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1.
Electron. j. biotechnol ; 25: 1-8, ene. 2017. graf, ilus
Article in English | LILACS | ID: biblio-1008175

ABSTRACT

Background: Ascorbic acid (Asc) is one of the most abundant antioxidants and it serves as a major contributor to protect plants against oxidative damage. Plants use two enzymes that participate in the metabolic recycling of Asc. One of these two enzymes is dehydroascorbate reductase (DHAR). It directly regenerates Asc from its oxidized state and thus prevents Asc from being irreversibly hydrolyzed to 2, 3-diketogulonic acid. This study aimed to examine whether over-expression of DHAR leads to an enhanced oxidative stress tolerance in tobacco plants. Results: In this study, we functionally characterized a novel JcDHAR gene from Jatropha curcas and found via quantitative RT-PCR analysis that JcDHAR can be induced with H2O2, salt and PEG stresses. The DHAR activities of transgenic tobacco plants increased from 2.0 to 5.3 fold compared to wild-type plants. As a result, the transgenic plants displayed enhanced tolerance to oxidative stress. Conclusions: Our results indicate that JcDHAR expression can effectively enhance the tolerance to oxidative stress in plants.


Subject(s)
Oxidoreductases/metabolism , Ascorbic Acid/administration & dosage , Tobacco/enzymology , Plants, Genetically Modified/enzymology , Antioxidants/administration & dosage , Oxidoreductases/isolation & purification , Oxidoreductases/genetics , Ascorbic Acid/metabolism , Stress, Physiological , Tobacco/drug effects , Blotting, Western , Plants, Genetically Modified/drug effects , Reactive Oxygen Species , Oxidative Stress , Reverse Transcriptase Polymerase Chain Reaction , Salt Tolerance , Antioxidants/metabolism
2.
Electron. j. biotechnol ; 19(6): 84-90, Nov. 2016. ilus
Article in English | LILACS | ID: biblio-840318

ABSTRACT

Background: 3-Ketosteroid-∆¹-dehydrogenase (KSDD), a flavoprotein enzyme, catalyzes the bioconversion of 4-androstene-3,17-dione (AD) to androst-1,4-diene-3,17-dione (ADD). To date, there has been no report about characterization of KSDD from Mycobacterium neoaurum strains, which were usually employed to produce AD or ADD by fermentation. Results: In this work, Corynebacterium crenatum was chosen asa new host for heterologous expression of KSDD from M. neoaurum JC-12 after codon optimization of the KSDD gene. SDS-PAGE and western blotting results indicated that the recombinant C. crenatum harboring the optimized ksdd (ksdd n) gene showed significantly improved ability to express KSDD. The expression level of KSDD was about 1.6-fold increased C. crenatum after codon optimization. After purification of the protein, we first characterized KSDD from M. neoaurum JC-12, and the results showed that the optimum temperature and pH for KSDD activity were 30°C and pH 7.0, respectively. The Km and Vmax values of purified KSDD were 8.91 µM and 6.43 mM/min. In this work, C. crenatum as a novel whole-cell catalyst was also employed and validated for bioconversion of AD to ADD. The highest transformation rate of AD to ADD by recombinant C. crenatum was about 83.87% after 10 h reaction time, which was more efficient than M. neoaurum JC-12 (only 3.56% at 10 h). Conclusions: In this work, basing on the codon optimization, overexpression, purification and characterization of KSDD, we constructed a novel system, the recombinant C. crenatum SYPA 5-5 expressing KSDD, to accumulate ADDfromADefficiently. This work provided new insights into strengthening sterol catabolism by overexpressing the key enzyme KSDD, for efficient ADD production.


Subject(s)
Androstadienes/metabolism , Corynebacterium/enzymology , Mycobacterium/enzymology , Oxidoreductases/metabolism , Codon , Recombinant Proteins
4.
Arq. bras. endocrinol. metab ; 58(7): 744-749, 10/2014. tab
Article in English | LILACS | ID: lil-726257

ABSTRACT

Objective Our goal was to assess the effects of weight loss on antioxidant enzymes of red blood cells and it’s relation with vitamins A, E and C intake in 30 obese women. Subjects and methods General information, anthropometric measurements, 3-day food recall, and fasting blood samples were collected from 30 obese women at the beginning of the study and after 3 months intervention. Weight loss was set at about 10% of their weight before the intervention. Results Glutathione reductase and catalase activities showed a significant increase (P < 0.01) after weight reduction, but no significant changes were seen in the superoxide dismutase and glutathione peroxidase activities. There was a positive linear correlation between daily vitamin C intake with superoxide dismutase enzyme after intervention (P = 0.004, r = 0.507). There was a negative linear correlation between vitamin E intake and glutathione peroxidase activity before intervention (P = 0.005, r = -0.5). A negative correlation was found between daily vitamin A intake and glutathione reductase enzyme before and after intervention (r = -0.385, r = -0.397, P < 0.05) respectively. No significant correlation was observed between vitamins A, C, E amounts and catalase activity. Conclusions Ten percent weight reduction can have a significant role in increasing antioxidant enzymes activities, especially glutathione reductase, and catalase enzymes in obese women. However, it is important to take into consideration a balanced amount of certain nutrients while administering a diet with limited energy. .


Objetivo Nosso objetivo foi avaliar os efeitos da perda de peso sobre as enzimas antioxidantes de eritrócitos, e a relação destas com a ingestão das vitaminas A, E e C. Sujeitos e métodos Foram coletadas informações gerais e medidas antropométricas, registro alimentar de três dias e amostras de sangue em jejum de 30 mulheres obesas no início do estudo e depois de três meses da intervenção. A perda de peso determinada antes da intervenção foi de 10% do peso. Resultados As atividades da glutationa redutase e da catalase mostraram aumento significativo (P < 0,01) depois da perda de peso, mas não houve mudanças significativas nas atividades da superóxido dismutase e da glutationa peroxidase. Foi observada uma correlação linear positiva entre a ingestão diária de vitamina C e a enzima superóxido dismutase após a intervenção (P = 0,004, r = 0,507). Houve uma correlação linear negativa entre a ingestão de vitamina E e a atividade da glutationa peroxidase antes da intervenção (P = 0,005, r = -0,5). Foi observada uma correlação negativa entre a ingestão diária de vitamina A e a enzima glutationa redutase antes e depois da intervenção (r = -0,385, r = -0,397, P < 0,05), respectivamente. Não foram observadas correlações significativas entre as vitaminas A, C, E e os níveis e a atividade da catalase. Conclusões Uma redução de 10% no peso pode ter um papel significativo no aumento da atividade das enzimas antioxidantes, especialmente na glutationa redutase e catalase em mulheres obesas. Entretanto, é importante levar em consideração uma ingestão equilibrada de certos nutrientes ao se recomendar uma dieta com níveis de energia restritos. .


Subject(s)
Adult , Female , Humans , Middle Aged , Young Adult , Ascorbic Acid/administration & dosage , Obesity/diet therapy , Oxidoreductases/metabolism , Vitamin A/administration & dosage , Vitamin E/administration & dosage , Vitamin E/metabolism , Weight Loss/physiology , Antioxidants/metabolism , Ascorbic Acid/metabolism , Body Weight/physiology , Caloric Restriction , Catalase/blood , Glutathione Peroxidase/blood , Glutathione Reductase/blood , Hemoglobins/analysis , Non-Randomized Controlled Trials as Topic/methods , Oxidoreductases/analysis , Superoxide Dismutase/blood , Vitamin A/metabolism , Weight Loss/drug effects
5.
Salud pública Méx ; 56(4): 402-404, jul.-ago. 2014. tab
Article in Spanish | LILACS | ID: lil-733306

ABSTRACT

La fiebre chikungunya (CHIK) es una enfermedad viral transmitida al ser humano por el mismo vector del dengue, el mosquito Aedes. Además de fiebre y fuertes dolores articulares, produce otros síntomas como mialgias, cefalea, náuseas, cansancio y exantema. No tiene tratamiento específico; el manejo terapéutico de los pacientes se enfoca en el alivio de los síntomas. Históricamente se han reportado brotes de grandes proporciones; incluso desde 2010 se llegó a considerar como una potencial epidemia emergente. En 2013 se introdujo a las islas del Caribe y recientemente se ha reportado en el continente americano. En este trabajo se describe el primer caso confirmado de chikungunya en México, en el municipio de Tlajomulco de Zúñiga, Jalisco, en mayo de 2014, importado de la isla Antigua y Barbuda, en el Caribe, por una mujer de 39 años de edad.


Chikungunya fever (CHIK) is a viral disease transmitted to human beings by the same vector as dengue -the Aedes mosquito. Besides fever and severe pain in the joints, it produces other symptoms such as myalgias, headache, nausea, fatigue and exanthema. There is no specific treatment for it; the therapeutic management of patients focuses on symptom relief. Historically, outbreaks of large proportions have been reported; even since 2010 it was considered to be a potential emerging epidemic. In 2013 it was introduced into the islands of the Caribbean, and it has recently been reported in the American continent. This paper describes the first confirmed case of chikungunya in Mexico -in the municipality of Tlajomulco de Zúñiga, Jalisco, in May, 2014-, which was imported from the Caribbean island of Antigua and Barbuda by a 39 year-old woman.


Subject(s)
Animals , Cattle , Male , Rats , Antidotes/pharmacology , Hot Temperature , Imidazoles/toxicity , Meat , Mitochondria/metabolism , Mutagens/toxicity , Oxygen Consumption/drug effects , Ubiquinone/pharmacology , Antidotes/administration & dosage , Cooking , Diet , Electron Transport Complex II , Electron Transport Complex III/metabolism , Electron Transport Complex IV/metabolism , Electron Transport/drug effects , Food, Fortified , Mitochondria, Heart/drug effects , Mitochondria, Heart/metabolism , Mitochondria, Liver/drug effects , Mitochondria, Liver/metabolism , Mitochondria, Muscle/drug effects , Mitochondria, Muscle/metabolism , Multienzyme Complexes/metabolism , NAD(P)H Dehydrogenase (Quinone)/metabolism , Oxidoreductases/metabolism , Rats, Wistar , Succinate Dehydrogenase/metabolism , Ubiquinone/administration & dosage
6.
Braz. j. microbiol ; 44(4): 1105-1112, Oct.-Dec. 2013. ilus, graf, tab
Article in English | LILACS | ID: lil-705255

ABSTRACT

In the present study enhanced production of glucose aerodehydrogenase from Aspergillus niger has been achieved after optimizing the dose of chemical mutagen ethyl methane sulfonate (EMS) that has not been reported earlier. Different doses of mutagen were applied and a strain was developed basing upon the best production. The selected strain Aspergillus niger EMS-150-F was optimized for nutrient requirements in order to produce enzyme through fermentation and the results showed the best yield at 2% corn steep liquor (CSL), 36 hours fermentation time, pH 5, 30°C temperature, 0.3% KH2PO4, 0.3% urea and 0.06% CaCO3. The enzyme was then purified and resulted in 57.88 fold purification with 52.12% recovery. On kinetic characterization, the enzyme showed optimum activity at pH 6 and temperature 30°C. The Michaelis-Menton constants (Km, Vmax, Kcat and Kcat/Km) were 20 mM, 45.87 U mL-1, 1118.81 s-1 and 55.94 s-1 mM-1, respectively. The enzyme was found to be thermaly stable and the enthalpy and free energy showed an increase with increase in temperature and ΔS* was highly negative proving the enzyme from A. niger EMS-150-F resistant to temperature and showing a very little disorderliness.


Subject(s)
Aspergillus niger/enzymology , Glucose/metabolism , Mutagenesis , Metabolic Engineering/methods , Mutagens/metabolism , Oxidoreductases/metabolism , Aspergillus niger/drug effects , Culture Media/chemistry , Enzyme Stability , Hydrogen-Ion Concentration , Kinetics , Oxidoreductases/chemistry , Oxidoreductases/isolation & purification , Temperature
7.
Braz. j. biol ; 73(3): 617-621, ago. 2013. tab
Article in English | LILACS | ID: lil-689866

ABSTRACT

This study aimed to investigate the effects of ethylene biosynthesis inhibitors on oxidative metabolisms and the in vitro conservation of Lippia filifolia, using the lipid peroxidation index (TBARS), antioxidative enzymes and pigments as biomarkers. We found that EDTA, sodium thiosulfate (STS) and especially Co had protective effects on oxidative stress in tissues cultured in vitro, resulting in a delay of the senescence and the reduction of subcultures frequency, con-tributing to the germplasm conservation of this species.


O objetivo deste estudo foi investigar os efeitos de inibidores da biossíntese do etileno no metabolismo oxidativo e na conservação in vitro de Lippia filifolia. Para isso, foram avaliados o índice de peroxidação lipídica (TBARS), a atividade de enzimas antioxidativas e o conteúdo de pigmentos fotossintéticos e de antocianinas. Os resultados evidenciaram que o EDTA, o tiossulfato de sódio (STS) e, especialmente, o Co apresentaram ação protetora sobre o estresse oxidativo nos tecidos, o que resultou em atraso no início da senescência das culturas e na redução da frequência dos subcultivos, contribuindo para a conservação do germoplasma dessa espécie.


Subject(s)
Ethylenes/antagonists & inhibitors , Lipid Peroxidation/drug effects , Lippia/drug effects , Oxidative Stress/drug effects , Oxidoreductases/metabolism , Biomarkers/analysis , Ethylenes/pharmacology , Lippia/enzymology , Pigments, Biological/analysis , Thiobarbituric Acid Reactive Substances
8.
Braz. j. med. biol. res ; 46(6): 513-520, 02/jul. 2013. graf
Article in English | LILACS | ID: lil-679201

ABSTRACT

Frogs have been used as an alternative model to study pain mechanisms. Since we did not find any reports on the effects of sciatic nerve transection (SNT) on the ultrastructure and pattern of metabolic substances in frog dorsal root ganglion (DRG) cells, in the present study, 18 adult male frogs (Rana catesbeiana) were divided into three experimental groups: naive (frogs not subjected to surgical manipulation), sham (frogs in which all surgical procedures to expose the sciatic nerve were used except transection of the nerve), and SNT (frogs in which the sciatic nerve was exposed and transected). After 3 days, the bilateral DRG of the sciatic nerve was collected and used for transmission electron microscopy. Immunohistochemistry was used to detect reactivity for glucose transporter (Glut) types 1 and 3, tyrosine hydroxylase, serotonin and c-Fos, as well as nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-diaphorase). SNT induced more mitochondria with vacuolation in neurons, satellite glial cells (SGCs) with more cytoplasmic extensions emerging from cell bodies, as well as more ribosomes, rough endoplasmic reticulum, intermediate filaments and mitochondria. c-Fos immunoreactivity was found in neuronal nuclei. More neurons and SGCs surrounded by tyrosine hydroxylase-like immunoreactivity were found. No change occurred in serotonin- and Glut1- and Glut3-like immunoreactivity. NADPH-diaphorase occurred in more neurons and SGCs. No sign of SGC proliferation was observed. Since the changes of frog DRG in response to nerve injury are similar to those of mammals, frogs should be a valid experimental model for the study of the effects of SNT, a condition that still has many unanswered questions.


Subject(s)
Animals , Male , Ganglia, Spinal/metabolism , Ganglia, Spinal/ultrastructure , Oxidoreductases/metabolism , Proto-Oncogene Proteins c-fos/metabolism , Sciatic Nerve/injuries , Serotonin/metabolism , Cellular Microenvironment , Glucose Transport Proteins, Facilitative/metabolism , Immunohistochemistry , Microscopy, Electron, Transmission , NADPH Dehydrogenase/metabolism , Neuralgia/metabolism , Rana catesbeiana , /metabolism
9.
Biol. Res ; 46(2): 121-130, 2013. ilus
Article in English | LILACS | ID: lil-683988

ABSTRACT

Orthodox seeds become desiccation-sensitive as they undergo germination. As a result, germinating seeds serve as a model to study desiccation sensitivity in plant tissues. The effects of the rate of drying on the viability, respiratory metabolism and free radical processes were thus studied during dehydration and wet storage of radicles of Pisum sativum. For both drying regimes desiccation could be described by exponential and inverse modified functions. Viability, as assessed by germination capacity and tetrazolium staining, remained at 100% during rapid (< 24 h) desiccation. However, it declined sharply at c. 0.26 g g¹ dm following slow (c. 5 days) drying. Increasing the rate of dehydration thus lowered the critical water content for survival. Rapid desiccation was also associated with higher activities and levels of malate dehydrogenase and the oxidized form of nicotinamide adenine dinucleotide. It was also accompanied by lower hydroperoxide levels and membrane damage. In addition, the activitiy of glutathione reductase was greater during rapid drying. Ageing may have contributed to increased damage during slow dehydration, since viability declined even in wet storage after two weeks. The results presented are consistent with rapid desiccation reducing the accumulation of damage resulting from desiccation-induced aqueous-based deleterious reactions. In addition, they show that radicles are a useful model to study desiccation sensitivity in plant tissues.


Subject(s)
Desiccation/methods , Lipid Peroxidation/physiology , Peas/physiology , Plant Roots/metabolism , Seeds/physiology , Water/metabolism , Antioxidants/metabolism , Germination/physiology , NAD , Oxidative Stress , Oxidoreductases/metabolism , Peas/metabolism , Phosphofructokinases/metabolism , Tissue Survival/physiology
10.
Indian J Biochem Biophys ; 2012 Jun; 49(3): 195-201
Article in English | IMSEAR | ID: sea-140236

ABSTRACT

The impact of five Bacillus thuringiensis (Bt) cotton varieties and their respective isogenic non-Bt(NBt) isolines (ANKUR-2534, MECH-6304, RCH-317, ANKUR-651 and MECH-6301) was assessed on the key soil enzymes i.e., dehydrogenase, alkaline phosphatase and urease in their rhizosphere at four growth stages of the crop, namely vegetative, flowering, bolling and harvesting. These varieties were grown on farmer’s field in villages 22 miles and 24 miles of Ganganagar District of Rajasthan State in India. Results showed that dehydrogenase, alkaline phosphatase and urease activities were higher in rhizosphere of Bt isolines as compared to NBt isolines of all the varieties. Except phosphatase, differences in dehydrogenase and urease activities in rhizosphere of Bt and NBt isolines of all five varieties were significant (P<0.05). Maximum enhancement in the three enzymes activities was observed in MECH-6304 Bt isoline rhizosphere. Maximum and minimum activities of dehydrogenase and urease were observed in MECH-6304 and RCH-317 Bt isolines, respectively, whereas phosphatase activity was maximum and minimum in MECH-6304 and ANKUR-651 Bt isolines, respectively. Maximum dehydrogenase and urease activities were observed at boll formation and minimum at flowering and harvesting stage, respectively, while maximum phosphatase activity was observed at vegetative stage and minimum at harvesting stage. In conclusion, all the studied Bt isolines of cotton varieties showed no adverse effect on dehydrogenase, alkaline phosphatase and urease activities in the rhizosphere.


Subject(s)
Alkaline Phosphatase/chemistry , Alkaline Phosphatase/metabolism , Bacillus thuringiensis/enzymology , Bacillus thuringiensis/genetics , Gossypium/enzymology , Gossypium/genetics , Gossypium/growth & development , Oxidoreductases/chemistry , Oxidoreductases/metabolism , Plants, Genetically Modified , Rhizosphere , Soil/analysis , Urease/chemistry , Urease/metabolism
11.
Article in English | WPRIM | ID: wpr-14960

ABSTRACT

Six transmembrane protein of prostate 2 (STAMP2) plays a key role in linking inflammatory and diet-derived signals to systemic metabolism. STAMP2 is induced by nutrients/feeding as well as by cytokines such as TNFalpha, IL-1beta, and IL-6. Here, we demonstrated that STAMP2 protein physically interacts with and decreases the stability of hepatitis B virus X protein (HBx), thereby counteracting HBx-induced hepatic lipid accumulation and insulin resistance. STAMP2 suppressed the HBx-mediated transcription of lipogenic and adipogenic genes. Furthermore, STAMP2 prevented HBx-induced degradation of IRS1 protein, which mediates hepatic insulin signaling, as well as restored insulin-mediated inhibition of gluconeogenic enzyme expression, which are gluconeogenic genes. We also demonstrated reciprocal expression of HBx and STAMP2 in HBx transgenic mice. These results suggest that hepatic STAMP2 antagonizes HBx-mediated hepatocyte dysfunction, thereby protecting hepatocytes from HBV gene expression.


Subject(s)
Animals , Female , Gene Expression , Gluconeogenesis/genetics , Hep G2 Cells , Humans , Insulin/pharmacology , Insulin Receptor Substrate Proteins/genetics , Insulin Resistance , Lipid Metabolism , Liver/metabolism , Male , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Inbred CBA , Mice, Transgenic , Oxidoreductases/metabolism , Phosphorylation , Protein Binding , Protein Processing, Post-Translational , Proteolysis , Receptor, Insulin/metabolism , Trans-Activators/physiology , Transcriptional Activation
12.
Electron. j. biotechnol ; 14(4): 4-4, July 2011. ilus, tab
Article in English | LILACS | ID: lil-640499

ABSTRACT

A strain KSUCr3 with extremely high Cr(VI)-reducing ability under alkaline conditions was isolated from hypersaline soda lakes and identified as Amphibacillus sp. on the basis of 16S rRNA gene sequence analysis. The results showed that Amphibacillus sp. strain KSUCr3 was tolerance to very high Cr(VI) concentration (75 mM) in addition to high tolerance to other heavy metals including Ni2+ (100 mM), Mo2+ (75 mM), Co2+ (5 mM), Mn2+ (100 mM), Zn2+ (2 mM), Cu2+ (2 mM) and Pb (75 mM). Strain KSUCr3 was shown to be of a high efficiency in detoxifying chromate, as it could rapidly reduce 5 mM of Cr(VI) to a non detectable level over 24 hrs. In addition, strain KSUCr3 could reduce Cr(VI) efficiently over a wide range of initial Cr(VI) concentrations (1-10 mM) in alkaline medium under aerobic conditions without significant effect on the bacterial growth. Addition of glucose, NaCl and Na2CO3 to the culture medium caused a dramatic increase in Cr(VI)-reduction by Amphibacillus sp. strain KSUCr3. The maximum chromate removal was exhibited in alkaline medium containing 1.5 percent Na2CO3, 0.8 percent glucose, and 1.2 percent NaCl, at incubation temperature of 40ºC and shaking of 100 rpm. Under optimum Cr(VI) reduction conditions, Cr(VI) reduction rate reached 237 uMh¹ which is one of the highest Cr(VI) reduction rate, under alkaline conditions and high salt concentration, compared to other microorganisms that has been reported so far. Furthermore, the presence of other metals, such as Ni2+, Co2+, Cu2+ and Mn2+ slightly stimulated Cr(VI)-reduction ability by the strain KSUCr3.The isolate, Amphibacillus sp. strain KSUCr3, exhibited an ability to repeatedly reduce hexavalent chromium without any amendment of nutrients, suggesting its potential application in continuous bioremediation of Cr(VI). The results also revealed the possible isolation of potent heavy metals resistant bacteria from extreme environment such as hypersaline soda lakes.


Subject(s)
Bacillaceae , Biodegradation, Environmental , Chromium/metabolism , Oxidoreductases/metabolism , Lakes , Metals, Heavy , Oxidoreductases/isolation & purification
13.
Article in English | WPRIM | ID: wpr-175680

ABSTRACT

A 42-yr-old man with hepatitis B virus associated liver cirrhosis was admitted to the emergency room because of multiple seizures, a history of chills and myalgia over the previous 2 weeks, and 3 days of melena. He was febrile with a temperature of 38.0degrees C. There were no symptoms and signs related to the genitourinary system, skin, or joints. Three sets of blood cultures were obtained and oxidase-positive, gram-negative diplococci were detected after 25.9-26.9 hr of incubation in all aerobic vials. The organism was positive for catalase and oxidase, and was identified as Neisseria gonorrhoeae, using a Vitek Neisseria-Haemophilus Identification card (bioMerieux Vitek, Inc., USA). Further, 16S rRNA sequencing of this isolate revealed a 99.9% homology with the published sequence of N. gonorrhoeae strain NCTC 83785 (GenBank Accession No. NR_026079.1). Acute bleeding by variceal rupture seems to be a likely route of introduction of N. gonorrhoeae from the mucosa into the blood. To the best of our knowledge, this is the first case of gonococcal bacteremia in Korea.


Subject(s)
Adult , Bacteremia/complications , Catalase/metabolism , Esophageal and Gastric Varices/complications , Gastrointestinal Hemorrhage/etiology , Gonorrhea/complications , Humans , Ligation , Liver Cirrhosis/diagnosis , Male , Neisseria gonorrhoeae/genetics , Oxidoreductases/metabolism , RNA, Ribosomal, 16S/chemistry , Sequence Analysis, DNA
14.
Indian J Biochem Biophys ; 2010 Oct; 47(5): 306-310
Article in English | IMSEAR | ID: sea-135281

ABSTRACT

Chill treatment of potato tubers for 8 days induced mitochondrial O2 consumption by cyanide-insensitive alternative oxidase (AOX). About half of the total O2 consumption in such mitochondria was found to be sensitive to salicylhydroxamate (SHAM), a known inhibitor of AOX activity. Addition of catalase to the reaction mixture of AOX during the reaction decreased the rate of SHAM-sensitive O2 consumption by nearly half, and addition at the end of the reaction released half of the O2 consumed by AOX, both typical of catalase action on H2O2. This reaffirmed that the product of reduction of O2 by plant AOX was H2O2 as found earlier and not H2O as reported in some recent reviews.


Subject(s)
Hydrogen Peroxide/metabolism , Mitochondria/metabolism , Oxidoreductases/metabolism , Plant Proteins/metabolism , Solanum tuberosum/metabolism , Solanum tuberosum/ultrastructure
15.
Rev. biol. trop ; 57(1/2): 223-234, March-June 2009. graf, mapas, tab
Article in English | LILACS | ID: lil-637714

ABSTRACT

Soil dehydrogenase activity is a good indicator of overall microbial activity in soil, and it can serve as a good indicator of soil condition. However, seasonal changes in soil moisture content may have an effect on soil dehydrogenase activity, making an accurate assessment of soil condition difficult. In this study, we attempted to determine the significance of soil dehydrogenase activity for assessing soil condition, and we attempted to find a way to account for the influence of soil moisture content on soil dehydrogenase activity. Soils were sampled in dry evergreen forest (original vegetation), bare ground (severely degraded) and Acacia plantation plots established on bare ground in 1986 and 1987 in Sakaerat, Thailand. Soil physico-chemical characteristics and dehydrogenase activity in the Acacia plantation soil had few differences from those in the evergreen forest soil. Soil dehydrogenase activity varied significantly between the bare ground and the forests regardless of the season (wet or dry), while the season did not produce a significant variation in soil dehydrogenase activity, as determined by repeated measures analysis of variance (p=0.077). The physico-chemical data provided the first principal component as a good measure of soil fertility. Values of soil dehydrogenase activity significantly correlated to scores of the soil samples of the first principal component (R=0.787, p<0.001). We found that soil dehydrogenase activity is a useful indicator of the extent of soil degradation and the rehabilitative effects of reforestation in this part of Thailand. Rev. Biol. Trop. 57 (1-2): 223-234. Epub 2009 June 30.


Subject(s)
Acacia/metabolism , Oxidoreductases/metabolism , Soil Microbiology , Soil/analysis , Trees/metabolism , Seasons , Thailand
16.
Mem. Inst. Oswaldo Cruz ; 104(1): 18-26, Feb. 2009. graf, tab, mapas
Article in English | LILACS | ID: lil-507201

ABSTRACT

In order to establish the insecticide susceptibility status for Anopheles darlingi in Colombia, and as part of the National Network on Insecticide Resistance Surveillance, five populations of insects from three Colombian states were evaluated. Standardised WHO and CDC bottle bioassays, in addition to microplate biochemical assays, were conducted. Populations with mortality rates below 80 percent in the bioassays were considered resistant. All field populations were susceptible to deltamethrin, permethrin, malathion and fenitrothion. Resistance to lambda-cyhalothrin and DDT was detected in the Amé-Beté population using both bioassay methods with mortality rates of 65-75 percent. Enzyme levels related to insecticide resistance, including mixed function oxidases (MFO), non-specific esterases (NSE), glutathione S-transferases and modified acetylcholinesterase were evaluated in all populations and compared with a susceptible natural strain. Only mosquitoes from Amé-Beté presented significantly increased levels of both MFO and NSE, consistent with the low mortalities found in this population. The continued use of lambda-cyhalothrin for An. darlingi control in this locality has resulted in a natural resistance to this insecticide. In addition, DDT resistance is still present in this population, although this insecticide has not been used in Colombia since 1992. Increased metabolism through MFO and NSE may be involved in cross-resistance between lambda-cyhalothrin and DDT, although kdr-type nerve insensitivity cannot be discarded as a possible hypothesis. Additional research, including development of a kdr specific assay for An. darlingi should be conducted in future studies. Our data demonstrates the urgent need to develop local insecticide resistance management and surveillance programs throughout Colombia.


Subject(s)
Animals , Female , Anopheles/enzymology , Esterases/metabolism , Insect Vectors/enzymology , Insecticides/pharmacology , Oxidoreductases/metabolism , Anopheles/drug effects , Biological Assay , Colombia , DDT , Insecticide Resistance , Insect Vectors/drug effects , Nitriles/pharmacology , Pyrethrins/pharmacology
17.
Biol. Res ; 42(3): 315-326, 2009. ilus, tab
Article in English | LILACS | ID: lil-531965

ABSTRACT

The ascorbate-glutathione (ASC-GSH) cycle has an important role in defensive processes against oxidative damage generated by drought stress. In this study, the changes that take place in apoplastic and symplastic ASC-GSH cycle enzymes of the leaf and petiole were investigated under drought stress causing leaf rolling in Ctenanthe setosa (Rose.) Eichler (Marantaceae). Apoplastic and symplastic extractions of leaf and petiole were performed at different visual leaf rolling scores from 1 to 4 (1 is unrolled, 4 is tightly rolled and the others are intermediate forms). Glutathione reductase (GR), a key enzyme in the GSH regeneration cycle, and ascorbate (ASC) were present in apoplastic spaces of the leaf and petiole, whereas dehydroascorbate reductase (DHAR), which uses glutathione as reductant, monodehydroascorbate reductase (MDHAR), which uses NAD(P)H as reductant, and glutathione were absent. GR, DHAR and MDHAR activities increased in the symplastic and apoplastic areas of the leaf. Apoplastic and symplastic ASC and dehydroascorbate (DHA), the oxidized form of ascorbate, rose at all scores except score 4 of symplastic ASC in the leaf. On the other hand, while reduced glutathione (GSH) content was enhanced, oxidized glutathione (GSSG) content decreased in the leaf during rolling. As for the petiole, GR activity increased in the apoplastic area but decreased in the symplastic area. DHAR and MDHAR activities increased throughout all scores, but decreased to the score 1 level at score 4. The ASC content of the apoplast increased during leaf rolling. Conversely, symplastic ASC content increased at score 2, however decreased at the later scores. While the apoplastic DHA content declined, symplastic DHA rose at score 2, but later was down to the level of score 1. While GSH content enhanced during leaf rolling, GSSG content did not change except at score 2. As well, there were good correlations between leaf rolling and ASC-GSH cycle enzyme activities ...


Subject(s)
Ascorbic Acid/metabolism , Glutathione/metabolism , Marantaceae/enzymology , Plant Leaves/enzymology , Rosa/enzymology , Droughts , Glutathione Reductase/metabolism , NADH, NADPH Oxidoreductases/metabolism , Oxidoreductases/metabolism , Stress, Physiological
18.
Article in English | WPRIM | ID: wpr-164459

ABSTRACT

Present study was undertaken to study the effect of cypermethrin on oxidative stress after chronic dermal application. The insecticide was applied dermally at 50 mg/kg body weight in different groups of Wistar rats of either sex weighing 150~200 g. Significant (p < 0.05) increase in catalase activity was observed after 30 days of exposure. However, the superoxide dismutase activity declined significantly after 60 days of exposure. The activity of glutathione peroxidase and blood glutathione levels declined significantly (p < 0.05) after 30 days of cypermethrin dermal application. However, the activity of glutathione S-transferase increased significantly (p < 0.05) in all groups after 60 days of dermal exposure. Significant increase in lipid peroxidation was observed from 30 days onwards and reached a peak after 120 days of application.


Subject(s)
Administration, Cutaneous , Animals , Female , Glutathione/blood , Insecticides/toxicity , Lipid Peroxidation/drug effects , Male , Oxidative Stress/drug effects , Oxidoreductases/metabolism , Pyrethrins/toxicity , Rats , Rats, Wistar
19.
Rev. argent. microbiol ; 40(2): 120-123, abr.-jun. 2008. tab
Article in English | LILACS | ID: lil-634590

ABSTRACT

The incorporation of biosolids to soil is a strategy aiming at the re-location of these materials in the environment with a useful end: soil fertilization. In this work, the response of two Argiudoll soils (one with more than 100 years of agriculture and the other, a virgin one) to biosolid incorporation was studied under laboratory conditions. To measure this response, soil enzymatic biodescriptors, such as dehydrogenase and urease activities, and tests related to plant physiology (the root elongation test) were employed. The addition of the biosolid to both soils had a stimulating effect though different on each soil according to the added dose. Adjustment of the regression line for dehydrogenase activity with root elongation was positive and statistically significant (p<0.001). Results suggest that biodescriptors employed were suitable for studying the impact of amended biosolids on different soils.


La incorporación de biosólidos al suelo es una estrategia que tiene como objetivo la reubicación de estos materiales en el ambiente con un fin útil, como es la fertilización del suelo. En este trabajo se estudió, en condiciones controladas de laboratorio, la respuesta de dos suelos Argiudoles (uno con más de 100 años de agricultura y otro virgen) frente a la perturbación físico-química y biótica que genera la incorporación de un biosólido. Para medir esta respuesta se emplearon dos biodescriptores edáficos (las actividades deshidrogenasa y ureasa) y un tercero referido a la fisiología vegetal, la prueba de elongación de raíces. La incorporación del biosólido en ambos suelos, en general no deprimió el funcionamiento de las actividades enzimáticas estudiadas; contrariamente, según la dosis aportada tuvo un efecto estimulante, aunque diferente, entre ambos suelos. El ajuste de la recta de regresión de la actividad deshidrogenasa con la elongación de las plántulas fue positivo y altamente significativo, lo que indica la complementaridad de ambos descriptores. Los resultados obtenidos sugieren que los biodescriptores empleados resultaron aptos para estudiar el impacto que produce la incorporación de biosólidos a suelos agrícolas.


Subject(s)
Oxidoreductases/metabolism , Plant Roots/enzymology , Plant Roots/growth & development , Sewage , Soil , Urease/metabolism , Argentina
20.
Saudi Medical Journal. 2008; 29 (1): 23-29
in English | IMEMR | ID: emr-90038

ABSTRACT

To elucidate the expression of epoxygenases belonging to cytochrome P-450 mono-oxygenases [CYP2] family in rat ischemic myocardium at varying reperfusion periods, and the effect of epoxygenase inhibition on the post-ischemic heart. The current study was conducted in the Department of Pharmacology, Medical College of Wuhan University, China, between September 2004 and June 2005. Rats were subjected to 40 minutes of myocardial ischemia, followed by 0, 15, 60, and 180 minutes of reperfusion. Superoxide generation was assayed by confocal microscopy, CYP2B1/2, 2C6, 2E1, 2J3 gene expressions were determined by reverse transcriptase polymerase chain reaction. Fourteen, 15-dihydroxyeicosatrienoic acid [DHET] concentration was measured by enzyme-linked immunosorbent assay. The effects of the CYP epoxygenase inhibitor N-methylsulphonyl-6-[2-propargyloxyphenyl] hexanamide [MS-PPOH] on myocardial damage and superoxide generation caused by 60 minutes of reperfusion were also evaluated. During myocardial ischemia/reperfusion, CYP2C6 and 2J3 mRNA expression were up-regulated with the peak level at 15 minutes of reperfusion; CYP2E1 gene expression decreased in a time dependent manner and reached the minimum level at 180 minutes of post-ischemia. Meanwhile, no obvious variations of CYP2B1/2 gene expression were detected during different reperfusion periods. Fourteen, 15-DHET significantly increased during reperfusion in ischemic hearts. The MS-PPOH pretreatment [15 mg/kg] effectively reduced myocardial damage and superoxide production. There are changes in gene expression of individual isozymes and an elevation of CYP epoxygenase activity involved in myocardial reperfusion injury in vivo. Epoxygenase inhibition plays a protective role in cardiac post-ischemic damage


Subject(s)
Male , Animals , Myocardial Reperfusion Injury/enzymology , Oxidoreductases/metabolism , Cytochrome P-450 Enzyme System , Enzyme-Linked Immunosorbent Assay , Rats, Sprague-Dawley , Gene Expression
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