Apyrases

Apyrase (isoenzyme of high ATPase/ADPase ratio, potato)[7] S-Aryltransferase (sheep liver... 

Young I can explain ATP. I did these experiments looking at intercellular Ca2+ waves and apyrase, and there is no effect. It turns out that the presence of either a prostaglandin transporter blocker, which is the same class as a Cl channel blocker, or a prostaglandin synthesis inhibitor, interrupts intracellular Ca2+ that is far away. It does not interrupt the intercellular Ca2+ through the gap junctions there are two different mechanisms. 

Somlyo Why do you need the apyrase Doesn t the human uterus have enough ecto-ATPase There is a lot of ecto-ATPase in most smooth muscles. Is it not high in human uterus ... 

The levels of extracellular adenosine could increase step-wise up to micromolar levels as the outcome of the transport and/or diffusion of intracellular adenosine, formed from the large pools of intracellular ATP in hypoxic conditions (Sitkovsky et al. 2005,2008). Hypoxia can upregulate an adenine nucleotide-metabolizing ecto-enzyme cascade comprising ecto-ATP apyrase (CD39) and CD73 (Synnestvedt et al. 2002). 

Zhang, X., Malhotra, R., and Guidotti, G. (2000). Regulation of yeast ecto-apyrase yndlp by activating subunit Vmal3p of the vacuolar H+-ATPase. J. Biol. Chem. 275, 35592-35599. 

O Meara D, et al. SNP typing by apyrase-mediated allele-specific primer extension on DNA microarrays. Nucleic Acids Res 2002 30(15) e75. 

P. S. Krishman (1952). Apyrase, pyrophosphatase and metaphosphatase of Penicillium chrysogenum. Arch. Biochem. Biophys., 37, 224-234. 

P. Krishnan and V. Bajaj (1953a). The polyphosphatase of Aspergillus niger. I. The nonidentity of metaphosphatase with apyrase and pyrophosphatase. Arch. Biochem. Biophys., 42, 174-186. 

Blood is drawn from healthy adult volunteers, who had no medication for the last two weeks. Venous blood (8.4 ml) is collected into 1.4 ml ACD-solution and centrifuged for 10 min at 120 x g. The platelet-rich plasma (PRP) is carefully removed, the pH adjusted to 6.5 with ACD-solution and centrifuged at 285 x g for 20 min. The resulting pellet is resuspended in Tyrode s buffer (approx. 500 xl buffer/10 ml PRP). The platelet suspension is applied immediately to a Sepharose CL 2B column equilibration and elution at 2 ml/min flow rate is done with Tyrode s buffer without hirudin and apyrase. Platelets are recovered in the void volume. Final platelet suspension is adjusted to 4 x 108/ml. Gel-filtered platelets (GFP) are kept at room temperature for 1 h until the test is started. 

NTPDases Nucleoside triphosphate diphosphohydrolases also known as apyrases,... 

ATPase the abseii( 0 of newly formed AMP adenosine monophosphate) shows it to be free of contaminations with apyrase or myokinase activities. In view of the finding that platelets contain both apyrase and myokinase, this latter observation seems particularly important. 

If neither hirudin nor apyrase can prevent TCIPA, then other mechanisms should be considered for the platelet aggregating activity of tumor cells, which might be disrupted by enzymatic treatments, such as fiypsin treatment (200 U/ml, 30-60 min at 37°C ... 

Pyrosequencing is a method to determine the nucleic acid sequence of short segments without the use of electrophoresis. A sequencing primer is hybridized to a single-stranded template that is usually generated by PCR. Four enzymes, a DNA polymerase, ATP sulfurylase, luciferase and apyrase, and two substrates— adenosine 5 phosphosulfate and luciferin— are included in the reaction mixture (Figure 37-17). One of the four dNTPs is added to the reaction (dATPaS is substituted for dATP because it is incorporated by the polymerase but is not a luciferase substrate). If the base is complementary to the template strand, DNA polymerase catalyzes its incorporation. Each incorporation event is accompanied by release of a pyrophosphate (PPi) so that the quantity of PPi produced is equimolar to the... 

---