Studies of protein-bound (PB-SH) and nonprotein bound sulfhydryl group (NP-SH) concentrations in tissues under various conditions is a prerequisite to understanding the role of sulfhydryls in living organisms. Many methods have been developed for the measurement of sulfhydryl groups, but these have been concerned chiefly only with the estimation of NP-SH in biological fluids or total SH groups ...

Incubation of erythrocytes with the sulfhydryl reagent N-ethyl-maleimide (NEM) results in altered spectrin self-association and formation of dimers on the membrane. Skeletons isolated from these cells exhibit marked skeletal instability. In addition, NEM treatment induces increased thermal sensitivity of both cells and purified spectrin. These effects were not produced in aerobically incubated ...

A wide variety of molecular mechanisms have been proposed to explain the actions of the synthetic plant growth regulator maleic hydrazide (3). One of the most prominent of these theories holds that MH2 acts as a sulfhydryl reagent (7), and more recently it has been suggested that MH acts as a carbonyl reagent (12). The idea that MH might react with sulfhydryl groups was supported by reports tha...

The present paper is a continuation of studies on the reaction of cyanate with amino acids, peptides, and proteins (1). In the earlier report, emphasis was placed on the speed of the reaction of cyanate with the sulfhydryl groups of cysteine, glutathione, and urea-denatured P-lactoglobulin. The work to be presented in this communication is concerned primarily with a study of the cyanate-sulfhyd...

A large number of the antibiotics have demonstrated chemical reactivity toward compounds containing sulfhydryl groups (1, 2). There have also been observed marked differences in reactivity of individual antibiotics toward various types of sulfhydryl-containing compounds. In the present investigation, the effect of structure of thiol compounds on their ability to react with certain antibacterial...

Hardening of SD (8 and 12 hrs) and LD (18- and 24-hr photoperiods) cabbage plants in stages at temperatures starting with + 5 degrees and ending with - 3 degrees led to the following changes:Soluble protein plus nonprotein N showed a net increase only in the SD plants. In both SD and LD plants, it decreased to a minimum toward the end of the first stage of hardening, increased to a maximum in t...

Hemoglobins possess two very striking properties: they combine reversibly with oxygen, and this binding appears to be autocatalytic. Each molecule of vertebrate hemoglobin possesses four heine groups which combine reversibly with oxygen, and are so associated that the binding of oxygen by one heine greatly enhances the affinity of a second heine for oxygen. Two closely related proposals have be...

1. Cyanide inhibits the oxidation of the SH groups of cysteine and denatured egg albumin by the uric acid reagent. 2. At pH 4.8 cysteine is oxidized by the uric acid reagent and by ferricyanide in the presence but not in the absence of added copper sulfate. 3. In neutral solution, the uric acid reagent oxidizes the SH groups of denatured egg albumin in the presence of urea but not in the presen...

BACKGROUND Oils are often fried which reduces their beneficial biological and nutritional properties, contributing to disturbances in homeostasis. Some antioxidant substances can improve stability of oils. The aim of the study was to examine the effect of α-lipoic acid (ALA) on the concentration of sulfhydryl groups, lipid peroxides, malondialdehyde, creatinine and urea in serum of rats fed hig...

The present paper is a continuation of studies on the reaction of cyanate with amino acids, peptides, and proteins (1). In the earlier report, emphasis was placed on the speed of the reaction of cyanate with the sulfhydryl groups of cysteine, glutathione, and urea-denatured P-lactoglobulin. The work to be presented in this communication is concerned primarily with a study of the cyanate-sulfhyd...