EVALUATION OF THE ENERGY GAINED BY PSEUDOMONAS AERUGINOSA DURING THE OXIDATION OF GLUCOSE TO 2-KETOGLUCONATE

1956 ◽  
Vol 2 (3) ◽  
pp. 304-309 ◽  
Author(s):  
J. J. R. Campbell ◽  
T. Ramakrishnan ◽  
A. G. Linnes ◽  
B. A. Eagles
Keyword(s):  
Pseudomonas Aeruginosa ◽  
High Energy ◽  
High Energy Phosphate ◽  
Cell Extracts ◽  
Gain Energy ◽  
Oxidation Of Glucose ◽  
Theoretical Amount

Cell extracts of Pseudomonas aeruginosa were shown to oxidize glucose with the accumulation of 2-ketogluconate. The theoretical amount of oxygen was taken up during the reaction and no added hydrogen acceptors were necessary. With glucose as substrate these extracts did not form high energy phosphate nor did they reduce diphosphopyridine nucleotide or triphosphopyridine nucleotide. Almost identical amounts of growth were obtained when limiting equimolar amounts of glucose, gluconate, or 2-ketogluconate were compared as sole sources of carbon. It was concluded that P. aeruginosa 9027 does not gain energy during the oxidative steps glucose –→ gluconate –→ 2-ketogluconate.

PHOSPHORYLATION COUPLED TO THE OXIDATION OF SULFITE AND 2-MERCAPTOETHANOL IN EXTRACTS OF THIOBACILLUS THIOPARUS

1967 ◽  
Vol 13 (7) ◽  
pp. 873-884 ◽  
Author(s):  
E. A. Davis ◽  
E. J. Johnson
Keyword(s):  
Electron Donor ◽  
Adenosine Monophosphate ◽  
Adenosine Diphosphate ◽  
High Energy ◽  
High Energy Phosphate ◽  
Thiobacillus Thioparus ◽  
Ph Values ◽  
Cell Extracts ◽  
Endogenous Level ◽  
Sulfite Oxidation

The effect of 10−4 M 2, 4-dinitrophenol (DNP) on the production of high energy phosphate bonds during sulfite and 2-mercaptoethanol (2-ME) oxidation by cell extracts of Thiobacillus thioparus was determined. Phosphorylation was measured indirectly by14CO2fixation and directly by32PO4esterification. DNP-sensitive phosphorylation was demonstrated by coupling sulfite oxidation with the concomitant phosphorylation of adenosine monophosphate (AMP) to14CO2fixation beginning with ribose-5-phosphate. Esterification of32PO4was measured at pH values of 6.4, 7.2, and 8.0 with AMP and adenosine diphosphate (ADP) as the phosphate acceptor and sulfite as the electron donor. The optimal pH for the greatest DNP-sensitive phosphorylation was 7.2 with AMP. DNP at 10−4 M significantly reduced32PO4esterification at all pH values tested and with the three ADP concentrations employed. Maximum DNP-sensitive phosphorylation of ADP was demonstrated with 5 μmoles of ADP at pH 7.2. The maximum P:O ratio was 0.13. With 2-ME as the nonphysiological electron donor and AMP as the phosphate acceptor, no phosphorylation above the endogenous level was measured at the three pH values tested. With ADP as the phosphate acceptor and 2-ME as the electron donor,32PO4esterification significantly above the endogenous level was demonstrated at pH 6.4 with 5 μmoles of ADP; this phosphorylation was sensitive to 10−4 M DNP.

THE ACCUMULATION OF α-KETOGLUTARATE BY SUSPENSIONS OF PSEUDOMONAS AERUGINOSA

1966 ◽  
Vol 12 (5) ◽  
pp. 1005-1013 ◽  
Author(s):  
Margaret von Tigerstrom ◽  
J. J. R. Campbell
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Glucose Oxidation ◽  
Ammonium Salts ◽  
Acid Oxidation ◽  
Glucose Medium ◽  
Cell Extracts ◽  
Metabolic Pool ◽  
Low Levels ◽  
The Individual ◽  
Oxidation Of Glucose

Pyruvic and α-ketoglutaric acids accumulated during the oxidation of glucose by washed cell suspensions of Pseudomonas aeruginosa harvested from a glucose medium. The addition of ammonium salts had been shown to prevent the accumulation of the α-ketoglutaric acid in such suspensions. A similar situation was shown to exist with growing cultures. The accumulation of α-ketoglutaric acid was not due to inability of the cells to synthesize enzymes required for the oxidation of this compound. Cells harvested from a glucose medium required an induction period before oxidizing α-ketoglutaric acid but this was apparently due to the lack of a permease required for the transport of the substrate across the cell membrane. A comparison of the enzyme levels of cell extracts prepared from cells grown on a glucose medium with those grown on an α-ketoglutaric acid medium revealed that the latter had a higher level of the individual apoenzymes required for α-ketoglutaric acid oxidation. However, the apoenzyme level of the extracts of glucose-grown cells appeared adequate to prevent the accumulation of α-ketoglutaric acid during glucose oxidation.It is concluded that during growth in the presence of an excess of ammonium salts α-ketoglutarate never escapes from the internal metabolic pool of the cells and therefore the permease for α-ketoglutarate is not synthesized. During glucose oxidation by washed suspensions of glucose-grown cells, α-ketoglutarate is perhaps excreted from the cell either because the cells are deficient in the coenzymes necessary for α-ketoglutarate oxidation or because the avidity of the enzymes for substrate is such that, at low levels of substrate, the enzymes of α-ketoglutarate oxidation act so slowly that the intermediate accumulates.

scholarly journals Energy Metabolism of Human Leukemic Lymphocytes and Granulocytes

Blood ◽  
1967 ◽  
Vol 30 (2) ◽  
pp. 151-167 ◽  
Author(s):  
JOHN LASZLO ◽  
Clarence Ellis
Keyword(s):  
Energy Metabolism ◽  
Chronic Lymphocytic Leukemia ◽  
Glucose Concentration ◽  
Acute Lymphocytic Leukemia ◽  
Aerobic Glycolysis ◽  
High Energy ◽  
Lymphocytic Leukemia ◽  
Anaerobic Conditions ◽  
High Energy Phosphate

Abstract 1. Leukocytes taken from patients having acute lymphocytic leukemia and chronic lymphocytic leukemia are characterized by high respiratory rates and low to absent aerobic glycolysis. Leukemic granulocytes have low respiratory rates and high aerobic glycolysis. 2. Lymphocytes and granulocytes have the capacity for high glycolytic rates under anaerobic conditions. 3. Lymphocyte respiration is independent of glucose concentration in contrast to granulocyte respiration. 4. High energy phosphate levels of lymphocytes and granulocytes are unchanged if these cells are incubated aerobically, either with or without glucose, or anaerobically in the presence of glucose. 5. Aerobic glycolysis can be induced in lymphocytes by the addition of foreign plasma. Foreign plasma may also alter granulocyte metabolism.

Responses of beta-adrenoceptor in rat soleus to phosphorus compound levels and/or unloading

1994 ◽  
Vol 266 (5) ◽  
pp. C1257-C1262 ◽  
Author(s):  
Y. Ohira ◽  
K. Saito ◽  
T. Wakatsuki ◽  
W. Yasui ◽  
T. Suetsugu ◽  
...  
Keyword(s):  
Contractile Activity ◽  
Creatine Supplementation ◽  
High Energy ◽  
Hindlimb Suspension ◽  
Phosphorus Compounds ◽  
High Energy Phosphates ◽  
High Energy Phosphate ◽  
Gravitational Unloading ◽  
Beta Adrenoceptor ◽  
Muscle Contractile

Responses of beta-adrenoceptor (beta-AR) in rat soleus to gravitational unloading and/or changes in the levels of phosphorus compounds by feeding either creatine or its analogue beta-guanidinopropionic acid (beta-GPA) were studied. A decrease in the density of beta-AR (about -35%) was induced by 10 days of hindlimb suspension, but the affinity of the receptor was unaffected. Suspension unloading tended to increase the levels of adenosine triphosphate and phosphocreatine and decrease inorganic phosphate. Even without unloading, the beta-AR density decreased after an oral creatine supplementation (about -20%), which also tended to elevate the high-energy phosphate levels in muscle. However, an elevation of beta-AR density was induced (about +36%) after chronic depletion of high-energy phosphates by feeding beta-GPA (about +125%). Data suggest that the density of beta-AR in muscle is elevated if the high-energy phosphate contents are chronically decreased and vice versa. However, it may not be directly related to the degree of muscle contractile activity.

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