Uptake and metabolism of organic compounds by Chlorobium phaeobacteroides isolated from Lake Kinneret

1981 ◽  
Vol 27 (10) ◽  
pp. 1087-1091 ◽  
Author(s):  
T. Bergstein ◽  
Y. Henis ◽  
B. Z. Cavari
Keyword(s):  
Organic Compounds ◽  
Photosynthetic Activity ◽  
Glyoxylic Acid ◽  
The Other ◽  
Organic Substrates ◽  
Acid Cycle ◽  
Acetate Concentration ◽  
Chlorobium Phaeobacteroides ◽  
Cell Fractions ◽  
Uptake And Metabolism

Organic substrates have an important role in Chlorobium phaeobacteroides nutrition, especially under suboptimal light intensities for photosynthetic activity. In addition, increasing acetate concentration in the medium caused a decrease in photosynthetic activity. Approximately 50% of the acetate carbon was retained in the cells, while the other 50% was released as CO2. Acetate carbon and CO2 carbon were assimilated into the same cell fractions. Two key enzymes of the glyoxylic acid cycle were found in Chlorobium cells, indicating that acetate is incorporated via this pathway.

Removal of Trace Metals From Wastewater by Activated Carbon

1973 ◽  
Vol 8 (1) ◽  
pp. 110-121
Author(s):  
A. Netzer ◽  
J.D. Norman
Keyword(s):  
Activated Carbon ◽  
Trace Metals ◽  
Organic Compounds ◽  
The Other ◽  
Published Data ◽  
Ph Adjustment ◽  
Nickel Silver ◽  
Ph Range ◽  
Carbon Treatment ◽  
Cobalt Copper

Abstract The merits of activated carbon for removal of organic compounds from wastewater have been well documented in the literature. On the other hand there is a lack of published data on the use of activated carbon for the removal of trace metals from wastewater. Experiments were designed to assess the possibility that activated carbon treatment would remove aluminum, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, silver and zinc from wastewater. All metals studied were tested over the pH range 3-11. Greater than 99.5% removal was achieved by pH adjustment and activated carbon treatment for most of the metals tested.

The Mode of Action of Disulfide Accelerators of Vulcanization

1937 ◽  
Vol 10 (1) ◽  
pp. 158-163
Author(s):  
W. Langenbeck ◽  
H. C. Rhiem
Keyword(s):  
Organic Compounds ◽  
Mode Of Action ◽  
Common Knowledge ◽  
Inorganic Compounds ◽  
Technical Problem ◽  
The Other ◽  
Rubber Industry ◽  
Organic Catalysis ◽  
Catalytic Power ◽  
Organic Catalysts

Abstract The catalytic power of organic compounds in general has up to the present time been studied much less extensively than that of inorganic compounds. For about the last ten years, however, the first author has, in collaboration with a number of his students, attempted to fill this gap, though so far efforts have been confined to explaining the mode of action of natural enzymes by means of comparative experiments with organic catalysts. As a result of this work, a theory based on experimental facts has been developed to explain in a satisfactory way the action of enzymes. The other phase of organic catalysis is, strictly speaking, a technical problem. Why for instance should it not be practicable to utilize organic catalysts more extensively than heretofore in industry? If this problem is to be attacked, it seems reasonable to start with the particular industry which already uses organic catalysts to the greatest extent. This is, of course, the rubber industry. The important accomplishments of the chemical industry with respect to the development of vulcanization accelerators is already common knowledge, and the important task at present is not simply to increase the great number of accelerators already known. A problem of more practical value would seem to be to study the mechanism of the acceleration of vulcanization, about which relatively little has been known heretofore.

THE ENZYMES OF THE TRICARBOXYLIC ACID CYCLE OF PSEUDOMONAS AERUGINOSA

1956 ◽  
Vol 2 (4) ◽  
pp. 433-440 ◽  
Author(s):  
Jack J. R. Campbell ◽  
Roberts A. Smith
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Malic Acid ◽  
Tricarboxylic Acid Cycle ◽  
Tricarboxylic Acid ◽  
The Other ◽  
Acid Cycle ◽  
High Ph ◽  
Optimum Activity ◽  
Fresh Cell ◽  
Cell Extracts

It was demonstrated that Pseudomonas aeruginosa possesses all the enzymes necessary for the oxidation of pyruvate to CO2 and water without passing through the conventional intermediates oxalosuccinate and α-ketoglutarate. These intermediates are bypassed by the action of the enzyme isocitratase which splits d-isocitrate to succinate plus glyoxylate. This reaction was shown to be readily reversible. The malic acid dehydrogenase content was low and in addition this enzyme required a high pH for optimum activity. In fresh cell extracts at pH 7.4 its activity was only 10% that of the other enzymes of the cycle. The malic and isocitric dehydrogenases were TPN specific. The organism was also shown to possess all the enzymes necessary for the operation of the conventional tricarboxylic acid cycle.

scholarly journals Uptake and Metabolism of Tritiated 17ß-Oestradiol and Oestrone by Rabbit Uterine Tissue in vitro

1974 ◽  
Vol 27 (2) ◽  
pp. 137 ◽  
Author(s):  
RG Gabb ◽  
GM Stone
Keyword(s):  
Nuclear Receptor ◽  
Mode Of Action ◽  
Nuclear Extract ◽  
Lower Proportion ◽  
The Other ◽  
Uterine Tissue ◽  
Uptake And Metabolism

To determine whether the established capability of rabbit uterine tissue to interconvert 17 p-oestradiol and oestrone might have some effect on the mode of action of the oestrogens in this organ, the in vitro interconversion of [3H]-17p-oestradiol and [3H]oestrone by rabbit endometrial and myometrial tissue was investigated and the identity of radiometabolites in 'soluble, 'mitochondrial-microsomal' a'nd 'nuclear' preparations was studied. Both endometrial and myometrial tissue were found to be capable of oxidoreduction of the oestrogens, the equilibrium of the reaction favouring the reduction of oestrone. Irrespective of the tissue--steroid combination studied, the greater part of the radioactivity in all fractions was associated with 17p-oestradiol. The relative proportions of [3Hl-17p-oestradiol and [3H]oestrone varied between fractions, the nuclear preparation consistently showing a lower proportion of oestrone than the other fractions. Sephade<c fractionation of a 0'4M KCl 'nuclear extract' revealed that proportionately less oestrone than 17p-oestradiol was bound to the nuclear 'receptor'. These findings provide further evidence for 17p-oestradiol being the ovarian oestrogen which is active in the uterus, and suggest a role for uterine oxidoreduction of oestrogens in the control exercised over this organ by these steroids.

Microchemical Method for Oxygen

1963 ◽  
Vol 46 (4) ◽  
pp. 559-564
Author(s):  
Al Steyermakk
Keyword(s):  
Organic Compounds ◽  
The Other ◽  
Gravimetric Procedure

Abstract A specific gravimetric procedure was submitted to the collaborators for this year’s study on the determination of oxygen in organic compounds. Three compounds were analyzed: one contained no oxygen, one contained only carbon, hydrogen, and oxygen, and the other was a sulfa compound. The results obtained were good, and the method is recommended as official, first action.

scholarly journals Saturated hydrogen improves lipid metabolism disorders and dysbacteriosis induced by a high-fat diet

2020 ◽  
Vol 245 (6) ◽  
pp. 512-521 ◽  
Author(s):  
Xiangjie Qiu ◽  
Qiaona Ye ◽  
Mengxing Sun ◽  
Lili Wang ◽  
Yurong Tan ◽  
...  
Keyword(s):  
Fatty Acid ◽  
High Fat Diet ◽  
Metabolic Disorders ◽  
Metabolic Diseases ◽  
Isocitrate Lyase ◽  
Intestinal Flora ◽  
Glyoxylic Acid ◽  
Density Lipoprotein ◽  
High Fat ◽  
Acid Cycle

Studies have shown that metabolic diseases, such as obesity, are significantly associated with intestinal flora imbalance. The amplification of opportunistic pathogens induced by the glyoxylic acid cycle contributes to intestinal flora imbalance. Promising, though, is that saturated hydrogen can effectively improve the occurrence and development of metabolic diseases, such as obesity. However, the specific mechanism of how saturated hydrogen operates is still not very clear. In this study, after a high-fat diet, the level of total cholesterol, total glyceride, and low-density lipoprotein in the peripheral blood of mice increased, and that of high-density lipoprotein decreased. Intestinal fatty acid metabolism-related gene Apolipoprotein E (ApoE), fatty acid synthase (FAS), intestinal fatty acid-binding protein (I-FAPB), acetyl-CoA carboxylase 1 (ACC1), peroxisome proliferator-activated receptor γ (PPARγ), and stearoyl-CoA desaturase 1 (SCD1) increased significantly. Bacteroides, Bifidobacteria, and Lactobacillus counts in feces decreased considerably, while Enterobacter cloacae increased. The activity of isocitrate lyase in feces increased markedly. Treatment of mice with saturated hydrogen led to decreased total cholesterol, total glyceride, and low-density lipoprotein and increased high-density lipoprotein in the peripheral blood. FAS and I-FAPB gene expression in the small intestine decreased. Bacteroides, Bifidobacteria, and Lactobacillus in feces increased significantly, whereas Enterobacter cloacae decreased. The activity of isocitrate lyase also diminished remarkably. These results suggest that saturated hydrogen could improve intestinal structural integrity and lipid metabolism disorders by inhibiting the glyoxylic acid cycle of the intestinal flora. Impact statement Past studies have shown that hydrogen can improve metabolic disorders, but its mechanism of action remains unclear. It is well known that metabolic diseases, such as obesity, are significantly associated with changes in the intestinal flora. The glyoxylic acid cycle is an essential metabolic pathway in prokaryotes, lower eukaryotes, and plants and could be the portal for mechanisms related to metabolic disorders. Many opportunistic pathogenic bacteria can recycle fatty acids to synthesize sugars and other pathogenic substances using the glyoxylic acid cycle. So, the glyoxylic acid cycle may be involved in intestinal dysbacteriosis under high-fat diet. This study, therefore, seeks to provide the mechanism of how hydrogen improves metabolic diseases and a new basis for the use of hydrogen in the treatment of metabolic disorders.

THE METABOLISM OF PUTRESCINE (1,4-DIAMINOBUTANE) BY MYCOBACTERIA ISOLATED FROM FISH: II. STUDIES WITH ARSENITE-INHIBITED CELLS AND CELL-FREE EXTRACTS

1967 ◽  
Vol 13 (5) ◽  
pp. 521-531 ◽  
Author(s):  
T. P. T. Evelyn
Keyword(s):  
Succinic Acid ◽  
Tricarboxylic Acid Cycle ◽  
Significant Proportion ◽  
Tricarboxylic Acid ◽  
The Other ◽  
Aminobutyric Acid ◽  
Succinic Semialdehyde ◽  
Amino Group ◽  
Intact Cells ◽  
Acid Cycle

Three mycobacterial strains isolated from fish degraded putrescine by a pathway in which γ-aminobutyraldehyde (Δ′-pyrroline), γ-aminobutyric acid, succinic semialdehyde, and succinic acid were intermediates. These results agree substantially with those of other workers using different microorganisms. Intact cells utilized γ-aminobutyric acid in a transaminase reaction with endogenously supplied α-ketoglutarate to produce succinic semialdehyde and glutamate. Studies with arsenite-poisoned cells showed that a significant proportion of putrescine was metabolized via pyruvate and alanine. When putrescine-1,4-14C was substrate, HCl extracts of cells contained radioactive aspartate and glutamate in addition to alanine. The further metabolism of succinate therefore proceeded in two directions: one yielding oxalacetate and α-ketoglutarate by way of the tricarboxylic acid cycle, and the other branching off the cycle to yield pyruvate. Studies with cell-free extracts suggested that putrescine nitrogen was assimilated via glutamate, which served as the amino-group donor to yield alanine and aspartate.

The effects of varying the nitrogen, sulphur, and phosphorus content of organic matter on its decomposition

1960 ◽  
Vol 11 (3) ◽  
pp. 317 ◽  
Author(s):  
NJ Barrow
Keyword(s):  
Carbon Dioxide ◽  
Organic Matter ◽  
Organic Compounds ◽  
Phosphorus Content ◽  
Nitrogen Supply ◽  
The Other ◽  
Organic Mixture ◽  
Carbon Nitrogen Ratio ◽  
Phosphorus Mineralization ◽  
Nitrogen Ratio

The decomposition of a mixture of organic compounds was studied by measuring the evolution of carbon dioxide, and changes in the concentration of ammonium, sulphate, and phosphate. In one experiment the nitrogen supply was varied by varying the proportion of glycine in the mixture of organic compounds; in another the sulphur supply was varied by varying the proportion of cysteine; and in a third the phosphorus supply was varied by varying the proportion of sodium ß-glycerophosphate. Mineralization of an element depended on the concentration of that element in the organic mixture. Mineralization of nitrogen did not occur until respiration had lowered the carbon/nitrogen ratio to about 5 and mineralization of sulphur did not occur until respiration had lowered the carbon/sulphur ratio to about 50. On the other hand mineralization of phosphorus occurred before the carbon/phosphorus ratio had been reduced to any consistent figure. This may not be a characteristic of phosphorus mineralization but may have been caused by suboptimal supply of nitrogen. Mineralization of an element also depended on the concentration of other elements and, in general, reduced supplies of one element caused increased mineralization of others.

scholarly journals Minerality in Wine: Towards the Reality behind the Myths

Beverages ◽  
2018 ◽  
Vol 4 (4) ◽  
pp. 77 ◽  
Author(s):  
Wendy Parr ◽  
Alex Maltman ◽  
Sally Easton ◽  
Jordi Ballester
Keyword(s):  
Organic Compounds ◽  
Redox Status ◽  
Mineral Nutrients ◽  
The Other ◽  
Present Review ◽  
Nutrient Elements ◽  
Physico Chemical ◽  
Marked Variability ◽  
Wine Composition ◽  
Wine Fermentations

Tasting minerality in wine is highly fashionable, but it is unclear what this involves. The present review outlines published work concerning how minerality in wine is perceived and conceptualised by wine professionals and consumers. Studies investigating physico-chemical sources of perceived minerality in wine are reviewed also. Unusually, for a wine sensory descriptor, the term frequently is taken to imply a genesis: the sensation is the taste of minerals in the wine that were transported through the vine from the vineyard rocks and soils. Recent studies exploring tasters’ definitions of minerality in wine support this notion. However, there are reasons why this cannot be. First, minerals in wine are nutrient elements that are related distantly only to vineyard geological minerals. Second, mineral nutrients in wine normally have minuscule concentrations and generally lack flavour. Results of reviewed studies overall demonstrate marked variability in both wine professionals’ and wine consumers’ definitions and sensory-based judgments of minerality in wine, although there is some consensus in terms of the other wine attributes that associate with the term mineral. The main wine composition predictors of perceived minerality involve a complex combination of organic compounds dependent on grape ripeness and/or derived from wine fermentations and redox status.

Nitrification as a source of soluble organic substrate in biological treatment

1994 ◽  
Vol 30 (6) ◽  
pp. 1-8 ◽  
Author(s):  
Bruce E. Rittmann ◽  
John M. Regan ◽  
David A. Stahl
Keyword(s):  
Kinetic Analysis ◽  
Organic Compounds ◽  
Biological Treatment ◽  
Heterotrophic Bacteria ◽  
Theoretical Work ◽  
Organic Substrate ◽  
Nitrifying Bacteria ◽  
Organic Substrates ◽  
Soluble Microbial Products ◽  
Microbial Products

In complex, multispecies populations, exchange of substrates can be an important beneficial interaction. Prior experimental and theoretical work has led to the hypothesis that the formation of soluble microbial products (SMP) by nitrifying bacteria can provide a supplementary organic substrate for heterotrophic bacteria, thereby augmenting their accumulation and stability, especially when inputs of organic substrates are low. In this study, chemostat experiments carried out with a NO2−-oxidizing strain (Nitrobacter sp.) and an NH4+-oxidizing strain (Nitrosomonas europaea) demonstrated that both nitrifiers produce SMP that can support heterotrophic bacteria. The first evidence was the presence of significant concentrations of soluble COD in the chemostat effluent, even though the influent was free of organic compounds. Second, a small heterotrophic population was maintained, apparently through utilization of the nitrifier-produced SMP. A preliminary kinetic analysis suggested that SMP kinetic parameters can be adapted from parameters measured for heterotrophs.

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