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)

Histochemical observations were made of the activities of nucleosidephosphatases splitting ATP, ADP, IDP, and AMP and exopeptidases splitting l-alanine, l-leucine and l-glycyl-proline in the spleen sinuses of man, mouse, rat, hamster, and rabbit. Of the exopeptidases, only glycylprolyl-naphthylamidase could be proved histochemically, and that only in man and rat. Nucleosidephosphatases showed only traces of activity except in the rabbit where there was highly active AMP-ase, the others being moderately active.
Virchows Arch B Cell Pathol Incl Mol Pathol 1979 Dec
PMID:Comments on spleen sinus enzyme equipment. A histochemical study. 4 57

Theoretical conformational analysis of the antibiotic gramicidin A HCO--L-Val--Gly--L-Ala--D-leu--L-Ala--D-Val--L-Val--D-Val--(L-Trp--D-Leu)3--L-Trp--NHCH2CH2OH has been carried out by stagewise computations of a serie of LD penta-decapeptide analogs, which approximated the structure of the natural compound at the final stage. The potential surface of the LD-peptide skeleton of the gramicidin molecule is shown to predetermine the existence of a set of pi4LD--Pi6LD structures. Low-energy helical structures with no hydrogen bonds have also been revealed, which are due to compensational relations between hydrogen bonding and nonbonded energies. Inclusion of D-Val into the amino acid sequence discriminate against alpha-helix, while Trp and Leu residues contribute to a formation of pi4LD and pi6LD helices and to a reduction of energy differences between them. Conformational properties and geometrical parameters of the lowest-energy helical structures of gramicidin provide transport of protones and of all alkali metal ions. A mechanism of cation transportation through the gramicidin trans-membrane channel is discussed.
Mol Biol (Mosk)
PMID:[Conformational state and mechanism of functioning of gramicidin A]. 8 46

When plasmids carrying leucine genes of Bacillus subtilis 168 were isolated from a restriction and modification deficient (r-m-) strain and used for transformation of a restricting strain B. subtilis 168 leu recE4, the number of transformants was greatly reduced. Transformation of rec+ strain (transformation by integration of the donor DNA into the chromosome) with the plasmids was not affected irrespective of whether the recipient carried the r+ or r- phenotype. These results show that the plasmid-mediated transformation is subject to the host controlled restriction and suggest that r-m- strains should be used for construction of recombinant DNA molecules in B. subtilis 168.
Mol Gen Genet 1979 Sep
PMID:Restriction of plasmid-mediated transformation in Bacillus subtilis 168. 11 81

Measurement of the effect of drugs on the in vivo rates of synthesis of rabbit liver organelle bound proteins were measured following individual treatments with the inducers phenobarbital, 3-methylcholanthrene and PCB (a mixture of polychlorinated biphenyls) and the inhibitors, cycloheximide, aflatoxin B1, chloramphenicol and actinomycin D. Following their isolation from a homogenate containing the combined livers of 14C-leucine injected experimental animals and 3H-leucine injected control animals, purified fractions of the following proteins were prepared: microsomal cytochrome b5, cytochrome P-450, NADH-cytochrome b5 reductase, NADPH-cytochrome P-450 reductase and proteolipids, outer mitochondrial membrane cytochrome b5, NADH-cytochrome b5 reductase and proteolipids, inner mitochondrial membrane cytochrome c, NADH dehydrogenase and proteolipids, intermitochondrial membrane cytochrome b5 and circulating serum albumin. The effect of a drug was examined by measuring the 14C/3H ratio of leucine incorporation of each fraction; ratios which differed markedly from a control value of 1 represented actual changes in the relative rates of protein synthesis. Increased rates of synthesis of cytochrome P-450 and its reductase, intermitochondrial membrane cytochrome b5 and all three proteolipid fractions resulted from each inducer treatment. Treatments with 3-methylcholanthrene and PCB also increased the rate of synthesis of cytochrome b5 and its reductase in both the microsome and outer mitochondrial membrane. In addition, the PCB treatment increased the rates of synthesis of cytochrome c and NADH-dehydrogenase. The rates of synthesis of cytochromes, reductases and of circulating serum albumin were inhibited following treatments with cycloheximide, aflatoxin B1 and actinomycin D. Actinomycin D appeared to inhibit the release of newly synthesized albumin into the bloodstream while chloramphenicol treatment appeared to inhibit the incorporation of cytochrome c into the mitochondria. After 20 hours of treatment with inhibitors, the inhibitory effect of actinomycin D and cycloheximide were still apparent while the rates of protein synt;esis in chloramphenicol and aflatoxin B1 treated animals increased to levels above the controls. The incorporation of radioactively labeled leucine into the proteolipids of the microsomal, and the outer and inner mitochondrial membranes were inhibited following the treatment with actinomycin D and stimulated following the treatment with cycloheximide.
Mol Cell Biochem 1979 Dec 14
PMID:Effect of a single dose of inducers and inhibitors on the rate of synthesis of cytochromes and reductases in liver organelles. 11 59

The relative genetic position of the following four mutations of ribosomal protein S5 has been determined: spc-13, a mutation to spectinomycin resistance; stri N421 and strid1023, mutations suppressing dependence on streptomycin and sup0-1, a mutation suppressing partially the temperature-sensitive phenotype of an alanyl-tRNA synthetase mutation. The transduction experiments performed indicate that the spc-13 site is located in the S5 cistron proximal to the strA locus, that sup0-1 maps proximal to the aroE gene and that the striN421 and strid1023 loci are located between these two mutational sites. Proteinchemical analysis of the amino acid replacement in protein S5 of strain N421 (carrying the striN421 allele) has shown that an arginine residue is replaced by leucine which results in the appearance of a trypsin intensitive bond between the tryptic peptides T2 and T16. The same alteration has been previously found by Itoh and Wittmann (1973) in the S5 protein of strain d1023. Determination of the alteration of ribosomal protein S5 of strain 0-1 (sup0-1 allele) revealed that the C-terminal tryptic peptide is altered. It differs from that of the wild-type protein by the lack of five amino acids and the appearance of a C-terminal glycine residue instead of a lysine residue. This change can be explained by the deletion of eleven nucleotides in the S5 cistron of strain 0-1. The recent determination of the primary structure of ribosomal protein S5 (Wittmann-Liebold and Greuer, 1975) allows the ordering of the S5 alterations employed: The order is spc-13-strid1023 (striN421)-sup0-1 with the spc-13 amino acid replacement being located at the NH2-terminal portion of the S5 sequence and the alteration of strain 0-1 at the COOH-terminal end. The proteinchemical results are therefore in full agreement with the genetic data and unambiguously allow the conclusion that the S5 cistron is transcribed counterclock-wise on the Escherichia coli chromosome.
Mol Gen Genet 1975 Dec 30
PMID:Genetic position and amino acid replacements of several mutations in ribosomal protein S5 from Escherichia coli. 12 73

1. The metabolic responses to an oral glucose tolerance test (100 g) and an intravenous insulin provocation test (0-1 i.u./kg) were studied in nine control subjects and nine patients with Huntington's chorea. 2. Plasma glucose responses to these stimuli were identical in both groups. 3. High fasting concentrations of non-esterified fatty acid (NEFA) were recorded in the choreic patients when compared with control subjects. This difference was maintained under hypoglycaemic conditions. However, during hyperglycaemia the differences in NEFA concentrations between the groups was abolished. 4. Total plasma tryptophan concentrations were equal in the two groups. Free plasma tryptophan, however, was markedly reduced in the choreic group, and this appeared to be a result of a disturbed relationship between free tryptophan and NEFA concentrations. The abnormalities in free tryptophan values were sensitive to plasma glucose concentrations, as hyperglycaemic conditions markedly reduced the differences between the choreic and control group. 5. Patients with Huntington's chorea showed reduced fasting plasma concentrations of leucine, isoleucine and valine.
Clin Sci Mol Med 1977 Mar
PMID:Plasma glucose, non-esterified fatty acids and amino acids in Huntington's chorea. 13 25

1. Incorporation of [H3]leucine into the TCA insoluble fraction of rat liver mitochondria incubated in vitro is inhibited by uncouplers of oxidative phosphorylation. The inhibition is not correlated with the activation of mitochondrial ATPase. 2. Dependence of mitochondrial protein synthesis on the transmembrane potential is manifested in a wide range of K+ and Mg++ concentrations in the incubation media. 3. The inhibitory action of uncouplers shows a lag period equal to 5-7 minutes, this lag period however is not observed when the uncoupler is added to puromycin-treated mitochondria. 4. Dependence of mitochondrial protein synthesis on the transmembrane potential, which represents a property characteristic for the inner mitochondrial membrane suggests that mitochondrial ribosomes act in close contact with the mitochondrial membrane system.
Mol Cell Biochem 1977 Feb 04
PMID:A study of dependence of protein synthesis in mitochondria on the transmembrane potential. 14 Mar 2

Sertoli cell-enriched preparations were obtained by sequential enzyme treatment of testes of 18-20 day old rats, and were maintained in culture in a chemically defined medium. The addition of highly purified follicle-stimulating hormone (FSH) to cells immediately after preparation, or after 48 h in culture, elicited an increase in the level of cyclic adenosine 3',5'-monophosphate (cAMP) when incubated in the presence of 3-isobutyl-1-methylxanthine (MIX). Luteinizing hormone (LH) had no effect on the cAMP levels. The cells cultured in the presence of FSH or dibutyryl cAMP for 48 h incorporated more [3H]leucine into trichloroacetic acid (TCA)-insoluble material than did cells cultured in the basal medium. Cycloheximide abolished the amino acid incorporation into protein precipitated by TCA. The data demonstrate that the Sertoli cell is a target cell for FSH action, and indicate that added dibutyryl cAMP can duplicate the enhancement of amino acid incorporation into protein elicited by FSH.
Mol Cell Endocrinol 1975 Jul
PMID:Effects of follicle-stimulating hormone on cultures of Sertoli cell preparations. 16 4

1. A colorimetric method was developed for the direct chemical assay of human carboxypeptidase A (carboxypolypeptidase; EC 3.4.12.2) with angiotensin converting enzyme-like activity in serum or plasma, with the substrate analogue glycyl-L-histidylglycine and the angiotensin converting enzyme substrate angiotensin I (A-I). This method was based on the spectrophototometric determination of histidylglycine and histidyl-leucine, products of the hydrolysis of glycyl-L-histidylglycine and A-I respectively. omicron-Phthalaldehyde reacted with the imidazole moiety of nu-terminal histidyl peptides to produce a yellow chromophore. 2. A large number of inhibitors were tested for their effects on carboxypolpeptidase activity. The hydrolysis of Gly-His-Gly and A-I was inhibited by histidyl-leucine and angiotensin II, both products of the hydrolysis of A-I. Bothrops jararaca venom extract, EDTA, rho-chloromercuribenzoate, 8-hydroxyquinoline and 2,3-dimercaptopropanol, previously reported as converting enzyme inhibitors, also inhibited carboxypolypeptidase activity. 3. Angiotensin converting enzyme activity in the serum of sixty-six adults ranged from 10 to 37 nmol of glycyl-L-histidylglygine hydrolysed in 10 min by 10 mu1 of serum at 37 degrees C and pH 7-25.
Clin Sci Mol Med 1976 May
PMID:The spectrophotometric determination of human serum carboxypolypeptidase with angiotensin converting enzyme-like activity. 17 49

The translational activities of cytoplasmic poly A(+)RNA of normal rat liver and Novikoff hepatoma cells in the wheat germ cell free system were found to be approximately 15-20 times greater than tose of the corresponding nuclear poly A(+) RNA. The translationsl activities were 85 and 62 pmoles 3H-leucine incorporated/micron g cytoglasmic poly A(+) RNA for the liver and tumor respectively and 3-4 pmoles 3H-leucine incoporated/micron g nuclear poly A(+)RNA. Inasmuch as intergity of the '5'-cap' of mRNA is essential for its translational activity, quantitative comparisons were made of its content in these RNA fractions. Of the total 32P incorporated into the tumor cytoplasmic poly A(+) RNA, 0.41% was in the '5'-cap'; in nuclear poly A(+) RNA, the '5'-cap' contained 0.11%. After periodate oxidation and labeling with KB3H4, m7 guanosine, the 5'-terminal nucleoside in both liver and Novikoff hepatoma nuclear poly A(+) RNA contained approximately 20% as much isotope as in the cytoplasmic poly A(+) RNA. These results suggest the lower translational activity of nuclear poly A(+) RNA is partly related to its lower content of the '5'-cap'. Molecular selection of poly A(+) RNA for transport out of the nucleus or further cytoplasmic processing may account for the higher percentage of the '5-cap' and the greater translational activity of the cytoplasmic poly A(+) RNA. During these studies, it was also found that the m7 guanosine of the '5'-cap' was not removed during translation of the mRNA in the wheat germ system; this result suggests that the '5'-cap' may associate with allosteric binding sites of initiation factor(s).
Mol Cell Biochem 1977 Mar 21
PMID:Comparative studies on the '5'-cap' and in vitro translational activity of cytoplasmic and nuclear poly A(+) RNA1. 19 41


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