Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method of electrophoresis of nuclear 30S particles is described. In contrast to the earlier methods based on the fixation of RNP particles with formaldehyde and bifunctional agents with subsequent treatment with sodium dodecylsulphate, the new method treats intact particles in the presence of 1% triton X-100. One of the advantages of the proposed method is the possibility of using the polyacrylamid gel electrophoresis with high resolution capacity in addition to agarose gel electrophoresis. The developed method gives a possibility to estimate the homogeneity and nativity of RNP particles without additional separation by sucrose gradient or purification in nuclear extracts. There is a correlation between the distribution of the particles in the sucrose gradient and the picture of the mobility of these particles in agarose gel.
Mol Biol (Mosk)
PMID:[Homogeneity of the 30S fraction of nuclear ribonucleoprotein particles. Electrophoresis of intact particles]. 707 Mar 73

The reaction between formaldehyde and protein has been studied with the use of a radioactive indicator. In the presence of excess formaldehyde the reaction is kinetically of the first order. The accordance of experimental results to the kinetic scheme of a biphasic process was shown. On this basis experimental and veritable rate constants, equilibrium constants of mono- and dimetilol derivatives formation, the energy of activation and pseudothermodynamic parameters were determined. The dependence of reaction rate and degree of protein modification from formaldehyde concentration and temperature are discussed. Given results permit to optimize and control the process of interaction between formaldehyde and proteins.
Mol Biol (Mosk)
PMID:[Kinetics of the reaction between formaldehyde and proteins]. 727 62

We studied the kinetics of formaldehyde dissociation from hydroxymethylated amino groups of nitrous bases on native DNA. Compared with monomers, the rate constant of formaldehyde dissociation from such bases integrate in the double helix proved to be 20 times smaller for adenine and 4 times smaller for cytidine within the temperature range of 15 to 40 degrees C. The kinetic pattern suggests that the dissociation of formaldehyde from hydroxymethylated amino groups does not occur in the direction of the base plane nor through a full fluctuational opening of base pairs. It is presumed that formaldehyde dissociation from modified amino groups is due to softer fluctuational changes which however, make it possible for formaldehyde to attack amino groups perpendicularly to the base plane.
Mol Biol (Mosk)
PMID:[Kinetics of formaldehyde splitting off from the hydroxymethylated amino groups of nitrogen bases incorporated into double-helical DNA]. 738 35

It is shown that whole cells can be effectively fixed in the presence of formaldehyde at -12 degrees C. This reaction is used for the study of the native structure of chromatin. In the nuclei isolated from fixed cells the chromatin has the nucleosomal structure. The size of nucleosomal DNA in these nuclei estimated by hydrolysis with staphylococcal nuclease does not differ significantly from repeat length in the nuclei fixed after isolation or in non-fixed nuclei. However it is shown that mono- and oligonucleosomes in the nuclei from fixed whole cells are significantly more stable to the exonucleolytic degradation than in either nuclei fixed after isolation or non-fixed nuclei. The results suggest that the nuclei isolation does not appreciably affect the chromatin structure. The fixation of whole cells by formaldehyde in frozen suspension can be used also to study the structure of other cellular components and macromolecular complexes directly in the whole cell.
Mol Biol (Mosk)
PMID:[Length of nucleosomal DNA repeat in whole cells, fixed by freezing in the presence of formaldehyde]. 740

In this review an attempt is made to highlight the structures and properties of clay that may contribute to a better understanding of the role of clays in chemical evolution. The adsorption of organic molecules on clays has been demonstrated, as has the synthesis of bioorganic monomers in the presence of clays. For instance, amino acids (glycine, aspartic acid, threonine, alanine and others) as well as purines and pyrimidines, have been obtained from CO and NH3 in the presence of clays at relatively high temperatures (250-325 degrees C). Carbohydrates are also easily derived from formaldehyde at relatively low temperatures (approximately equal to 80 degrees C). The oligomerization of biochemical monomers, mediated by clays has also been shown to result in the formation of polymer molecules basic to life. For instance the condensation of amino acyl adenylates at room temperature in the presence of montmorillonite is known to yield polypeptides in discrete ranges of molecular weights with degrees of polymerization up to 56. Clays have also been found to affect the condensation of mononucleotides to oligonucleotides. Although the role of clays in the origin or metabolic pathways has not been demonstrated, it is possible that clays may have played a cooperative role with catalytic peptides in an intermediate stage of prebiological chemistry preceding the emergence of life on this planet.
J Mol Evol 1980 Aug
PMID:Clays in prebiological chemistry. 741 54

We have prepared a [32P]-labeled oligonucleotide probe carrying a ureido (-NH-CO-NH2) function at its 3'-terminus. This labeled oligomer was used to study polycondensations of urea and formaldehyde and of various phenols and formaldehyde in aqueous solution. The formation of formaldehyde copolymers attached to the amido-function of the probe was monitored by gel electrophoresis. Our results are generally in agreement with those obtained using conventional techniques. Our method is suitable for monitoring potentially prebiotic polycondensation reactions involving formaldehyde.
J Mol Evol 1995 Feb
PMID:Oligonucleotides as probes for studying polymerization reactions in dilute aqueous solution: II. Polycondensations. 769 17

Autoradiography of 32P-labeled cDNA, fractionated at high resolution by electrophoresis through thin (0.8-1.5 mm) vertical alkaline agarose gels, provides a sequence-independent screening procedure for gene family homologs. A screen of tissues of a marine mollusc revealed a prominent intestine-specific cDNA encoding a pancreatic serine protease homolog, which was not detectable as a discrete poly(A)+ RNA species on formaldehyde agarose gels. Discrete cDNA products are authentic, non-truncated transcripts of tissue-specific mRNA. A band-sharpening effect is imparted to cDNA products due to (a) substitution of a uniform length 5'-oligo(dT) terminus for heterogeneous 3'-poly(A) termini and (b) the inherent superior resolution of alkaline-denatured DNA.
Comp Biochem Physiol B Biochem Mol Biol 1995 Jan
PMID:Sequence-independent detection of gene family homologs: identification of a transcript encoding a molluscan serine protease homologous to the pancreatic enzymes of vertebrates. 785 51

Very little is known about the structural composition of the restenotic plaque in evolution. The responses of atherosclerotic femoral arteries of rabbits to balloon angioplasty (BA), thallium/holmium/chromium: YAG infrared laser angioplasty (LA), combined LA and BA, or no angioplasty were compared by blinded quantitative histomorphometry and angiography. The endothelium was injured by nitrogen/air desiccation, and the animals were fed a 2% cholesterol diet for 1 month prior to the angioplasty procedure. Animals were sacrificed 2 hr or 28 days after angioplasty by pressure perfusion with 10% formaldehyde (100 mm Hg), and arterial segments (4-5 cm) were excised bilaterally. The frequency of thrombus was greatest in arteries with LA. Arteries with combined LA and BA had the greatest initial gain in luminal diameter by angiography, but they also had the greatest reduction in luminal diameter from 2 hr to 28 days and the greatest cross-sectional area narrowing by plaque at 28 days. The principal component of the intimal plaques in all groups was fibrous tissue (approximately 90%), with the remainder consisting primarily of "foam cells." By multiple regression analysis, the strongest predictors of cross-sectional area narrowing were contiguity of foam cells between the intima and media, depth of the tear, percentage of foam cells in the plaque, and the intervention of LA followed by BA. The principal predictors of foam cells in the plaque, irrespective of treatment, were also cross-sectional area narrowing, contiguity of foam cells between plaque and media, and the depth of tear. It is suggested that a large proportion of the foam cells of the intima may be derived from foam cells of the media and adventitia rather than from the lumen. These observations may be of particular importance regarding angioplasty in young people where foam cells occupy a significantly greater proportion of the atherosclerotic plaque.
Exp Mol Pathol 1993 Dec
PMID:Response of femoral arteries of cholesterol-fed rabbits to balloon angioplasty with or without laser: emphasis on the distribution of foam cells. 813 4

Cell lines derived from formaldehyde-induced nasal tumors in Fischer 344 rats were established. All of the lines were found to be epithelial and aneuploid and to express keratin, transforming growth factor-alpha, and epidermal growth factor receptor transcripts. Two of four lines were tumorigenic upon injection into nude mice, and these lines also contained point mutations in the p53 suppressor gene. The data indicate that these lines possess characteristics that make them a valuable tool for the study of chemically induced respiratory tract carcinogenesis.
Mol Carcinog 1994 Apr
PMID:Characterization of cell lines derived from formaldehyde-induced nasal tumors in rats. 814 52

A better understanding of the mechanism of lipid peroxidation during the metabolism of cyclosporine A (CsA) might help explain the toxicities of this immunosuppressive drug on various organs. Our in vitro work used microsomes prepared from livers of phenobarbital-induced male rats. The incubations (total volume 1ml) also contained a NADPH regenerating system and substrate (i.e., CsA, carbon tetrachloride, or aminopyrine) dissolved in ethanol. Lipid peroxidation was inferred from the presence of malondialdehyde (MDA) which was detected by the thiobarbituric acid assay. The formation of CsA hydroxylated metabolites (AM9 and AM1) was monitored by liquid chromatography. The activity of the microsomal incubation was confirmed by measurements of MDA and formaldehyde production caused by increasing concentrations of CsA, carbon tetrachloride, and aminopyrine. The occurrence of hydroxylated metabolites was not coupled to the production of MDA. Aminopyrine could inhibit MDA production by CsA, but CsA could not reduce the formation of formaldehyde by aminopyrine. Erythromycin, a competitor for the binding site of CsA on cytochrome P450, reduced MDA production by CsA, and CsA inhibited formaldehyde production by erythromycin. Interaction studies with SKF 525A, ketoconazole, superoxide dismutase, catalase, alpha-tocopherol, and reduced glutathione confirmed the role of cytochrome P450 and the presence of activated oxygen species as a source of microsomal peroxidation which in return may explain the inhibitory effect of CsA on cytochrome P450 itself.
Mol Cell Biochem 1993 May 26
PMID:Generation of oxygen free radicals during the metabolism of cyclosporine A: a cause-effect relationship with metabolism inhibition. 823 41


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