PubMed Health⌕ Search

Biomedical subjects

K A Moshkov

Publications and source records attributed to K A Moshkov.

At least 19 recordsLinked to original sources

Labile conformation of type 2 Cu2+ centres in human ceruloplasmin.

1. The investigation of human ceruloplasmin by spectral methods (EPR and spectrophotometry) demonstrated that type 2 Cu2(+)-containing centres occur not in one, but in two stable forms, differing in EPR and optical spectra. The differential optical spectra of these forms were recorded and the differences in molar absorption coefficients determined. 2. By the EPR method, it was shown that both forms of these centres exist in the blood serum of control donors, as well as in the serum of patients. The relative content of these forms depends on the organism physiological state or on the presence of some pathological condition. 3. The ferroxidase activity of ceruloplasmin against hemoglobin was proved spectrophotometrically. The involvement of other serum proteins in this process cannot be ruled out. The conformational state of ceruloplasmin molecules plays an essential role in its oxidase activity.

Binding Sites↗

[A novel form of copper-containing centers in human ceruloplasmin].

Using spectral methods (EPR, spectrophotometry), it was demonstrated that type II Cu2(+)-centers (so-called non-blue centers) are represented in human ceruloplasmin by two (but not one) stable forms which differ in their EPR spectra and absorption properties. Differential spectra were recorded, and the difference in the extinction coefficients of these forms was determined. Both forms were detected by the EPR method in blood sera from healthy and diseased individuals. The relative amount of these forms depends on the origin of the disease. This finding opens new perspectives in the diagnostic application of the EPR method. Spectrophotometric evidence of the ferroxidase activity of serum ceruloplasmin towards hemoglobin was obtained; other serum components were also shown to be involved in this process.

Ceruloplasmin↗

[Treatment of alcoholism by affective counterattribution].

A new narcopsychotherapeutic technique termed "affective counterattribution" (ACA) is offered to treat alcohol addiction. The use of ACA increased the effectiveness of alcoholism treatment that was ensured by association of strong pharmacogenic negative emotional experience coupled with bright hallucinatory images to notions of alcohol and alcohol-related stimuli. Alcoholic attitude was destroyed and the patients' pathological personality traits were corrected.

Abreaction↗

Electron microscope study on human ceruloplasmin.

Electron microscopy of human ceruloplasmin (CP) molecules revealed a few distinctive types of particle images. Analysis of these images allows to propose a tentative model for CP: six "subunits" (which we call domains) not much different in size are arranged with 32 point group pseudosymmetry. The determination of the number of polypeptides arising at the spontaneous specific proteolytic fragmentation of CP and their molecular weights conform with this assumption. The electrophoretic studies of the CP samples prepared both with and without potent proteolytic inhibitor, PMSF, revealed that CP is a single-chain protein with molecular weight of 130 000. Isolated and stored without PMSF the polypeptide chain of CP undergoes specific proteolytic cleavage which results in the appearance of polypeptides with molecular weights of 16 000, 48 000, and 64 000. The latter two polypeptides degradate to about two- and three-fold decreased molecular weights fragments, respectively. Therefore, the single polypeptide chain of CP contains at least five peptide bonds which are particularly susceptible to proteolytic attack and which connect six principal segments of the chain. The hydrolysis of these bonds results in liberation of the six fragments which were integrated in the enzymatically active globule of CP.

Ceruloplasmin↗

Preliminary X-ray crystallographic and physico-chemical investigations of human ceruloplasmin.

Single crystals of the plasma protein ceruloplasmin (CP) and its two modified forms: neuraminidase-treated CP (asialoCP) and NaN3-inhibited CP (NaN3-CP) suitable for X-ray studies have been grown. The native CP crystallizes as described previously by Magdoff-Fairchield et al. (1969) in the tetragonal space group 14 (a = b = 268.2 A, c = 129.1 A) with two protein molecules in the asymmetric part of a unit cell. AsialoCP crystals belong to the trigonal space group P 3(1)21 or P321 (a = b = 215.0 A, c = 84.5 A) and have one protein molecule in the asymmetric part of a unit cell. NaN3-CP crystals are isomorphous to crystals of native CP. Despite some differences in electrophoretic mobility and optical properties, the conformations of the native CP molecule and its modified forms are similar, as can be concluded from a study of ORD and CD spectra.

Azides↗

[Clinical polymorphism and ceruloplasmin variants in hepatolenticular degeneration].

The relationship between differences in the clinical polymorphism of hepatolenticular degeneration (Wilson's disease) and characteristics of CP (ceruloplasmin) structural changes were investigated. The comparative study of Wilson's disease patients revealed two forms of clinical development of this disease which differ from each other by the expression of the visceral symptoms preceding the establishment of the typical neurological picture. The peptide map analysis of tryptic hydrolysates of the CP from individual patients has demonstrated the altered peptide patterns in five cases. Clinical and genetic heterogeneity of Wilson's disease is discussed.

Adolescent↗

On the defect of synthesis ceruloplasmin in the liver polyribosomes in Wilson's disease.

Comparative immunochemical analysis of ceruloplasmin-synthesizing polyribosomes in liver biopsies from control subjects and homozygous carriers of the Wilson's mutation was performed. According to I125-antibody binding data, the amount of ceruloplasmin-forming liver polysomes in patients with Wilson's disease was 10--20 times lower than that in non-Wilson patients. Correspondingly, the pulse labeling of ceruloplasmin polypeptides was decreased several-fold in the cell-free liver preparations from patients with Wilson's disease.

Amino Acids↗

[Effect of ceruloplasmin conformation on its activity: significance for clinical analysis].

Conformational properties of ceruloplasmin were studied immediately in blood serum of healthy volunteers, patients with tuberculosis, with pulmonary cancer, with pneumonia and with Wilson-Konovalov disease. The glycoprotein conformation was found to depend on the volunteer physiological state and/or available pathology. The ceruloplasmin conformation and status of its copper-containing sites of the I type affected the enzyme oxidase properties and hence routine colorimetric procedures require some corrections for estimation of ceruloplasmin concentration and activity in blood serum.

Ceruloplasmin↗

[Ceruloplasmin activity and content of the blood of persons with acute and chronic alcoholic intoxication].

The concentrations of the enzymatically active and immunoreactive ceruloplasmin (CP) were determined in the blood serum of healthy men by means of the spectrophotometric and immuno-electro-photometric methods. Part of the total (immunoreactive) CP (15%), circulated in the blood channel in an enzymatically inactive state. The increase of the time of suffering from chronic alcoholism from 1 to 29 years leads to the growth of the concentrations of CP possessing enzymatic activity and of immunoreactive CP. The share of the enzymatically inactive protein remains practically constant. During acute alcohol intoxication there is a temporal drop of the C1 share in enzymatically active state with a constant concentration of the total protein in the blood serum.

Adolescent↗

[Localization of active sites in human ceruloplasmin from data of intra- and intermolecular homology].

The identification of possible copper ligands in human ceruloplasmin was carried out by the computer similarity analysis for sequences of ceruloplasmin and several other copper oxidases: azurin, plastocyanin, superoxide dismutase, tyrosinase and hemocyanin. It follows from the analysis of inter- and intramolecular homology that copper active sites of different types appeared to be in close contacts within the ceruloplasmin molecule.

Amino Acid Sequence↗