Different Concentrations Of Cysteine Research Articles

Effects of supplementation of cryopreservation media with cysteine on the post-thaw quality and fertility of brown-marbled grouper (Epinephelus fuscoguttatus) spermatozoa

The cryopreservation process is associated with the generation of excessive reactive oxygen species, which causes a series of cellular damage to spermatozoa. The objective of the current study was to investigate the effect of different concentrations of cysteine on post-thaw sperm quality of brown-marbled grouper sperm. Semen samples were frozen with cysteine supplemented at 0.5, 1, 2, 5, 10 mM and the control group (no additive). After thawing, sperm quality parameters were analyzed. In comparison to the control, cysteine treatment groups yielded relatively higher sperm total motility, progressive motility, and curvilinear velocity. Different concentrations of cysteine had no effect on average path velocity, straight linear velocity and viability (P > 0.05), while an increase in the concentration of cysteine resulted in a significant improvement in the mitochondrial membrane potential, SOD activity, and ATP content (P < 0.05). As for lipid peroxidation, the extent of which in cysteine treated spermatozoa was less than the control, although the differences were not statistically significant (P > 0.05). In terms of fertilizing capacity, a greater hatching rate (91.7 ± 1.2%) was obtained in thawed sperm treated with 2 mM cysteine, compared to the control (84.3 ± 4.2%; P < 0.05). Overall, it is concluded that the addition of cysteine is helpful in maintaining the function of frozen-thawed brown-marbled grouper sperm, which can be recommended as an effective antioxidant to improve the semen cryopreservation efficiency.

Effect of Cysteine in Stimulating Some Active Compounds in Garlic Callus Under Different Light Spectra in Vitro

This study was conducted in tissue culture laboratories, Faculty of agriculture, University of Kufa in 2020. The experiment included studying the effect of two factors: type of light: (mixture spectra of red and blue LED R16 : B2), (Fluorescent : normal white light) in interaction with different concentrations of cysteine( 0, 50, and 100 mg.L-1). A completely randomized design (C.R.D) were used with two factor and three replicates. The combined spectra (LED R16:B2) increased the active compounds Di-allyldisulfide and Vinyldithiin (131.33,121.41μg.g-1 F.W. ) respectively. Cysteine (100 mg.L-1) was significantly superior compare to other treatments in producing Di-allyldisulfide and Vinyldithiin content (158.87, 144.35 μg.g-1 F.W) respectively. Results also indicated that the interaction treatment between (LED R16:B2) and (Cysteine 100 mg.L-1) gave significant increase in Di-allyldisulfide and Vinyldithiin content (184.28, 146.07μg.g-1 F.W) respectively. While the tretment (Fluorescent W) and (Cysteine 50 mg.L-1) gave significant increase in Allicin content (195.38 μg.g-1 F.W).

The role of low concentrations of some sulfuric antioxidants on the semen characteristics of rams

This study aims to investigate the effect of low concentrations of sulfuric antioxidants on sperm of rams. This study was conducted in the field of sheep and goats of the Department of Livestock in the collage of Agricultural Engineering Sciences, University of Baghdad. The semen was collected using the artificial vagina at weekly rate (Pooled semen) and was subjected to different tests and then was divided into seven treatments but different concentrations of cysteine (0.5, 1mM) and glutathione (0.5, 1mM) and taurine (0.5, 1mM).The sample of the semen was diluted with Tris dilution (10: 1). The results showed that the low concentrations of glutathione, cysteine and taurine resulted in an improvement in the motility and integrity of the plasma membrane, dead sperm, DNA damage and survival sperm during the conservation period (0, 24, 48 hours).

Molecular and biochemical characterization of key enzymes in the cysteine and serine metabolic pathways of Acanthamoeba castellanii

BackgroundAcanthamoeba spp. can cause serious human infections, including Acanthamoeba keratitis, granulomatous amoebic encephalitis and cutaneous acanthamoebiasis. Cysteine biosynthesis and the L-serine metabolic pathway play important roles in the energy metabolism of Acanthamoeba spp. However, no study has confirmed the functions of cysteine synthase (AcCS) in the cysteine pathway and phosphoglycerate dehydrogenase (AcGDH) or phosphoserine aminotransferase (AcSPAT) in the non-phosphorylation serine metabolic pathway of Acanthamoeba.MethodsThe AcCS, AcGDH and AcSPAT genes were amplified by PCR, and their recombinant proteins were expressed in Escherichia coli. Polyclonal antibodies against the recombinant proteins were prepared in mice and used to determine the subcellular localisation of each native protein by confocal laser scanning microscopy. The enzymatic activity of each recombinant protein was also analysed. Furthermore, each gene expression level was analysed by quantitative PCR after treatment with different concentrations of cysteine or L-serine.ResultsThe AcCS gene encodes a 382-amino acid protein with a predicted molecular mass of 43.1 kDa and an isoelectric point (pI) of 8.11. The AcGDH gene encodes a 350-amino acid protein with a predicted molecular mass of 39.1 kDa and a pI of 5.51. The AcSPAT gene encodes a 354-amino acid protein with a predicted molecular mass of 38.3 kDa and a pI of 6.26. Recombinant AcCS exhibited a high cysteine synthesis activity using O-acetylserine and Na2S as substrates. Both GDH and SPAT catalysed degradation, rather than synthesis, of serine. Exogenous L-serine or cysteine inhibited the expression of all three enzymes in a time- and dose-dependent manner.ConclusionsThis study demonstrated that AcCS participates in cysteine biosynthesis and serine degradation via the non-phosphorylation serine metabolic pathway, providing a molecular basis for the discovery of novel anti-Acanthamoeba drugs.

Cysteine protects rabbit spermatozoa against reactive oxygen species-induced damages.

The process of cryopreservation results in over-production of reactive oxygen species, which is extremely detrimental to spermatozoa. The aim of this study was to investigate whether addition of cysteine to freezing extender would facilitate the cryosurvival of rabbit spermatozoa, and if so, how cysteine protects spermatozoa from cryodamages. Freshly ejaculated semen was diluted with Tris-citrate-glucose extender supplemented with different concentrations of cysteine. The motility, intact acrosomes, membrane integrity, mitochondrial potentials, 8-hydroxyguanosine level and sperm-zona pellucida binding capacity were examined. Furthermore, glutathione peroxidase (GPx) activity, glutathione content (GSH), and level of reactive oxygen species (ROS) and hydrogen peroxide of spermatozoa were analyzed. The values of motility, intact acrosomes, membrane integrity, mitochondrial potentials and sperm-zona pellucida binding capacity of the frozen-thawed spermatozoa in the treatment of cysteine were significantly higher than those of the control. Addition of cysteine to extenders improved the GPx activity and GSH content of spermatozoa, while lowered the ROS, DNA oxidative alterations and lipid peroxidation level, which makes spermatozoa avoid ROS to attack DNA, the plasma membrane and mitochondria. In conclusion, cysteine protects spermatozoa against ROS-induced damages during cryopreservation and post-thaw incubation. Addition of cysteine is recommended to facilitate the improvement of semen preservation for the rabbit breeding industry.

Electrochemical and Stress Corrosion Cracking Behavior of Alpha-Al Bronze in Sulfide-Polluted Salt Water: Effect of Environmentally-Friendly Additives

The stress corrosion cracking (SCC) behavior of α-Al bronze alloy (Cu7Al) was investigated in 3.5% NaCl solution in the absence and in the presence of different concentrations of Na2S under open circuit potentials using the constant slow strain rate technique. Also, the addition of different concentrations of cysteine (cys), and alanine (ala) to the test solution, as corrosion inhibitors, was studied. Increasing the sulfide ions concentration in polluted salt water resulted in a reduction in the maximum stress (σmax) and an increase in the susceptibility of α-Al bronze towards SCC. The addition of ala and cys to the test electrolyte increased the time to failure by changing the mode of failure from brittle transgranular cracking to ductile failure. Electrochemical tests were performed to assist the interpretation of the SCC data. Electrochemical impedance spectroscopy (EIS) was used to investigate the mechanism of corrosion inhibition. The results support film rupture and anodic dissolution at slip steps as the operating mechanism of the SCC process. Therefore, cys and ala can be considered as potential environmentally-friendly corrosion inhibitors for the SCC of α-Al bronze in 3.5% NaCl solution containing sulfide ions.

275 EFFECT OF REACTIVE OXYGEN SPECIES DURING IN VITRO MATURATION ON PORCINE OOCYTE NUCLEAR MATURATION AND DEVELOPMENTAL COMPETENCE

The generation of excessive reactive oxygen species (ROS) may contribute to the decreased competence of in vitro matured (IVM) oocytes. However, ROS are also generated in normal cellular metabolism and can be important regulators of cellular functions. The objective of this study was to examine the effect of ROS during IVM on porcine oocyte nuclear maturation and subsequent embryonic development. Oocytes were matured in different redox environments for 40 h in 7% CO2 in air at 38.7°C. The basic maturation medium was defined PPM supplemented with 1 mM hypoxanthine. Reactive oxygen species were generated by the hypoxanthine–xanthine oxidase (XOD) system at 3 different concentrations: XOD0 (0 mU), XOD1 (1 mU), and XOD10 (10 mU). In each XOD treatment, 2 different concentrations of cysteine (Cys) were added as an antioxidant: Cys1 (0.57 mM) and Cys2 (1.14 mM). This resulted in 6 experimental treatments in a 3 × 2 factorial design; XOD0-Cys1 was considered the control. For fertilization, gametes were co-incubated in modified Tween medium B with milk powder for 5 h and then cultured in NCSU-23 medium in 5% CO2, 10% O2 for 6 days, at which point cleavage, blastocyst development, and blastocyst cell number were determined (30–50 per treatment per replicate; 4 replicates). Data were analysed by two-way ANOVA, and differences were determined by Fisher’s least significant difference multiple-comparison test; percentage data were arcsin transformed (significance, P &lt; 0.05). Results are shown in Table 1. Percentage of mature oocytes was not different between any XOD0 and XOD1 treatments, but maturation was decreased in both XOD10 treatments. Embryonic cleavage was also decreased in both XOD10 treatments compared with the control. Blastocyst development was decreased in XOD0-Cys2 and XOD10-Cys1 when compared with the control. Blastocyst total cell number was not different between any treatments (P &gt; 0.05). In conclusion, 10-mU XOD during IVM resulted in decreased nuclear maturation, embryonic cleavage, and blastocyst development, possibly due to excessive ROS generated by XOD. The negative effect of high levels of XOD on blastocyst formation could be reversed by adding additional antioxidant capacity to the environment (Cys2). This result suggests that adequate ROS balance is important for oocyte quality. Interestingly, adding extra antioxidant capacity alone (XOD0-Cys2) was detrimental to blastocyst formation, possibly due to the creation of an environment that was too reduced. These results demonstrate the importance of keeping the redox environment balanced during oocyte maturation. Excessive oxidative or reducing environments both appear to be detrimental to oocyte developmental competence. Table 1.Nuclear maturation and developmental competence of oocytes matured in different redox environments

Cysteine enhances activity and stability of immobilized papain

Immobilization of papain on Sepharose 6B in the presence of different concentrations of cysteine affected the enzyme activity depending on cysteine concentration. The maximum specific activity was observed when papain was immobilized with 200 mM cysteine. The immobilization process brought significant enhancement of stability to temperature and extreme pH values with respect to free papain. After immobilization, the optimum temperature of papain activity increased by 20 degrees C (from 60 to 80 degrees C) and its optimum pH activity shifted from 6.5 to 8.0. Catalytic efficiency (k(cat)/K(m)) and specific activity of the immobilized enzyme do not significantly change after immobilization. The temperature profile of this form of immobilized papain showed a broad range of activity compared with both free and immobilized form of papain in the absence of cysteine. This significant behavior in terms of activation energy is also discussed.

Effects of Cysteine During In Vitro Maturation of Porcine Oocytes Under Low Oxygen Tension on Their Subsequent In Vitro Fertilization and Development

In this study, we evaluated the effect of different concentrations of cysteine in in vitro maturation (IVM) medium during IVM under low oxygen tension (5% O(2)) of porcine oocytes on the intracellular content of glutathione (GSH) and subsequent in vitro fertilization (IVF) and development. Cumulus oocyte complexes (COCs) were collected from ovaries obtained at a local slaughterhouse, cultured in IVM medium supplemented with 0 (control), 0.05, 0.1, 0.2 or 0.6 mM cysteine for 44-46 h, fertilized in vitro and subsequently cultured for 6 days in total. The GSH content of the IVM oocytes exposed to 0, 0.05, 0.1, 0.2 or 0.6 mM cysteine increased significantly (P<0.05) as the concentration of cysteine increased (12.2, 14.0, 15.1, 16.4 and 16.4 pmol/oocyte, respectively). However, the rates of oocyte maturation, sperm penetration, male pronuclear formation, monospermy and even cleavage on Day 2 (the day of IVF was defined as Day 0) and blastocyst formation on Day 6 did not differ among the groups. Moreover, the cell numbers of blastomeres in blastocysts were uniform among the groups. These results indicate that supplementation with 0.05-0.6 mM cysteine during IVM under 5% O(2) tension significantly increased the intracellular GSH contents of IVM oocytes; however, it had no promoting effects on nuclear maturation, fertilization, male pronucleus formation and subsequent embryonic development to the blastocyst stage.

Glutathione content and embryo development after in vitro fertilisation of pig oocytes matured in the presence of a thiol compound and various concentrations of cysteine.

The present study examined the effect of different concentrations of cysteine in the presence of a thiol compound, beta-mercaptoethanol (BME), during in vitro maturation (IVM) of pig oocytes on cumulus expansion, nuclear maturation, intracellular glutathione (GSH) level and subsequent embryonic development after in vitro fertilisation (IVF). In experiment 1, oocytes were matured in NCSU 23 medium containing 10% porcine follicular fluid, 25 microM BME, 0.5 microgram/ml LH, 0.5 microgram/ml FSH and 0, 0.1, 0.2 or 0.4 mg/ml cysteine for 20-22 h and then without hormonal supplements for an additional 20-22 h. After culture, cumulus cells were removed and a proportion of oocytes fixed to examine the rate of nuclear maturation. The remaining oocytes were co-incubated with spermatozoa for 5-6 h and putative zygotes were transferred to NCSU 23 medium containing 0.4% bovine serum albumin for 144 h. A proportion of putative zygotes were fixed 12 h after insemination to examine fertilisation parameters. In experiment 2, oocytes were matured as in experiment 1 and the GSH content was measured by a DTNB-GSSG reductase recycling assay. No mean differences among treatments were observed in nuclear maturation (78-89%). The mean differences in penetration rate (69-77%), polyspermy rate (31-40%), male pronuclear formation rate (93-96%) or mean number of sperm per oocyte (1.5-1.8) were not affected by the presence or absence of cysteine during oocyte maturation. Also no difference was observed in cleavage rates 48 h after insemination. However, compared with no addition (19%), the presence of 0.1-0.4 mg/ml cysteine during IVM increased (p < 0.001) the proportion of blastocysts (32-39%) at 144 h. In comparison with controls (5.6 pmol/oocyte), the GSH content of oocytes matured in the presence of cysteine was significantly (p < 0.001) higher (13-15 pmol/oocyte) with no mean differences among different cysteine concentrations. The results indicate that in the presence of a thiol compound, supplementation of IVM medium with cysteine can increase the GSH level and improve the developmental competence of pig oocytes following fertilisation. Further, no effect on either GSH level or embryo development was observed by increasing the levels of cysteine supplementation from 0.1 to 0.4 mg/ml.

Bicarbonate - sensitive cysteine induced elevation of extra cellular aspartate and glutamate in rat hippocampus in vitro

The effect of different concentrations of cysteine (0.125, 0.25, 0.5 and 1 mM) on the net efflux of endogenous amino acids was studied by the incubation of rat hippocampal slices. Addition of cysteine (1 mM) in bicarbonate containing low K + medium (5 min) selectively increased the basal net efflux of glutamate and aspartate by 370% and 396%, respectively. High K + media (50 mM) containing cysteine (1 mM) evoked the net efflux of glutamate and aspartate by 1 454% and 1 019%, respectively. The corresponding effects in control slices without cysteine were 669% and 404%, respectively. No changes were observed on the concentrations of GABA, glutamine and taurine. The cysteine oxidation products, cysteine sulfinate (0.5 μM) and cystine (0.25 mM) were without effects. The effect of cysteine (0.5 mM) was dramatically reduced in media with no added bicarbonate/CO 2. Thus, cysteine in a bicarbonate-sensitive manner selectively increases the extracellular concentration of excitotoxic amino acids in adult rat brain in vitro, possibly by interfering with the carrier-mediated glutamate uptake/ release.

Effect of Vitamins on Microbial Production of Citric Acid by Aspergillus niger

The effect of different concentrations of ascorbic acid, biotin, p-aminobenzoic acid (PABA), riboflavin and thiamine on the growth and activity of Aspergillus niger strain AL 29 was studied at different incubation periods. It was observed that ascorbic acid and PABA inhibited the growth and activity of the mould, while the presence of thiamine and riboflavin stimulated the citric acid formation to the extent of 59.09% and 50.36%, respectively. However, biotin was found to be most suitable for increasing the mycelial growth and also enhancing the production of citric acid (66.4%).

Effect of Amino Acids on Microbial Production of Citric Acid by Aspergillus niger

The effect of different concentrations of cysteine, serine, lysine, aspartic acid, and glutamic acid on the growth and fermenting activity of Aspergillus niger AL 29 was studied at different incubation periods. It was observed that the presence of glutamic acid and aspartic acid stimulated the citric acid production to the extent of 79.6% and 76.7%, respectively. Lysine was effective in producing citric acid by 62%. However, serine could not influence the yield (50.4%) to a greater extent, while the effect of cysteine was found to be detrimental. The yield of citric acid was determined on sugar consumption basis.