermethrin stress via modulating its proteome to maintain its cellular metabolism and homeostasis.
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Anabaena , Cianobacterias , Piretrinas , Anabaena/metabolismo , Fotosíntesis , Proteómica/métodos , Piretrinas/metabolismoRESUMEN
Rheumatoid Arthritis (RA) is a form of arthritis characterized by joint pain, stiffness, swelling and deformity. There has been plethora of researches in the area of rheumatoid arthritis which focused on immune system, genetic predisposition and newer treatment modalities. Researchers have also examined the cognitive decline, physical deficits and their interrelationship in patients with RA. Among several psychological aspects depression, anxiety and stress emerge as significant psychological co morbidity. RA is a multifactorial, chronic, inflammatory disease primarily affects physical functioning as well as psychological aspects. Pain, fatigue, duration of disease, disease activity and functional disability are very common in rheumatoid arthritis which is leading cause of psychological distress and functional disability. Various types of neuropsychological battery were used to assess the decline in specific areas like attention, executive functioning, visuo-spatial learning, verbal learning/memory etc. These functions were compared with other type of arthritis disease. Also, various other factors like depression, cardiovascular diseases, other systemic and chronic disease and concomitant drugs intake etc. also affected cognitive functioning in Rheumatoid Arthritis patients. The objective of this review was to identify and explore the rates and types of cognitive impairment in RA. This present review paper systematically examines and summarizes the cognition related decrement in arthritis patients. Multiple research articles between 1990 to 2018 were searched. These reviews were evaluated and synthesized using a narrative and descriptive approach.
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Rheumatoid arthritis (RA) is a chronic, painful and debilitating musculoskeletal condition with depression being its common co-morbidity. It is associated with symptoms of fatigue, pain, and sleep disturbances that can overlap with or mimic symptoms of depression. It may occur with at least mild severity is up to 42% of RA patients. Basically, depression refers to a constellation of experience including not only mood but also physical, mental and behavioral experiences. The fact that rates of depression are higher in samples of patients with RA than in the normal population is well documented. The present study was conducted in order to examine the effect of depression on attentional functioning with diagnosed RA patients. Twenty RA patients out of which 10 patients with depression and 10 patients without depression participated in the study. The Beck Depression Inventory was administered for the assessment of depression and the attentional network task was used to measure the attentional performance of the RA patients. Results revealed that there was a significant difference in depressive symptoms among RA patients on accuracy and reaction time (P < 0.01) and orienting effect (P < 0.05). The findings would also imply intervention and rehabilitation of depression among RA patients.
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Alpha-cypermethrin (ACy) is a synthetic pyrethroid insecticide commonly used in agricultural practices for controlling a broad range of insect pests particularly belonging to the order Lepidoptera and Coleoptera. The present study aims to evaluate the toxic effect of ACy on microalgae by studying its influence on Chlorella sp. According to our knowledge, this is the first detailed study of ACy toxicity on microalgae. Significant growth inhibition of Chlorella sp. was observed at high ACy concentration (6-48â¯mgâ¯L-1) during the entire 96â¯h bioassay. The 96â¯h median effective concentration (EC50) of ACy was estimated to be 11.00â¯mgâ¯L-1. Flow cytometry analysis showed an enhanced generation of reactive oxygen species (ROS) and intracellular lipid accumulation after 96â¯h exposure to 11.00â¯mgâ¯L-1 of ACy. Further, the same ACy concentration showed a significant decrease in photosynthetic pigment content and an increase in antioxidant enzyme activity and malondialdehyde (MDA) content in Chlorella sp.
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Chlorella/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Piretrinas/toxicidad , Relación Dosis-Respuesta a Droga , Piretrinas/administración & dosificación , Especies Reactivas de Oxígeno/metabolismoRESUMEN
OBJECTIVE: Liverworts possess historical adaptive strategies for abiotic stresses because they were the first plants that shifted from water to land. Proteomics is a state-of-the-art technique that can capture snapshots of events occurring at the protein level in many organisms. Herein, we highlight the comparison and optimization of an effective protein extraction and precipitation protocol for two-dimensional gel electrophoresis (2-DE) of liverworts. RESULTS: We compared three different protein extraction methods, i.e.,1.5 M Tris-HCl (pH 8.8), 50 mM Tris-HCl (pH 7.5), and polyvinylpolypyrrolidone (PVPP) extraction, followed by three precipitation methods, i.e., 80% ethanol, 80% acetone, and 20% tricholoroacetic acid (TCA)-acetone, in a liverwort Dumortiera hirsuta. Among these methods, 50 mM Tris-HCl (pH 7.5) extraction, followed by 20% TCA-acetone precipitation, appeared to be more suitable for 2-DE. Furthermore, we performed modifications during protein washing, re-solubilization in rehydration buffer and isoelectric focusing (IEF). The modifications provided us better results in terms of protein yield, resolution, spot numbers, and intensities for 2-DE gels of D. hirsuta and other two liverworts, i.e., Marchantia paleacea and Plagiochasma appendiculatum. Furthermore, we randomly selected spots from the 2-DE gel of D. hirsuta and identified using mass spectrometry, which confirms the applicability of this protocol for liverworts proteomics.
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Electroforesis en Gel Bidimensional/métodos , Hepatophyta/metabolismo , Proteínas de Plantas/aislamiento & purificación , Ecosistema , Células Germinativas de las Plantas/metabolismoRESUMEN
In the present study, a combination of phytohormones (indole acetic acid and kinetin) was augmented in nitrogen-limited medium to achieve higher biomass and lipid yield in Graesiella emersonii NC-M1 and Chlorophyta sp. NC-M5. This condition was recorded with a 2.3- and 2.5-fold increase in biomass and lipid yield for Graesiella emersonii NC-M1 compared to the nitrogen-limited condition. Also, this condition showed a 1.6- and 1.08-fold increase in lipid yield and neutral lipid compared to the standard condition. Phytohormones addition also reduced oxidative damage caused by nitrogen-limitation and enhanced monounsaturated fatty acid content. Further, a 5.2- and 3.17-fold enhance in expression level of GPAT and DGAT genes were noticed under nitrogen-limited medium supplemented with phytohormones compared to control.
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Microalgas , Biocombustibles , Biomasa , Diacilglicerol O-Acetiltransferasa , Ácidos Grasos , Glicerol , Ácidos Indolacéticos , Cinetina , Lípidos , Nitrógeno , FosfatosRESUMEN
The effects of iron (Fe), zinc (Zn), and molybdenum (Mo) on the biomass yield, lipid content, lipid yield, and fatty acid composition of Chlorella sp. NC-MKM, Graesiella emersonii NC-M1, Scenedesmus acutus NC-M2, and Chlorophyta sp. NC-M5 were studied. Among them, G. emersonii NC-M1 recorded the highest percentage increase in lipid content (140.3%) and neutral lipid (50.9%) under Zn-supplemented condition compared to the control. Also, it showed a 105% and 41.88% increase in lipid yield and neutral lipid under Fe-supplemented condition compared to the control. However, Chlorella sp. NC-MKM recorded an elevation in lipid yield (70.3% rise) and neutral lipid (24.32% rise) compared to the control in Mo-supplemented condition. The enhanced production of reactive oxygen species (ROS) and antioxidant enzyme (SOD and POD) under Fe-, Zn-, and Mo-supplemented condition supports the lipid accumulation. FAME analysis showed that the overall percentage of SFA and MUFA increased after the addition of Fe, Zn, and Mo in a culture medium compared to the control which is vital for a good-quality biodiesel. Further, biodiesel properties derived from FAMEs such as CN, SV, IV, CFPP, OS, υ, ρ, and HHV were found in accordance with biodiesel standard.
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Hierro/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Microalgas/efectos de los fármacos , Molibdeno/farmacología , Zinc/farmacología , Biocombustibles , Chlorella/efectos de los fármacos , Chlorella/metabolismo , Chlorophyta/efectos de los fármacos , Chlorophyta/metabolismo , Medios de Cultivo/química , Medios de Cultivo/farmacología , Ácidos Grasos/análisis , Lípidos/química , Microalgas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Scenedesmus/efectos de los fármacos , Scenedesmus/metabolismoRESUMEN
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
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Biomass and lipid yield under nutrient depleted and supplemented conditions of N and Mg in two freshwater isolates, Chlorella sp. NC-MKM and Scenedesmus acutus NC-M2 from Meghalaya were investigated for biodiesel production. Both the strains, Chlorella sp. NC-MKM and Scenedesmus acutus NC-M2 are oleaginous in nature having lipid content of 40.2 ± 1.4 and 37.3 ± 2.6% DCW, respectively. The significant increase (92.8%) in lipid content was found in N-depleted condition while an increase (46.65%) in biomass yield was observed under Mg-supplemented condition in Chlorella sp. NC-MKM. Studying the interactive effects of nutrient depletion and supplementation, combination of N-depleted and Mg-supplemented condition was selected for further investigation to check enhanced lipid yield in Chlorella sp. NC-MKM. The results showed a significant increase in biomass yield, lipid yield and lipid content (30, 66.8, and 28.66%, respectively). Under this condition, accumulation of neutral lipid was also enhanced (47.17% M2 gated cells) compared to control (21.37% M2 gated cells). Further, FAMEs revealed that the relative percentage of saturated and mono-unsaturated fatty acids increased (66.16%) in Chlorella sp. NC-MKM compared to control that improves biodiesel properties.
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Peroxiredoxins (Prxs) are vital regulators of intracellular reactive oxygen species levels in all living organisms. Their activity depends on one or two catalytically active cysteine residues, the peroxidatic Cys (CP) and, if present, the resolving Cys (CR). A detailed catalytic cycle has been derived for typical 2-Cys Prxs, however, little is known about the catalytic cycle of 1-Cys Prxs. We have characterized Prx6 from the cyanobacterium Anabaena sp. strain PCC7120 (AnPrx6) and found that in addition to the expected peroxidase activity, AnPrx6 can act as a molecular chaperone in its dimeric state, contrary to other Prxs. The AnPrx6 crystal structure at 2.3 Å resolution reveals different active site conformations in each monomer of the asymmetric obligate homo-dimer. Molecular dynamic simulations support the observed structural plasticity. A FSH motif, conserved in 1-Cys Prxs, precedes the active site PxxxTxxCp signature and might contribute to the 1-Cys Prx reaction cycle.
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Anabaena/metabolismo , Chaperonas Moleculares/metabolismo , Peroxiredoxina VI/química , Peroxiredoxina VI/metabolismo , Catálisis , Dominio Catalítico , Cristalografía por Rayos X , Cisteína/química , Cisteína/metabolismo , Cinética , Modelos Moleculares , Chaperonas Moleculares/química , Oxidación-Reducción , Conformación Proteica , Multimerización de ProteínaRESUMEN
The present study provides data on the insertion of an extra copy of phytochelatin synthase (alr0975) in Anabaena sp. PCC 7120. The recombinant strain (AnFPN-pcs) compared to wild type showed approximately 22.3% increase in growth rate under UV-B, NaCl, heat, CuCl2, carbofuran, and CdCl2. It also registered 2.25-fold enhanced nitrogenase activity and 5-fold higher phytochelatin production. A comparison of the protein profile of wild type with the recombinant strain revealed that recombinant strain accumulated proteins belonging to the following categories: (i) detoxification (nutrient stress induced DNA binding protein, Mn-SOD, Alr0946 (CalA)), (ii) protein folding and modification (molecular chaperone DnaK, FKBP-type peptidyl-prolyl cis-trans isomerase), (iii) nucleotide and amino acid biosynthesis (dihydroorotase and Ketol-acid reductoisomerase), (iv) photosynthesis and respiration (coproporphyrinogen III oxidase, phycocyanin alpha chain, ferredoxin-NADP+ reductase), and (v) transport (sugar transport ATP-binding protein). Thus, it can be concluded that, above category proteins with their respective role in scavenging reactive oxygen species, proper folding of unfolded proteins, and protection of protein from degradation, sustained carbon fixation and energy pool and active transport of sugar together conceivably help the recombinant cyanobacterium (AnFPN-pcs) to cope with abiotic stress employed in the present study. Such recombinant strains have potential for future use as biofertilizer.
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Aminoaciltransferasas/genética , Anabaena/enzimología , Proteínas Bacterianas/genética , Proteoma/genética , Aminoaciltransferasas/metabolismo , Anabaena/crecimiento & desarrollo , Proteínas Bacterianas/metabolismo , Inducción Enzimática , Expresión Génica , Fitoquelatinas/biosíntesis , Proteoma/metabolismo , Estrés FisiológicoRESUMEN
Alkyl hydroperoxide reductase (AhpC) is a key component of a large family of thiol-specific antioxidant (TSA) proteins distributed among prokaryotes and eukaryotes. AhpC is involved in the detoxification of reactive oxygen species (ROS) and reactive sulfur species (RSS). Sequence analysis of AhpC from the cyanobacterium Anabaena sp. PCC 7120 shows that this protein belongs to the 1-Cys class of peroxiredoxins (Prxs). It has recently been reported that enhanced expression of this protein in Escherichia coli offers tolerance to multiple stresses such as heat, salt, copper, cadmium, pesticides and UV-B. However, the structural features and the mechanism behind this process remain unclear. To provide insights into its biochemical function, AhpC was expressed, purified and crystallized by the hanging-drop vapour-diffusion method. Diffraction data were collected to a maximum d-spacing of 2.5 Å using synchrotron radiation. The crystal belonged to space group P2(1)2(1)2(1), with unit-cell parameters a = 80, b = 102, c = 109.6 Å. The structure of AhpC from Anabaena sp. PCC 7120 was determined by molecular-replacement methods using the human Prx enzyme hORF6 (PDB entry 1prx) as the template.
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Anabaena/enzimología , Peroxirredoxinas/química , Cristalización , Cristalografía por Rayos X , Expresión Génica , Peroxirredoxinas/genética , Peroxirredoxinas/aislamiento & purificaciónRESUMEN
Alkyl hydroperoxide reductase (AhpC) is known to detoxify peroxides and reactive sulfur species (RSS). However, the relationship between its expression and combating of abiotic stresses is still not clear. To investigate this relationship, the genes encoding the alkyl hydroperoxide reductase (ahpC) from Anabaena sp. PCC 7120 were introduced into E. coli using pGEX-5X-2 vector and their possible functions against heat, salt, carbofuron, cadmium, copper and UV-B were analyzed. The transformed E. coli cells registered significantly increase in growth than the control cells under temperature (47 degrees C), NaCl (6% w/v), carbofuron (0.025mgml(-1)), CdCl(2) (4mM), CuCl(2) (1mM), and UV-B (10min) exposure. Enhanced expression of ahpC gene as measured by semi-quantitative RT-PCR under aforementioned stresses at different time points demonstrated its role in offering tolerance against multiple abiotic stresses.
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Anabaena/enzimología , Peroxirredoxinas/metabolismo , Estrés Fisiológico , Cloruro de Cadmio/farmacología , Clonación Molecular , Cobre/farmacología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/fisiología , Escherichia coli/efectos de la radiación , Expresión Génica , Peroxirredoxinas/genética , Estrés Fisiológico/genética , Transformación Genética , Rayos UltravioletaRESUMEN
This study offers proteomic elucidation of heat pretreatment-induced alleviation of UV-B toxicity in Anabaena doliolum. Heat-pretreated cells exposed to UV-B showed improved activity of PSI, PSII, whole chain, (14)C fixation, ATP and NADPH contents compared to UV-B alone. Proteomic analysis using two-dimensional gel electrophoresis (2-DE), MALDI-TOF MS/MS and reverse transcription polymerase chain reaction (RT-PCR) of UV-B and heat pretreatment followed by UV-B-treated cells exhibited significant and reproducible alterations in nine proteins homologous to phycocyanin-alpha-chain (PC-alpha-chain), phycoerythrocyanin-alpha-chain (PEC-alpha-chain), hypothetical protein alr0882, phycobilisome core component (PBS-CC), iron superoxide dismutase (Fe-SOD), fructose-1,6-bisphosphate aldolase (FBA), nucleoside diphosphate kinase (NDPK), phosphoribulokinase (PRK) and ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCo) large chain. Except the PEC-alpha-chain, hypothetical protein alr0882 and PBS-CC, all other proteins showed upregulation at low doses of UV-B (U2) and significant downregulation at higher doses of UV-B (U5). The disruption of redox status, signaling, pentose phosphate pathway and Calvin cycle appears to be due to the downregulation of Fe-SOD, NDPK, FBA, PRK and RuBisCo thereby leading to the death of Anabaena. In contrast to this, the upregulation of all the above proteins in heat-pretreated cells, harboring different heat shock proteins (HSPs) like 60, 26 and 16.6, followed by UV-B treatment than only the UV-B-treated ones suggests a protective role of HSPs in mitigating UV-B toxicity.
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Anabaena/efectos de la radiación , Calor , Proteómica , Rayos Ultravioleta , Anabaena/metabolismo , Secuencia de Bases , Cartilla de ADN , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Phytochelatin synthase (PCS) is involved in the synthesis of phytochelatins (PCs), plays role in heavy metal detoxification. The present study describes for first time the functional expression and characterization of pcs gene of Anabaena sp. PCC 7120 in Escherichia coli in terms of offering protection against heat, salt, carbofuron (pesticide), cadmium, copper, and UV-B stress. The involvement of pcs gene in tolerance to above abiotic stresses was investigated by cloning of pcs gene in expression vector pGEX-5X-2 and its transformation in E. coli BL21 (DE3). The E. coli cells transformed with pGEX-5X-pcs showed better growth than control cells (pGEX-5X-2) under temperature (47 degrees C), NaCl (6% w/v), carbofuron (0.025 mg ml(-1)), CdCl2 (4 mM), CuCl2 (1mM), and UV-B (10 min) exposure. The enhanced expression of pcs gene revealed by RT-PCR analysis under above stresses at different time intervals further advocates its role in tolerance against above abiotic stresses.