Omeprazole (OME), a proton pump inhibitor used to treat gastritis, is also an aryl hydrocarbon receptor (AhR) activator. OME activates AhR in human hepatocytes and hepatoma cells, but not in mice in vivo or in vitro. We recently discovered that this species-specific difference results from a difference in a few amino acids in the ligand-binding domain of AhR. However, OME activates both mouse a...

We present a reproducible method for the preparation of nuclear extracts from the yeast Saccharomyces cerevisiae that support efficient RNA polymerase B (II)-dependent transcription. Extracts from both a crude nuclear fraction and Percoll-purified nuclei are highly active for site-specific initiation and transcription of a G-free cassette under the Adenovirus major late promoter. At optimal ext...

objective: punica granatum, commonly known as pomegranate, has emerged as a medicinal plant with potential antimicrobial activity. the present study was planned to evaluate this activity against both gram positive staphylococcus aureus (s. aureus) and negative pseudomonas aeruginosa (p. aeruginosa) bacteria as well as against pathogenic yeast, candida albicans (c. albicans). material and method...

Purpose: To investigate the antifungal activities.of the individual as well as the combined hydroalcohol leaf and root extracts of endemic Hypericum havvae A. Guner (Hyperiaceae). Methods: Each dry powdered plant material (20 g) was soaked in 150 ml of aqueous ethanol (50: 50 %v/v) until complete saturation of the plant material. After the extracts were filtered and evaporated, the antifungal a...

We have isolated the human protein SNEV as downregulated in replicatively senescent cells. Sequence homology to the yeast splicing factor Prp19 suggested that SNEV might be the orthologue of Prp19 and therefore might also be involved in pre-mRNA splicing. We have used various approaches including gene complementation studies in yeast using a temperature sensitive mutant with a pleiotropic pheno...

We report a cell-free system that measures transport-coupled maturation of carboxypeptidase Y (CPY). Yeast spheroplasts are lysed by extrusion through polycarbonate filters. After differential centrifugation, a 125,000-g pellet is enriched for radiolabeled proCPY and is used as "donor" membranes. A 15,000-g pellet, harvested from nonradiolabeled cells and enriched for vacuoles, is used as "acce...

This report details the procedural requirements for preparing cell-free extracts of yeast rich in polyribosomes. This enabled us to demonstrate the occurrence of polyribosomes in yeast, to show their role in protein synthesis, and to devise methods for their resolution and isolation. When certain precautions are met (the use of log phase cells, rapidly halting cell growth, gentle methods of dis...

Glycero-3-phosphocholine (GPC), the product of the complete deacylation of phosphatidylcholine (PC), was long thought to not be a substrate for reacylation. However, it was recently shown that cell-free extracts from yeast and plants could acylate GPC with acyl groups from acyl-CoA. By screening enzyme activities of extracts derived from a yeast knock-out collection, we were able to identify an...

The yeast Cdc7 function is required for the G1/S transition and is dependent on passage through START, a point controlled by the Cdc28/cdc2/p34 protein kinase. CDC7 encodes a protein kinase activity, and we now show that this kinase activity varies in the cell cycle but that protein levels appear to remain constant. We present several lines of evidence that periodic activation of CDC7 kinase is...

The investigations reported here evolved from studies on a coupled aerobic reaction between cysteinesulfinic acid (CSA)’ and a substance obtained from yeast extracts, which was catalyzed by soluble preparations from Proteus vulgaris and a variety of animal tissue, and yielded equal amounts of aspartate, pyruvate, and sulfate as products (2, 3). The reaction required DPN and an autoxidizable dye...