Novel Energy Metabolism in Anaerobic Hyperthermophilic Archaea: A Modified Embden-Meyerhof Pathway.

2002 ◽  
Vol 93 (5) ◽  
pp. 441-448 ◽  
Author(s):  
HARUHIKO SAKURABA ◽  
TOSHIHISA OHSHIMA
Keyword(s):  
Energy Metabolism ◽  
Hyperthermophilic Archaea ◽  
Modified Embden Meyerhof Pathway

scholarly journals ADP-Dependent Phosphofructokinases in Mesophilic and Thermophilic Methanogenic Archaea

2001 ◽  
Vol 183 (24) ◽  
pp. 7145-7153 ◽  
Author(s):  
Corné H. Verhees ◽  
Judith E. Tuininga ◽  
Servé W. M. Kengen ◽  
Alfons J. M. Stams ◽  
John van der Oost ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Phylogenetic Analysis ◽  
Methanogenic Archaea ◽  
Hyperthermophilic Archaea ◽  
Acetyl Phosphate ◽  
Gene Encoding ◽  
Substrate Specificities ◽  
Key Enzyme ◽  
Domains Of Life ◽  
Modified Embden Meyerhof Pathway

ABSTRACT Phosphofructokinase (PFK) is a key enzyme of the glycolytic pathway in all domains of life. Two related PFKs, ATP-dependent and PPi-dependent PFK, have been distinguished in bacteria and eucarya, as well as in some archaea. Hyperthermophilic archaea of the order Thermococcales, including Pyrococcus andThermococcus spp., have recently been demonstrated to possess a unique ADP-dependent PFK (ADP-PFK) that appears to be phylogenetically distinct. Here, we report the presence of ADP-PFKs in glycogen-producing members of the orders Methanococcalesand Methanosarcinales, including both mesophilic and thermophilic representatives. To verify the substrate specificities of the methanogenic kinases, the gene encoding the ADP-PFK fromMethanococcus jannaschii was functionally expressed inEscherichia coli, and the produced enzyme was purified and characterized in detail. Compared to its counterparts from the two members of the order Thermococcales, the M. jannaschii ADP-PFK has an extremely lowKm for fructose 6-phosphate (9.6 μM), and it accepts both ADP and acetyl-phosphate as phosphoryl donors. Phylogenetic analysis of the ADP-PFK reveals it to be a key enzyme of the modified Embden-Meyerhof pathway of heterotrophic and chemolithoautotrophic archaea. Interestingly, uncharacterized homologs of this unusual kinase are present in several eucarya.

Mitochondrial matrix calcium ions regulate energy production in myocardium: A cytochemical study

1990 ◽  
Vol 48 (2) ◽  
pp. 166-167
Author(s):  
W.A. Jacob ◽  
R. Hertsens ◽  
A. Van Bogaert ◽  
M. De Smet
Keyword(s):  
Energy Metabolism ◽  
Calcium Ions ◽  
Energy Production ◽  
Regulation Of Respiration ◽  
Free Calcium ◽  
Mitochondrial Matrix ◽  
Cytochemical Study ◽  
Nmr Techniques

In the past most studies of the control of energy metabolism focus on the role of the phosphorylation potential ATP/ADP.Pi on the regulation of respiration. Studies using NMR techniques have demonstrated that the concentrations of these compounds for oxidation phosphorylation do not change appreciably throughout the cardiac cycle and during increases in cardiac work. Hence regulation of energy production by calcium ions, present in the mitochondrial matrix, has been the object of a number of recent studies.Three exclusively intramitochondnal dehydrogenases are key enzymes for the regulation of oxidative metabolism. They are activated by calcium ions in the low micromolar range. Since, however, earlier estimates of the intramitochondnal calcium, based on equilibrium thermodynamic considerations, were in the millimolar range, a physiological correlation was not evident. The introduction of calcium-sensitive probes fura-2 and indo-1 made monitoring of free calcium during changing energy metabolism possible. These studies were performed on isolated mitochondria and extrapolation to the in vivo situation is more or less speculative.

Soy isoflavone Genistein affects energy metabolism in a steatotic liver model

2012 ◽  
Vol 50 (01) ◽  
Author(s):  
S Lünse ◽  
A Krüger ◽  
M Glanemann ◽  
G Damm
Keyword(s):  
Energy Metabolism ◽  
Soy Isoflavone ◽  
Steatotic Liver ◽  
Liver Model

Regulation of energy metabolism in hepatocytes with induced steatosis

2015 ◽  
Vol 53 (01) ◽  
Author(s):  
K Schönefeld ◽  
M Matz-Soja ◽  
J Böttger ◽  
P Seibel ◽  
R Gebhardt
Keyword(s):  
Energy Metabolism

Dysregulation of energy metabolism in obesity and its implications for cancer

2016 ◽  
Vol 02 (03) ◽  
pp. 133-142
Author(s):  
Andrew Hoffman ◽  
Lauren Battaglia ◽  
Michael DeStefano ◽  
Emine Abali
Keyword(s):  
Energy Metabolism
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