Effect of temperature on catalytic hydrogen currents of native and modified bovine serum albumin

1980 ◽  
Vol 45 (3) ◽  
pp. 669-678 ◽  
Author(s):  
Izaak Maurits Kolthoff ◽  
S. Kihara
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Temperature Effect ◽  
Bovine Serum ◽  
Effect Of Temperature ◽  
Catalytic Current ◽  
Catalytic Hydrogen ◽  
Increasing Temperature ◽  
Abnormal Temperature

The effect of temperature has been studied on three different catalytic hydrogen currents observed voltammetrically and on two of them polarographically with serum albumin and modified products of albumin adsorbed on mercury. The so-called "active cobalt catalytic current", ic and "presodium current", ips increase with increasing temperature. The temperature effect on the so-called Brdi_ka currents. i1 and i2 was found to be quite different from that on ic or ips. In ammoniacal buffer (pH = 9.3) in the presence of cobalt(III) or (II) i1 has been found virtually the same at temperature between 4° and 40°C, whereas i2 greatly decreases with increasing temperature. Evidence has been presented that in the presence of Co(III) or Co(II) and at 4°C all disulfide groups in the protein used are reduced to sulfhydryl at potentials at which i1 and i2 are observed. It has been concluded that the ligands of the protein which complex with Co(III) or Co(II) or Co(0) are different at potentials at which i1 is observed than at which i2 is observed. In order to account for the abnormal temperature effect on i2 it has been proposed that the area of the section of protein which is the seat of i2 is being detached from the surface with increasing temperature and that this process is reversible.

Temperature dependence of certain integrated membrane functions in macrophages

1982 ◽  
Vol 57 (1) ◽  
pp. 115-127
Author(s):  
M Faghihi Shirazi ◽  
N.N. Aronson ◽  
R.T. Dean
Keyword(s):  
Human Serum Albumin ◽  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Half Life ◽  
Bovine Serum ◽  
Fluid Phase ◽  
Peritoneal Macrophages ◽  
Turnover Time ◽  
Effect Of Temperature

We have studied the effect of temperature on uptake and degradation of molecules entering mouse peritoneal macrophages by fluid-phase, adsorptive and receptor-mediated pinocytosis, and on degradation of their intracellular proteins. Uptake of [3H]sucrose and uptake and degradation of formaldehyde-treated 125I-labelled human serum albumin and 125I-labelled mannose-bovine serum albumin continued, but were progressively slowed as the temperature decreased from 37 degrees C to 20 degrees C. The uptake and degradation were completely abolished at approximately 15 degrees C. Arrhenius plots for adsorptive and fluid uptake were unilinear, whereas that for receptor-mediated endocytosis showed an inflection point at approximately 20 degrees C. The results did not indicate any distinction between adsorptive and fluid pinocytosis. An ‘intracellular turnover time’ calculated for mannose-bovine serum albumin taken up by the specific route is 19–24 min and this time calculated for human serum albumin is, in contrast, 99 min. Studies of the kinetics of degradation of both endocytosed and endogenous proteins showed similarity in the temperature cut-off of degradation of endocytosed and endogenous long-half-life proteins (congruent to 15 degrees C) and continuance of endogenous short-half-life degradation at much lower temperatures.

Facilitation of Cleaning of Alumina Surfaces Fouled with Heat-Treated Bovine Serum Albumin by Ozone Treatment

2001 ◽  
Vol 64 (1) ◽  
pp. 108-112 ◽  
Author(s):  
HIROMI URANO ◽  
SATOSHI FUKUZAKI
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Room Temperature ◽  
Treatment Time ◽  
Ozone Treatment ◽  
Gaseous Ozone ◽  
Heat Treated ◽  
Ozone Pretreatment ◽  
Increasing Temperature

Facilitation of cleaning of alumina (Al2O3) particles fouled with heat-treated bovine serum albumin (BSA), which contains sulfhydryl groups on the molecule, by gaseous ozone was studied. With increasing temperature of heat treatment, the amount of adsorbed BSA onto Al2O3 surfaces increased, whereas the rate of BSA desorption during alkali cleaning decreased markedly, resulting in the larger amounts of BSA remaining on Al2O3 surfaces. No significant amounts of BSA were removed from Al2O3 surfaces by alkali cleaning alone when treated at temperatures above 120°C. Before alkali cleaning, the heat-treated, BSA-fouled Al2O3 at 150°C were treated with 0.05 to 0.30% (vol/vol) gaseous ozone at room temperature. Ozone pretreatment markedly accelerated the rate of BSA desorption during subsequent alkali cleaning. The effect of ozone pretreatment on BSA removal depended on the concentration of ozone and treatment time and hence on the total amount of ozone supplied. The molecular weight (MW) of desorbed BSA during alkali cleaning without ozone pretreatment coincided with the MW of the native BSA, whereas the MW of desorbed BSA during the combined ozone-alkali cleaning was lower than the MW of the native BSA. This indicated that the heat-treated BSA molecules adsorbed on Al2O3 were partially decomposed into some fragments by ozone pretreatment, resulting in the facilitation of the removal of BSA during alkali cleaning.

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