In an earlier paper from this laboratory (1) there were described the characteristics of competitive inhibition resulting from the interference of certain aromatic compounds with the association of flavin adenine dinucleotide and the separated protein of n-amino acid oxidase. Included among the inhibitors were auramine, quinine, and various other quinolines and anilines. We now present our find...

The side effects associated with the usage of synthetic antidiabetic drugs make it imperative to search for alternative drugs from medicinal plants. Therefore, this study was aimed at evaluating the α-amylase and α-glucosidase inhibitory potential of Calotropis procera leaf, as well as its possible mode of inhibiting these enzymes. Acetone, aqueous and ethanolic extracts of C. procera leaf was ...

The DNA-dependent protein kinase (DNA-PK) is a serine/threonine protein kinase that is involved in mammalian DNA double-strand break repair. The catalytic subunit of DNA-PK (DNA-PKcs) shares sequence homology in its kinase domain with phosphatidylinositol (PI) 3-kinase. Here, we provide a detailed kinetic analysis of DNA-PK inhibition by the PI 3-kinase inhibitor wortmannin and demonstrate this...

Probenecid interacts with transport processes of drugs at several sites in the body. For most quinolones, renal clearance is reduced by concomitant administration of probenecid. The interaction between gemifloxacin and probenecid has not yet been studied. We studied the extent, time course, site(s), and mechanism of this interaction. Seventeen healthy volunteers participated in a randomized, tw...

BACKGROUND: The determination of cellular -galactocerebrosidase activity is an established procedure to diagnose Krabbe disease and monitor the efficacy of gene/stem cell– based therapeutic approaches aimed at restoring defective enzymatic activity in patients or disease models. Current biochemical assays for -galactocerebrosidase show high specificity but generally require large protein amount...

the effects of allopurinol, acyclovir and theophylline on the activity of adenosine deaminase (ada) were studied in 50 mm sodium phosphate buffer ph 7.5 at 27°c, using a uv– vis spectrophotometer. adenosine deaminase is inhibited by these ligands, via different types of inhibition. allopurinol, as a transition state analog of xanthine oxidase, and acyclovir competitively inhibit the catalytic a...

Androgen receptor (AR) inhibitors are used to treat multiple human diseases, including hirsutism, benign prostatic hypertrophy, and prostate cancer, but all available anti-androgens target only ligand binding, either by reduction of available hormone or by competitive antagonism. New strategies are needed, and could have an important impact on therapy. One approach could be to target other cell...

Unsaturated fatty acids present in the lipids of essential fatty acid (EFA)deficient rats were found to inhibit the oxygenase activity of sheep vesicular gland in an instantaneous, reversible manner. However, competitive inhibition by high levels of these acids cannot account fully for the reported loss of prostaglandin synthetic capacity of these EFA-deficient animals. A similar competitive in...

Transfer RNA inhibited the tyrosine-dependent ATPpyrophosphate exchange catalyzed by tyrosyl-tRNA synthetase from IIscherichia coli. The inhibition was specific for tRNATY’; it was competitive with tyrosine and noncompetitive with ATP. tRNA modified by periodate oxidation or by limited digestion with phosphodiesterase proved to be a stronger inhibitor of the enzyme than native tRNA; the inhibit...