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)

Hydrocortisone hemisuccinate within 4 hours after in vivo administration produced an increase in precursor incoporation into rat thymus RNA and proteins in the whole animal. From these results, together with information obtained from measurements of the tyrosine aminotransferase activity and the action of mitomycin C administered one hour before the injection of hydrocortisone, it can be concluded that the increase in tissue level of the enzyme, consequent to hydrocortisone treatment, results from an increased rate of biosynthesis of the enzyme, which participates in the catabolic processes of proteins in glucocorticoid sensitive thymus cells.
Mol Cell Biochem 1975 Dec 31
PMID:L-tyrosine: 2-oxoglutarate aminotransferase induction by hydrocortisone in the thymus of the white rat. 0 Jun 10

1. A retrospective cross-sectional study was carried out on data derived from single 24 h urine collections from 246 male idiopathic calcium stone-formers. 2. The daily urine volume and pH and the exretions of calcium, oxalate, phosphate, creatinine and magnesium were related to the time of year when the urine was collected, and the saturation of urine with calcium oxalate and octocalcium phosphate calculated for each month. 3. There were significant seasonal variations in the urinary excretion of calcium and oxalate, each showing a maximum during the summer months and a minimum in the winter. There was no significant seasonal variation in urinary pH, volume, creatinine, phosphate or magnesium. 4. There was a significant increase in the saturation of urine with calcium oxalate and a trend towards higher saturation levels of octo-calcium phosphate in the summer. These changes were dependent only on the seasonal variation in urinary calcium and oxalate and not on urine volume. 5. A retrospective study of the seasonal incidence of stone episodes among these 246 stone-formers showed that the rate of stone passage per month was 50% higher in the summer than in the winter. There was no significant seasonal variation in the incidence of stones removed surgically.
Clin Sci Mol Med 1975 Dec
PMID:Seasonal variations in the composition of urine in relation to calcium stone-formation. 0 Nov 72

When solutions of nucleoside 5'-phosphates and trimetaphosphate are dried out at room temperature, nucleoside 5'-polyphosphates are formed. The Mg++ ion shows a superior catalytic function in this reaction when compared with other divalent metal ions. Starting with nucleoside 5'-phosphates, Mg++ and trimetaphosphate, the predominant products in the nucleoside 5'-polyphosphate series pnN are p4N, P7N and p10N. Nucleoside 5'-diphosphates yield p5N and p8N, nucleoside 5'-triphosphates give p6N and p9N. The prebiological relevance of these reactions is discussed.
J Mol Evol 1975 Dec 29
PMID:Formation of nucleoside 5'-polyphosphates from nucleotides and trimetaphosphate. 0 41

One of the major diagenetic pathways of organic matter in recent sediments involves the condensation of cellular constituents, particularly amino acids and sugars, into insoluble melanoidin-type polymers. These polymers consist mainly of humic and fulvic acids and make up the major part of the organic carbon reservoir in recent sediments. We suggest that a similar set of reactions between abiotically formed amino acids and sugars, and more generally between aldehydes and amines, occurred on a large scale in the prebiotic hydrosphere. The rapid formation of this insoluble polymeric material would have removed the bulk of the dissolved organic carbon from the primitive oceans and would thus have prevented the formation of an "organic soup". Melanoidin polymers have several properties which make them attractive hypothetical precursors of contemporary oxidation-reduction coenzymes: 1. they contain heterocyclic nitrogen compounds similar to the nitrogenous bases; 2. they contain a high concentration of stable free radicals; and 3. they tend to concentrate those heavy metals which play prominent roles in contemporary enzymic redox processes. The prebiotic formation of similar polymers could, therefore, have provided the starting point for a basic class of biochemical reactions. We suggest that the prebiotic scenario involved chemical and protoenzymic reactions at the sediment-ocean interface in relatively shallow waters and under conditions not much different from those of the recent environment.
J Mol Evol 1975 Dec 29
PMID:On the possible role of organic melanoidin polymers as matrices for prebiotic activity. 0 42

Comparative data on quaternary structure, cooperativity, Bohr effect and regulation by organic phosphates are reviewed for vertebrate hemoglobins. A phylogeny of hemoglobin function in the vertebrates is deduced. It is proposed that from the monomeric hemoglobin of the common ancestor of vertebrates, a deoxy dimer, as seen in the lamprey, could have originated with a single amino acid substitution. The deoxy dimer has a Bohr effect, cooperativity and a reduced oxygen affinity compared to the monomer. One, or two, additional amino acid substitutions could have resulted in the origin of a tetrameric deoxy hemoglobin which dissociated to dimers on oxygenation. Gene duplication, giving incipient alpha and beta genes, probably preceded the origin of a tetrameric oxyhemoglobin. The origin of an organic phosphate binding site on the tetrameric hemoglobin of an early fish required only one, or two, amino acid substitutions. ATP was the first organic phosphate regulator of hemoglobin function. The binding of ATP by hemoglobin may have caused the original elevation in the concentration of ATP in the red blood cells by relieving end product inhibition of ATP synthesis. The switch from regulation of hemoglobin function by ATP to regulation by DPG may have been a consequence of the curtailment of oxidative phosphorylation in the red blood cell. The basic mechanisms by which ATP and DPG concentrations can respond to strss on the oxygen transport system were present before the origin of an organic phosphate binding site on hemoglobin. A switch from ATP regulation to IP5 regulation occurred in the common ancestor of birds.
J Mol Evol 1975 Dec 29
PMID:Hemoglobin function in the vertebrates: an evolutionary model. 0 43

Imidazole catalysis of phenylalanyl transfer from phenylalanine adenylate anhydride to the hydroxyl groups of homopolyribonucleotides was investigated as a chemical model of the biochemical aminoacylation of tRNA. Imidazole catalyzed transfer of phenylalanine to poly(U) increases from pH 6.5 to 7.7 and decreases above pH 7.7. At pH 7.7 approximately 10% of the phenylalanyl residues are transferred to poly(U). At pH 7.1, transfer to poly(U) was five times as great as to poly(A) and transfer to a poly(A) poly(U) double helix was negligible. At pH 7.1 approximately 45 mole percent linkages to poly(U) were monomeric phenylalanine; the remainder of the linkages were peptides of phenylalanine. The number of linkages and their lability to base and neutral hydroxylamine indicates that phenylalanine and its peptides are attached as esters to the 2' hydroxyl groups throughout poly(U) and the 2' (3') hydroxyl groups at the terminus of poly(U). These results do model the contemporary process of aminoacyl transfer to tRNA and continue to suggest that a histidine residue is in the active site of aminoacyl-tRNA-synthetases.
J Mol Evol 1975 Dec 29
PMID:Aminoacyl transfer from an adenylate anhydride to polyribonucleotides. 0 44


J Mol Biol 1975 Dec 15
PMID:The determination of stability constants from small-angle x-ray scattering data and the analysis of pH-dependent macromolecular equilibria. 0 84


J Mol Biol 1975 Dec 25
PMID:Subunit composition, x-ray diffraction, amino acid analysis and oxygen binding behaviour of Panulirus interruptus hemocyanin. 0 85

Aminomalononitrile (HCN trimer) reacts with electrophiles such as aldehydes and acrylonitrile under very mild conditions of temperature and pH to produce intermediates which, after acid hydrolysis, yield amino acids. The following amino acids have been identified and quantitated: glycine, D, L-erythro- and D, L-threo-beta - hydroxyaspartic acids, D, L glutamic acid, and D, L-threonine and allo-threonine. The mechanism of their formation and the possible significance of these reactions in prebiotic syntheses are discussed.
J Mol Evol 1975 Dec 31
PMID:Reactions of aminomalononitrile with electrophiles. 0 86

All Bacillus subtilis R-type strains showing the phenomena of restriction and modification contain an endonuclease that inactivates in vitro the biological activity of a variety of DNAs lacking R-specific modification, such as transfecting SPPI, SPO2 and phi105 DNA, and transforming B. subtilis 168-type DNA. The corresponding DNAs carrying R-specific modification are resistant to the enzyme. The enzyme has been purified approximately 400-fold and is essentially free from contaminating double strand-directed unspecific exo- or endonuclease activity. Only Mg2+ is required as cofactor. The substrate DNAs are cleaved at specific sites. The double-stranded fragments produced from SPP1 DNA (molecular weight 2.5 x 10(7)) have an average molecular weight of about 3 x 10(5).
Mol Gen Genet 1975 Dec 30
PMID:Restriction and modification in B. subtilis. Purification and general properties of a restriction endonuclease from strain R. 0 56


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