Various aspects of the interaction of oestrogen-receptor complexes with calf uterine chromatin covalently coupled to cellulose were analysed. Partially purified [3H]oestradiol-receptor complexes were bound to intact, or partially deproteinized, chromatin resins. Proteins were removed from the chromatin-cellulose resins by extraction with high molarities of salt, including NaCl/urea, guanidine h...

Kinetic and equilibrium studies of the folding and unfolding of the SH3 domain of the PI3 kinase, have been used to identify a folding intermediate that forms after the rate-limiting step on the folding pathway. Folding and unfolding, in urea as well as in guanidine hydrochloride (GdnHCl), were studied by monitoring changes in the intrinsic fluorescence or in the far-UV circular dichroism (CD) ...

We have earlier reported that both guanidine hydrochloride (GdnHCl)-induced and heat-induced unfolding of seed coat soybean peroxidase (SBP), monitored by far UV CD, show single step transition. However, although GdnHCl-induced unfolding follows a two-state pathway, the heat-induced denaturation proceeds through intermediates as indicated by the very low cooperativity of transition. In the form...

The denaturation of certain proteins is characterized in part by the appearance of titratable sulfhydryl groups (8,11, 13).’ Moreover, the proportion of these groups which appears in any one protein is dependent upon the method of denaturation employed (3,5,6). Proteins dissolved in solutions of urea, guanidine hydrochloride, and related substances show widely different amounts of sulfhydryl gr...

Fibrin, when formed from purified fibrinogen and thrombin, with the exclusion of either calcium or an unidentified serum factor (or both), can be dissolved in several rather mild reagents. Dissolution has been reported in dilute acid (1) and in moderately concentrated solutions of urea (2-5), guanidine hydrochloride (2-5), and histamine dihydrochloride (5). In urea, the dissolved particles have...

Catabolic dehydroquinase which functions in the inducible quinic acid catabolic pathway in Neurospora crassa has been purified 8000-fold. The enzyme was purified by two methods. One used heat denaturation of contaminating proteins; the other used antibody affinity chromatography. The preparations obtained by these two methods were identical by all criteria. The purified enzyme is extremely resi...

The potential use of the protein denaturant guanidine hydrochloride to inhibit selectively the enzyme activity of serum alkaline phosphatase isoenzymes from liver, bone, intestine, and placenta was investigated. Inhibition of each isoenzyme was shown to be dependent on time and concentration of inhibitor. In the presence of 0.3 mol/l (28.7 g/l) guanidine hydrochloride for 170 seconds 14%, 47%, ...

Submit Manuscript | http://medcraveonline.com classes of pyrimidines. The pharmaceutical importance of these compounds lies on the fact that they can be effectively used as analgesics, anti-inflammatory, anticonvulsant, insecticidal, herbicidal, antitubercular, anticancer and antidiabetic agents [4-6]. Also, the pyrimidine and aminopyrimidine structures are frequently-occurring motifs in commer...

The denaturation of certain proteins is characterized in part by the appearance of titratable sulfhydryl groups (8,11, 13).’ Moreover, the proportion of these groups which appears in any one protein is dependent upon the method of denaturation employed (3,5,6). Proteins dissolved in solutions of urea, guanidine hydrochloride, and related substances show widely different amounts of sulfhydryl gr...

The stability of two thermophilic esterases, AFEST from Archaeoglobus fulgidus and EST2 from Alicyclobacillus acidocaldarius, against the denaturing action of urea and guanidine hydrochloride has been investigated by means of steady-state fluorescence and circular dichroism measurements. Experimental results indicate that the two enzymes, even though very resistant to temperature and urea, show...