The denaturation of ribonuclease A by guanidine hydrochloride, lithium bromide, and lithium chloride and by mixed denaturants consisting of guanidine hydrochloride and one of the denaturants lithium chloride, lithium bromide, and sodium bromide was followed by difference spectral measurements at pH 4.8 and 25 degrees C. Both components of mixed denaturant systems enhance each other's effect in ...

Staphylococcal enterotoxin types A and C, were observed by viscosimetry and near-ultraviolet difference spectroscopy to unfold at concentrations of aqueous guanidine hydrochloride greater than 1 M. Apparent rate constants of unfolding calculated from spectral curves differed markedly for the two enterotoxins. Rate constants for the unfolding of enterotoxin A in 2 or 3 M guanidine hydrochloride ...

The denaturation of ribonuclease A, lysozyme alpha-lactalbumin, and myoglobin by urea, guanidine hydrochloride, and guanidine thiocyanate has been followed with the use of difference spectral measurements. The free energy of stabilization (delta GH2OD) has been determined by the linear extrapolation of the free energy of denaturation to zero denaturant concentration. The values of delta GH2OD a...

Aminopeptidase P, a metalloprotease, targets Xaa-Proline peptides for cleavage [1-4]. There are two forms of human AMPP, a membrane-bound form (hmAMPP) and a soluble cytosolic form (hcAMPP)[5]. Similar to the angiotensin-I-converting enzyme, AMPP plays an important role in the catabolism of inflammatory and vasoactive peptides, known as kinins. The plasma kinin, bradykinin, was used as the subs...

background: the expression of mouse tumor necrosis factor alpha (tnf-α) in escherichia coli is a favorable way to get high yield of protein; however, the formation of cytoplasmic inclusion bodies, which is the consequence of insoluble accumulated proteins, is a major obstacle in this system. to overcome this obstacle, we used a pulsed dilution method to convert the product to its native conform...

1. The effects of regeneration of whole bovine albumin on antigenic activity and serological specificity were determined by precipitin measurements on rabbit antisera to (1) native whole albumin, (2) albumin regenerated from 8 M urea, and (3) albumin regenerated from 8 M guanidine hydrochloride. 2. While numerically the mean antibody response to these three antigens was found to decrease in the...

Ferrocytochrome b562 [Fe(II)cyt b562] folding can be triggered by photoinduced electron transfer to unfolded Fe(III)cyt b562 in 2-3 M guanidine hydrochloride solutions. The folding rates increase with decreasing guanidine hydrochloride; the extrapolated time constant for this folding process in the absence of denaturant (5 micros) is near the predicted value for intrachain diffusion. The relati...

Four synthesized biocidal guanidine hydrochloride polymers with different alkyl chain length, including polyhexamethylene guanidine hydrochloride and its three new analogs, were used to investigate their interactions with phospholipids vesicles mimicking bacterial membrane. Characterization was conducted by using fluorescence dye leakage, isothermal titration calorimetry, and differential scann...

Contributions of tyrosyl residues to trypsinand chymotrypsin-inhibitory activities in two homologous proteinase inhibitors were investigated by modifying them with N-acetylimidazole under various conditions. In Bowman-Birk soybean proteinase inhibitor, Tyr 55, immediately following the antichymotryptic site, Leu 53-Ser 54, is relatively inaccessible to N-acetylimidazole and can only be acetylat...

A new apoprotein has been isolated from delipidated human very low density lipoproteins by Sepharose 6B chromatography in 6 Y guanidine hydrochloride. This water-insoluble protein was noted to be unique to the plasma very low density and chylomicron fractions. This protein was shown to be homogeneous by urea-DEAE-cellulose chromatography, rechromatography in a guanidine-Sepharose system, sodium...