Carbonic anhydrase in human platelets.
نویسندگان
چکیده
The carbonic anhydrase activity of human platelets was investigated by measuring the kinetics of CO2 hydration in supernatants of platelet lysates by using a pH stopped-flow apparatus. An average carbonic anhydrase concentration of 2.1 microM was determined for pellets of human platelets. Analysis of the kinetic properties of this carbonic anhydrase yielded a Km value of 1.0 mM, a catalytic-centre activity kcat. of 130000 s-1 and an inhibition constant Ki towards ethoxzolamide of 0.3 nM. From these values, CO2 hydration inside platelets is estimated to be accelerated by a factor of 2500. When platelet lysates were subjected to affinity chromatography, only the high-activity carbonic anhydrase II could be eluted from the affinity column, whereas the carbonic anhydrase isoenzyme I, which is known to occur in high concentrations in human erythrocytes, appeared to be absent.
منابع مشابه
Study of Glycation Process of Human Carbonic Anhydrase II and Investigation of Effect of Fasting On Enzyme Activity by Using Spectroscopic Methods
Background: Glycation is the non-enzymatic reaction between the carbonyl groups in sugar and free amino groups in proteins. this reaction leads to changes in structure and functions of proteins. Advanced glycation end products (AGEs) is the final stage in this process, which is highly oxidizing and destructive nature, causing many diabetic complications. Methods: In the present investigation, ...
متن کاملpH Dependence Study of the Kinetic Reaction of Bovine Carbonic Anhydrase with 2,2'-Dithiobispyridine in the Absence and Presence of Surfactants
The pH dependence study reveals that the Cys 206 sulphydryl group of bovine carbonicanhydrase in the native form is not exposed. During the reaction of 2,2'-dithiobispyridine (2-DTP) with the enzyme, there was no absorbance change recorded. In the presence ofsurfactants, the pH dependence profiles of the apparent second order rate constants, kapp, forthe reaction of 2-DTP with bovine carbonic a...
متن کاملGas contaminants capturing by gamma-carbonic anhydrase catalyst: A quantum chemical approach
In this paper, we used quantum chemical approach to shed light on the catalytic mechanism of γ-carbonic anhydrase (γ-CA) to convert carbon dioxide to bicarbonate ion. Density functional theory (DFT) using B3LYP and UB3LYP functional and three split-valance including 6-31G*, 6-311G** and 6-311++G** basis sets were used to calculate the details of electronic structure and electronic energy of act...
متن کاملGas contaminants capturing by gamma-carbonic anhydrase catalyst: A quantum chemical approach
In this paper, we used quantum chemical approach to shed light on the catalytic mechanism of γ-carbonic anhydrase (γ-CA) to convert carbon dioxide to bicarbonate ion. Density functional theory (DFT) using B3LYP and UB3LYP functional and three split-valance including 6-31G*, 6-311G** and 6-311++G** basis sets were used to calculate the details of electronic structure and electronic energy of act...
متن کاملQuantitative Structure - Activity Relationships Study of Carbonic Anhydrase Inhibitors Using Logistic Regression Model
Binary Logistic Regression (BLR) has been developed as non-linear models to establish quantitative structure- activity relationships (QSAR) between structural descriptors and biochemical activity of carbonic anhydrase inhibitors. Using a training set consisted of 21 compounds with known ki values, the model was trained and tested to solve two-class problems as active or inactive on the basi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Biochemical journal
دوره 217 3 شماره
صفحات -
تاریخ انتشار 1984