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At least 19 recordsLinked to original sources
PubMed1979

Toxicology of the sulfur oxides.

Continuing interest by OSHA-NIOSH and by EPA regarding the adequacy of current sulfur oxides standards has prompted a reappraisal of the available human and animal data. Results of animals studies were not considered to be useful in establishing the original air quality standards in 1970, even though there was good reason to consider them as a prime source of information. Considering the multitude of species tested, using every conceivable method of administration and range of doses, a fairly consistent pattern of effect has emerged. Further, the majority of the human clinical data and even the industrial data parallel and support the results found in the animal studies. However, neither the animal studies, the clinical investigations nor the industrial experiences agree with the recently reported community epidemiological studies that are currently receiving attention. It may well be that the toxicological data are correct in that there are no important long-term effects from exposure to the sulfur oxides. Certainly the laboratory studies, animal or human, do not support more stringent standards for either the occupational or the community environment.

Air Pollutants↗
PubMed1976

Inhibition of growth, iron, and sulfur oxidation in Thiobacillus ferrooxidans by simple organic compounds.

Iron and sulfur oxidation by Thiobacillus ferrooxidans as well as growth on ferrous iron were inhibited by a variety of low molecular weight organic compounds. The influences of chemical structure of the organic inhibitors, pH, temperature, physical treatment of cells, and added inhibitory or stimulatory inorganic ions and iron oxidation suggest that a major factor contributing to the inhibitory effects on iron oxidation is the relative electronegativity of the organic molecule. The data also suggest that inhibitory organic compounds may (i) directly affect the iron-oxidizing enzyme system, (ii) react abiologically with ferrous iron outside the cell, (iii) interfere with the roles of phosphate and sulfate in iron oxidation, and (iv) nonselectively disrupt the cell envelope or membrane.

Acids↗
PubMed1978

Effect of sulfur application on sulfur-oxidizing bacteria and yield of two leguminous crops.

The effect of elemental sulfur application at the rate of 50, 100, 200, and 400 kg/feddan on broad-bean and lentil was tested in field experiments. Sulfur application resulted in increasing the numbers of the autotrophic sulfur-oxidizing bacteria as well as in the concentration of available sulfate in the soil; the increases were proportional to the level of sulfur added. The sulfur treatments neither affected the soil pH nor the nodulation of the leguminous plants tested. The application of sulfur at the rates used slightly increased seed yield and nitrogen content of lentil seeds, but had no effect on broadbean.

Fabaceae↗
PubMed1976

Rate of elemental sulfur oxidation in some soils of Egypt as affected by the salinity level, moisture, texture, temperature and inoculation.

1. The level of soil moisture most favourable to the oxidation of elemental sulfur was found to be around the field moisture capacity; the oxidation rate decreased at lower and higher moisture levels. 2. The rate of oxidation increased with the clay content of the soils from sandy loam to clay loam. 3. Although S-oxidation could be found already at 10 degrees C, it increased markedly up to a maximum at 35 degrees C and then decreased again at higher temperatures. 4. Increasing the salt content of the soil (NaCl) reduced the rate of oxidation up to a concentration of 9 g salt/100 g soil; at a concentration of salt of 11 g/100 g soil no S-oxidation occurred. 5. Inoculation of the soil with Thiobacillus thiooxidans accelerated the S-oxidation, especially when organic matter was added. 6. In all experiments, S-oxidation was accompained by a decrease in pH.

Acidithiobacillus thiooxidans↗
PubMed1977

Availability of oxidized sulfur amino acids for the growing chick.

In four trials, experimental diets were fed to one week old broiler cockerels for a period of 14 days to compare the availability of oxidized sulfur amino acids to DL-methionine on an equimolar basis. The data were analyzed by the slope-ratio technique. Chick weight gain per unit feed consumed was the dependent variable and dietary level of supplemental amino acid was the independent variable. There was no significant (P=.05) differences in availability of DL-, L-, and D-methionine. D-, DL-, and L-methionine sulfoxide were 52, 59 and 77%, respectively, as available as DL-methionine. The differences in availability between the three sulfoxides and DL-methionine were significant. Both DL- and D-methionine sulfoxide were significantly less available than L-methionine sulfoxide. No response was obtained from L-cysteic acid or DL-methionine sulfone.

Amino Acids, Sulfur↗
PubMed1977

Stereospecific sulfur oxidation of 7-methylthioxanthone-2-carboxylic acid by Calonectria decora.

Thin-layer chromatography was used to determine the ability of three microorganisms capable of sulfur oxygenation, including Aspergillus niger, Streptomyces armentosus subsp. armentosus, and Calonectria decora, to oxidize 7-methylthioxanthone-2-carboxylic acid to the corresponding sulfoxide in growing cultures. In addition, optical rotary dispersion, circular dichroism, and nuclear magnetic resonance analysis in the presence of chiral shift reagent were used variously to access reaction stereoselectivity, absolute configuration, and optical purity of isolated products. The data indicated that C. decora produced the sulfoxide in high yield (69%) and optical purity (97%), most probably in the S-configuration.

Aspergillus niger↗
PubMed1979

Effects of sulfur oxides and respirable particles on human health. Methodology and demography of populations in study.

As part of a study of health effects of sulfur dioxide and particulate matter, we have established a cohort of adults 25 to 74 yr of age in 6 communities who will be followed prospectively. At the conclusion of our first cycle of measuring the health of adults in 6 sites we found that, although we used different sampling frames, our samples were close to the distribution shown in the U.S. Census for age, sex, and occupation, with the possible exception of one city. Analysis of the cross-sectional data indicated that for both age- and height-adjusted values for forced expiratory volume in 1 s and for selected rates of various respiratory symptoms standardized for age, differences among smoking groups were apparent. Differences in these parameters between sites suggest trends that were associated with levels of pollution. Further analyses of the prospective data currently being collected will be required before definitive statements can be made about the effect of specific levels of exposure.

Adult↗
PubMed1975

Purification and some properties of cytochrome c-552 from a sulfur-oxidizing bacterium, Thiobacillus thiooxidans.

A soluble cytochrome c-552 from Thiobacillus thiooxidans was highly purified and its physico-chemical properteis were studied. The absorption maxima were at 552,523,418 nm in the reduced from and at 412 nm in the oxidized form. The pyridine hemochrome spectrum was the same as that of other cytochromes c. The molecular weight, estimated by the gel filtration method, was found to be 12,600. The isoelectric point was determined to be 9.2-9.3 by the electrofocusing technique. The standard oxidation-reduction potential of this cytochrome was +0.247 V.

Acidithiobacillus thiooxidans↗
PubMed1979

Purification of a reconstitutively active iron-sulfur protein (oxidation factor) from succinate . cytochrome c reductase complex of bovine heart mitochondria.

Oxidation factor, a protein required for electron transfer from succinate to cytochrome c in the mitochondrial respiratory chain, has been purified from isolated succinate . cytochrome c reductase complex. Purification of the protein has been followed by a reconstitution assay in which restoration of ubiquinol . cytochrome c reductase activity is proportional to the amount of oxidation factor added back to depleted reductase complex. The purified protein is a homogeneous polypeptide on acrylamide gel electrophoresis in sodium dodecyl sulfate and migrates with an apparent Mr = 24,500. Purified oxidation factor restores succinate . cytochrome c reductase and ubiquinol . cytochrome c reductase activities to depleted reductase complex. It is not required for succinate dehydrogenase nor for succinate . ubiquinone reductase activities of the reconstituted reductase complex. Oxidation factor co-electrophoreses with the iron-sulfur protein polypeptide of ubiquinol . cytochrome c reductase complex. The purified protein contains 56 nmol of nonheme iron and 36 nmol of acid-labile sulfide/mg of protein and possesses an EPR spectrum with the characteristic "g = 1.90" signal identical to that of the iron-sulfur protein of the cytochrome b . c1 complex. In addition, the optimal conditions for extraction of oxidation factor, including reduction with hydrosulfite and treatment of the b . c1 complex with antimycin, are identical to those which facilitate extraction of the iron-sulfur protein from the b . c1 complex. These results indicate that oxidation factor is a reconstitutively active form of the iron-sulfur protein of the cytochrome b . c1 complex first discovered by Rieske and co-workers (Rieske, J.S., Maclennan, D.H., and Coleman, R. (1964) Biochem. Biophys. Res. Commun. 15, 338-344) and thus demonstrate that this iron-sulfur protein is required for electron transfer from ubiquinol to cytochrome c in the mitochondrial respiratory chain.

Animals↗
PubMed2026

Proteobacteria with chemosynthetic potential are highly prevalent in the gills of Hypoplectrus reef fishes.

Fishes host a diverse microbiome in their gills, but a broad characterization of this microbiome at the metagenomic level is lacking. Here, we apply genome-resolved metagenomics to the gills of the hamlets (Hypoplectrus spp), a group of reef fishes from the Greater Caribbean. The analysis of 353 gill samples from 15 hamlet species collected at eight locations over 13 years revealed a stark contrast between the gill microbiota and reef water microbial communities, indicating a distinct and specific gill microbiome. A total of 70 gill-associated metagenome-assembled genomes (MAGs) were recovered. These MAGs belong to 17 lineages, most of which are novel. They relate to known fish gill pathogens, fish gut microbes, free-living and biofilm-associated taxa, indicating that the gill microbiome was assembled from a collection of distinct eco-evolutionary trajectories. The MAGs harbor diverse metabolic modules, involved notably in nitrogen cycling, antibiotic production and biofilm formation, revealing a highly dynamic microbial ecosystem. One lineage in the Burkholderiaceae family was outstandingly prevalent across fish host species, sampling locations and years. Its genome encoded complete metabolic modules for carbon fixation and sulfur oxidation, indicating chemosynthetic potential. To the best of our knowledge, this is the first line of evidence that fishes may host sulfur-oxidizing chemosynthetic bacteria in their gills. The functional significance of this chemosynthetic potential for the fish host or other members of the gill microbiome remains to be established. The high prevalence of this lineage allowed to build a pangenome. It revealed large-scale geographic structure (western Caribbean, eastern Caribbean and Gulf of Mexico), which parallels the phylogenomic pattern observed in the hamlets. Overall, our findings point to complex fish host-microbe and microbe-microbe eco-evolutionary interactions in the gills that may influence fish physiology, homeostasis and immune response.

Animals↗
PubMed1975

Ambient air pollutant analyses-integral part of an environmental impact study.

Data for the major pollutants; carbon monoxide, nitrogen oxides, photochemical oxidants, suspended particulates, and total hydrocarbons, have been presented. In addition, lead analysis and a justification for no sulfur oxides data are also discussed. This study was an integral part of an Environmental Impact Study carried out by the Chemistry Department and the Institute of Transportation Studies a Villanova University. Some of the pollutants were found to cause a situation of concern; namely, photochemical oxidants, suspended particulates and nitrogen oxides. On the otherhand, carbon monoxide and total hydrocarbons were found to be well below limits set by the EPA. Although no standards are set for lead in ambient air, the data showed very low concentrations of this pollutant in our particulate samples. Since oxides ofsulfur are more an industrial, rather than transportation, pollutant little relevance could have been found for the type of study performed.

Air Pollution↗