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M Terao

Publications and source records attributed to M Terao.

At least 91 records · Page 5Linked to original sources
PubMed1983

Sequence requirement for transcription in vivo of the human preproenkephalin A gene.

The nucleotide sequence of the 5'-flanking region of the cloned human preproenkephalin A gene, extending to 949 bp upstream of the capping site, has been determined. The preproenkephalin A gene, when joined with an SV40 vector and introduced into COS monkey cells, is efficiently transcribed from its own promoter. To assess the DNA sequence required for promoter function, we have constructed a series of 5'-deletion mutants of a fusion gene that consists of the 949-bp 5'-flanking sequence and capping site of the preproenkephalin A gene and the structural sequence of the herpes simplex virus thymidine kinase gene. The deletions up to 757-172 bp upstream of the capping site exert essentially no effect on the expression of the fusion gene, whereas the deletions up to 145, 111, 81 and 67 bp upstream of the capping site result in a gradual decrease in the transcriptional efficiency. No detectable amount of the fusion gene transcript is produced with the mutants having deletions up to 67, 43 and 28 bp upstream of the capping site. These results indicate that a functional promoter of the preproenkephalin A gene lies between 67 and 171 bp upstream of the capping site. This promoter region corresponds to a highly GC-rich segment with short repeated sequences and palindromes.

Base Composition↗
PubMed1983

Terminal steps in the biosynthesis of herbicidins, nucleoside antibiotics.

The biosynthetic relationship of the herbicidins produced by Streptomyces saganonensis was studied with blocked mutants by means of a bioconversion method using growing and resting cells. It is proposed that the biosynthetic sequence for herbicidins is; herbicidin G----herbicidin F----herbicidin A. Both herbicidins A and F were converted to herbicidin B by non-enzymatic reactions. Herbicidin G was also converted to herbicidin C non-enzymatically.

Anti-Bacterial Agents↗
PubMed1983

Milbemycins, a new family of macrolide antibiotics. Fermentation, isolation and physico-chemical properties of milbemycins D, E, F, G, and H.

Strain Au-3, a mutant of Streptomyces hygroscopicus subsp. aureolacrimosus, obtained with ultraviolet irradiation, was a high-yield strain of milbemycins D, E, F, G and H. Fermentation studies on the strains were conducted in shake flasks and 30-liter jar fermentors. Isolation of the metabolites was performed by adsorption on resinous adsorbent followed by elution with aqueous MeOH and separated by silica gel column chromatography. Milbemycin D was obtained as colorless needles after recrystallization and milbemycins E, F, G and H were purified to homogeneity by column chromatography. Physico-chemical characterization revealed that milbemycins D, E, F, G and H were new antibiotics possessing the 16-membered macrocyclic lactone with a 6,6-membered spiroketal ring system.

Anti-Bacterial Agents↗
PubMed1983

Milbemycins, a new family of macrolide antibiotics. Fermentation, isolation, physico-chemical properties and bioconversion of milbemycins J and K.

Strain Rf-107, a mutant of Streptomyces hygroscopicus subsp. aureolacrimosus, obtained with ultraviolet irradiation, produced two new macrolide antibiotics, milbemycins J and K without production of any of the other milbemycins described in the previous paper. Fermentation studies on the strain were conducted in shake flasks and 30-liter jar fermentors. Isolation of the antibiotics was performed by adsorption on resinous adsorbent followed by elution with aqueous MeOH. Purification of milbemycins J and K was completed with Lobar Si 60 column chromatography to give colorless crystals. Physico-chemical data, such as UV, IR and NMR spectra are described. Milbemycins J and K were readily converted by the intact cells of the parent strain to milbemycins alpha 1 and alpha 3, respectively. Physico-chemical characterization and the bioconversion studies revealed that milbemycins J and K were new antibiotics having the 16-membered macrocyclic lactone with a 6,6-membered spiroketal ring system.

Anti-Bacterial Agents↗
PubMed1983

Milbemycins, a new family of macrolide antibiotics. Studies on the biosynthesis of milbemycins alpha 2, alpha 4 and D using 13C labeled precursors.

The biosynthetic origins of the carbon skeleton of milbemycins alpha 2, alpha 4 and D were studied. 13C Labeled antibiotics, milbemycins alpha 2, alpha 4 and D, were isolated from the culture broth of Streptomyces hygroscopicus subsp. aureolacrimosus strain Au-3 after feeding [1-13C]acetate, [1-13C]-propionate, [3-13C]propionate, [1-13C]isobutyrate, DL-[2-13C]valine and L-[methyl-13C]methionine, and 13C NMR spectra of the antibiotics thus obtained were measured. It was revealed that the carbon skeleton, except for carbon 25, of milbemycins alpha 2, alpha 4 and D are derived from seven acetate units and five propionate units. It was also shown that the methyl, ethyl and isopropyl groups at carbon 25 in milbemycins alpha 2, alpha 4 and D are derived from acetate, propionate and isobutyrate or DL-valine, respectively, and the methyl carbon of the methoxy group at carbon 5 in milbemycins alpha 2 and alpha 4 was enriched by L-[methyl-13C]methionine.

Acetates↗
PubMed1981

[Labeling reactions of L-lysine and poly-L-lysine with 57Co and their distribution in normal and Ehrlich ascites tumor-bearing mice (author's transl)].

The labeling reactions of L-lysine and poly-L-lysine (average of molecular weight: 3400 (I), 15000 (II), 25000 (III) and 87000 (IV) with 57Co2+ ions and the tumor and organ distributions of their complexes were examined. L-Lysine and poly-L-lysine with 57Co2+ ions were incubated for 20 hrs at 30 degrees C in the solution of pH 9.0 and 50 v/v% ethanol solution of pH 10.5, respectively. L-Lysine and poly-L-Lysine were labeled with 57C02+ ions in radiochemical yields of over 95 and 60-70%, respectively. The radioactive polypeptides were separated from unreacted 57Co2+ ions in the range of pH 8.0 to 8.5 by means of gel filtration on Sephadex G-25 M column (1.5 X 5.0 cm). The radioactive complexes were injected intravenously in mice. L-Lysine complex was excreted rapidly from tumour tissue and various organs. The localization of poly-L-lysine complexes in tumor was higher 3 to 5 times than that of L-lysine complex at 20 hrs after injection. The localization in tumor increased in the order of L-lysine-less than II-less than I-complex. II-Complex was excreted scarcely from tumor. 57Co-poly-L-lysine complexes revealed remarkably high localization in liver and spleen. THe localization in tumor of those complexes seemed to be related to the molecular weight and the positive charge of lysine.

Animals↗
PubMed1980

New Selective Growth Inhibitors of Sphaerotilus natans, Anslimins A and B.

Selective growth inhibitors of Sphaerotilus natans were detected in the culture broths of several strains of Streptomyces. Anslimins A and B were isolated from the culture broth of Streptomyces oganonensis by adsorption on resinous adsorbent followed by elution with 50% aqueous acetone. The A and B components were then separated by cellulose powder chromatography. Physicochemical parameters of anslimins A and B revealed that these compounds are new peptide-containing structures. Anslimins A and B inhibited growth of S. natans at 0.78 and 0.39 mug/ml, respectively, but showed no activity against any of the other test microorganisms at 100 to 200 mg/ml. The anslimins had no harmful effect on guppies at a concentration of 100 mg/liter.

Journal Article↗
PubMed1980

Effect of verapamil on 45Ca uptake by synaptosomes.

The effect of verapamil on K-stimulated 45Ca uptake (the difference between uptake in 60 mM-Ko medium and 5 mM-Ko medium) was studied using a synaptosomal fraction from rat brain. Verapamil inhibited K-stimulated 45Ca uptake, but not 45Ca uptake in 5 mM-Ko media (1 mM- and 0.1 mM-Cao media). The concentrations of verapamil inducing 50% inhibition of K-stimulated 45Ca uptake (ID50) in 1 mM- and 0.1 mM-Cao media were not significantly different, being about 10(-4) M and 2 X 10(-4) M, respectively. Like verapamil, Mn++ inhibited only K-stimulated 45Ca uptake, but its ID50 values in 1 mM- and 0.1 mM-Cao media were about 1.7 mM and 0.2 mM, respectively. It is considered from these findings that both verapamil and Mn++ specifically inhibit K-stimulated 45Ca uptake, but the modalities of their inhibitory effects on K-stimulated 45Ca uptake are different.

Animals↗
PubMed1980

Milbemycins, a new family of macrolide antibiotics: fermentation, isolation and physico-chemical properties.

A search for novel insecticides has yielded the milbemycins, a new family of macrolide antibiotics with insecticidal and acaricidal activity. They are produced in submerged cultures of Streptomyces hygroscopicus subsp. aureolacrimosus. Fermentation studies on the strain were conducted in shaken flasks and 30-liter jar fermentors. From the culture broth 13 milbemycins were purified to homogeneity by column and thin-layer chromatography on silica gel and alumina. Physico-chemical data, such as mass spectra, UV and IR absorption spectra, optical rotations and melting points of the milbemycins are described.

Anti-Bacterial Agents↗
PubMed1979

Involvement of long-chain acyl coenzyme A for lipid synthesis in repression of acetyl-coenzyme A carboxylase in Candida lipolytica.

Mutant strains of Candida lipolytica defective in acyl-CoA synthetase II [acid:CoA ligase (AMP-forming), EC 6.2.1.3] have been isolated. The mutants fail to grow on fatty acid as a sole carbon source but are capable of incorporating exogenous fatty acid into cellular lipids. This observation, together with our previous finding that mutant strains defective in acyl-CoA synthetase I cannot incorporate exogenous fatty acid into cellular lipids but are able to degrade fatty acid via beta-oxidation, indicates the presence of two functionally distinct long-chain acyl-CoA pools in the cell--i.e., one for lipid synthesis and the other for beta-oxidation. Unlike the wild-type and the revertant strains as well as the mutants lacking acyl-CoA synthetase II, the mutants defective in acyl-CoA synthetase I do not exhibit the repression of acetyl-CoA carboxylase [acetyl-CoA:carbon-dioxide ligase (ADP-forming), EC 6.4.1.2] by exogenous fatty acid. Measurement of the two long-chain acyl-CoA pools with the aid of appropriate mutant strains has indicated that the long-chain acyl-CoA to be utilized for lipid synthesis, but not that to be degraded via beta-oxidation, is involved in the repression of acetyl-CoA carboxylase.

Acetyl-CoA Carboxylase↗
PubMed1979

Herbicidins C and E, two new necleoside antibiotics.

Streptomyces saganonensis No. 4075 used for production of herbicidins A and B has also produced other two antibiotics, herbicidins C and E in submerged culture. Isolation of the antibiotics was performed by adsorption on resinous adsorbent followed by elution with aqueous MeOH and completed by silica-gel chromatography. Physico-chemical characteriation revealed that herbicidins C and E are new nucleoside antibiotics having an adenine moiety in their structures. Herbicidins C and E indicated inhibitory activity against germination of chinese cabbage at 12.5 micrograms/ml and 25 micrograms/ml, respectively, and Anacystis nidulans, a blue green algae, at 100 approximately 200 micrograms/ml.

Anti-Bacterial Agents↗