Effect of Variable Sulfur Supply on Thiol Compounds and Arsenic Accumulation in Kandelia Obovata (S., L.) Yong Seedlings

The transcriptional regulators of arsenic-induced gene expression remain largely unknown; however, arsenic exposure rapidly depletes cellular glutathione levels increasing demand for thiol compounds from the sulfur assimilation pathway. Thus, sulfur assimilation is tightly linked with arsenic detoxification. To explore the hypothesis that the key transcriptional regulator of sulfur assimilation, SLIM1, is involved in arsenic-induced gene expression, we evaluated the response of slim1 mutants to arsenic treatments. We found that slim1 mutants were sensitive to arsenic in root growth assays. Furthermore, arsenic treatment caused high levels of oxidative stress in the slim1 mutants, and slim1 mutants were impaired in both thiol and sulfate accumulation. We also found enhanced arsenic accumulation in the roots of slim1 mutants. Furthermore, microarray analyses identified genes from a highly co-regulated gene cluster (the O-acetylserine gene cluster), as being significantly upregulated in the slim1-1 mutant background in response to arsenic exposure. The present study identified the SLIM1 transcription factor as an important component in arsenic-induced gene expression and arsenic tolerance. Our results suggest that the severe arsenic sensitivity of the slim1 mutants is a result of both altered redox status as well as mis-regulation of key genes.

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Excessive sulfur supply reduces arsenic accumulation in brown rice

Plant Soil and Environment ◽

10.17221/882/2012-pse ◽

2013 ◽

Vol 59 (No. 4) ◽

pp. 169-174 ◽

Cited By ~ 24

Author(s):

J. Fan ◽

X. Xia ◽

Z. Hu ◽

N. Ziadi ◽

C. Liu

Keyword(s):

Contaminated Soils ◽

Rice Yield ◽

Brown Rice ◽

Translocation Factor ◽

Plaque Formation ◽

Iron Plaque ◽

Arsenic Accumulation ◽

Sulfur Supply ◽

Rice Leaves ◽

As Stress

The objective of this study was to investigate the influence of excessive sulfur (S) supply on iron plaque formation and arsenic (As) accumulation in rice plants. A combined soil-sand pot experiment was conducted by using two As levels (0, 20 mg/kg) combined with three S concentrations (0, 60, 120 mg/kg). The results showed that excessive S supply significantly decreased As concentration in brown rice, but As concentration in root increased with increasing rate of S supply. Moreover, bioconcentration factors for leaves and stems were 8–35 fold of that for brown rice, indicating that As was mainly accumulated in rice leaves and stems instead of brown rice. Furthermore, excessive S supply significantly decreased translocation factor of As compared to treatment without S supply. These results indicated that excessive S may reduce As translocation from soils and roots to grain. The mechanism could be ascribed to excessive S that induced the decrease of As availability, the increase of iron plaque formation under As stress, and the increase of glutathione in rice leaves and roots. Therefore, excessive S can reduce As accumulation in brown rice exposed to As contaminated soils though it may result in loss of rice yield.

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The Reaction of Thiol Compounds with the Vitamin-K Dependent Clotting Factors

Thrombosis and Haemostasis ◽

10.1055/s-0038-1653570 ◽

1969 ◽

Vol 21 (03) ◽

pp. 573-579 ◽

Cited By ~ 1

Author(s):

P Fantl

Keyword(s):

Prothrombin Time ◽

Vitamin K ◽

Anaerobic Conditions ◽

Clotting Factors ◽

Thiol Compounds ◽

Aerobic Conditions ◽

One Stage ◽

Factor Ii ◽

Ph Dependent ◽

The One

SummaryTreatment of human and dog oxalated plasma with 0.2 to 1.0 × 10−1 M 2.3-dithiopropanol (BAL) or dithiothreitol (DTT) at 2–4° C for 30 min results in the reduction of the vitamin-K dependent clotting factors II, VII, IX and X to the respective-SH derivatives. The reaction is pH dependent. Under aerobic conditions the delayed one stage prothrombin time can be partly reversed. Under anaerobic conditions a gradual prolongation of the one stage prothrombin time occurs without reversal.In very diluted plasma treated with the dithiols, prothrombin can be converted into thrombin if serum as source of active factors VII and X is added. In contrast SH factors VII, IX and X are inactive in the specific tests. Reoxidation to active factors II, VII, IX and X takes place during adsorption and elution of the SH derivatives. The experiments have indicated that not only factor II but also factors VII, IX and X have active-S-S-centres.

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Influence of the lipoic acid on the regenerative potential of thiol compounds in the retina in modeling age maculodystrophy in animals with allergic uveitis

Oftalmologicheskii Zhurnal ◽

10.31288/oftalmolzh201417480 ◽

2014 ◽

Vol 47 (1) ◽

pp. 74-80

Author(s):

V. Savko ◽

◽

Vashah Zijad Mahmud Ahmed ◽

Keyword(s):

Lipoic Acid ◽

Thiol Compounds

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Post-proline endopeptidase, further characterization of the enzyme from pig kidneys

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19841846 ◽

1984 ◽

Vol 49 (8) ◽

pp. 1846-1853 ◽

Cited By ~ 4

Author(s):

Karel Hauzer ◽

Tomislav Barth ◽

Linda Servítová ◽

Karel Jošt

Keyword(s):

Amino Acids ◽

Aspartic Acid ◽

Ion Exchange Chromatography ◽

Exchange Chromatography ◽

Relative Molecular Mass ◽

Enzyme Molecule ◽

Thiol Compounds ◽

Modified Method ◽

N Terminus

A post-proline endopeptidase (EC 3.4.21.26) was isolated from pig kidneys using a modified method described earlier. The enzyme was further purified by ion exchange chromatography on DEAE-Sephacel. The final product contained about 95% of post-proline endopeptidase. The enzyme molecule consisted of one peptide chain with a relative molecular mass of 65 600 to 70 000, containing a large proportion of acidic and alifatic amino acids (glutamic acid, aspartic acid and leucine) and the N-terminus was formed by aspartic acid or asparagine. In order to prevent losses of enzyme activity, thiol compounds has to be added.

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