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K Higo

Publications and source records attributed to K Higo.

67 records · Page 4Linked to original sources
PubMed1979

Isolation and characterization of twenty-three ribosomal proteins from large subunits of yeast.

The proteins of large ribosomal subunits from Saccharomyces cerevisiae were separated into 25 fractions by chromatography on columns of carboxymethylcellulose (CMC). Twenty-three proteins were then purified from the 12 CMC fractions by filtration through Sephadex G-75, Sephadex G-100, and Sephacryl S-200, and/or by phosphocellulose column chromatography. The isolated proteins are YP 1, YP 2, YP 9, YP 11, YP 13', YP 16, YP 18, YP 26, YP 39, YP 41, YP 42, YP 42', YP 44, YP 45, YP 47', YP 52a, YP 53, YP 55, YP 59, YP 62, YP 68, YP A1, and YP A2. The molecular weight and amino acid composition of these proteins are presented.

Amino Acids↗
PubMed1979

Isolation and characterization of fourteen ribosomal proteins from small subunits of yeast.

A method for preparation of a large amount of ribosomal subunits from Saccharomyces cerevisiae by a Ti-15 zonal rotor is described. The proteins of the small subunits (ca. 50 000 A260 units) were separated into 22 fractions by chromatography on carboxymethylcellulose columns. Fourteen proteins were then purified from the ten chromatographic fractions by filtration through Sephadex G-100 or Sephacryl S--200. The isolated proteins are YP 6, YP 7, YP 9, YP 12, YP 14', YP 14'', YP 28, YP 38, YP 45, YP 50, YP 52, YP 58, YP 63, and YP 70. The molecular weight and amino acid compositions of these proteins are presented.

Amino Acids↗
PubMed1977

The rates of evolution in some ribosomal components.

The rate of nucleotide substitution (k(nuc)) of 5s RNA was estimated to be (1.8 +/- 0.5) x 10(-10) per site per year by comparing the nucleotide sequences of human and Xenopus 5s RNA and using the geological time elapsed since the separation of mammals and amphibians. Similarly, k(nuc) of 5.8s rRNA was calculated to be 0.93 10(-1u) per site per year from the sequences of rat hepatoma cells and Saccbaromyces cerevisiae. For the comparison of these data with the amino acid substitution rate of known proteins, the k(nuc) values of 5s rRNA and 5.8s rRNA were converted to the rate of amino acid substitution (k(aa')). The k(aa') values in pauling units were 0.4 and 2 0.3, respectively. The average k(aa) of ribosomal proteins was also estimated to be 0.2 0.3 pauling from the N-terminal amino acid sequences of seventeen 30s ribosomal proteins of Bacillus stearothermopbilus and Eschericbia coli. Thus, the evolutionary rates of these ribosomal components studied here are similar to each other; they considerably slower than that of the known cellular proteins. Most, if not all, of the replacements in ribosomal proteins occurred between amino acids of a chemically similar nature.

Animals↗
PubMed1975

Ribosomal proteins from streptomycin-resistant and dependent mutants, and revertants from streptomycin-dependence to independence in Bacillus subtilis.

Streptomycin-resistant and dependent mutants were isolated from Bacillus subtilis ATCC 6633. Ribosomal proteins were analysed from six such mutants with chromatography on carboxymethyl cellulose or phosphocellulose columns. An altered specific 30s ribosomal protein, 30B, could be detected in all of these mutants. Streptomycin-independent revertants were isolated from a streptomycin-dependent strain. Some of them had an altered 30s ribosomal protein, 30A, and some others had an altered 30C protein. It was shown that from the data of partial N-terminal amino acid sequences together with amino acid compositions and mobilities on two-dimensional gel electrophoresis of these proteins that 30A, 30B, and 30C proteins were homologous with S5, S12 and S4 of E. coli 30s ribosomal proteins, respectively.

Amino Acid Sequence↗
PubMed1973

Functional correspondence between 30S ribosomal proteins of Escherichia coli and Bacillus stearothermophilus.

30S ribosomal proteins from Bacillus stearothermophilus (B. proteins) have been fractionated and characterized with respect to their ability to replace various E. coli 30S proteins (E. proteins) in the E. coli 30S ribosome reconstitution system. The functional counterparts of all the E. proteins, except S1, S6, S9, and S13, have been tested. In all cases, B. proteins can substitute for E. proteins. Several purified B. proteins are chemically different from their functionally homologous E. proteins. Five B. proteins are immunochemically related to E. proteins; this set includes two proteins that could not be tested in the reconstitution system (S9 and S13). Thus most, if not all, of the E. proteins have functionally equivalent counterparts among B. proteins, even though properties of the two ribosomes are different in several respects. These results suggest that the fundamental structural organization of ribosomes may be the same throughout prokaryotic organisms.

Antigens, Bacterial↗
PubMed1971

Role of 5S RNA in the functions of 50S ribosomal subunits.

50S ribosomal subunits from Bacillus stearothermophilus can be reconstituted from their dissociated components, namely a 5S RNA-free protein fraction, a 5S RNA-free 23S ribosomal RNA fraction, and purified 5S RNA. The biological activity of reconstituted particles in polypeptide synthesis is dependent on the presence of 5S RNA. In the absence of 5S RNA, particles are produced that have greatly reduced activity in (a) polypeptide synthesis directed by synthetic, as well as natural, messenger RNA, (b) peptidyl transferase assay, (c) [(3)H]UAA binding dependent on peptide chain termination factor R1, (d) G factor-dependent [(3)H]GTP binding, and (e) codon-directed tRNA binding assayed in the presence of 30S subunits. Thus, 5S RNA is an essential 50S ribosomal component.

Bacillus↗
PubMedDate not supplied

Modulation of oligosaccharide structure of a pro-urokinase derivative (pro-UK delta GS1) by changing culture conditions of a lymphoblastoid cell line Namalwa KJM-1 adapted to serum-free medium.

Pro-UK delta GS1 was designed as a long-life and thrombin-resistant derivative of pro-urokinase (pro-UK) by deleting the growth factor domain of pro-UK and introducing a glycosylation site near the thrombin cleaving site for thrombin-resistance using site-directed mutagenesis. An expression plasmid for pro-UKDGS1, pIH1UK delta GS1SEd1-5 was constructed and introduced into Namalwa KJM-1, a lymphoblastoid cell line adapted to serum-free medium, and cells resistant to G418 and Methotrexate (MTX) were obtained. Amongst them, the highest pro-UK delta GS1 producer (resistant to 200 nM of MTX), clone 2-9, was selected and used for further studies. Under the conventional conditions, i.e. at 37 degrees C in serum-free ITPSGF medium (based on RPMI-1640 medium), the oligosaccharide structure of pro-UK delta GS1 produced by clone 2-9 mainly consisted of fucose (Fuc)-containing biantennary complex-type oligosaccharide. Addition of dexamethasone (Dex), changed the carbohydrate contents in the media, and a shift down of incubation temperature caused a change in oligosaccharide structure of pro-UK delta GS1 from mainly Fuc-containing biantennary to mainly Fuc-containing tri- and tetraantennary complex-type oligosaccharide. The modulated pro-UK delta GS1 showed superior in vivo activity for a canine femoral thrombosis formed by inserting a copper-coil.

Amino Acid Sequence↗
PubMedDate not supplied

The novel thromboxane A2 receptor antagonist KW-3635 reduces infarct size in a canine model of coronary occlusion and reperfusion.

The effect of KW-3635, a novel thromboxane A2 receptor antagonist, on infarct size was examined in anesthetized dogs subjected to 1.5 hr of occlusion of the left anterior descending coronary artery followed by 4.5 hr of reperfusion. KW-3635 (1 mg/kg, i.v.) was administered 1 hr before reperfusion and continuously infused (1 mg/kg/hr, i.v.) throughout the experiment. KW-3635 significantly (p < 0.001) reduced the infarct size (30.5% in the KW-3635-treated group as compared with 58.7% in the vehicle-treated group). KW-3635 almost completely inhibited platelet aggregation (ex vivo) induced by epinephrine (10 microM) + U-46619 (1 microM). KW-3635 attenuated the loss of creatine phosphokinase activity from the ischemic myocardium. Histopathological examination revealed that KW-3635 prevented neutrophil accumulation into the ischemic myocardium, ameliorated eosinophilic changes and inhibited contraction band formation in the ischemic myocardium. These results indicate that KW-3635 has a cardioprotective activity and suggest that the inhibition of activation or accumulation of neutrophils is involved in the cardioprotection following thromboxane A2 receptor blockade.

Animals↗