scholarly journals Cyclic adenosine monophosphate-dependent kinase in cystic fibrosis tracheal epithelium.

1987 ◽  
Vol 80 (6) ◽  
pp. 1799-1802 ◽  
Author(s):  
R Barthelson ◽  
J Widdicombe
Keyword(s):  
Cystic Fibrosis ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Tracheal Epithelium

scholarly journals Platelet activation in cystic fibrosis

Blood ◽  
2005 ◽  
Vol 105 (12) ◽  
pp. 4635-4641 ◽  
Author(s):  
Brian P. O'Sullivan ◽  
Matthew D. Linden ◽  
Andrew L. Frelinger ◽  
Marc R. Barnard ◽  
Michele Spencer-Manzon ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Platelet Aggregation ◽  
Platelet Activation ◽  
Platelet Reactivity ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Gene Encoding ◽  
Platelet Surface ◽  
Beneficial Effects ◽  
Plasma Factor

Abstract Cystic fibrosis (CF) is caused by a mutation of the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). We examined platelet function in CF patients because lung inflammation is part of this disease and platelets contribute to inflammation. CF patients had increased circulating leukocyte-platelet aggregates and increased platelet responsiveness to agonists compared with healthy controls. CF plasma caused activation of normal and CF platelets; however, activation was greater in CF platelets. Furthermore, washed CF platelets also showed increased reactivity to agonists. CF platelet hyperreactivity was incompletely inhibited by prostaglandin E1 (PGE1). As demonstrated by Western blotting and reverse-transcriptase-polymerase chain reaction (RT-PCR), there was neither CFTR nor CFTR-specific mRNA in normal platelets. There were abnormalities in the fatty acid composition of membrane fractions of CF platelets. In summary, CF patients have an increase in circulating activated platelets and platelet reactivity, as determined by monocyte-platelet aggregation, neutrophil-platelet aggregation, and platelet surface P-selectin. This increased platelet activation in CF is the result of both a plasma factor(s) and an intrinsic platelet mechanism via cyclic adenosine monophosphate (cAMP)/adenylate cyclase, but not via platelet CFTR. Our findings may account, at least in part, for the beneficial effects of ibuprofen in CF. (Blood. 2005;105:4635-4641)

Cystic fibrosis

2011 ◽  
Author(s):  
R. Mark Beattie ◽  
Anil Dhawan ◽  
John W.L. Puntis
Keyword(s):  
Cystic Fibrosis ◽  
Clinical Symptoms ◽  
Gastrointestinal Symptoms ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Transmembrane Conductance Regulator ◽  
Transmembrane Conductance ◽  
Regulator Protein ◽  
Salt And Water Balance ◽  
Cystic Fibrosis Transmembrane

Gastrointestinal manifestations 156Management of gastrointestinal symptoms in children with CF 158Nutrition in CF 158Nutritional management 159Vitamins 160The incidence of cystic fibrosis (CF) is around 1 in 2500. Cases are diagnosed as a consequence of population screening or high-risk screening, or following presentation with clinical symptoms typical of the disorder. The basic defect is in the CFTR (cystic fibrosis transmembrane conductance regulator) protein which codes for a cyclic adenosine monophosphate-regulated chloride transporter in epithelial cells of exocrine organs. This is involved in salt and water balance across epithelial surfaces. The gene is on chromosome 7. There are multiple known mutations, the most common being ...

Mechanisms of ATP to cAMP Conversion Catalyzed by the Mammalian Adenylyl Cyclase: A Role of Magnesium Coordination Shells and Proton Wires

2019 ◽  
Author(s):  
Bella Grigorenko ◽  
Igor Polyakov ◽  
Alexander Nemukhin
Keyword(s):  
Adenylyl Cyclase ◽  
Bond Cleavage ◽  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Md Simulations ◽  
Coordination Shell ◽  
Energy Profile ◽  
One Step ◽  
Type V

<p>We report a mechanism of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP) conversion by the mammalian type V adenylyl cyclase revealed in molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) simulations. We characterize a set of computationally derived enzyme-substrate (ES) structures showing an important role of coordination shells of magnesium ions in the solvent accessible active site. Several stable six-fold coordination shells of Mg<sub>A</sub><sup>2+ </sup>are observed in MD simulations of ES complexes. In the lowest energy ES conformation, the coordination shell of Mg<sub>A</sub><sup>2+ </sup>does not include the O<sub>δ1</sub> atom of the conserved Asp440 residue. Starting from this conformation, a one-step reaction mechanism is characterized which includes proton transfer from the ribose O<sup>3'</sup>H<sup>3' </sup>group in ATP to Asp440 via a shuttling water molecule and P<sup>A</sup>-O<sup>3A</sup> bond cleavage and O<sup>3'</sup>-P<sup>A</sup> bond formation. The energy profile of this route is consistent with the observed reaction kinetics. In a higher energy ES conformation, Mg<sub>A</sub><sup>2+</sup> is bound to the O<sub>δ1</sub>(Asp440) atom as suggested in the relevant crystal structure of the protein with a substrate analog. The computed energy profile initiated by this ES is characterized by higher energy expenses to complete the reaction. Consistently with experimental data, we show that the Asp440Ala mutant of the enzyme should exhibit a reduced but retained activity. All considered reaction pathways include proton wires from the O<sup>3'</sup>H<sup>3' </sup>group via shuttling water molecules. </p>

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