Laccase-Catalyzed Heterocoupling of Dihydroquercetin and p-Aminobenzoic Acid: Effect of the Reaction Product on Cultured Cells

Derivatization of the natural flavonoid dihydroquercetin with p-aminobenzoic acid was carried out in an ethyl acetate/citric buffer biphasic system using laccase from the fungus Trametes hirsuta. The main reaction product yield was ~68 mol %. The product was characterized by ¹H NMR, ¹³C NMR, and liquid chromatography-mass spectroscopy, and its structure was elucidated. The reaction product affected viability of cultured human rhabdomyosarcoma cells (RD cell line) in a dose-dependent manner and, therefore, can be of interest to pharmaceutical industry.

[The application of proteomic technologies for the analysis of muscle proteins of farm animals used in the meat industry (review)]

The review briefly summarizes the data on the development of proteomic technologies that became actively used in studies of the muscular proteins of farm animals used in the meat industry in 2006-2013. It has been noted that the main research trends are connected with the detection of changes in muscle proteins during post-mortem autolysis and the search for species-specific and other protein biomarkers. Particular publications regarding the development of methods based on proteomic technologies for monitoring the state of muscle proteins are considered. According to the analyzed data, we can conclude that the field is promising for the solution of a number of pressing problems in.applied biochemistry.

AGR2, ERp57/GRP58, and some other human protein disulfide isomerases

This review considers the major features of human proteins AGR2 and ERp57/GRP58 and of other members of the protein disulfide isomerase (PDI) family. The ability of both AGR2 and ERp57/GRP58 to catalyze the formation of disulfide bonds in proteins is the parameter most important for assigning them to a PDI family. Moreover, these proteins and also other members of the PDI family have specific structural features (thioredoxin-like domains, special C-terminal motifs characteristic for proteins localized in the endoplasmic reticulum, etc.) that are necessary for their assignment to a PDI family. Data demonstrating the role of these two proteins in carcinogenesis are analyzed. Special attention is given to data indicating the presence of biomarker features in AGR2 and ERp57/GRP58. It is now thought that there is sufficient reason for studies of AGR2 and ERp57/GRP58 for possible use of these proteins in diagnosis of tumors. There are also prospects for studies on AGR2 and ERp57/GRP58 leading to developments in chemotherapy. Thus, we suppose that further studies on different members of the PDI family using modern postgenomic technologies will broaden current concepts about functions of these proteins, and this will be helpful for solution of urgent biomedical problems.

[Study of Dj-1 protein in tissue specimens, cultured cells and serum of prostate cancer patients]

Two isoforms of Dj-1 protein were identified using a proteomic study in tissue specimens from two groups of patients with confirmed benign prostate hyperplasia (BPH) and prostate cancer (PCa). Dj-1 was also found in the cell lines PC-3, DU-145, LNCaP, BPH-1, and the lowest level of Dj-1 was found in BPH-1. Immunochemical study (ELISA) of serum levels of Dj-1, Bcl-2, IGF-1 and IGFBP-3 proteins revealed statistically significant distinctions between two groups of patients (p=0,004, Mann-Whitney test) only for Dj-1. Taken together, these data suggest that Dj-1 protein is a perspective biomarker candidate for PCa.

[The study of adaptation mechanisms of Yarrowia lipolytica yeast to alkaline conditions by means of proteomics]

Using proteomic technologies--two-dimensional electrophoresis in denaturing conditions in combination with mass spectroscopy of MALDI-TOF proteins--we demonstrated, for the first time, that the most noticeable alteration of protein composition of a Yarrowia lipolytica cell during adaptation to alkaline conditions was an increase of mitochondrial proteins relatively to proteins of cytoplasm.

[A study of protein profile changes in differentiating human myoblasts]

The changes in the protein profile in cultured human myoblasts after induction of differentiation was studied by proteomic techniques (a combination of O'Farrell two-dimensional electrophoresis and subsequent protein identification by MALDI-TOF MS and MS/MS analyses). Forty-one proteins have been identified, 25 of which were present in both proliferating and differentiating myoblasts, which allows them to be considered as myoblast housekeeping proteins. The changes in the distribution of some isoforms of tropomyosins, S100 proteins, cofilin, etc. have been revealed. The possible role of these changes in the cell protein profile in the realization of the program of skeletal muscle cell differentiation is discussed.

[Determination of "amino acids conflicts" and amino acids substitutions in primary structures of 41 human proteins by use the proteomic technologies]

Proteomic studies of some human tissues and organs (skeletal muscles, myometrium, motor zone of the brain, prostate), and also cultivated myoblasts revealed 41 of 300 identified proteins, in which the present of certain variants of amino acids ("conflicts") was recognized at several positions. Among the 93 registered amino acids "conflicts", seven cases represented the results of the protein polymorphisms caused by corresponding substitution of individual amino acid. Moreover, among prostate proteins the proteomic analysis revealed two isoforms of prostate-specific antigen, formed due to alternative splicing. Thus, our results have shown, that proteomic technologies allow to specify effectively the features of primary structures and to characterize various kinds of polymorphism in many human proteins.

[Age-related changes of albumin and actin of human myocardium]

In the human myocardium tissue, proteomic technologies revealed the products of 2 genes (alpha-actin and albumin), existing as fragments; their appearance and increased contents correlated with age. The age-related variants differ from the mature forms by the absence of N-terminal fragments of the amino acid sequences. In the chronic ischemic heart disease (CIHD), these age-dependent proteins were found in 50% of cases (in the age group 31-40 years), while in the control group such combination was detected only in 10% of the examined individuals. Subsequent studies in this field would probably reveal molecular mechanisms responsible for impairment and/or ageing of the cardiac muscle and also of the adaptation-dysadaptations mechanisms in the CIHD.

[New approaches to molecular diagnosis of prostatic cancer]

We compared prostatic proteins in patients operated for adenoma or cancer. 630 protein fractions were obtained from each tissue sample after fractionation by two-dimentional electrophoresis according to O'Farrell. Comparison of the samples from adenoma and cancer showed their difference by 7 proteins among which were isoforms of glyceraldehydes-3-phosphate-dehydrogenase, alpha-collagen and several little known proteins. Most of the cancer patients had the protein with molecular mass 19 kDa and isoelectric point 9.0. By the results of mass-spectrometry this protein was identified as androgen-induced secreted protein AGR2. This protein is considered a potential oncomarker. Prospects of some postgenome technologies for detection of new diagnostic markers of prostatic cancer are discussed.

[Identification of AGR2 protein, a novel potential cancer marker, using proteomics technologies]

A comparative analysis of the proteins in prostate tissues of the patients operated for hyperplasia (n = 7) or cancer (n = 5) was performed aiming to search for protein diagnostic markers. Differences in several minor proteins were detected using two-dimensional electrophoresis according to O'Farrel; among them, an additional protein with a molecular weight of 19 kDa and an isoelectric point of 9.0 was observed in four of the cancer cases. Mass spectrometry allowed this protein to be identified as the androgen-induced secreted protein AGR2. The possibility of using AGR2 as a diagnostic marker of prostate cancer is discussed.

[Gelatinase activity of protein fractions obtained by electrophoresis in polyacrylamide gel]

The modification of a method of determination gelatinolytic activity in protein fractions obtained by one and two-dimensional polyacrylamide gel electrophoresis is presented. The presence of a fraction 115-125 kD among human proteins of cortex matter and glomerulus of kidney and also in myocardium having gelatinolytic activity is demonstrated.

[Detection of differences in liver protein composition between recombinant strains of mice with different ThioTEPA sensitivities]

The sensitivity of recombinant mouse strains subjected to 23-27 generations of inbreeding to the clastogenic effect of thioTEPA (triethylene thiophosphoramide) was reestimated, and their characteristics were confirmed. Six 1XC3 recombinant strains were obtained from crossing strains 101/H x C3H/Sn, which differed from one another with respect to the sensitivity to thioTEPA. The protein composition of the liver tissue was studied in the recombinant strains by means of two-dimensional electrophoresis. Interstrain differences with respect to five liver proteins were found, which were correlated with the differences in the response to the mutagen.

[Two-dimensional electrophoresis of myocardial proteins in human cardio-vascular diseases]

The protein composition of human myocardium at some cardiovascular pathologies was studied by use of 2D electrophoresis. It was found that dilitation(al) cardiomyopathy and ischemia are both characterized by transferrin accumulation in myocardium and by enhanced expression of a protein with Mm 3 kD/pI 5. Besides that, at ischemic disease there was seen an elevation of the fetal isoform in the light chain of myosin. For one of the polymorphous protein systems, the occurrence rate changes were also recorded.

[DNA-methylase activity in human cardiac muscle. Association of DNA methylase activity with actin protein fractions]

The column isoelectrofocusing activity of the nuclear extracts of the human cardiac muscle has revealed at pH 3.5-8.2 5 peaks of DNA-methylase. When one of these peaks (II) was analyzed by the two-dimensional gel electrophoresis 6 proteins (10, 25, 35, 43, 67 and 120 kDa) were separated. 43 kDa protein had electrophoretic properties similar to actins and was able to methylate cytosine in the DNA molecules. The comparative computer analysis of the primary structure of human actins and several bacterial DNA-methylases has shown the homology of the extensive fragments of these molecules.

[Change in the composition of human skeletal muscles in amyotrophic lateral sclerosis]

Protein composition of human skeletal muscle impaired with lateral amyotropic sclerosis was studied by means of two-dimensional electrophoresis. Some protein fractions were altered. Characteristic property of all the preparations studied proved to be disappearance of three protein fractions of 35 kDa molecular mass and with pI 5.9, 6.0 and 6.1.

[Study of human lymphocyte proteins using two-dimensional electrophoresis]

Using O'Farrell 2DE modified method, a panel of human lymphocyte proteins have been studied. A 2-D map involving 273 fractions characterized in M(r)/pI coordinates has been developed. Some proteins were identified on the map and some comparability of experimental results to the Celis et al. data demonstrated. Ten protein fractions displaying some variability in a sample of 30 patients were revealed. A change in the amount of the E2 fraction M(r)/pI -51.0/5.70 was found among patients with chromosome 5 short arm deletion and translocation.

[A comparative analysis of the protein composition of human skeletal and cardiac muscle by two-dimensional electrophoresis]

Using a modified O'Farrell 2DE technique, the protein composition of human skeletal muscles was compared to that of human myocardium. The variability of protein composition was analysed in nine types of skeletal muscle tissue. A number of skeletal and heart muscles proteins were identified on the electrophoregrams. Both common and tissue-specific groups of muscle tissue polypeptides were revealed.

[Search for new products of gene expression in human cardiac muscle. Microsequencing of proteins after two-dimensional electrophoresis]

Proteins of the human heart muscle were studied using modified two-dimensional electrophoresis. After separation, proteins were electroblotted onto Immobilon P membranes and several protein spots were used for microsequencing analysis. In most cases the proteins analyzed have blocked N-terminal amino acids. In order to study the primary structure of these proteins, hydrolysis in situ by trypsin followed by reversed-phase HPLC and microsequencing of the resulting peptides were performed. Four protein were identified in 8 analyzed fractions, specifically myosin light chain 1 (MLCl-V/sB), fatty-acid binding protein (heart isoform), alpha (B)-crystallin and alpha-tropomyosin. Amino acid sequences of two proteins were not found among human amino acid sequences collected in SWISSPROT bank (v. 21).

[Human thyroid gland DNA methylase in nodular and diffuse goiter]

The heterogeneity and some properties of DNA-methylases isolated from nonmalignant human thyroid formations--nodular and diffuse goiters--have been studied. Isoelectrofocusing of methylase preparations produced 6-7 distinct activity peaks distinguished by pI, activity towards Ca2+ and Mg2+, sensitivity towards dithiothreitol and capacity to methylase cytosine into mono-, di- and tripyrimidine blocks in vitro. The degree of DNA methylation in vivo depended on the origin of of the goiter. Analysis of several methylase fractions by two-dimensional electrophoresis performed according to O'Farrell revealed the presence of major polypeptides having similar molecular masses (approximately 36 kDa). Besides the major component, all the preparations under study contained 6-10 characteristic minor components. The data obtained are suggestive of a structural and functional heterogeneity of human methylases.

[Study of autolytic changes in human myocardial proteins by two-dimensional electrophoresis]

Alterations of myocardial proteins were studied in the left ventricular tissue of adult persons and fetuses during natural autolysis. The most pronounced alterations were observed in proteins from regions of myosin light chains, region 119 and the region of muscle enzymes. When autolysis was studied in the myocardium and skeletal muscle, proteolytic alterations were observed in skeletal muscles later.

[The "major" proteins of the human myocardium in ontogeny]

Two-dimensional electrophoresis according to O'Farrell was used for studying changes in the content of major proteins of human myocardium at various stages of pre- and postnatal development. On the basis of the protein pattern specific of certain stages of myocardium differentiation the degree of development of the human cardiac muscle can be determined. The most pronounced changes in myocardium protein spectra are characteristic of the first half of pregnancy.

[Properties of mitochondrial porin from cattle heart]

Porin, a protein able to form ionic channels in model phospholipid membranes, has been isolated for the first time from bovine heart mitochondria. One-dimensional electrophoresis in the presence of sodium dodecyl sulfate revealed a major band with Mr of 32-34 kDa. On two-dimensional electrophoregrams this protein is represented by four components with pI ranging from 6.5 to 7.1. Porin spots were identified on two-dimensional electrophoregrams in a complete mixture of mitochondrial proteins. The presence of porin in bovine heart submitochondrial particles was demonstrated by two-dimensional electrophoresis.

[A new variant of myosin light chain 1 detected in human cardiac tissue]

Proteins from biopsy of human heart muscle (n = 250) were studied. The supplementary fraction was found in a material from an individuum that coincided in molecular mass but differed in pI from the light chain of myosin usually expressed in the ventricular tissue of the heart muscle (LCM-1 v). The two-dimensional electrophoresis and immunoblotting have shown this supplementary fraction to be a rare allele of LCM-1 v.

[Identification of alpha-tropomyosin of the human myocardium by two-dimensional electrophoresis, and sequencing]

Two-dimensional electrophoresis of total cardiac muscle extracts allows the detection of about 200 protein fractions. In preliminary studies the fraction D-10 protein was characterized in terms of relative molecular mass, isoelectric point and quantitative composition as alpha-tropomyosin. The similarity of the protein to human alpha-tropomyosin was confirmed by the results of analysis of the N-terminal sequence of the D-10 protein eluate in a gas-phase sequencer.

[Identification of myosin light chain 1 from human heart ventricles on two-dimensional electrophoretograms using monoclonal antibodies]

Two-dimensional electrophoresis performed according to O'Farrell was used to isolate the myosin light chain I from human heart ventricles. This chain was further used to obtain hybridomas able to secrete monoclonal antibodies. This method permits to increase the yield of monoclonal antibody-secreting hydridomas and to spare effort with regard to cultivation and testing of experimental samples.

[A two-dimensional map of proteins from left ventricle of the human heart]

A two-dimensional map of human heart left ventricular proteins for 213 polypeptide fractions has been constructed. A quantitative analysis of variability of the fraction position at 60 selected spots with the use of a CVIT computer system revealed a high reproducibility of the material distribution on electrophoregrams. Differences were found in the protein composition of eight heart muscle atrial and ventricular polypeptide fractions. Left ventricular proteins were shown to be represented by six electrophoretical variants. The methodological peculiarities of construction at the two-dimensional map of heart muscle proteins are discussed.

[The topographic characteristics and changes in the ontogeny of light-chain myosin in the human myocardium]

Pattern of myosin light chain in human atrium and ventricles was studied using two-dimensional electrophoresis. Minor fraction was found in ventricles and atria of adult man that coincided in molecular weight, isoelectric point and staining specificity with fetal myosin light chain. The 23 kDa and 24 kDa fractions of auricles were not detected in ventricles.

[Changes in the protein spectrum of human kidney anlagen]

Extracts of metanephros were studied using two-dimensional electrophoresis in human embryos at the age of 7 to 21 week of intrauterine development. Electrophoregrams show 160 to 190 protein fractions. Fractions have been identified which corresponded to actin, albumin, alpha-chain of tropomyosin, light chains of myosin. The tropomyosin zone fractions were subject to greatest changes during development. Other zones of the embryonic kidney electrophoretogram displayed, predominantly, quantitative changes of polypeptides.

[Human heart muscle proteins: two-dimensional electrophoretic analysis in embryos]

Human myocardium proteins synthesized in the course of heart muscle development have been analyzed by two-dimensional electrophoresis. The quantitative change was found in representation of the main retractable proteins in the course of the heart muscle formation (the light myosin chains, tropomyosin, etc.). Four polymorphous variants of myocardium proteins were found, one of which is, possibly connected with the defect in heart development.

[Analysis of the results of two-dimensional electrophoretic fractionation of proteins using a system of digital processing of video information]

Possible solution of four main problem in analysis of two-dimensional electrophoregrams using the complex set for processing of video-information SVIT is considered: I. a. potentiality for evaluation of correlation between integral optic density of spots on gel plates and amount of protein fractionated, 2. qualitative comparison of similar spots from various electrophoregrams, 3. the problem of overlapping spots, where the plane pictures of spots were transformed into three-dimensional system of peaks, 4. use of bench-marks for geometric transformations and production of unified pictures. The complex set or its modifications were able to settle these problems.

[Heart muscle proteins of an inbred mouse strain carrying the autosomal-recessive form of generalized myodystrophy]

The study of the polypeptide structure of cardiac muscle proteins of the inbred mice 129 Re + dy/dy by two-dimensional electrophoresis has revealed quantitative and qualitative variations in four polypeptides out of 161 analyzed ones. It is supposed that the protein fractions N 14 and O 13 may contribute to the development of cardiac pathology. Gene-dosage dependence is identified for the fraction O 13.

[The use of two-dimensional electrophoresis for the analysis of changes in the protein spectrum of the cardiac muscle during mouse ontogenesis]

Using two-dimensional polyacrylamide gel electrophoresis, an analysis of protein spectrum of cardiac muscle of C57BL/6Y mice in the course of ontogenesis was carried out. It was found that some genes expressed in the embryonic muscle are repressed in the course of differentiation. Seven major polypeptides were revealed during cardiac muscle growth. The methodological aspects of the use of two-dimensional electrophoresis are discussed.

[Study of human erythrocyte membrane proteins by 2-dimensional electrophoresis]

Fractionation of human erythrocyte membrane proteins was performed using a modification of two-dimensional gel electrophoresis described by P. O'Farrel with isoelectric point plotted against molecular mass. All major erythrocyte proteins, including high molecular weight proteins, such as spectrin and band 3 protein, identified by one-dimensional sodium dodecyl sulfate gel electrophoresis, were visualized by silver staining of two-dimensional gels. All in all about 50 polypeptides were distinguished on two-dimensional electrophoretic patterns. Preliminary protein map was developed.

[Detection of the interstrain polymorphism of heart muscle proteins in mice using two-dimensional electrophoresis]

Cardiac muscle proteins of four inbred murine strains were analyzed by one- and two-dimensional electrophoresis. Of those, 27 and 161 protein fractions were characterized in terms of molecular mass and relative electrophoretic mobility. The protein fractions were identified as corresponding to creatine phosphokinase, myoglobin and an albumin-like protein. Six polypeptides characterized by interlinear polymorphism were identified.

[Isolation and characteristics of highly-purified phenylalanine hydroxylase from the rat liver]

Electrophoretically homogenous phenylalanine hydroxylase was isolated from rat liver tissue using a number of methods involving affinity chromatography on phenyl-Sepharose, ion exchange chromatography on DEAE-Toyoperle and hydrophobic rechromatography on phenyl-Sepharose. Molecular mass of the enzyme was equal to 50,000 Da and Km = 4.4 X 10(-3) M with phenylalanine as a substrate. The enzymatic preparations were used for immunization of rabbits and the monospecific antiserum towards phenylalanine hydroxylase was produced.

[Oligomerization of phenylalanine hydroxylase during its activation with phenylalanine]

Activated and nonactivated forms of phenylalanine hydroxylase varied in the activity within the first minutes of the reaction initiated by means of a synthetic coenzyme 6,7-dimethyl-5,6,7,8-tetrahydropteridine. In activation of the enzyme by phenylalanine the degree of its oligomerization was altered. As shown by chromatography and ultracentrifugation nonactivated enzyme was a dimer with molecular mass 130,000 daltons, whereas the activated form was found to be tetramer of 260,000 daltons. H and L subunits of phenylalanine hydroxylase were equally important in organization of the tetramer. Activation of phenylalanine hydroxylase altered the enzyme affinity to hydroxyapatite. Thus, allosteric activation of phenylalanine hydroxylase occurred due to the enzyme oligomerization.