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)

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

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

A novel spectrin variant carrying a truncated beta-chain and designated Spectrin Tokyo (beta 220/216) is presented. It was associated with elliptocytosis and moderate uncompensated hemolysis. The dimer self-association was reduced. An increase of the alpha I 74-Kd fragment was detected upon partial trypsin digestion. Analysis of cDNA and genomic DNA showed a 1-base deletion in codon 2059 (GCC AGC-->GCA GCT; Ala-Ser-->Ala-Ala) that belongs to exon X of spectrin beta-gene. A missense sequence extended down to (new) codon 2075. Serine 2060, a potential phosphorylation site, was replaced by alanine. The shortened beta-chain failed to undergo phosphorylation in vitro. Spectrin Tokyo shared the same stop codon, overlapping normal codons 2076 and 2077 (CTG AAA), as Spectrin Nice (beta 220/216), which is caused by a dinucleotide insertion in codon 2046 and contains 2076 amino acids. However, for some reason, Spectrin Tokyo had a lower incorporation level into the membrane than Spectrin Nice.
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PMID:A deletional frameshift mutation of the beta-spectrin gene associated with elliptocytosis in spectrin Tokyo (beta 220/216). 139 62

The genetic code, formerly thought to be frozen, is now known to be in a state of evolution. This was first shown in 1979 by Barrell et al. (G. Barrell, A. T. Bankier, and J. Drouin, Nature [London] 282:189-194, 1979), who found that the universal codons AUA (isoleucine) and UGA (stop) coded for methionine and tryptophan, respectively, in human mitochondria. Subsequent studies have shown that UGA codes for tryptophan in Mycoplasma spp. and in all nonplant mitochondria that have been examined. Universal stop codons UAA and UAG code for glutamine in ciliated protozoa (except Euplotes octacarinatus) and in a green alga, Acetabularia. E. octacarinatus uses UAA for stop and UGA for cysteine. Candida species, which are yeasts, use CUG (leucine) for serine. Other departures from the universal code, all in nonplant mitochondria, are CUN (leucine) for threonine (in yeasts), AAA (lysine) for asparagine (in platyhelminths and echinoderms), UAA (stop) for tyrosine (in planaria), and AGR (arginine) for serine (in several animal orders) and for stop (in vertebrates). We propose that the changes are typically preceded by loss of a codon from all coding sequences in an organism or organelle, often as a result of directional mutation pressure, accompanied by loss of the tRNA that translates the codon. The codon reappears later by conversion of another codon and emergence of a tRNA that translates the reappeared codon with a different assignment. Changes in release factors also contribute to these revised assignments. We also discuss the use of UGA (stop) as a selenocysteine codon and the early history of the code.
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PMID:Recent evidence for evolution of the genetic code. 157 11

Glycoprotein D (gD) of herpes simplex virus contains three utilized sites (Asn-X-Ser/Thr) for addition of asparagine-linked carbohydrates (N-CHO). Previously, we used oligonucleotide-directed mutagenesis to alter serine or threonine residues to alanine at each N-CHO addition site. Studies with monoclonal antibodies showed that a mutant protein lacking all three sites (now designated AAA) was structurally altered because of the amino acid change at residue 96 as well as the absence of the N-CHO. In this study, we constructed additional single mutations at site 1 (residues 94 and 96) and found that in most cases, the amino acid change itself adversely affected the conformation of gD. However, changing asparagine 94 to glutamine (Q) at site 1 had the least effect on gD. We constructed a second triple mutant, QAA, which lacked all three N-CHO signals. The antigenic conformation of QAA was similar to that of gD produced in the presence of tunicamycin (TM-gD). However, binding of MAbs to the AAA protein or to single mutants altered at site 1 was reduced compared with TM-gD. Wild-type gD and QAA proteins were equally susceptible to digestion by trypsin or Staphylococcus aureus V8 protease. In contrast, the AAA protein was more sensitive to trypsin but less sensitive to V8, again suggesting conformational alterations of the AAA protein. Despite what appeared to be large changes in structure, each mutant complemented the infectivity of a virus lacking gD (F-gD beta). We conclude that the N-CHO and amino acids at N-CHO site 1 play an important role in forming and/or maintaining gD structure, but none of the N-CHO are required for gD to function in the complementation assay.
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PMID:Absence of asparagine-linked oligosaccharides from glycoprotein D of herpes simplex virus type 1 results in a structurally altered but biologically active protein. 164 38

Recent studies have shown that increases in proteolytic activity are associated with abdominal aortic aneurysms (AAAs). We have studied samples of the dilated aortic wall, taken during corrective surgery for AAAs, in terms of the number, type, and tissue location of connective tissue proteinases and their inhibitors. Five distinct caseinolytic serine proteinases and six gelatinolytic metalloproteinases were resolved by molecular weight by use of sodium dodecyl sulfate-substrate gel electrophoresis. Isoforms of the Mr 92,000 neutrophil gelatinase were identified by immunoprecipitation of biosynthetically labeled organ culture media. About 50% of the total radiolabeled protein secreted by AAA organ cultures was identified as the Mr 30,000 glycoprotein, tissue inhibitor of metalloproteinase (TIMP), by immunoprecipitation. Both TIMP and gelatinase were localized to the vasa vasorum by immunoperoxidase staining. However, interstitial collagenase could not be detected by any method. These results suggest the involvement of the vasa vasorum in the maintenance and possibly the genesis of AAAs.
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PMID:Connective tissue proteinases and inhibitors in abdominal aortic aneurysms. Involvement of the vasa vasorum in the pathogenesis of aortic aneurysms. 193 69

Free amino acid (AA) concentrations in plasma and quadriceps femoris muscle were determined in 19 healthy volunteers and in 16 patients with hepatic cirrhosis and portal hypertension. Nutritional state was impaired as judged by overt muscle wasting (9/16), triceps skinfold thickness less than 70% of normal in 8/14 (57%), and creatinine-height index below 70% in 5/12 (42%). In the plasma of patients the typical amino acid pattern of cirrhosis was to be observed: Elevation of tyrosine and methionine (p less than 0.01), uniform reduction of branched chain amino acids (p less than 0.001) resulting in a decreased molar ratio of BCAA/AAA from 2.85 +/- 0.05 in normal individuals to 1.35 +/- 0.12 in cirrhotics (p less than 0.001). Levels of the gluconeogenic AA glutamine, glutamate, aspartate, alanine, glycine, threonine, serine and lysine were lowered (p less than 0.05). In muscle of cirrhotics, intracellular AA concentrations exhibited a similar pattern with two major exceptions: Tyrosine and phenylalanine were augmented (p less than 0.001). Surprisingly, BCAA levels were altered heterogeneously; those of gluconeogenic BCAA decreased: Valine from 0.34 +/- 0.03 to 0.20 +/- 0.03 mmol/l (p less than 0.001), isoleucine 0.09 +/- 0.01 to 0.05 +/- 0.02 mmol/l. However, the concentration of ketogenic leucine remained unaltered in muscle. Nevertheless, the molar ratio of BCAA/AAA was considerably reduced from 3.70 +/- 0.04 to 0.81 +/- 0.08 (p less than 0.001). Most of the gluconeogenic AA exhibited reduced intramuscular concentrations, but glutamine levels were normal. The pattern of plasma and muscle free AA in hepatic cirrhosis is thus characterized by accumulation of aromatic AA and by depletion of gluconeogenic AA, especially BCAA.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Characteristic pattern of free amino acids in plasma and skeletal muscle in stable hepatic cirrhosis. 231 39

The 15,697-nucleotide sequence of Paracentrotus lividus mitochondrial DNA is reported. This genome codes for 2 rRNAs, 22 tRNAs, and 12 mRNAs which specify 13 subunits of the mitochondrial inner membrane respiratory complexes. The gene arrangement differs from that of other animal species. The two ribosomal genes 16 S and 12 S are separated by a stretch of about 3.3 kilobase pairs which contains the ND1 and ND2 genes and a cluster of 15 tRNA genes. The ND4L coding sequence is not contained in the ND4 mRNA but has its own mRNA which maps between the tRNA(Arg) and the Co II genes. The main noncoding region, located in the tRNA gene cluster, is only 132 nucleotides long, but contains sequences homologous to the mammalian displacement loop. Other short noncoding sequences are interspersed in the genome: they contain a conserved AT consensus which probably has a role in transcription or RNA processing. As regards the mitochondrial genetic code, the codons AGA and AGG specify serine and are recognized by a tRNA with a GCU anticodon, whereas AUA and AAA code for isoleucine and asparagine rather than for methionine and lysine. Except for ND4L which starts with AUC and ATPase 8 which starts with GUG, AUG is used as the initiation codon. In 11 out of 13 cases the genes terminate with the canonical stop codons UAA or UAG. These observations suggest that during invertebrate evolution each lineage developed its own mechanism of mitochondrial DNA replication and transcription and of RNA processing and translation.
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PMID:The complete nucleotide sequence, gene organization, and genetic code of the mitochondrial genome of Paracentrotus lividus. 254 76

The 15,650 base-pair mitochondrial genome of the sea urchin Strongylocentrotus purpuratus has been cloned and sequenced. It exhibits a novel organization that suggests the primacy of post-transcriptional gene regulation. The same 13 polypeptides, two rRNAs and 22 tRNAs are encoded as in other animal mitochondrial DNAs, but are organized with extreme economy; non-coding information between genes is almost completely absent, some stop codons are generated post-transcriptionally and tRNA sequences are interspersed between only a minority of other structural genes. The genome uses a variant genetic code, in which AAA specifies asparagine, ATA isoleucine, TGA tryptophan and AGN serine, and has an unusual pattern of codon bias. The order of genes shows several differences from that of vertebrates. The genes for the large (16 S) ribosomal RNA and for NADH dehydrogenase subunit 4L (ND4L) are in different positions, located respectively between those encoding ND2 and cytochrome oxidase subunit I (COI) and between COI and COII. This organization is conserved amongst at least four regular echinoids diverging by some 225 million years. Most tRNA genes are also in different positions. The only long unassigned sequence in the genome (121 base-pairs) is located within a cluster of 15 tRNA genes. It contains elements resembling some of those found in the displacement (D) loop of vertebrate mtDNAs, notably polypurine/polypyrimidine tracts that may play a role in regulating transcription and the initiation of replication. The separation of the ribosomal RNA genes from each other and from the putative control region imposes special demands on the transcription of the genome.
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PMID:Nucleotide sequence and gene organization of sea urchin mitochondrial DNA. 317 15

The nucleotide sequence of a 3849-bp fragment of starfish mitochondrial genome was determined. The genes for NADH dehydrogenase subunits 3, 4, 5, and COIII, and three kinds of (tRNA(UCNSer), tRNA(His), and tRNA(AGYSer) were identified by comparing with the genes of other animal mitochondria so far elucidated. The gene arrangement of starfish mitochondrial genome was different from those of vertebrate and insect mitochondrial genomes. Comparison of the protein-encoding nucleotide sequences of starfish mitochondria with those of other animal mitochondria suggested a unique genetic code in starfish mitochondrial genome; both AGA and AGG (arginine in the universal code) code for serine, AUA (isoleucine in the universal code but methionine in most mitochondrial systems) for isoleucine, and AAA (lysine) for asparagine. It was also inferred that these AGA and AGG codons are decoded by serine tRNA(AGYSer) originally corresponding to AGC and AGU codons. This situation is similar to the case of Drosophila mitochondrial genome. Variations in the use of AGA and AGG codons were discussed on the basis of the evolution of animals and decoding capacity of various tRNA(AGYSer) species possessing different sizes of the dihydrouridine (D) arm.
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PMID:Unusual genetic codes and a novel gene structure for tRNA(AGYSer) in starfish mitochondrial DNA. 367 36


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