Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) hybridization in formamide at low temperature was applied to hybridization of PhiX174 replicative form DNA and in vivo PhiX174 specific messenger RNA (mRNA) with some modification. We found that PhiX174 mRNA up to molecular weight 1.2 x 10(6) could be hybridized to and eluted from DNA without apparent breakage of phosphodiester bonds and th...

The isolation of adenosine tetraphosphate and pentaphosphate from samples of adenosine triphosphate has been reported by Marrian (1) and Sacks (2). The available evidence is consistent with a st,ructure in which the phosphate residues are linked by phosphoanhydride bonds to one another and are carried by the 5’-hgdroxyl group of the ribose moiety (l-4). During attempts to estimate guanosine tri...

We experimentally showed that biological molecular motor F$_1$-ATPase (F$_1$) implements an optimal rectification mechanism. F$_1$ hardly suppresses adenosine triphosphate (ATP) synthesis, which is the F$_1$'s physiological role while inhibiting unfavorable hydrolysis of ATP. This a high contrast to simple ratchet model, where inhibition backward current inevitably accompanied by suppression fo...

phosphate concentrations declined, indicating turnover of this compound. Incubation of LSI78Y cells in medium containing 0.5 ^M MMPR reduced intracellular concentrations of adenosine triphosphate, guanosine triphosphate, and adenosine diphosphate by about 70% and proliferation rates by about 30%. Upon transfer of such cells to M MPR-free medium, nucleotide levels and proliferation rates returne...

OBJECTIVES To examine possible modulators of the ion transport through the apical membrane of the nasal polyps. METHODS The study was conducted using the freshly-excised nasal polyps from the patients with chronic sinusitis. A voltage-sensitive vibrating probe technique was introduced to monitor the short-circuit current across the apical membrane of the polyp at 37°C. RESULTS In the presen...

BACKGROUND In human oocytes, as in other mammalian ova, there is a significant variation in the pregnancy potential, with approximately 20% of oocyte-sperm meetings resulting in pregnancies. This frequency of successful fertilization decreases as the oocytes age. This low proportion of fruitful couplings appears to be influenced by changes in mitochondrial structure and function. In this study,...

The observed standard free energy change (AGibs) for the hydrolysis of the terminal pyrophosphate bond of ATP has been experimentally determined under physiological conditions using an entirely new set of reactions. The observed equilibrium constant (K,,bs) for the combined reactions of acetate kinase (EC 2.7.2.1) and phosphate acetyltransferase (EC 2.3.1.8) has been determined at 38”, pH 7.0, ...

Extracellular ATP mediates proinflammatory and antiproliferative effects via activation of P2 nucleotide receptors. In contrast, its metabolite, the nucleoside adenosine, is strongly immunosuppressive enhances tumor proliferation metastasis. The conversion to adenosine catalyzed by ectonucleotidases, which are expressed on immune cells typically upregulated cells. present study, we identified s...

Both calcium and strontium could be transported actively from erythrocytes if adenosine triphosphate, guanosine triphosphate, or inosine triphosphate were included in the hypotonic medium used to infuse calcium or strontium into the cells. Acetyl phosphate and pyrophosphate were not energy sources for the transport of either ion. Neither calcium nor strontium transport was accompanied by magnes...