scholarly journals STUDIES ON THE METABOLISM OF AUTOTROPHIC BACTERIA

1942 ◽  
Vol 26 (1) ◽  
pp. 103-117 ◽  
Author(s):  
K. G. Vogler
Keyword(s):  
Co2 Fixation ◽  
Physiological Condition ◽  
Sulfur Oxidation ◽  
Considerable Importance ◽  
Resting Cells ◽  
Oxidizing Agent ◽  
Anaerobic Conditions ◽  
Thiobacillus Thiooxidans ◽  
Autotrophic Bacteria ◽  
Growth Bound

In a study of chemosynthesis (the fixation of CO2 by autotrophic bacteria in the dark) in Thiobacillus thiooxidans, the data obtained support the following conclusions: 1. CO2 can be fixed by "resting cells" of Thiobacillus thiooxidans; the fixation is not "growth bound." 2. The physiological condition of the cell is of considerable importance in determining CO2 fixation. 3. CO2 fixation can occur in the absence of oxidizable sulfur in "young" cells. The extent of this fixation appears to be dependent upon the pCO2. 4. CO2 fixation can also occur under anaerobic conditions and the presence of sulfur does not influence such fixation. 5. However, in the CO2 fixation by cells in the absence of sulfur, only a limited amount of CO2 can be fixed. This amount is approximately 40 µl. CO2 per 100 micrograms bacterial nitrogen. After a culture has utilized this amount of CO2 it no longer has the ability to fix CO2 but releases it during its respiration. 6. Relatively short periods of sulfur oxidation can restore the ability of cells to fix CO2 under conditions where sulfur oxidation is prevented. 7. It is possible to oxidize sulfur in the absence of CO2 and to store the energy thus formed within the cell. It is then possible to use this energy at a later time for the fixation of CO2 in the entire absence of sulfur oxidation. 8. Cultures of Thiobacillus thiooxidans respiring on sulfur utilize CO2 in a reaction which proceeds to a zero concentration of CO2 in the atmosphere. 9. CO2 may act as an oxidizing agent for sulfur. 10. Hydrogen is not utilized by the organism. 11. It is possible to selectively inhibit sulfur oxidation and CO2 fixation.

scholarly journals STUDIES ON THE METABOLISM OF AUTOTROPHIC BACTERIA

1942 ◽  
Vol 26 (1) ◽  
pp. 89-102 ◽  
Author(s):  
K. G. Vogler ◽  
G. A. LePage ◽  
W. W. Umbreit
Keyword(s):  
Sulfuric Acid ◽  
Organic Acids ◽  
Bacterial Cell ◽  
Sulfur Oxidation ◽  
Energy Of Activation ◽  
Detectable Effect ◽  
Intact Cells ◽  
Thiobacillus Thiooxidans ◽  
Autotrophic Bacteria ◽  
Autotrophic Bacterium

The data of this paper indicate that: 1. The "energy of activation" (µ) of sulfur oxidation by the autotrophic bacterium, Thiobacillus thiooxidans, is similar to that of other respirations. 2. The pH of the menstruum does not influence the respiration on sulfur between the limits of pH 2 to 4.8 once contact between the bacterial cell and the sulfur particle has been established but it does influence the rate at which such contact occurs. 3. The pO2 has little effect upon the respiration of this organism. 4. Most organic materials have no detectable effect upon the respiration of Thiobacillus thiooxidans, but the organic acids of terminal respiration seem to stimulate the respiration in the absence of oxidizable sulfur and certain of them inhibit sulfur oxidation. 5. In so far as inhibitor studies on intact cells are trustworthy, sulfur oxidation goes through iron-containing systems similar to cytochrome. It is possible that the oxygen contained in the sulfuric acid formed during sulfur oxidation is derived from the oxygen of the water.

scholarly journals STUDIES ON THE METABOLISM OF THE AUTOTROPHIC BACTERIA

1942 ◽  
Vol 26 (2) ◽  
pp. 157-168 ◽  
Author(s):  
K. G. Vogler ◽  
W. W. Umbreit
Keyword(s):  
Bond Energy ◽  
Inorganic Phosphate ◽  
Energy Input ◽  
Co2 Fixation ◽  
Sulfur Oxidation ◽  
Energy Utilization ◽  
Phosphate Release ◽  
Autotrophic Bacteria ◽  
Constant Rate ◽  
Autotrophic Bacterium

In the autotrophic bacterium, Thiobacillus thiooxidans, the oxidation of sulfur is coupled to transfers of phosphate from the medium to the cells. CO2 fixation is coupled to transfers of inorganic phosphate from the cells to the medium and is dependent, in the absence of concomitant sulfur oxidation, upon the amount of phosphate previously taken up during sulfur oxidation. The energy reservoir, which is formed by sulfur oxidation in the absence of CO2 and which can be released for the fixation of CO2 under conditions which do not permit sulfur oxidation, is a phosphorylated compound and the data suggest that the energy is stored in the cell as phosphate bond energy. It is possible to oxidize sulfur at a constant rate for hours in the absence of CO2. The phosphate energy formed during this process is probably released by cell phosphotases. It is possible to inhibit these phosphotases by means of inorganic phosphate and thus to inhibit sulfur oxidation in the absence of CO2. In the presence of CO2, where alternative uses for the phosphate energy are available, the inhibition is relieved. Sulfur oxidation (energy input) is coupled, not to CO2 fixation, but to phosphate esterification. CO2 fixation (energy utilization) is coupled with phosphate release.

scholarly journals THE PRESENCE OF AN ENDOGENOUS RESPIRATION IN THE AUTOTROPHIC BACTERIA

1942 ◽  
Vol 25 (4) ◽  
pp. 617-622 ◽  
Author(s):  
K. G. Vogler
Keyword(s):  
Oxygen Uptake ◽  
Organic Materials ◽  
Endogenous Respiration ◽  
Thiobacillus Thiooxidans ◽  
Autotrophic Bacteria ◽  
Autotrophic Bacterium

It is shown that there exists in the autotrophic bacterium Thiobacillus thiooxidans a measurable oxygen uptake in the absence of the specific nutrient (sulfur). This respiration is shown to be due to the utilization of organic materials which must have been previously synthesized by the chemosynthetic process, providing evidence that autotrophic bacteria contain a dissimilatory process which involves the breakdown of organic materials and furnishes energy for the maintenance of the cell during periods in which the specific nutrient is absent. This is entirely in accord with the work of Bömeke (1939), who provided similar types of proof for Nitrosomonas and Nitrobacter. One may conclude, therefore, that autotrophic bacteria possess an endogenous respiration which involves the utilization of previously synthesized organic materials.

scholarly journals Biotransformation of 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-Hexaazaisowurtzitane (CL-20) by Denitrifying Pseudomonas sp. Strain FA1

2003 ◽  
Vol 69 (9) ◽  
pp. 5216-5221 ◽  
Author(s):  
Bharat Bhushan ◽  
Louise Paquet ◽  
Jim C. Spain ◽  
Jalal Hawari
Keyword(s):  
Nitrous Oxide ◽  
Enzyme Preparation ◽  
Electron Transfer Reaction ◽  
Garden Soil ◽  
Resting Cells ◽  
Anaerobic Conditions ◽  
Intact Cells ◽  
Cell Biomass ◽  
Membrane Enzyme ◽  
Enzyme Catalyzed Reactions

ABSTRACT The microbial and enzymatic degradation of a new energetic compound, 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20), is not well understood. Fundamental knowledge about the mechanism of microbial degradation of CL-20 is essential to allow the prediction of its fate in the environment. In the present study, a CL-20-degrading denitrifying strain capable of utilizing CL-20 as the sole nitrogen source, Pseudomonas sp. strain FA1, was isolated from a garden soil. Studies with intact cells showed that aerobic conditions were required for bacterial growth and that anaerobic conditions enhanced CL-20 biotransformation. An enzyme(s) involved in the initial biotransformation of CL-20 was shown to be membrane associated and NADH dependent, and its expression was up-regulated about 2.2-fold in CL-20-induced cells. The rates of CL-20 biotransformation by the resting cells and the membrane-enzyme preparation were 3.2 ± 0.1 nmol h−1 mg of cell biomass−1 and 11.5 ± 0.4 nmol h−1 mg of protein−1, respectively, under anaerobic conditions. In the membrane-enzyme-catalyzed reactions, 2.3 nitrite ions (NO2 −), 1.5 molecules of nitrous oxide (N2O), and 1.7 molecules of formic acid (HCOOH) were produced per reacted CL-20 molecule. The membrane-enzyme preparation reduced nitrite to nitrous oxide under anaerobic conditions. A comparative study of native enzymes, deflavoenzymes, and a reconstituted enzyme(s) and their subsequent inhibition by diphenyliodonium revealed that biotransformation of CL-20 is catalyzed by a membrane-associated flavoenzyme. The latter catalyzed an oxygen-sensitive one-electron transfer reaction that caused initial N denitration of CL-20.

Absence of glucokinase in Methanomonas sp. as a cause for their inability to grow on glucose

1972 ◽  
Vol 18 (12) ◽  
pp. 1907-1913 ◽  
Author(s):  
Kei Amemiya
Keyword(s):  
Phosphate Esters ◽  
Resting Cells ◽  
Obligate Methylotroph ◽  
Enzymatic Assays ◽  
Autotrophic Bacteria ◽  
Toxic Product ◽  
A Cell ◽  
Flow Through ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Autotrophic Bacterium

Many obligate autotrophic bacteria can be grown on glucose using a dialysis flow-through system. Methanomonas methanooxidans, an obligate methylotroph, exhibits many of the properties of an obligate autotrophic bacterium but we have been unable to grow it on glucose using dialysis. In the obligate autotrophic bacteria, the dialysis procedure seems to be removing a toxic product of glucose metabolism but this does not seem to be the case with the methylotroph. Enzymatic assays on a cell-free extract from methane-grown or methane plus glucose-grown cells showed only phosphoglucoisomerase activity, while glucokinase and glucose-6-phosphate dehydrogenase activity were not detected. Studies with resting cells showed that glucose was not oxidized, although the phosphate esters of glucose, fructose, ribose, and gluconate were oxidized. CO2 fixation occurred only in the presence of glucose-6-phosphate. The rate of oxygen consumed and CO2 fixed on glucose-6-phosphate were almost identical with that when methanol was used as the substrate. When the phosphate esters of glucose, fructose, and ribose were used as the sole energy source, only glucose-6-phosphate supported growth to any extent; in fact, the amount of growth was essentially the same as that obtained with methanol. The results from this study suggest that the inability of this organism to grow on glucose may be due to the absence of adequate glucokinase.

scholarly journals Kinetic Constant Variability in Bacterial Oxidation of Elemental Sulfur

2007 ◽  
Vol 73 (11) ◽  
pp. 3752-3754 ◽  
Author(s):  
Blanka Pokorna ◽  
Martin Mandl ◽  
Sarka Borilova ◽  
Pavla Ceskova ◽  
Romana Markova ◽  
...  
Keyword(s):  
Acidithiobacillus Ferrooxidans ◽  
Elemental Sulfur ◽  
Kinetic Constant ◽  
Sulfur Oxidation ◽  
Growth Yields ◽  
Resting Cells ◽  
Michaelis Constant ◽  
Bacterial Oxidation ◽  
Batch Cultures ◽  
Oxidation Rates

ABSTRACT Wide ranges of growth yields on sulfur (from 2.4 × 1010 to 8.1 × 1011 cells g−1) and maximum sulfur oxidation rates (from 0.068 to 1.30 mmol liter−1 h−1) of an Acidithiobacillus ferrooxidans strain (CCM 4253) were observed in 73 batch cultures. No significant correlation between the constants was observed. Changes of the Michaelis constant for sulfur (from 0.46 to 15.5 mM) in resting cells were also noted.

scholarly journals High-Level Acetaldehyde Production in Lactococcus lactis by Metabolic Engineering

2005 ◽  
Vol 71 (2) ◽  
pp. 1109-1113 ◽  
Author(s):  
Roger S. Bongers ◽  
Marcel H. N. Hoefnagel ◽  
Michiel Kleerebezem
Keyword(s):  
Metabolic Engineering ◽  
Lactococcus Lactis ◽  
Zymomonas Mobilis ◽  
Nadh Oxidase ◽  
Pyruvate Decarboxylase ◽  
Resting Cells ◽  
Anaerobic Conditions ◽  
High Level ◽  
Acetaldehyde Production ◽  
Combined Overexpression

ABSTRACT Efficient conversion of glucose to acetaldehyde is achieved by nisin-controlled overexpression of Zymomonas mobilis pyruvate decarboxylase (pdc) and Lactococcus lactis NADH oxidase (nox) in L. lactis. In resting cells, almost 50% of the glucose consumed could be redirected towards acetaldehyde by combined overexpression of pdc and nox under anaerobic conditions.

Effects of preillumination with light of different wavelengths on subsequent dark CO2-fixation in Chlorella cells

1970 ◽  
Vol 48 (6) ◽  
pp. 1203-1207 ◽  
Author(s):  
Shigetoh Miyachi ◽  
Daisuke Hogetsu
Keyword(s):  
Blue Light ◽  
Co2 Fixation ◽  
Red Light ◽  
Anaerobic Conditions ◽  
Nitrogen Gas ◽  
Pep Carboxylase ◽  
Radioactive Carbon ◽  
Initial Fixation ◽  
Dark Fixation ◽  
Dark Co2 Fixation

The effects of preillumination with monochromatic red or blue light on the subsequent dark 14CO2-fixation in Chlorella cells were studied under aerobic as well as anaerobic conditions. When the cell suspension was made aerobic by bubbling air (CO2-free) throughout the periods of preillumination and the following dark 14CO2-fixation, the initial fixation product was mainly PGA. The radioactive carbon first incorporated in PGA was transferred mostly to aspartate during the later periods of dark 14CO2-fixation. The rate of 14C-incorporation into aspartate after preillumination with blue light was 2 to 3 times as high as that observed after red-light pretreatment. The observations support our previous inference that the activity of PEP carboxylase in Chlorella cells is stimulated by preillumination with blue light. When nitrogen gas was used during preillumination and the subsequent dark fixation, the radioactivity of 14C incorporated during the initial enhanced 14CO2-fixation was eventually transferred to alanine and lactate. The increase in radioactivity of alanine and lactate was more pronounced during dark fixation after preillumination with red light than after preillumination with blue light.

Effect of nutrients and elemental sulfur particle size on elemental sulfur oxidation and the growth of Thiobacillus thiooxidans

1997 ◽  
Vol 48 (4) ◽  
pp. 497 ◽  
Author(s):  
Sholeh ◽  
Rod D. B. Lefroy ◽  
Graeme J. Blair
Keyword(s):  
Particle Size ◽  
Elemental Sulfur ◽  
Sulfur Oxidation ◽  
Thiobacillus Thiooxidans ◽  
Oxidation Rates ◽  
South Wales ◽  
Incubation Experiments ◽  
P Rate ◽  
Oxidation Model ◽  
S Oxidation

Elemental sulfur (S) has many attractions as a fertiliser but it must be oxidised to sulfate before it is plant available. Two laboratory incubation experiments with a high S sorbing basaltic soil (Haplohumult) from Walcha, New South Wales, are reported here. The first experiment was conducted to study the effect of ? P and other nutrients on the oxidation of elemental S and the growth of Thiobacillus thiooxidans. The second experiment studied the effect of phosphorus (P) rate, elemental S particle size, and elemental S form on the oxidation of elemental S at different times. There were significant differences between treatments in the percentage and amount of elemental S oxidised, with the lowest oxidation occurring during the 6-week incubation in the P treatment, which represented 1�8% of the applied S compared with 16�0% when all nutrients were supplied. There was a significant linear relationship between T. thiooxidans population at the end of the incubation period and the amount of elemental S oxidised. The oxidation of elemental S was higher when fine (50?150 �m) particle size elemental S was used, compared with coarse (150?250 �m) elemental S. There was no clear difference in oxidation rate between ground and recrystallised elemental S. The S oxidation rates recorded in these experiments were compared with those predicted by an S oxidation model and found to be in close agreement.

Sign in / Sign up

Export Citation Format

Share Document