Escherichia coli tRNA has been fractionated on benzoylated DEAE-cellulose and DEAE-Sephadex to yield five purified tRNASer species. They differ in chromatographic behavior and in their coding properties. These tRNASer species are all charged by pure E. coli seryl-tRNA synthetase. Four of the tRNAs exhibit the same K, and V,,,,, in this reaction. For one of the tRNAs (the least pure) these param...

Major and minor ascorbate free radical (AFR) reductases, with diaphorase activity, and three other diaphorases were separated from the human lens soluble fraction by DEAE-cellulose ion-exchange column chromatography. They were characterized for adsorptivity to ion-exchange and 5'AMP-Sepharose 4B affinity columns, kinetic properties, and substrate specificity. The latter diaphorases were closely...

1. (Na+ +K+)-dependent ATPase was partially purified from eel gills by a procedure in which the microsomal fraction of crude preparations of chloride cells was selectively extracted with sodium dodecyl sulphate. 2. The microsomal specific activity was increased 2-fold during optimal treatment with detergent. 3. The final preparation (56% pure) had a specific activity of 341 mumol of ATP hydroly...

Affinity chromatography has been applied to the problem of specifically removing luteinizing hormone from sera used to supplement tissue culture media. Horse or fetal calf sera, passed through a column of an anti-luteinizing hormone immunoglobulin fraction linked covalently to agarose, were specifically depleted in their content of luteinizing hormone as seen by radioimmunoassay and by their ef...

Introduction: Current research effort at discovering effective anticataract agent is focus on evaluating Aldose reductase inhibition (ARI) capacities of medicinal plants and plant extracts. The present study was aimed at investigating the in vitro ARI activity of fractions of Lonchocarpus cyanescens leaves on partially purified AR from goat lens. Methods: Phytochemical constituents of the leave...

Previous work from our laboratory has demonstrated that neurohumoral stimulation of the exocrine pancreas is associated with the phosphorylation of the Mr 29,000 ribosomal protein S6. In a cell-free system using pancreatic postmicrosomal supernatant as the kinase donor, we found that the following co-factors stimulate the phosphorylation of the Mr 29,000 ribosomal protein: calcium with calmodul...

The phorbol diesters are the most potent inducers of differentiation of the promyelocytic leukemia cell line, HL-60. Soluble phorbol diester receptors from HL-60 cells were obtained from the cytosolic fraction and from the particulate fraction by either divalent ion chelation or detergent extraction. The partially purified soluble phorbol diester receptors required exogenous Ca2+ and phospholip...

A glutamate-binding protein was solubilized from rat brain synaptic plasma membranes using sodium cholate. Its properties were characterized after addition of exogenous phospholipids and formation of proteoliposomes. Glutamate binding was dependent on calcium and chloride ions with maximal binding at concentrations of 10(-5) M calcium and 10 mM chloride ions. The effects of the two ions were sy...

In an in vitro poliovirus replication system, purified viral polymerase, plus sense virion RNA, and a host factor have been previously shown to be necessary for the transcription of minus strands. We have found that a partially purified eukaryotic initiation factor-2 (eIF-2) fraction from rabbit reticulocytes can replace HeLa host factor in the replicase reaction. This enzyme preparation contai...

CoA-dependent transacylation activity in microsomes catalyzes the transfer of fatty acid between phospholipids and lysophospholipids in the presence of CoA without the generation of free fatty acid. We examined the mechanism of the transacylation system using partially purified acyl-CoA:lysophosphatidylinositol (LPI) acyltransferase (LPIAT) from rat liver microsomes to test our hypothesis that ...