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)

An ELISA was developed to quantitate the level of antibodies to various cell surface antigens of the Gram positive bacterium, Streptococcus mutans. Whole cells and purified cell wall components of S. mutans, lipoteichoic acid (LTA) from Streptococcus pyogenes, and dextran T 2000 were employed as coating antigens in this study. Cell walls of S. mutans were purified by mechanical disruption of whole cells followed by differential centrifugation and proteolytic enzyme treatment. Serotype-specific carbohydrate was purified from an autoclaved, lyophilized S. mutans whole cell preparation by column chromatography. LTA was prepared by Sepharose 4B chromatography of a phenol-water extract of S. pyogenes and used for detection of anti-polyglycerophosphate (PGP) antibodies. A rabbit antiserum to S. mutans 6715 (serotype g), which precipitated with purified carbohydrate antigen (RR g), gave good reactions with purified cell walls and whole cells of S. mutans 6715, less activity with RR g and low activity to LTA and dextran when tested by ELISA. Adsorption of this antiserum with whole cells of S. pyogenes resulted in antibody activity with specificity only to the serotype carbohydrate. The specificity of the antibody for homologous coating antigen was RR g greater than cell wall greater than whole cells. An antiserum to S. mutans MT573 (serotype e) contained antibody predominantly to LTA, whereas, anti-S. mutans MT703 (serotype e) reacted with both dextran and LTA; however, the activity to LTA was removed by prior adsorption of the antiserum with S. pyogenes cells. This treatment did not alter the antibody activity to dextran. To establish the sensitivity of ELISA, a purified IgG anti-serotype carbohydrate antibody was prepared by adsorption of anti-S. mutans 6715 antiserum with a mutant of S. mutans which lacks serotype carbohydrate followed by adsorption and elution of specific antibodies from S. mutans 6715 whole cells. The minimum level of sensitivity of ELISA was 12.5 ng of IgG anti-serotype carbohydrate.
Mol Immunol 1983 Apr
PMID:An enzyme-linked immunosorbent assay (ELISA) for quantification of antibodies to Streptococcus mutans surface antigens. 640 1

An in vitro assay that depends upon the synthesis of prolactin by primary cultures of dispersed cells from immature rat pituitary cells was used to study the structural requirement for estrogen action. Two categories of estrogens were identified: full estrogens (agonists) and partial estrogens (partial agonists) with antiestrogenic actions against the effects of 0.1 nM estradiol (E2). All of the agonists [diethylstilbestrol (DES), dimethylstilbestrol (DMS), R2858, and RU16117] produced a dose-related increase in prolactin synthesis equivalent to E2, although potencies were different: E2 = DES = R2858 greater than RU16117 greater than DMS. Partial agonists [ICI 3188, tri(4-hydroxyphenyl)chloroethylene, and bisphenol] each had bis(4-hydroxyphenol) substitutions at the ethylene double bond and stimulated prolactin synthesis only to about 50% of the maximal response observed with E2. Trianisylchloroethylene was weakly active as a partial agonist, but at high concentration (10 microM) was able to decrease prolactin synthesis produced by 0.1 nM E2. Previous studies from these laboratories showed that triphenylethylene derivatives with a strategically located alkyl aminoethoxyside chain are complete E2 antagonists with no agonist activity. Two series of novel compounds were assayed to determine whether their structures would predict biological activity. LN2299, the cis geometric isomer of a triphenylbromethylene, was a full agonist with activity equivalent to zuclomiphene, the cis geometric isomer of clomiphene. Cyclofenyl was a partial agonist, but deacetylation to the diphenol increased partial agonist activity and potency. However, introduction of a single pyrrolidinoethylside chain into the deacetylated cyclofenyl increased antiestrogenic potency and completely suppressed the expression of agonist activity. Finally, LN2833, with a novel C(OH)CH3 side chain in the position normally occupied by the alkylaminoethoxyside chain of most antiestrogens, produced antiestrogen activity with no estrogen properties. Antiestrogenic potency was increased in LN2839 by a phenol in the triphenylethylene in a position equivalent to the 3-phenolic hydroxyl of E2. In general, the potency and biological properties could be predicted by reference to the structure of the molecule. Potent estrogens or antiestrogens have a phenolic hydroxyl in a position that would be equivalent to the 3-phenolic hydroxyl of E2. Partial agonist action is predicted by a 4-hydroxyphenol attached to the same carbon as the phenyl ring equivalent to the A-ring of E2.(ABSTRACT TRUNCATED AT 400 WORDS)
Mol Pharmacol 1984 Sep
PMID:Estrogen-stimulated prolactin synthesis in vitro. Classification of agonist, partial agonist, and antagonist actions based on structure. 654 Dec 93

Human term placenta RNA and polyadenylated mRNA were prepared using guanidine HCl and oligo (dT)-cellulose affinity chromatography. Both fractions translated in a wheat germ cell-free system showed, under optimal condition of K+ and Mg++ ions and spermidine, about 9 times activity for RNA and 15-25 times for poly(A+) mRNA greater than the control. Homogenization of the tissue at high speed compared to that at low speed improved 4-fold activity. Analysis of tritiated products by SDS-Polyacrylamide gel electrophoresis and detected by fluorography showed more than ten different intensity bands ranging between 12 and 66 kD. According to the results obtained, guanidine HCl is an advantageous procedure for the extraction of RNA from this nuclease-rich tissue compared with that obtained with phenol extraction, in both activity and in larger translation products.
Mol Biol Rep 1983 Aug
PMID:Translation in a cell-free system of mRNA from term placenta extracted by guanidine hydrochloride. 663 22

DNA isolated from rat liver by intensive deproteinization with chloroform/isoamyl alcohol and phenol contains low molecular weight peptides in a quantity of about 20 micrograms/mg DNA. These peptides show high specific activity in inhibiting transcription in a reconstituted cell-free system with prokaryotic and eukaryotic RNA polymerase. Their level is markedly decreased in DNA prepared from Novikoff hepatoma cells. Moreover the amino acid analysis and the pattern of analytical separation by high performance liquid chromatography (HPLC) show some biochemical differences between DNA-binding peptides extracted from rat liver and Novikoff hepatoma cells. The possibility that carcinogenesis may involve mechanisms which lead to selective removal of some components of the DNA-binding peptides, is discussed.
Mol Biol Rep 1983 Aug
PMID:DNA-binding peptides from rat liver and Novikoff hepatoma cells: quantitative level and possible biochemical differences. 668 24

The dispersion of dye molecules and small cations injected from a point source in the cytoplasm of molluscan neurons has been measured photometrically and compared with dispersion in aqueous solution. The diffusion of phenol red and arsenazo III was at least a factor of five slower in the cytoplasm than in saline. Movement of both dyes was slowed by about the same factor in a given cell. The dispersion rate of arsenazo III was not significantly affected by preloading the cytoplasm to dye concentrations up to 0.5 mM. Calcium and barium dispersion was measured in neurons and saline droplets preloaded with arsenazo III, while phenol red absorbance changes were used to follow the dispersion of injected protons. Ba2+ and H+ moved very slowly in the cytoplasm compared to aqueous solution. Ca2+ movement in all probability underwent a similar retardation in the neurons but high-affinity buffering of the cytoplasm severely restricted the spread of detectable amounts of this ion away from the injection site.
Cell Mol Neurobiol 1984 Mar
PMID:Diffusion of ions and indicator dyes in neural cytoplasm. 674 69

The role of various enzymes and biological molecules on the activation and deactivation of the metabolites of phenol was investigated in vitro. Phenol, the major metabolite of benzene, is metabolized to hydroquinone and catechol. Activation of these metabolites and deactivation of their oxidized forms was assessed by the amount of covalent binding to microsomal protein. [14C]Phenol and NADPH were incubated with hepatic microsomes isolated from phenobarbital-pretreated guinea pigs, and 2.33 nmoles of hydroquinone and 0.12 nmole of catechol were formed per minute per milligram of microsomal protein. Covalent binding of the metabolites to microsomal protein incubated with microsomes isolated from guinea pigs pretreated with phenobarbital was 252 pmoles bound/min/mg; with microsomes from untreated guinea pigs, covalent binding was 146 pmoles bound/min/mg. Covalent binding was inhibited greater than 90% with the addition of N-octylamine, ascorbate, or GSH. The addition of superoxide dismutase inhibited covalent binding with microsomes isolated from phenobarbital-pretreated guinea pigs 35% but did not inhibit it with microsomes isolated from untreated animals. Partially purified guinea pig hepatic DT-diaphorase [NAD(P)H (quinone acceptor) oxidoreductase, EC 1.6.99.2] inhibited covalent binding 70%. This effect was reversed in the presence of dicumarol, a specific inhibitor of DT-diaphorase. DT-diaphorase present in the 10(5) X g supernatant fraction was also active in inhibiting covalent binding but only after the removal of endogenous reduced glutathione. This effect could also be reversed by dicumarol. The addition of diaphorase (NADH:lipoamide oxidoreductase, EC 1.6.4.3) partially purified from Clostridium kluyveri inhibited covalent binding 86%. The addition of hydrogen peroxide and horseradish peroxidase (peroxidase, EC 1.11.17) or myeloperoxidase(s) increased covalent binding 30-fold and 6-fold, respectively. Ascorbate decreased this binding greater than 95%. These results indicate that hydroquinone, catechol, and phenol as well as their oxidized forms can be activated or deactivated by several of the above model systems. These systems may play a role in the myelotoxicity of benzene by modulating covalent binding.
Mol Pharmacol 1984 Jul
PMID:DT-diaphorase and peroxidase influence the covalent binding of the metabolites of phenol, the major metabolite of benzene. 674 27

Hepatic microsomal biotransformation of phenol to hydroquinone and catechol has been investigated with special reference to the covalent binding to microsomal protein of reactive metabolites formed during microsomal metabolism of phenol. Incubation of [14C]phenol with microsomes from phenobarbital-treated rat liver in the presence of an NADPH-generating system resulted in the formation of hydroquinone and catechol in the ratio of 20:1. No significant formation of 1,2,4-benzenetriol was observed. The biotransformation of phenol to both hydroquinone and catechol required NADPH and molecular oxygen. NADH was much less effective than NADPH as an electron donor and exhibited no significant synergistic effect when used together with NADPH. The biotransformation was inhibited by typical cytochrome P-450 inhibitors such as carbon monoxide, SKF 525-A, and metyrapone. These results indicated the involvement of cytochrome P-450 in the microsomal hydroxylation of phenol at both the ortho- and para-positions. Covalent binding of radioactivity to microsomal protein was observed when [14C]phenol was incubated with rat liver microsomes in the presence of an NADPH-generating system. The covalent binding was also found to require NADPH and molecular oxygen. Inclusion of cytochrome P-450 inhibitors in the incubation mixture resulted in a decrease in the covalent binding. These results indicated that at least one step in the metabolic activation of phenol to the metabolites responsible for covalent binding to microsomal protein was mediated by cytochrome P-450. Inclusion of N-acetylcysteine in the incubation mixture resulted in the complete inhibition of the covalent binding of radioactivity derived from [14C]phenol to microsomal protein, and there was a concomitant formation of N-acetylcysteine adducts of hydroquinone and catechol. These results indicated that hydroquinone and catechol were both precursors to reactive metabolites responsible for the covalent binding.
Mol Pharmacol 1983 Mar
PMID:Biotransformation of phenol to hydroquinone and catechol by rat liver microsomes. 683 3

Large plasmids of molecular weight varying from 90 to around 200 x 10(6) have earlier been detected in most Rhizobium meliloti strains using an alkaline denaturation - phenol extraction procedure. With a less destructive method (Eckardt 1978) it was possible additionally to detect one plasmid of molecular weight clearly greater than 300 x 10(6) (= megaplasmid) in all of twenty-seven R. meliloti strains of various geographical origins and nodulation groupings investigated. Four strains (RCR 2011, A145, S26 and CC2013) were found to carry one megaplasmid and no smaller plasmids. Hybridization experiments with Klebsiella pneumoniae and R. meliloti cloned nitrogenase structural genes D and H showed that these genes are located on the megaplasmid and not on the smaller plasmids. All of the ten independent spontaneous non-nodulating derivatives of three strains of R. meliloti were shown to have suffered a deletion in the nifDH region of the megaplasmid. These results indicate that a gene controlling an early step in nodule formation is located in the nifDH region of the megaplasmid. This indicates that the same replicon carries genes controlling early and late functions in symbiosis.
Mol Gen Genet 1981
PMID:Genes controlling early and late functions in symbiosis are located on a megaplasmid in Rhizobium meliloti. 694 1

Methods are described in this paper for obtaining and characterizing highly enriched preparations of ovine prolactin (PRL) and growth-hormone (GH) messenger RNAs. Purification steps include phenol extraction, oligo-(dT)-cellulose chromatography, sucrose-gradient ultracentrifugation, and polyacrylamide-gel electrophoresis. This sequence of procedures results in messenger preparations that are about 92% pure for prolactin mRNA and 78% pure for the growth-hormone mRNA species. Thus, these two closely related mRNAs can be isolated from the same tissue source at a purity adequate for cloning and nucleic acid hybridization experiments. Translation experiments with the cap analogue 7-methylguanosine, and end-labeling of the nucleic acid before and after beta-oxidation indicate that both messages possess blocked 5'-termini, and that these are part of previously described cap structures. Polyadenosine tracts of 30-160 residues were found at the 3'-ends of both purified species. Finally, sizing experiments suggest both mRNAs contain approx. 30% more bases than accounted for by the coding regions and the poly(A)-tracts. Their physical characteristics thus agree with those of most eucaryotic messages to date.
Mol Cell Endocrinol 1980 Mar
PMID:Isolation and characterization of ovine prolactin and growth-hormone messenger RNAs. 698 88

In the lower eukaryote Saccharomyces cerevisiae, 4,5,6-trichloro-2-(dichlorophenoxy)phenol and acridine orange cause different specific genetic alterations, either gene mutations or recombinations. These specific effects were used to characterize the mechanism of sister chromatid exchange (SCE) formation in human lymphocytes. Assuming that genetically active substances have comparable effects in lower and higher eukaryotes, the observations provide indirect evidence for a connection between induced mitotic recombination in yeast and SCEs in human lymphocytes and suggest that SCEs may be the consequence of a repair process.
Mol Gen Genet 1981
PMID:Correspondent reaction of mitotic recombination in yeast and sister chromatid exchange in human lymphocytes. 701 46


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