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Two species of the new genus Catellatospora, belonging to the "actinoplanates" group, are described under the names Catellatospora citrea sp. nov. and 'latellatospora ferruginea sp. nov. The organisms of this genus are aerobic and produce nonfragmenting vegetative hyphae and no true aerial mycelium. Short chains of nonmotile spores emerge singly or in tufts from the vegetative hyphae on the surface of agar media. The organisms have meso-diaminopimelic and 3-hydroxydiaminopimelic acids and glycine in the cell walls (a type I1 cell wall); xylose and arabinose (a pattern D whole-cell sugar); and phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannosides but not phosphatidylcholine (a type PII phospholipid pattern). The major menaquinones in C. citrea and C. ferruginea are MK-9 (H4) and MK-10 (HS), respectively. The guanine-plus-cytosine content of the deoxyribonucleic acids ranges from 70.9 to 71.5 mol%. The type strain of type species C. citrea is strain IF0 14495* (6183-ET), and the type strain of C. ferruginea is strain IF0 14496T (6257-CT).Morphology has always been a major criterion for the delimitation of actinomycete genera. On the other hand, extensive studies of their cell components (9, 12-16) have revealed that biochemical markers such as amino acids in cell walls, reducing sugars, phospholipids, and menaquinones are useful and sometimes indispensable for recognition of genera. Indeed, the recently described genera Kitasatosporia (20), Saccharothrix (lo), and Glycomyces (11) have been distinguished from other genera by both morphological and chemotaxonomic characteristics.During an investigation of soil actinomycetes,l two strains were isolated which had a type I1 cell wall (mesodiaminopimelic acid and glycine were present) and a D whole-cell sugar pattern (xylose and arabinose were present) and bore short chains of nonmotile spores on the vegetative hyphae. These chemotaxonomic characters agree with those of the genus Glycomyces and the genera in the actinoplanates group, but the morphology is different from theirs. The combination of cell chemistry and morphology of our isolates differs from those of all previously described genera of the Actinomycetales; thus, we propose to include these strains in a new genus, Catellatospora. Strain I F 0 14495T (6183-E) is designated the type strain of the type species, C. citrea, and strain I F 0 14496T (6257-C) is designated the type strain of an additional new species, C. ferruginea. MATERIALS AND METHODSBacterial strains and culture conditions. Strains 6183-E and 6257-C were isolated by a dilution method from woodland soil samples collected in Itsukaichi-shi Tokyo and Yamanashi, Japan, respectively. These strains were maintained as slant cultures, frozen seeds in 20% glycerol, or lyophilized preparations. For comparative purpose, we used Glycomyces harbinensis NRRL 15337T, Dactylosporangium aurantiacum KCC A-0083T (ATCC 23491T), and D . thailandense KCC A-O084T (ATCC 23490T) (24). (KCC, Culture collection of the Kake...

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Spore suspensions of 15 strains in 15 species of Micromonospora prepared with ultrasonication-technique were tested for resistance to moist heat, acid, alkali, and organic solvents (5 alcohols, 4 ketones and ether). More than 50% spore-survival was found in most organisms heated at 60°C for 20min, but less than 0.5% survived at 80°C. The spore-viability did not change at pH 6 to 8, but decreased beyond this range, and remarkably at acidic pH. A maximum reduction in viability was found with most organic solvents at a concentration of around 80%, and the spores were more resistant to ketone than alcohols and dioxane. Several Streptomyces species were also studied, and their spores were less resistant to heat and organic solvents than those of Micromonospora. WithStreptomyces and Nocardia,Micromonosprahas attracted muchattention as a promising source of various types of antibiotics.1' 2)The organisms of this genus were knownto occur in muchless frequency in soils,3) but in relatively high numbers in aquatic habits such as lake mud and river sediments.4~8) Since the spore-forming actinomycetes were knownto be present mostly as spores in soils as pointed out in Streptomyces,9>~11) the survival of such organisms could be largely influenced by the properties of these spores. The spores of Micromonospora were borne singly on substrate mycelia. Thus, their physiological properties and structures could be different from those of Streptomyces spores which were formed in long chains on aerial mycelia. In fact, electron-microscopic examination revealed that the former was a broad based type of aleuriospore and was different in spore wall structure to some extent from the latter.12~14) However, only a few studies have been made of physiological properties of Micromonospora spores. This study was undertaken to examine some effects of heat and organic solvents on the viability of the spores of Micromonospora spe-cies including M. inositola,15) M. sagami-ensisi6'17) and M. olivoasterospora,18'19) whichwere known as the producer of the antibiotic XK-41, sagamicin and fortimicin, respectively. MATERIALS AND METHODS Organisms and growth. Twenty two strains ofMicromonospora shown in Table I were used in the study.Additionally 3 strains of Streptomyces (S. bambergriseus ATCC13879, S. griseus ATCC10137 and S. pactum NRRL2939) were studied.Each organism was inoculated into 10ml of a seed medium in a 50ml test tube and then incubated for 2 or 3 days on a reciprocating shaker. The seed*medium consisted of 1 % glucose (Nakarai Chemical, Ltd.), 1 % soluble starch (Kanto Chemical Co.), 0.2% beef extract (Kyokuto Seiyaku Co.), 0.2% yeast extract (Daigo Eiyo Chemical Co.), 0.2% polypeptone (Daigo Eiyo Chemical Co.) and 0.1% CaCO3 (Kanto Chemical Co.). The pH value was adjusted to 7.3 before autoclaving. The seed culture was inoculated in a way of cross-hatch streaks on Hickey-Tresner's agar medium(HT), sporulation agar medium (ATCCNo. 5 medium, SP), or glucose-albumin agar medium (Waksman No. 25 medium, GA). To make easy liberation of spores f...

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-Hydroxydiaminopimnelic 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.

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RES-701-1, a novel cyclic peptide endothelin antagonist, was isolated from the culture broth of Streptomyces sp. RE-701. RES-701-1 selectively inhibited the ET-1 binding to type B endothelin receptor (ETB receptor) with an IC50 of 10 nM expressed in CHOcells and blocked the ET-1-induced elevation of intracellular free Ca2+ concentration in ETB receptor-expressing COS-7 cells. Characterization of producing strain, fermentation, isolation, structure, physico-chemical and biological properties of RES-701-1 are described. Endothelins (ETs) are a family of three related peptides, endothelin 1, 2, and 3 (ET-1, ET-2 and ET-3), which have a variety of biological activities in both vascular and non-vascular tissues, including hemodynamic, cardiac, pulmonary and renal effects. Circulating levels of ET-1 have been found to be elevated in some pathophysiological conditions such as systemic hypertension, cardiac ischemia, asthmatic attacks and cyclosporin-induced renal failure. These observations suggest that specific blockage of endothelin actions at receptor level can be potential treatment of disease states caused by elevated levels ofETs1'2*. In our microbial screening for endothelin antagonists using bovine lung membranes, we isolated a novel cyclic peptide RES-701-1 from the fermentation broth of Streptomyces sp. RE-701. RES-701-1 selectively inhibited ET-1 binding to type B endothelin receptor (ETB receptor) expressed in CHOcells and blocked the ET-1-induced elevation of intracellular free Ca2 + concentration in ETBreceptor-expressing COS-7cells. This paper describes the characterization and fermentation of the producing strain and the isolation, physico-chemical properties and biological activities of RES-701-1. Details of the structure determination are described in the succeeding paper3} Materials and Methods Materials (3-[125I]Iodotyrosyl13)endothelin-l was purchased from Amersham Japan. Endothelin-1 (ET-1) was purchased from Peptide Institute, Inc., Osaka, Japan. Bovine lung was obtained from a local slaughterhouse. The humanB type endothelin receptor gene was the generous gift of Dr. Hirose (