ATP regeneration using immobilized carbamyl phosphokinase

1973 ◽  
Vol 15 (3) ◽  
pp. 447-453 ◽  
Author(s):  
David L. Marshall
Keyword(s):  
Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 31
Author(s):  
Samuel E. Weinberg ◽  
Le Yu Sun ◽  
Allison L. Yang ◽  
Jie Liao ◽  
Guang Yu Yang

Chronic inflammation is one of the most common and well-recognized risk factors for human cancer, including colon cancer. Inflammatory bowel disease (IBD) is defined as a longstanding idiopathic chronic active inflammatory process in the colon, including ulcerative colitis and Crohn’s disease. Importantly, patients with IBD have a significantly increased risk for the development of colorectal carcinoma. Dietary inositol and its phosphates, as well as phospholipid derivatives, are well known to benefit human health in diverse pathologies including cancer prevention. Inositol phosphates including InsP3, InsP6, and other pyrophosphates, play important roles in cellular metabolic and signal transduction pathways involved in the control of cell proliferation, differentiation, RNA export, DNA repair, energy transduction, ATP regeneration, and numerous others. In the review, we highlight the biologic function and health effects of inositol and its phosphates including the nature and sources of these molecules, potential nutritional deficiencies, their biologic metabolism and function, and finally, their role in the prevention of colitis-induced carcinogenesis.


2000 ◽  
Vol 64 (10) ◽  
pp. 2259-2261 ◽  
Author(s):  
Hisashi KAWASAKI ◽  
Yoshihiro USUDA ◽  
Megumi SHIMAOKA ◽  
Takashi UTAGAWA
Keyword(s):  

1994 ◽  
Vol 267 (2) ◽  
pp. C357-C366 ◽  
Author(s):  
P. Korge ◽  
K. B. Campbell

Ca2+ pump function of skeletal muscle sarcoplasmic reticulum (SR) vesicles was measured by monitoring Ca2+ uptake and efflux with a Ca(2+)-sensitive minielectrode and adenosinetriphosphatase (ATPase) activity of the same preparation under the same conditions. The efficiency of Ca2+ transport into SR vesicles, defined by the amount of Ca2+ transported per ATP hydrolyzed (coupling ratio), varied significantly depending on assay conditions. Coupling ratio increased in parallel with increase in precipitating anion concentration, which is supposed to decrease accumulation of free Ca2+ inside vesicles and its subsequent efflux. Membrane-bound creatine kinase-creatine phosphate (CK-CP) system, acting as a ADP sensor and local ATP regenerator, significantly improved Ca2+ pump function when the pump worked with low efficiency (coupling ratio < 1). The effect of CK-CP system on Ca2+ pump function was also dependent on extravesicular Ca2+ concentration ([Ca2+]o), the effect being most significant at high initial [Ca2+]o. Under conditions in which SR vesicles were allowed to decrease [Ca2+]o, as occurs also during muscle relaxation, plateau values of Ca(2+)-ATPase activity were reached at significantly higher [Ca2+]o (54 +/- 5.7, n = 6), compared with leaky vesicles or the condition in which [Ca2+]o was maintained. By preventing local accumulation of ADP, generated in ATPase reactions, CK-CP system also inhibited Ca2+ efflux under conditions in which this efflux was stimulated by the increase of free Ca2+ inside vesicles. This effect was at least partially responsible for the CK-CP-supported increase in Ca2+ uptake and coupling ratios that were more expressed at low precipitating anion concentration. We hypothesize that local ATP regeneration by CK-CP system is one mechanism the cell can use to improve Ca2+ uptake by SR in emergency conditions, where excessive increase in cytoplasmic [Ca2+] may have deleterious effects.


2020 ◽  
Vol 486 ◽  
pp. 110870 ◽  
Author(s):  
Caixia Cui ◽  
Hong Ming ◽  
Linjing Li ◽  
Mingjie Li ◽  
Jian Gao ◽  
...  

1986 ◽  
Vol 18 (11) ◽  
pp. 985-990 ◽  
Author(s):  
Adrie J.M. Verhoeven ◽  
Marlene E. Mommersteeg ◽  
Jan-Willem N. Akkerman

ChemBioChem ◽  
2020 ◽  
Vol 21 (15) ◽  
pp. 2088-2088
Author(s):  
Christin Kleineberg ◽  
Christian Wölfer ◽  
Amirhossein Abbasnia ◽  
Dennis Pischel ◽  
Claudia Bednarz ◽  
...  
Keyword(s):  

ChemBioChem ◽  
2020 ◽  
Vol 21 (15) ◽  
pp. 2149-2160 ◽  
Author(s):  
Christin Kleineberg ◽  
Christian Wölfer ◽  
Amirhossein Abbasnia ◽  
Dennis Pischel ◽  
Claudia Bednarz ◽  
...  
Keyword(s):  

1981 ◽  
Author(s):  
W van Brederode ◽  
G Gorter ◽  
J W N Akkerman

WAS is a severe, X-linked disorder, characterized by eczema, immunodeficiency and an increased bleeding tendency caused by thrombocytopenia and platelet malfunction. There is a diminished epinephrine-induced aggregation response and an abnormal mitochondrial CO2 production during platelet activation. From this, Shapiro et al (The Lancet 1978) concluded that WAS-platelets have a defect in mitochondrial ATP regeneration, which could be employed for detection of WAS- carriers, who are clinically normal and have only minor platelet defects. The test consists of an epinephrine-induced aggregation in the presence of an inhibitor of glycolytic ATP production (deoxyglucose, 2 DG), and showed impaired second wave aggregation in obligate carriers but not in normal controls. We tested 4 unrelated obligate WAS-carriers and found impaired aggregations in all. Five out of 7 female relatives also showed aggregation abnormalities, suggestive for WAS-carriership. However, in 8 out of 15 normal controls (males and females) the test was also positive. The nature of a possible defect in mitochondrial ATP supply was further studied in gel-filtered platelets by analyzing the metabolic ATP level before and during epinephrine-induced aggregation in the presence of inhibitors of glycolysis and glycogenoly- sis and during incubation in substrate-depleted medium. These studies showed that mitochondrial energy generation depended on sugar supply either from glycolysis or glycoge- nolysis and was unable to maintain a normal metabolic ATP level when these pathways were inhibited. Incubation with 2DG led to a fall in metabolic ATP and - consequently - to an impaired epinephrine-induced aggregation. The fall of metabolic ATP (2DG present) was much steeper in platelets from 2 unrelated WAS-patients than in cells from normal controls; most (but not all) obligate carriers showed intermediate values. It is concluded that the impaired epinephrine-induced aggregation in the presence of 2DG in WAS reflects disturbances in ATP homeostasis, which are consistent with a mitochondrial defect.


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