Bernhard Huchzermeyer Botanisches Institut, Tierärztliche Hochschule, Bünteweg 17d, D-3000 Hannover 71, Bundesrepublik Deutschland Z. Naturforsch. 43c, 213-218 (1988); received July 27/November 19, 1987 Chloroplast, Coupling Factor, Binding Sites, ATPase, Phosphorylation A single binding site for phosphate was found on isolated chloroplast coupling factor in the absence of nucleotides. In our e...

Rauscher leukemia virus RNA-directed DNA polymerase has been purified to near homogeneity (greater than 90% pure) using affinity chromatography on polycytidylate-agarose with over 85% recovery of input enzymatic activity. The purified enzyme has a molecular weight of approximately 70,000 and appears to consist of a single polypeptide chain. The enzyme is free of DNase, but has RNase H activity....

1. The inhibition of hexokinase by glucose 6-phosphate has been investigated in crude homogenates of guinea-pig cerebral cortex by using a sensitive radio-chemical technique for the assay of hexokinase activity. 2. It was observed that 44% of cerebral-cortex hexokinase activity did not sediment with the microsomal or mitochondrial fractions (particulate fraction), and this is termed soluble hex...

(31)P Nuclear Magnetic Resonance (NMR) was assessed to investigate the phosphorus-containing compounds present in the tissues of the scleractinian coral Stylophora pistillata as well as of cultured zooxanthellae (CZ). Results showed that phosphorus-containing compounds observed in CZ were mainly phosphate and phosphate esters. Phosphate accounted for 19 ± 2% of the total phosphorus compounds ob...

Molecular mechanisms governing selective binding of a huge number of various phosphorylated protein partners to 14-3-3 remain obscure. Phosphate can bind to 14-3-3 and therefore being present at high intracellular concentration, which undergoes significant changes under physiological conditions, phosphate can theoretically regulate interaction of 14-3-3 with phosphorylated targets. In order to ...

The role of the parathyroid hormone in the regulation of calcium and phosphate metabolism has been recognized for many years (1). At the cellular level, the hormone is thought to regulate calcium and phosphate transport reactions. It is now known to (a) increase calcium reabsorption in the renal tubule (2, 3), (b) increase the transport of calcium across intestinal membranes (a, 5), (c) increas...

The glycerol-3-phosphate (G3P) transporter, GlpT, from Escherichia coli mediates G3P and inorganic phosphate exchange across the bacterial inner membrane. It possesses 12 transmembrane alpha-helices and is a member of the Major Facilitator Superfamily. Here we report overexpression, purification, and characterization of GlpT. Extensive optimization applied to the DNA construct and cell culture ...

Phosphoenolpyruvate was formed by rabbit liver mitochondria during incubations in the presence of dinitrophenol with oc-ketoglutarate and with other Krebs cycle intermediates as substrates. These intermediates, as indicated by experiments with labeled compounds, served as precursors for the carbon skeleton of the synthesized phosphoenolpyruvate. The phosphate, in the absence of exogenous supply...

Under resting conditions-that is, when metabolism is reduced to a minimum by chilling-previous experiments have indicated that sodium, potassium, inorganic phosphorus, and phosphate esters will not traverse the membrane of the red blood cell even when the concentrations of water, sodium, potassium, or inorganic phosphate in the serum are greatly altered (l-3). However, when the metabolic proces...