Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0162871 (abdominal aortic aneurysm)
 8,664 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The lysine tRNA released from the 70S RNA of avian myeloblastosis virus was separated by reversed-phase chromatography. All of the AAG-coding lysine tRNA's were present in the 70S-associated fraction; however, the AAA-coding lysine tRNA could not be detected. Chromatography of the lysine tRNA released at various temperatures did not show any preferential release of one AAG-coding species over another.
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PMID:Lysine tRNA's associated with avian myeloblastosis virus 70S RNA. 18 25

Four purified tRNALys species from 13-day-old chick embryo muscle have been characterized with respect to the following properties: qualitative oligoribonucleotide composition (polyacrylamide gel electrophoresis after RNase T1 digestion), anticodon response towards AAG and AAA (equilibrium dialysis and polylysine synthesis), strength of the aminoacyl bond (de-esterification kinetics), sedimentation coefficient, and temperature-dependent double helix-to-coil transition. The results confirm the existence of four molecularly independent lysine-specific tRNA's in this eukaryotic system.
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PMID:Comparative characterization of four purified lysine-specific transfer ribonucleic acids from chicken embryos. 40 37

Pseudomonas aeruginosa tRNA was treated with iodine, CNBr and N-ethylmaleimide, three thionucleotide-specific reagents. Reaction with iodine resulted in extensive loss of acceptor activity by lysine tRNA, glutamic acid tRNA, glutamine tRNA, serine tRNA and tyrosine tRNA. CNBr treatment resulted in high loss of acceptor ability by lysine tRNA, glutamic acid tRNA and glutamine tRNA. Only the acceptor ability of tyrosine tRNA was inhibited up to 66% by N-ethylmaleimide treatment, a reagent specific for 4-thiouridine. By the combined use of benzoylated DEAE-cellulose and DEAE-Sephadex columns, lysine tRNA of Ps. aeruginosa was resolved into two isoaccepting species, a major, tRNA Lys1 and a minor, tRNALys1. Co-chromatography of 14C-labelled tRNALys1 and 3H-labelled tRNALys2 on benzoylated DEAE-cellulose at pH 4.5 gave two distinct, non-superimposable profiles for the two activity peaks, suggesting that they were separate species. The acceptor activity of these two species was inhibited by about 95% by iodine and CNBr. Both the species showed equal response to codons AAA and AAG and also for poly(A) and poly(A1,G1) suggesting that the anticodon of these species was UUU. Chemical modification of these two species by iodine did not inhibit the coding response. The two species of lysine of Ps. aeruginosa are truly redundant in that they are indistinguishable either by chemical modification or by their coding response.
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PMID:Isoaccepting lysine transfer ribonucleic acid species of Pseudomonas aeruginosa. 81 94

In an attempt to explore how specific features of the substrate's primary structure may affect the activity of rabbit muscle acylaminoacyl-peptide hydrolase (EC 3.4.19.1), a number of acetylated peptides containing specific amino acid replacements in specific positions were prepared and compared as substrates for the hydrolase. The principal variants were D-Ala, Pro, and positive charges (His, Arg, Lys); in addition, the effect of the length of the peptide was also investigated in a less systematic manner. The substrates were either prepared by direct acetylation of peptides, by extension of the N-terminus with acetylamino acids or acetylpeptides, activated as N-hydroxysuccinimide esters, or by isolation of the N-terminal peptides from naturally occurring acetylated proteins. It was found that D-Ala on either side of the bond to be cleaved (positions 1 and 2) completely inhibited the enzymatic activity, whereas acetylated peptides with D-Ala in positions 3 or 4 were as good substrates as those containing L-Ala. Peptides with Pro in positions 2 were also inactive, and most of the peptides with Pro in the third position were very poor substrates; only the peptide Ac-AAP gave reasonably high activity (30% of Ac-AAA), which was reduced to 1-2% if additional residues were present at the C-terminus (Ac-AAPA, Ac-AAPAA). The presence of a positive charge in positions 2, 3, 4, 5, and 6 gave strong reduction in hydrolase activity varying with the charge's distance from the N-terminus from 0 to 15-20% of the rates obtained with the reference peptides without positive charges.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Specificity determinants of acylaminoacyl-peptide hydrolase. 130 57

The sequential changes in plasma free amino acid concentration were analyzed and compared in burned patients with sepsis (n = 12) and without sepsis (n = 19). After burn injury, phenylalanine, methionine, lysine, and the Phe/Tyr ratio were significantly increased in two groups (P < 0.05-0.01). Threonine, serine, histidine, arginine, proline and BCAA/AAA ratio were significantly decreased in two groups (P < 0.05-0.001). The Phel Tyr ratio in patients with sepsis was much higher than that in patients without sepsis on postburn days 14 and 21 (P < 0.05), while the BCAA/AAA ratio in patients with sepsis was much lower than that in patients without sepsis on postburn day 14 (P < 0.01). The level of proline in patients with sepsis was much higher than that in patients without sepsis on postburn days 3 and 7 (P < 0.05). It is suggested that these results, in collaboration with other clinical and laboratory findings, may be helpful in foretelling the probable development of sepsis in patients with major burns.
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PMID:[Changes in plasma free amino acid concentration in burned patients with sepsis]. 130 55

Previous genetic analyses indicated that translational frameshifting in the--1 direction occurs within the run of six adenines in the sequence 5'-TTAAAAAACTC-3' at nucleotide positions 305-315 in IS 1, where the two out-of-phase reading frames insA and B'-insB overlap, to produce transposase with a polypeptide segment Leu-Lys-Lys-Leu at residues 84-87. IS 1 mutants with a 1 bp insertion, which encode mutant transposases with an amino acid substitution within the polypeptide segment at residues 84-87, did not efficiently mediate cointegration, except for an IS 1 mutant which encodes a mutant transposase with a Leu-Arg-Lys-Leu segment instead of Leu-Lys-Lys-Leu. An IS 1 mutant with the DNA segment 5'-CTTAAAAACTC-3' at positions 305-315 carrying the termination codon TAA in the B'-insB reading frame could still mediate cointegration, indicating that codon AAA for Lys corresponding to second, third and fourth positions in the run of adenines is the site of frameshifting. The beta-galactosidase activity specified by several IS 1-lacZ fusion plasmids, in which B'-insB is in-frame with lacZ, showed that the region 292-377 is sufficient for frameshifting. The protein produced by frameshifting from the IS 1-lacZ plasmid in fact contained the polypeptide segment Leu-Lys-Lys-Leu encoded by the DNA segment 5'-TTAAAAAACTC-3', indicating that--1 frameshifting does occur within the run of adenines.
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PMID:Identification of the site of translational frameshifting required for production of the transposase encoded by insertion sequence IS 1. 133 29

A patient with bilateral retinoblastoma and subsequent multiple primary osteosarcomas has been described previously. Osteosarcoma cell lines established from this patient were shown to express a shortened RB1 mRNA transcript and no detectable normal Rb protein. We now show that the osteosarcoma cell lines have lost one TP53 allele and contain a mutation in exon 8 codon 286 [GAA to AAA (Glu to Lys)] in the remaining allele. Consequently, the osteosarcoma cell lines have no normal Rb protein and no normal p53 protein. Neither constitutional DNA nor DNA extracted from a retinoblastoma of the left eye of the patient contained the TP53 mutation, suggesting that the TP53 mutation in the osteosarcoma cells may represent a tumor-promoting mutation, which confers a selective growth advantage. If both RB1 and TP53 are involved in the initiation of osteosarcoma, the mechanisms for development of the retinoblastoma and osteosarcoma tumors are different.
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PMID:A TP53 mutation detected in cells established from an osteosarcoma, but not in the retinoblastoma of a patient with bilateral retinoblastoma and multiple primary osteosarcomas. 133 9

In the A alpha-chain gene coding for an abnormal fibrinogen (fibrinogen Marburg) we identified a single base substitution (A-->T) that changes the codon A alpha 461 AAA (Lys) to TAA (Stop). The propositus was found to be homozygous for the mutation, whereas the father and five siblings were heterozygous, and three other siblings contained only the normal sequence. The stop codon at position 461 results in the deletion of the carboxyl-terminal segment A alpha 461-610. Purified fibrinogen Marburg contained an A alpha-chain with a relative molecular weight of approximately 47,000. The FpA release by thrombin was not affected by this deletion, whereas the fibrin polymerization was strongly decreased. The binding of endothelial cells to immobilized fibrinogen Marburg was almost completely abolished compared with normal fibrinogen. Fibrinogen Marburg contained a substantial amount of albumin linked to the fibrinogen molecule by disulfide bonds, and these fibrinogen-albumin complexes were also present in plasma. The plasma fibrinogen concentration of the propositus was measured by three different methods: a functional method (< 0.25 mg/mL), an immunologic method using polyclonal antibodies (0.6 mg/mL), and an immunologic method based on two monoclonal antibodies specific for the amino-terminus and carboxyl-terminus of the A alpha-chain (< 0.05 mg/mL). Using the two immunologic methods, it appeared that only 10% to 15% of the plasma fibrinogen of the heterozygous siblings was abnormal.
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PMID:Fibrinogen Marburg: a homozygous case of dysfibrinogenemia, lacking amino acids A alpha 461-610 (Lys 461 AAA-->stop TAA). 139 54

A single basepair substitution at conserved position -1 in the exon 3a donor splice site of the liver-expressed antithrombin III (AT3) gene was detected by PCR/direct sequencing in a patient with sporadic type 1 ATIII deficiency and recurrent venous thrombosis. The lesion, a heterozygous silent AAG----AAA transition at Lys 176 occurred de novo in the proposita. Ectopic transcript analysis of lymphocyte mRNA demonstrated the presence of an abnormally sized mRNA specific to the patient which was shown by cDNA sequencing to lack exon 3a. Oligonucleotide discriminant hybridization demonstrated the absence of any detectable transcript of normal length derived from the disease allele. These findings demonstrate the utility of ectopic transcript analysis in the characterization of defects of mRNA splicing.
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PMID:De novo splice site mutation in the antithrombin III (AT3) gene causing recurrent venous thrombosis: demonstration of exon skipping by ectopic transcript analysis. 150 75

Synthesis of the gamma-subunit of DNA polymerase III holoenzyme depends on precise and efficient translational frameshifting to the -1 frame at a specific site in the dnaX gene of Escherichia coli. In vitro mutagenesis of this frameshift site demonstrated the importance of an A AAA AAG heptanucleotide sequence, which allows two adjacent tRNAs to retain a stable interaction with mRNA after they slip to the -1 position. The AAG lysine codon present in the 3' half of this heptanucleotide was a key element for highly efficient frameshifting. A tRNA(Lys) with a CUU anticodon, which has a strong affinity for AAG lysine codons, is present in eukaryotic cells but absent in E. coli. Expression in E. coli of a mutant tRNA(Lys) with a CUU anticodon specifically inhibited the frameshifting at the AAG codon, suggesting that the absence of this tRNA in E. coli contributes to the efficiency of the dnaX frameshift.
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PMID:Sequence requirements for efficient translational frameshifting in the Escherichia coli dnaX gene and the role of an unstable interaction between tRNA(Lys) and an AAG lysine codon. 154 45


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