The rate of scavenging by Ehrlich ascites cells of anionic ascorbyl and 2,6-dimethoxy-p-semiquinone free radicals has been investigated by electron spin resonance spectroscopy both for viable cells and for subcellular fractions obtained by differential centrifugation. The scavenging activity is concluded to be associated with an NAD(P)H enzyme containing an active sulfhydryl group. Attempts to ...

The common method used in the food industry to manufacture pea protein isolate (PPI) is extraction by alkaline extraction?isoelectric precipitation, followed spray drying. In this study, effect of adding a co-spraying agent PPI at ratio 10:90, trehalose (Tr), sucrose (Su) or sodium hexametaphosphate (SHMP), on structure, functionality and aromatic profile spray-dried was studied. Results showed...

A nuclease has been isolated from an acid homogenate of chicken pancreas and purified over 300-fold. The purified preparation was free of phosphomonoesterase and phosphodiesterase activity, but rapidly hydrolyzed ribonucleic acid and deoxyribonucleic acid. The enzyme which by several criteria was a single protein required Mg++ or Mn++ for activity; addition of excess ethylenediaminetetraacetate...

A plant single-chain ribosome-inactivating protein derived from the root tuber of Trichosanthes kirilowii, termed trichosanthin (TCS), was modified with 2-iminothiolane. It was not like trichokirin, a ribosome-inactivating protein derived from the seeds of the same plant, in that TCS retained full activity when 1.5 sulfhydryl groups were introduced into each TCS molecule by 2-iminothiolane modi...

Isotopic exchange of (35)S between penicillins and 6-amino-penicillanic acid (6-APA) was observed in cell-free extracts of Penicillium chrysogenum. Sulfhydryl-containing compounds were required for activity. Dithiothreitol, dithioerythritol, mercaptoethanol, and glutathione served as activators. The acyltransferase was purified threefold by adsorption on calcium phosphate gel at pH 6 and elutio...

The modification of avian phosphoenolpyruvate carboxykinase by a variety of sulfhydryl reagents leads to inhibition. The inhibition is related to the loss of 1 highly reactive cysteine residue of the 13 cysteines present in the enzyme. Inhibition by reagents which yield a mixed disulfide was rapidly reversed by thiols. Reagents specific for vicinal sulfhydryl configurations were not potent inhi...

The discovery of captopril, the prototype of orally active angiotensin-converting enzyme inhibitors (ACEIs), represented a major breakthrough in the treatment of cardiovascular diseases. Currently, captopril has four important indications: hypertension, congestive heart failure, acute myocardial infarction, and diabetic nephropathy. After the discovery of captopril, several new ACEIs were devel...

Peroxynitrite (ONOO-) toxicity is associated with protein oxidation and/or tyrosine nitration, usually resulting in inhibition of enzyme activity. We examined the effect of ONOO- on the activity of purified rat liver microsomal glutathione S-transferase (GST) and found that the activity of reduced glutathione (GSH)-free enzyme was increased 4- to 5-fold by 2 mM ONOO-; only 15% of this increased...

BACKGROUND Although disulfide bond formation in proteins is one of the most common types of post-translational modifications, the production of recombinant disulfide-rich proteins remains a challenge. The most popular host for recombinant protein production is Escherichia coli, but disulfide-rich proteins are here often misfolded, degraded, or found in inclusion bodies. METHODOLOGY/PRINCIPAL ...

INTRODUCTION The aim of the study was to assess the influence of the nitric oxide synthase inhibitor L-NAME and the endothelin receptor blocker BQ123 on the free sulfhydryl (-SH) groups content in rat lung homogenates. MATERIAL AND METHODS Experiments were performed on Wistar-Kyoto rats divided into the following groups: group I (control) received (i.v.) saline; group II (ET-1) received (i.v....