Search PubMed⌕ Search

Biomedical subjects

I Kawamoto

Publications and source records attributed to I Kawamoto.

At least 55 records · Page 3Linked to original sources

A new antibiotic echinosporin (XK-213) - producing organism, isolation and characterization.

Streptomyces echinosporus MK-213 produces a noval antibiotic echinosporin (XK-213). Isolation of echinosporin was performed by absorption on activated carbon under acidic conditions and then eluted by aqueous acetone. The compound crystallized from methanol is a water soluble white solid composed of C10H9NO5. Echinosporin exhibits weak antibacterial activities against Gram-positive and -negative microorganisms and its shows antitumor activity.

Animals↗

Prothracarcin, a novel antitumor antibiotic.

A novel antibiotic, prothracarcin was isolated from the culture broth of Streptomyces umbrosus subsp. raffinophilus DO-62. The antibiotic has the molecular formula of C14H14N2O and belongs to the pyrrolo [1,4]benzodiazepine antibiotics. Its structure has been elucidated by mass and NMR spectra. It is active against Gram-positive and Gram-negative bacteria and experimental murine tumor sarcoma 180 and leukemia P388.

Animals↗

Cell wall composition of Micromonospora olivoasterospora, Micromonospora sagamiensis, and related organisms.

Cell walls of 19 Micromonospora species were analyzed for their components. All the cell walls had xylose and arabinose, but the presence of glucose, galactose, mannose, or rhamnose depended on the strain. Amino acids present in the walls consisted of glycine, glutamic acid, diaminopimelic acid, and alanine, in a molar ratio of approximately 1:1:1:0.6--0.8. 3-Hydroxydiaminopimelic acid, together with meso-diaminopimelic acid, was found in many species and was isolated from Micromonospora olivoasterospora to compare the color constant in an amino acid analyzer with that of meso-diaminopimelic acid. The cell walls of Micromonospora sagamiensis and M. olivoasterospora contained only D-alanine and not L-alanine. All species tested except Micromonospora globosa contained glycolate in an almost equimolar ratio to diaminopimelic acid in their cell walls. Among 45 strains of 12 genera examined, Actinoplanes, Ampullariella, Amorphosporangium, and Dactylosporangium species had a significant amount of glycolate in the whole cells. Based on these results, the primary structure of the peptidoglycan of Micromonospora is discussed.

Actinomycetales↗

Fortimicin A production by Micromonospora olivoasterospora in a chemically defined medium.

A chemically defined medium was devised in order to study the requirements for fortimicin A production by Micromonospora olivoasterospora KY 11515. Soluble starch was the best carbon source; NH4Cl and NH4NO3 were suitable nitrogen sources both for the growth and fortimicin production. Amino acids such as L-asparagine, L-aspartic acid and L-glutamic acid showed some stimulatory effects on both growth and antibiotic production of M. olivoasterospora while L-serine stimulated only antibiotic production and L-citrulline only the growth. K2HPO4, MgSO4.7H2O and CaCO3 were essential especially for the antibiotic production. The most important finding was that vitamin B12, cobalt and nickel showed marked stimulatory effects on fortimicin A production.

Amino Acids↗

Fortimicins A and B, new aminoglycoside antibiotics. I. Producing organism, fermentation and biological properties of fortimicins.

A culture of Micromonospora species MK-70 was found to produce two new antibiotics, fortimicins A and B. Antibacterial and paper chromatographic data on an eluate from IRC-50 treatment of fermentation beers indicated that fortimicins A and B are new antibiotics with broad-spectrum, basic and water-soluble properties. Fortimicin A exhibited potent, unique, broad-spectrum antibacterial activity against Gram-positive and negative bacteria both in vitro and in vivo, while fortimicin B was only weakly active.

Aminoglycosides↗

Fortimicins A and B, new aminoglycoside antibiotics. II. Isolation, physico-chemical and chromatographic properties.

The aminoglycoside antibiotics fortimicins A and B produced by a naturally occurring strain Micromonospora sp. MK-70 were isolated from its fermentation beer. Fortimicins A and B were isolated as water-soluble, basic, white amorphous powders having molecular formula C17H35N5O6 and C15H32N4O5, respectively. Acid hydrolysis of fortimicin A indicated that it has one mole of glycine in its molecule while fortimicin B has not. Paper chromatography, silica-gel and carbon thin-layer chromatography revealed that fortimicins A and B are novel aminoglycoside antibiotics.

Aminoglycosides↗

New antibiotic XK-62-2 (sagamicin). II Taxonomy of the producing organism, fermentative production and characterization of sagamicin.

Cultures of Micromonospora species, strains MK 65 and MK 62, were found to produce a new antibiotic XK-62-2 (Sagamicin). Antibacterial and paperchromatographic data on an eluate from IRC50 treatment of fermentation beers indicated that XK62-2 is a new antibiotic with broad spectrum, basic, and water-soluble properties, probably closely related to the gentamicin C group of antibiotics.

Anti-Bacterial Agents↗

A new antibiotic victomycin (XK 49-1-B-2). II. Isolation, purification and physicochemical and biological properties.

A new antibiotic, victomycin, is active against a variety of Gram-positive and Gram-negative bacteria, and also has in vivo activity against solid Sarcoma 180 and Ehrlich ascites carcinoma. It belongs to the phleomycin-bleomycin group of antibiotics and has been differentiated from all known phleomycins and bleomycins by its physicochemical properties and thin-layer chromatograms.

Animals↗

Platomycins A and B I Taxonomy of the producing strain and production, isolation and biological properties of platomycins.

Two new antibiotics, platomycins A and B, belonging to the phleomycin-bleomycin family, were isolated from the culture filtrate of Streptosporangium sp. MK-78. This strain has been identified as a new variety of Streptosporangium violaceochromogenes. Both platomycins A and B are active against a variety of Gram-positive and Gram-negative bacteria, and also inhibit solid Sarcoma 180 and Ehrlich ascites carcinoma.

Actinomycetales↗

Platomycins A and B II. Physicochemical properties.

Platomycins A and B, two new antibacterial and antitumor antibiotics were found to belong to the phleomycin-bleomycin family, being closely related to bleomycins B. The two ahtibiotics have been differentiated from all of the reported phleomycins and bleomycins.

Antibiotics, Antineoplastic↗