Role Of Sulfur Research Articles

Role of sulphur in radioprotective extracts of Micrococcus radiodurans.

A HIGHLY efficient, low molecular weight endogenous radioprotective agent, capable of protecting relatively sensitive strains of bacteria such as E. coli B/r against the lethal effects of X-irradiation, can be extracted from Micrococcus radiodurans1. There was indirect evidence that the protective extract contained a sulphydryl-amine, derived from methionine, similar to mercaptoethylamine (MEA), cystamine or mercaptopropylamine (MPA)1–3. The most effective chemical radioprotective agents found so far are amino-thiols of the general structural formula, R2N—(CH2)n–SH, where R=H+ or NH2 and n is not greater than three. Non-thiol compounds and sulphydryl compounds which digress from the scheme are usually ineffective in bacterial systems4–6. Recent evidence indicates that the radioprotective component in extracts from Micrococcus radiodurans may not be sulphydryl in nature.

RI利用による鉄鋼の硫化物腐食われに関する研究

It has been generally considered that sulfide corrosion cracking of steels is hydrogen embrittlement cracking, but it has not been confirmed clearly. Furthermore, few studies on the behavior of sulfer has been reported.In the present study experiments have been made on the behavior of sulfide in the sulfide corrosion cracking using a radio-isotope of 35S: 80 kg high strength steel, 60 kg high strength steel, APS steel and boiler plate steel were used as specimens. These specimens were immersed in sulfide corrosive solution under stress for a long time. After this treatment, the distributions of 35S in these specimens were investigated by radiometry and an autoradiographic technique.The experimental results are as follows:(1) The more the susceptibility of the specimens to the sulfide corrosion cracking is, the greater the amount of 35S deposit. And 35S diffuses in such specimens more deeply.(2) The distribution of induced crack corresponds almost exactly to that of 35S. Howevre, 35S cannot be detected in some cracks.(3) The influence of stress on the sulfide corrosion cracking was confirmed.(4) It is considered that sulfur diffuses into grain boundaries of steels.It has been conclude that the sulfide corrosion cracking is different from simple hydrogen embrittlement cracking and stress corrosion cracking by anode attacks exerts influence on the sulfide corrosion cracking.From the these points of view, the behavior and the role of sulfur in the sulfide corrosion cracking should be investigated with more keen interest.

Geochemistry of wall-rock alteration and the role of sulfurization in the formation of the Ore Knob sulfide deposit

Chemical analyses of the wall rock gneiss at Ore Knob reveal that iron decreases toward the ore body. Biotite, the principal iron-bearing mineral in the wall rock gneiss, decreases in iron content and abundance toward the ore. Along a given drill core there is a correlation between the percentage of iron in biotite and in the total rock, and the thickness of the ore body; a similar correlation exists between the N (sub gamma ) index of biotite and the thickness of ore.Biotite averages only 8 ppm of copper, and the amount of copper in biotite from drill core samples does not show a significant increase or decrease toward the ore. Chalcopyrite and sulfur, however, increase toward the ore. The distributions of copper and sulfur in the wall rock gneiss support the idea of introduction of these elements from a distant source, whereas the distribution of iron does not support this idea. Calculations indicate that enough iron was removed from the wall rock gneiss to account for all the iron in the ore body. It is suggested that during metamorphism sulfurization was an important ore-forming process at Ore Knob, and that copper and sulfur introduced in hydrothermal solutions combined with iron from the biotite of the wall rock to produce the massive sulfide copper ore body at Ore Knob.

The role of sulphur, sulphide and reducible dyes in the enzymic oxidation of cysteamine to hypotaurine.

1. Cysteamine is oxidized to hypotaurine by an enzyme extracted from horse kidney, with sulphur or sulphide acting as a cofactor. It has been now found that, when the enzyme is omitted, sulphur and sulphide are able to catalyse the oxidation of cysteamine to cystamine by molecular oxygen. 2. Methylene blue may be used in catalytic amounts as a cofactor in the enzymic oxidation of cysteamine to hypotaurine in the place of sulphur or sulphide. The effect of methylene blue is not light-dependent and is not abolished by catalase. Other redox dyes with E'(0) higher than that of methylene blue are also used as cofactors. 3. A property common to all the cofactors is that they are necessary for the enzymic process in catalytic amounts, though they depress the final amount of hypotaurine produced when added over a critical concentration. All the cofactors share also the property of being catalysts for the non-enzymic oxidation of cysteamine to cystamine. 4. Methylene blue is reduced by cysteamine under anaerobic conditions, and is reoxidized in the presence of air. The rate of the reduction is not accelerated by the enzyme, indicating that the dye does not act in this reaction as a hydrogen carrier from the enzyme to oxygen. The possible mechanism of action of methylene blue and of the other cofactors is discussed.

The role of sulfur in peroxide cured ethylene‐propylene rubber

The role of sulfur in peroxide cured ethylene‐propylene rubber

ROLE OF SULFUR IN THE CELL DIVISION OF <italic>CHLORELLA</italic>, WITH SPECIAL REFERENCE TO THE SULFUR COMPOUNDS APPEARING DURING THE PROCESS OF CELL DIVISION. I.

The role of sulfur in the cell division of Chlorella was studied by following the fate of the sulfur supplied to the sulfur-deficient cells using 35S as a tracer. The sulfur-deficient cells which were unable to perform cell division were made capable of division by the provision of 36S-labeled sulfate under non-photosynthesizing conditions. Soon after the provision of sulfate the labeled sulfur went rapidly into the cold perchloric acid (PCA)-soluble fraction of algal cells, almost entirely in the form of sulfate and/or some other inorganic sulfur substance (s). With the lapse of time, more or less remarkable changes occurred in the pattern of 35S-distribution in different fractions of cell material. It was noticed that, at the onset of cell division, a sulfur-containing peptide-nucleotide compound(s) (SPN), which has been reported earlier, appeared in a large quantity in the cold PCA-soluble fraction, and that its quantity decreased gradually during the subsequent process of cell division, suggesting that the compound was transformed into some other substance (s), presumably with its nucleotide moiety going into nucleic acids and the peptide moiety going into some essential proteins. Another noteworthy phenomenon observed during the process of cell division was the incorporation of 36S in a group of hot PCA-soluble substances. These sulfur substances were revealed to be sulfur-containing nucleotidic compounds, which might possibly be some essential components of, or substances in close relation to, deoxypentose nucleic acid (DNA).

A New Role for Sulfur in Higher Plants

A New Role for Sulfur in Higher Plants

Electron Paramagnetic Resonance Observations on Irradiated Thiols and Disulphides

THE unique role of sulphur in radiation damage is amply borne out by recent electron paramagnetic resonance work1–3. In a current investigation on the mechanism of action of the sulphur-containing radio-protective compounds, quantitative electron paramagnetic resonance studies have been carried out on a series of irradiated thiols and disulphides.

Role of sulfur in the cell division of Chlorella, studied by the technique of synchronous culture

1. 1. Chlorella was grown synchronously under controlled supply of S- and N-sources so as to make the processes of nuclear and cellular division proceed stepwise, and by using 35S as a tracer the fates of S-compounds in various fractions of cell material (extracts with 70% ethanol, with 10% trichloroacetic acid, and the residue) were followed. 2. 2. In the cells grown in the normal medium, the S-content (in %) of the ethanol- and TCA-extracts decreased in the growing stage and increased markedly at the ripening stage. 3. 3. The ethanol extract contained an unknown S-compound and a non-S-containing peptide-like substance, the latter substance appearing only at certain stages of cell ripening. When chromatographed on paper the TCA extract gave only 1 radioactive (but ninhydrin-negative) spot, which, on hydrolysis with HCl, turned ninhydrin-positive owing to the liberation of several amino acids including cyst(e)ine. 4. 4. In the cells, whose nuclear and cellular division were controlled by limited supply of S- and N-sources, the quantity of the S-containing substance in the TCA-extract increased markedly before nuclear division, and the unknown non-S-containing substance in the ethanol extract appeared only before and concomitantly with, the occurrence of cellular division.

The role of sulfur in the cell division of chlorella

1. The role of sulfur in the process of cell division of Chlorella was studied using the technique of synchronous culture. When the “dark cells” (smaller and strongly photosynthesizing cells), which had been grown in a normal nutrient medium, were further cultured in an S-deficient medium under photosynthesizing conditions, the cells grew up to some extent, showing about two-fold increase of DNA-content followed by the division of nucleus into two. At this stage, however, the cells fell into a stalemate, being unable to complete cellular division. 2. When such cells were transferred to a medium containing potassium sulfate only, some synthesis of DNA and further division of nuclei occurred. Under non-photosynthesizing conditions, the process of cellular division ensued, giving rise to a formation of small daughter cells. Under photosynthesizing conditions, on the other hand, the cells increased appreciably in size, without, however, being able to perform cellular division. The process of cellular division thus halted could be resumed when the cells were further supplied with nitrate and sulfate under photosynthesizing condition. 3. Based on these observations, it was concluded that sulfur plays, in cooperation with some nitrogenous substance(s), an essential role in the process of DNA-formation and nuclear division as well as in the process of cellular division.

The fate of diphenyl in the rat

1. 1. A study of the fate of diphenyl in the rat has been carried out. 2. 2. Five metabolites, including 4-hydroxydiphenyl, 4-phenylcatechol, 4,4′-dihydroxydiphenyl, diphenylmercapturic acid and p-β- d-glucu-ronosidodiphenyl have been isolated from the urines of these animals. 3. 3. The role of sulfur in the metabolism of aromatic hydrocarbons is discussed.

Role of Sulfur in the Luminescence and Coloration of Some Aluminosilicates

Certain complex, sulfur‐containing sodalite‐type silicates, synthesis of which is described, exhibit under 3650 Å excitation an emission extending from 5000 Å to beyond 7000 Å, the spectrum varying with composition. The band structure of this emission at −196°C is similar to the emission structure shown by a mixture of and . It is concluded that luminescence is due to the presence of , which replaces part of the normally present in sodalite.Synthetic sodalites containing both and are tenebrescent, coloring purple on irradiation with 2537 and 3650 Å ultraviolet.

The role of sulfur in the metabolism of Endamoeba histolytica

The role of sulfur in the metabolism of Endamoeba histolytica

Chemotherapy of Chronic Progressive Arthritis of Mice. I. Role of Sulfur in Gold-Containing Compounds

ConclusionsArthritis of mice, caused by pleuropneumonia-like microorganisms has been treated with gold sodium thiomalate, sodium thiomalate, the disulphicle form of sodium thiomalate and sodium succinimido-aurate. The compounds containing gold, gold sodium thiomalate and sodium succinimido-aurate, were effective in curing this disease, the others had no therapeutic effect. Sulfur alone or in sulfhydryl linkage is not necessary in order that gold-containing compounds have a therapeutic effect.

The hypoglycemic activity of organic sulfur compounds and the role of sulfur in relation to the activity of insulin

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe hypoglycemic activity of organic sulfur compounds and the role of sulfur in relation to the activity of insulinCharles E. Braun , Martha B. Mason , and Constance L. Brown Cite this: J. Chem. Educ. 1938, 15, 6, 261Publication Date (Print):June 1, 1938Publication History Received3 August 2009Published online1 June 1938Published inissue 1 June 1938https://doi.org/10.1021/ed015p261RIGHTS & PERMISSIONSArticle Views31Altmetric-Citations2LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (6 MB) Get e-Alerts Get e-Alerts