Evidence for the Participation of a 5-Oxo-prolinase in Degradation of Glutathione in Nicotiana tabacum

1980 ◽  
Vol 35 (9-10) ◽  
pp. 708-711 ◽  
Author(s):  
Heinz Rennenberg ◽  
Reinhard Steinkamp ◽  
Andrea Polle
Keyword(s):  
Nicotiana Tabacum ◽  
Glutamic Acid ◽  
Suspension Cultures ◽  
Sulfur Source ◽  
Tobacco Cells ◽  
Tobacco Suspension Cultures

Abstract During degradation of glutathione in tobacco suspension cultures substancial amounts of 5-oxo-proline are formed in vivo as well as in crude cell homogenates in vitro. The existance of a 5-oxo-prolinase that catalyzes the conversion of 5-oxo-proline to glutamic acid was demonstrated in tobacco cells, grown with glutathione as sole sulfur source.

scholarly journals Properties of tobacco (Nicotiana tabacum) cadmium-binding peptide(s). Unique non-metallothionein cadmium ligands

1987 ◽  
Vol 241 (3) ◽  
pp. 641-647 ◽  
Author(s):  
R N Reese ◽  
G J Wagner
Keyword(s):  
Nicotiana Tabacum ◽  
Metal Binding ◽  
Tobacco Cells ◽  
Binding Peptide ◽  
Metal Affinity ◽  
Wide Range ◽  
Binding Peptides ◽  
The Common

The chemical and physical characteristics of Cd-binding peptides isolated from tobacco (Nicotiana tabacum) leaves and suspension-cultured tobacco cells were determined and compared with properties of rat liver Cd, Zn-thionein. Some emphasis was placed on metal-binding and specificity properties. Cd-peptides of apparent Mr 6000 and 2000 were induced in tobacco leaves by growth of plants with 90 microM-Cd. Only the apparent-Mr-2000 Cd-peptide was induced in the leaves of tobacco plants grown in the presence of 3 microM-Cd. In cultured tobacco cells exposed to a wide range of Cd levels (3-180 microM), a peptide of apparent Mr 2000 was observed. Under denaturing conditions [6 M-guanidinium chloride (GdmCl) with or without 100 mM-2-mercaptoethanol], all of the above forms were shown to have an Mr of approx. 1300, compared with an Mr of 6000 for Cd, Zn-thionein. The apparent disaggregation of the Mr-6000 form by GdmCl to what appears to be the unit Cd-binding peptide was reversible. Tobacco-derived Cd-peptide contained approx. 40, 35 and 15 residues of glutamate/glutamine, cysteine and glycine respectively, with serine, lysine, and aromatic residues being absent. Tobacco Cd-peptide had an isoelectric point (pI) of 3.15, which is lower than the pI greater than or equal to 4 reported for metallothionein. A 50% dissociation of Cd occurred at pH 5 and 3.5 for the tobacco Cd-peptide and Cd, Zn-thionein respectively, and GdmCl was shown to cause Cd dissociation from tobacco peptide, but not from metallothionein. No evidence was obtained for Zn induction in vivo of, or Zn binding in vitro to, tobacco Cd-peptide. Copper induced a low-Mr metal-binding component in cultured tobacco cells which did not appear to be identical with the peptide induced by Cd. Properties of tobacco Cd-peptide and Cd, Zn-thionein, including metal affinity and selectivity, are greatly different, except for the common presence of 30 residues of cysteine/100 residues.

Effects of ʟ-Methionine-S-sulfoximine on Growth and Glutathione Synthesis in Tobacco Suspension Cultures

1980 ◽  
Vol 35 (11-12) ◽  
pp. 945-951 ◽  
Author(s):  
Heinz Rennenberg ◽  
Rolf Uthemann
Keyword(s):  
Amino Acids ◽  
Suspension Cultures ◽  
Methionine Sulfoximine ◽  
Sole Nitrogen Source ◽  
Animal Cells ◽  
Similar Extent ◽  
Tobacco Cells ◽  
Show Evidence ◽  
Tobacco Suspension Cultures

Abstract Tobacco cells grown photoheterotrophically with high ammonium and sulfate concentrations are able to cope with small amounts of methionine-sulfoximine. The observed methionine-sulfoximine tolerance of tobacco suspensions is due to an extracellular glutathione and an intra­ cellular glutamine reservoir, both reservoirs are considerably reduced by treatment with methionine-sulfoximine concentrations that do not affect the growth of the cells. In tobacco suspension cultures grown with nitrate as sole nitrogen source that do not contain high amounts of glutathione and glutamine, growth inhibition by methionine-sulfoximine can be prevented by addition of these substances to the growth medium. These data indicate that synthesis of glutathione and glutamine are both inhibited by mentionine-sulfoximine; furthermore they show evidence that - in contrary to animal cells -the whole glutathione molecule is taken up by tobacco cells. Synthesis of glutathione from the consisting amino acids is inhibited by methionine-sulfoximine in crude cell homogenates to a similar extent than observed in tobacco suspensions in vivo; therefore, the activity, and not the amount of enzymes of glutathione syn­ thesis seems to be reduced by treatment with methionine-sulfoximine. As tobacco suspensions are able to recover from methionine-sulfoximine treatment with respect to accumulation of glutathione in the medium as well as with respect to growth, detoxication of methionine-sulf­ oximine has to be assumed.

Über den Abbau von Flavonolen in pflanzlichen Zellsuspensionskulturen / Degradation of Flavonols in Plant Suspension Cultures

1972 ◽  
Vol 27 (8) ◽  
pp. 946-954 ◽  
Author(s):  
Wolfgang Hösel ◽  
Paul D. Shaw ◽  
Wolfgang Barz
Keyword(s):  
Salicylic Acid ◽  
Glycine Max ◽  
Cell Suspension ◽  
Cicer Arietinum ◽  
Cell Suspension Cultures ◽  
Suspension Cultures ◽  
Enzyme Preparations ◽  
Cicer Arietinum L

The flavonols kaempferol, quercetin and isorhamnetin were labelled with 14C by keeping seven day old Cicer arietinum L. plants in an atmosphere of 14CO2 for five days. The purified (U-14C) flavonols were applied to cell suspension cultures of Cicer arietinum L., Phaseolus aureus Roxb., Glycine max and Petroselinum hortense. Based on the rates of 14CO2 formation and distribution of radioactivity after fractionation of the cells, the flavonols were shown to be catabolized to a very high extent.All four cell suspension cultures possess the enzymatic activity transforming flavonols to the recently discovered 2,3-dihydroxyflavanones. Upon incubation of the flavonols datiscetin and kaempferol with enzyme preparations from Cicer arietinum L. cell suspension cultures, it was demonstrated that the enzymatically formed 2,3-dihydroxyflavanones are further transformed in an enzyme catalyzed reaction. Salicylic acid was found as a degradation fragment of ring B of the 2,3,5,7,2′-pentahydroxyflavanone derived from datiscetin. Neither phloroglucinol nor phloroglucinol carboxylic acid were observed as metabolites of ring A. These in vitro findings were further substantiated by in vivo data because the flavonols kaempferol, quercetin and datiscetin when applied to cell suspension cultures of Cicer arietinum L. and Glycine max gave rise to para-hydroxybenzoic acid, protocatechuic acid and salicylic acid, respectively. It was thus concluded that flavonols are catabolized via 2,3-dihydroxyflavanones with the B-ring liberated as the respective benzoic acid. The data are discussed in connection with earlier findings on the catabolism of chalcones, cinnamic and benzoic acids.

scholarly journals Fabrication of highly fluorescent graphene quantum dots using l-glutamic acid for in vitro/in vivo imaging and sensing

2013 ◽  
Vol 1 (31) ◽  
pp. 4676 ◽  
Author(s):  
Xu Wu ◽  
Fei Tian ◽  
Wenxue Wang ◽  
Jiao Chen ◽  
Min Wu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Glutamic Acid ◽  
In Vivo Imaging ◽  
Graphene Quantum Dots

scholarly journals Immunosuppressive factor(s) specific for L-glutamic acid(50)-L- tyrosine(50) (GT). II. Presence of I-J determinants on the GT-suppressive factor

1977 ◽  
Vol 146 (1) ◽  
pp. 287-292 ◽  
Author(s):  
J Theze ◽  
C Waltenbaugh ◽  
ME Dorf ◽  
B Benacerraf
Keyword(s):  
T Cells ◽  
Glutamic Acid ◽  
Inbred Mouse ◽  
Inbred Mouse Strain ◽  
Antibody Responses ◽  
Mouse Strains ◽  
Suppressor T Cells ◽  
Suppressor Factor

The responses to the synthetic antigens, L-glutamic acid(60)-L- alanine(30)-L-tyrosine(10) (GAT) and L-glutamic acid(50)-L-tyrosine(50) (GT) are controlled by genes in the I region of the mouse H-2 complex (1-3). Preimmunization of the mice bearing the H-2(p,q,s) nonresponder haplotypes with GAT stimulates the development of suppressor T cells that inhibit in vivo or in vitro antibody responses to GAT complexed to the immunogenic carrier, methylated bovine serum albumin (GAT-MBSA) (4). The copolymer GT is not immunogenic in any inbred mouse strain tested, and has a suppressive effect on the antibody responses to GT-MBSA in mouse strains bearing the H-2(d,f,k,s) haplotypes; suppressor T cells have been demonstrated to be responsible for specific GT suppression (3). We have obtained specific suppressive extracts from thymus and spleen cells of GAT-or GT-primed suppressor strains (5,6). The specific suppressive T-cell factors in the active extracts have been characterized (6,7) and appear similar to the carrier-specific suppressor factor described by Tada and Taniguchi (8). These products belong to a family of newly identified molecules coded for by the I region of the H-2 complex with affinity for antigen and helper (9,10) or suppressive (5-8) regulatory activity on the immune response. Recently, Tada et al. have reported that the keyhole limpet hemocyanin (KLH)-specific suppressor factor is coded for by the I-J subregion of the H-2 complex (11). We now demonstrate also that a GT-specific suppressor factor extracted from the spleens and thymuses of B10.BR (H-2(k)) mice bears determinants controlled by the I-J subregion of the H-2 complex.

scholarly journals The role of malate in the synthesis of glutamate in Pisum arvense roots

2014 ◽  
Vol 55 (4) ◽  
pp. 611-619
Author(s):  
Genowefa Kubik-Dorosz
Keyword(s):  
Glutamic Acid ◽  
Malic Acid ◽  
Glutamate Synthase ◽  
Acid Synthesis ◽  
Incubation Mixture ◽  
Pyridine Nucleotides ◽  
Pisum Arvense

The in vivo and in vitro activities of NADH-dependent glutamate synthase in excised <em>Pisum arvense</em> roots increased several-fold under the influence of malate while pyruvate oxaloacctate. citrate and succinate inhibited this entyme. The plastids isolated from <em>Pisum arvense</em> root,. ahen incubated with glutamine and α-ketoglutarate, released glutamate into the medium Malate clearly stimulated this process. Albizziin (25 mM) completely reduced the presence of glutamate in the incubation mixture. These results indicate that reduced pyridine nucleotides arising in <em>P. arvense</em> root plastids during oxidation of malic acid may constitute the indispensable source of electrons for glutamic acid synthesis.

scholarly journals The Bio-Tribological Effect of Poly-Gamma-Glutamic Acid in the Lysozyme-Ionic Contact Lens System

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 156
Author(s):  
Chen-Ying Su ◽  
Lung-Kun Yeh ◽  
Chi-Chun Lai ◽  
Mihaela Dubuisson ◽  
Yi-Fei Tsao ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Glutamic Acid ◽  
Contact Lens ◽  
Contact Lenses ◽  
Lens System ◽  
Friction Testing ◽  
Lubricating Property ◽  
Velocity Variations

Feeling comfortable is an important issue for contact lens wearers as contact lenses are worn for an extensive period of time. It has been shown that the in vitro friction coefficient of contact lenses is correlated to the degree of in vivo comfort, thus many studies focus on establishing friction testing methods for investigating the friction coefficient of contact lenses or contact lens care solution. We have previously demonstrated the lubricating property of poly-gamma-glutamic acid (γ-PGA)-containing care solution, and it could reduce the high friction coefficient caused by lysozyme. However, the mechanism of how γ-PGA-containing care solution reduces the lysozyme-induced friction coefficient of contact lenses is unclear. We investigated the bio-tribological effect of γ-PGA on ionic contact lenses in the presence of lysozyme by testing load and velocity variations. The ability to remove lysozyme deposition by γ-PGA and viscosity analysis of γ-PGA-containing care solutions were also investigated to understand the potential mechanism. Our results showed that the friction coefficient of γ-PGA-containing care solution with lysozyme was the lowest in both load and velocity variations, and γ-PGA functions distinctly in the lysozyme-ionic contact lens system. We proposed a model of how γ-PGA could reduce the friction coefficient in these two conditions.

scholarly journals Tetrastigma hemsleyanum Vine Flavone Ameliorates Glutamic Acid-Induced Neurotoxicity via MAPK Pathways

2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
Qiang Chu ◽  
Yonglu Li ◽  
Zheng Hua ◽  
Yaxuan Wang ◽  
Xin Yu ◽  
...  
Keyword(s):  
Glutamic Acid ◽  
Neuroprotective Effects ◽  
Tetrastigma Hemsleyanum ◽  
Positive Effects ◽  
Caffeoylquinic Acid ◽  
Mapk Pathways ◽  
Athletic Ability ◽  
Medicinal Value

Glutamic acid (Glu) is a worldwide flavor enhancer with various positive effects. However, Glu-induced neurotoxicity has been reported less. Tetrastigma hemsleyanum (TH), a rare herbal plant in China, possesses high medicinal value. More studies paid attention to tuber of TH whereas vine part (THV) attracts fewer focus. In this study, we extracted and purified flavones from THV (THVF), and UPLC-TOF/MS showed THVF was consisted of 3-caffeoylquinic acid, 5-caffeoylquinic acid, quercetin-3-O-rutinoside, and kaempferol-3-O-rutinoside. In vitro, Glu caused severe cytotoxicity, genotoxicity, mitochondrial dysfunction, and oxidative damage to rat phaeochromocytoma (PC12) cells. Conversely, THVF attenuated Glu-induced toxicity via MAPK pathways. In vivo, the neurotoxicity triggered by Glu restrained the athletic ability in Caenorhabditis elegans (C. elegans). The treatment of THVF reversed the situation induced by Glu. In a word, Glu could cause neurotoxicity and THVF owns potential neuroprotective effects both in vitro and in vivo via MAPK pathways.

scholarly journals Glucosylation of Salicylic Acid in Nicotiana tabacum Cv. Xanthi-nc

1998 ◽  
Vol 88 (7) ◽  
pp. 692-697 ◽  
Author(s):  
Hyung-il Lee ◽  
Ilya Raskin
Keyword(s):  
Salicylic Acid ◽  
Nicotiana Tabacum ◽  
Pseudomonas Syringae ◽  
Gel Filtration ◽  
High Concentration ◽  
Maximal Level ◽  
Minor Metabolite ◽  
Continuous Accumulation

Salicylic acid (SA) is a key regulatory component of disease resistance in plants. In tobacco mosaic virus (TMV)-inoculated tobacco (Nicotiana tabacum cv. Xanthi-nc NN genotype), newly synthesized SA is converted primarily to SA 2-O-β-D-glucoside (SAG) and glucosyl salicylate (GS), a relatively minor metabolite. Similar patterns in the formation of GS and SAG were observed in tobacco inoculated with Pseudomonas syringae pv. phaseolicola, suggesting the accumulation of two glucosylated metabolites is a general phenomenon in tobacco plants. After SA infiltration, GS was synthesized rapidly, reached a maximal level at 6 h, declined, and remained relatively constant for at least 24 h. In contrast, SAG content increased gradually after SA treatment. Our in vitro and in vivo data suggest that a high concentration of free SA triggers transient formation of GS and continuous accumulation of SAG, which is a more stable metabolite of SA. The two distinct SA glucosyltransferases catalyzed the formation of GS and SAG, respectively. The activities of these enzymes were enhanced by TMV or P. syringae pv. phaseolicola inoculation or SA treatment and were found in different fractions of gel filtration chromatography.

Sign in / Sign up

Export Citation Format

Share Document