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)

1. Synthesis of several pepstatin A derivatives was performed with the aim of increasing water solubility without altering the capacity to inhibit the renin-angiotensinogen reaction. 2. Pepstatinyl-arginine-O-methyl ester was studied in vitro and in vivo and compared with pepstatin A and with the arginine salt of pepstatin A. 3. This compound inhibited in vitro the reaction between purified hog renin and the synthetic renin N-acetyl-tetradecapeptide or the natural rat renin substrate. The inhibitory constant was of the same order of magnitude as that of pepstatin A. 4. In renal hypertensive rats, the bolus injection of pepstatinyl-arginine-O-methyl-ester or of the arginine salt of pepstatin decreased blood pressure to the same extent as a bolus injection of Sar1, Ala8-angiotensin II.
Clin Sci Mol Med Suppl 1978 Dec
PMID:Soluble pepstatins: a new approach to blockade in vivo of the renin-angiotensin system. 28 46

A possible minor route of ornithine catabolism in Aspergillus nidulans might begin with the ornithine decarboxylase reaction and end with the succinic semialdehyde dehydrogenase reaction. It is therefore of interest that the putative structural genes for these two enzymes, puA and ssuA, respectively, are tightly linked group II. However, this linkage is unlikely to have regulatory significance because ileA, the structural gene for threonine dehydratase, separates them. The gene order in this region is ssuA-ileA-puA-mauB-anB. (mauB- mutations result in loss of monoamine oxidase whilst anB- mutations lead to aneurin auxotrophy.) 2. An auxotrophy for ornithine or putrescine in A. nidulans occurs in double mutants lacking arginase and blocked before ornithine in the arginine biosynthetic pathway. Some residual ornithine synthesis in such double mutants can be catalysed by ornithine delta-transaminase, especially if it is synthesised constitutively.
Mol Gen Genet 1977 Feb 28
PMID:Some genetical aspects of ornithine metabolism in Aspergillus nidulans. 32 61

Isoacceptor species of certain amino acid-specific transfer ribonucleic acids (tRNAs) were fractionated by gel permeation chromatography using Sephadex G-100. The separation is attributed to the 20% ethanol-1% NaCl solvent and to the characteristics of Sephadex. Isoacceptor tRNAs specific for cysteine, arginine, phenylalanine, and histidine were recovered from commercial tRNA of yeast by this method. Highly purified cysteine-specific tRNA, obtained by a method which would not be expected to separate isoacceptor molecules when fractionated by this procedure, was shown to contain two cysteine isoacceptor tRNAs.
Mol Cell Biochem 1977 Mar 21
PMID:Separation of isoacceptor cysteine transfer ribonucleic acids of bakers' yeasts. 32 92

The isolation of a new type of gamma transducing phage carrying the bipolar argECBH operon of E. coli K12 is described. The argECBH segment is inserted in the phage in a direction which is opposite from that of previously isolated argECBH-carrying phages. A colE1 argECBH plasmid has been constructed. DNA fragments resulting from digestion of these genetic elements with Eco RI and Hind III restriction enzymes have been characterized by agarose gel electrophoresis and electron microscopy, including hetero-duplex analysis. Two fragments are of special significance for studies on the control of arginine synthesis, one of length 9.8 kilobases carrying the whole argECBH region, the other of length 2 kilobases carrying most or all of the control region between argE and argC.
Mol Gen Genet 1977 Mar 07
PMID:Studies on the bipolar argECBH operon of E. coli: characterization of restriction endonuclease fragments obtained from gammadargECBH transducing phages and a ColE1 argECBH plasmid. 32 64

Different Escherichia coli mutants auxotrophic for polyamines were studied in order to investigate the relationships among polypeptide synthesis in cell-free systems, ribosomal distribution profiles and endogenous polyamine pools. The in vitro protein synthetic activity and the polyribosomal content were reduced in extracts from putrescine-starved cells of the double mutans MA 255 and MA 261, but not in the arginine-conditional auxotroph DK 6. Putrescine addition to the cultures of all these strains previously starved for polyamines, provoked a shift towards monomers in the equilibrium involving ribosomal particles. Concomitant changes in the intracellular levels of polyamines were observed: putrescine and spermidine increased markedly, and cadaverine disappeared.
Mol Cell Biochem 1977 Jul 05
PMID:Polyamines and protein synthesis: studies in various polyamine-requiring mutants of Escherichia coli. 32 22

The cell-free transcription of the argF and argI genes of the arginine biosynthetic regions is described using an S-30 system capable of coupled in vitro transcription-translation. Template DNA isolated from two independently isolated arginine transducing phages was used in this work. Steady state mRNA synthesis was observed which was attributed to RNAase degradation. Regulation of argF mRNA synthesis, directed by the argF gene carried on the specialized transducing phage phi80dargF is effected to the extent of at least 95% by the arginine holorepressor at the transcriptional stage and at least 80% of the regulation of the expression of the argI gene is mediated at the transcriptional stage. Evidence is presented which indicates that the arginine holorepressor prevents RNA polymerase from binding to the arginine promoter and suggests that the operator and promoter sites may overlap.
Mol Gen Genet 1977 Sep 21
PMID:Transcription of the argF and argI genes of the arginine biosynthetic regulon of Escherichia coli K12, performed in vitro. 33 19

The in vitro synthesis of enzymatically-active ornithine transcarbamylase (OTCase) directed by each of the E. coli K-12 OTCase genes (argF and argI) is described. The E. coli OTCase isoenzyme subunits are not identical, whether synthesized in vivo or in vitro, the argF-coded product being about 5% smaller. The OTCase protomers are enzymatically inactive but associate in vitro to an enzymatically active multimer. The rates of subunit association of argF and argI isoenzymes are considerably different. Utilizing the facile assay protocol presented, the regulation of in vitro OTCase synthesis by the specific holorepressor of the arginine regulon is demonstrated. Calculations based upon data presented indicate that there are about 65 molecules of argR gene product per bacterium, a substantially lower estimate than previously reported.
Mol Gen Genet 1977 Nov 29
PMID:Synthesis of the Escherichia coli K12 isoenzymes of ornithine transcarbamylase, performed in vitro. 34 Sep 22

The use of triplet code words in E. coli, phiX174, MS2, and rabbit globin was examined. A significant deficiency of purines in the third position of four fold degenerate codons was noted, although its significance is not understood. There has been no consistent selection against uracil in pyrimidine restricted codons. For many amino acids the choice between code words appears random, while for arginine, isoleucine, and probably glycine, distinct biases exist which can be explained in terms of tRNA availability.
J Mol Evol 1978 Feb 21
PMID:Pattern and chance in the use of the genetic code. 34 96

In a relA+ strain of E. coli starved separately for each of four required amino acids, the intracellular concentration of polysomes decreases as a function of time in all cases: very rapidly in the absence of arginine or leucine, slowly in the absence of threonine or histidine. In a starved isogenic relA strain, the polysome level is either totally stable or else drops slowly. The decrease in the level, when it occurs, does not significantly affect the polysome size distribution. Models for polysome metabolism in amino acid starved cells are discussed.
Mol Biol Rep 1978 Feb 28
PMID:Differential effect of amino acid starvation on polysome decay in Escherichia coli. 34 54

The formation and repressibility of the arginine biosyntietic enzymes acetylornithine delta-aminotransferase (EC 2.6.1.11), acetylornithine deacetylase (EC 3.5.1.16), ornithine carbamoyltransferase (EC 2.1.3.3), and argininosuccinate lyase (EC 4.3.2.1) were studied in an Escherichia coli W derivative (strain 250-10) that carries (a) a mutant allele of the argR regulatory gene causing a diminished repression-derepression range and (b) a streptomycin resistance mutation. In comparison with the streptomycin-sensitive parent 250, all four enzymes (a) are formed as smaller proportions of the total protein (overall range, 12% to 71%), whether the conditions are repressive (arginine excess) or derepressive (arginine restriction), and (b) show increased repressibility ratios, the carbamoyltransferase giving the largest increase (from 5.7 to 25.0). These effects appear to depend on the concurrent expression of the regulatory-gene and streptomycin resistance mutations, as indicated by analogous experiments with canavanine-resistant mutants of 250-10 that have partial argR- character. The results provide evidence for translational repression in the arginine system, and are interpreted in terms of a functional interaction of a mutant arginine repressor with a mutant S12 ribosomal protein. The locale of translational repression may be near the site of S12, and this mode of regulation may involve initiational selectivity of groupwise recognizable arginine messenger RNA's.
Mol Gen Genet 1978 Jun 14
PMID:Evidence for translational repression of arginine biosynthetic enzymes in Escherichia coli: altered regulation in a streptomycin-resistant mutant. 35 28


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