Phylogeny and a new species of Polylobatispora.

During surveys conducted on freshwater fungi from Vietnam, a new aquatic anamorphic fungus was isolated from decaying leaves in Vietnam. The fungus produced phialidic, swollen conidiophore and conidiogenous cells with one-celled conidia with four very tiny lobes. Based on its conidial development and other morphological characteristics, we confirmed that this is a novel fungus and described it as P. ambigua sp. nov. Phylogenetic analyses of P. ambigua based on the LSU nrDNA sequences showed that this fungus clusters in a single clade with the two known Polylobatispora spp. with 97% bootstrap value which is sister with Pseudoprobiscisporaceae. The Polylobatispora clade is nested in the Attracrosporales, Sordariomycetes. Furthermore, in this study two known species of Polylobatispora (P. deltoidea and P. quinquecornuta) were also isolated and illustrated.

Trichoderma matsushimae and T. aeroaquaticum: two aero-aquatic species with Pseudaegerita-like propagules.

Four isolates tentatively identified as Pseudaegerita matsushimae on the basis of the morphology of bulbil-like propagules were collected from substrates submerged in water in Thailand and Japan. In culture studies the two Thai isolates were found to produce phialoconidia on conidiogenous cells and phialoconidiophores whose morphology was similar to that of Trichoderma. Phylogenetic analysis based on D1/D2 regions of LSU rDNA sequences showed that the four isolates were nested in Hypocrea/Trichoderma (Hypocreales) while P. corticalis, the type species of Pseudaegerita, belongs to Hyaloscypha (Helotiales). Preliminary analysis by ISTH Web tools based on 5.8S-ITS rDNA and phylogenetic analysis based on rpb2 and tef1-int4 genes showed that the isolates have specific sequences of Trichoderma (anchors 1-5) and belong to the Hamatum clade but they grouped apart from any known species of Trichoderma. The sequences of the tef1-int4 gene, which were amplified from the authentic specimen of P. matsushimae (IMI 266915), also showed that it belongs to the Hamatum clade closely clustering with T. yunnanense but separate from our four isolates. The morphology of P. matsushimae (IMI 266915), especially the sizes of phialides and phialoconidia, were different from T. yunnanense. Thus, we conclude that IMI 266915 and our isolates are to be assigned to two different species in the Hamatum clade of Trichoderma, although both species have similar morphology of bulbils and phialoconidia. Morphology and molecular data revealed that P. matsushimae should be assigned to the genus Trichoderma as T. matsushimae and the Thai and Japanese isolates are placed in T. aeroaquaticum sp. nov. This finding supports the interpretation that aero-aquatic fungi have evolved from terrestrial fungi. We assume that these fungi probably were derived from typically soil-inhabiting species of Trichoderma; an adaptation to aquatic environments is shown by formation of bulbil-like propagules floating on water.

Antibacterial discovery in actinomycetes strains with mutations in RNA polymerase or ribosomal protein S12.

We show that selection of drug-resistant bacterial mutants allows the discovery of antibacterial compounds. Mutant strains of a soil-isolated Streptomyces species that does not produce antibacterials synthesize a previously unknown class of antibacterial, which we name piperidamycin. Overall, 6% of non-Streptomyces actinomycetes species and 43% of Streptomyces species that do not produce antibacterials are activated to produce them. The antibacterial-producing mutants all carried mutations in RNA polymerase and/or the ribosomal protein S12.

Production of bioactive compounds based on phylogeny in the genus Penicillium preserved at NBRC.

Penicillium strains (n=394) preserved at NBRC (the NITE Biological Resource Center) were compared as to groupings (11 species-clusters) based on phylogeny and the production of bioactive compounds. The strains in two clusters, of which P. chrysogenum and P. citrinum are representative, showed higher rates of positive strains with multi-biological activities.

FR209602 and related compounds, novel antifungal lipopeptides from Coleophoma crateriformis no.738. I. Taxonomy, fermentation, isolation and physico-chemical properties.

Novel antifungal lipopeptides, FR209602, FR209603 and FR209604, were isolated from the fermentation broth of a fungal strain No. 738 which was identified as Coleophoma crateriformis from morphological and physiological characteristics. The antibiotics were purified by solvent extraction, HP-20, YMC-ODS and silica gel column chromatography and lyophilization. These compounds were structurally similar to FR901379 previously reported by ourselves which had a sulfate residue in the cyclic peptide portion.

FR227673 and FR190293, novel antifungal lipopeptides from Chalara sp. No. 22210 and tolypocladium parasiticum No. 16616.

Novel antifungal lipopeptides, FR227673 and FR190293, were isolated from the fermentation broths of fungal strains Chalara sp. No. 22210 and Tolypocladium parasiticum No. 16616, respectively. These compounds have the same cyclic peptide nuclear structure as FR901379, with different side chains, and showed antifungal activity against Aspergillus fumigatus and Candida albicans attributed to inhibition of 1,3-beta-glucan synthesis.

FR220897 and FR220899, novel antifungal lipopeptides from Coleophoma empetri no. 14573.

Novel antifungal lipopeptides, FR220897 and FR220899, were isolated from the fermentation broth of a fungal strain No. 14573. This strain was identified as Coleophoma empetri No. 14573 from morphological and physiological characteristics. FR220897 and FR220899 showed antifungal activities against Aspergillus fumigatus and Candida albicans attributed to inhibition of 1,3-beta-glucan synthesis. Furthermore, FR220897 was effective in a murine model of systemic candidiasis.

FR258900, a novel glycogen phosphorylase inhibitor isolated from Fungus No. 138354. I. Taxonomy, fermentation, isolation and biological activities.

FR258900 is a novel glycogen synthesis activator produced by Fungus No. 138354. This compound was isolated from the culture broth by solvent extraction and reverse-phase column chromatography. FR258900 stimulated glycogen synthesis and glycogen synthase activity in primary rat hepatocytes. FR258900 exhibited a potent inhibitory effect on the activity of liver glycogen phosphorylase, suggesting that this compound may activate hepatic glycogen synthesis via glycogen phosphorylase inhibition. Thus, this glycogen phosphorylase inhibitor may be useful in the treatment of postprandial hyperglycemia in type 2 diabetes.

The novel gluconeogenesis inhibitor FR225654 that originates from Phoma sp. no. 00144. I. Taxonomy, fermentation, isolation and physico-chemical properties.

FR225654, a novel gluconeogenesis inhibitor, was isolated from the culture broth of Phoma sp. No. 00144 and purified by adsorptive resin and reverse-phase column chromatography. This compound is a potent inhibitor of gluconeogenesis and is a promising candidate of anti-diabetic agent.

FR171456, a novel cholesterol synthesis inhibitor produced by Sporormiella minima No. 15604. I. Taxonomy, fermentation, isolation, physico-chemical properties.

FR171456 and FR173945, novel and potent cholesterol synthesis inhibitors, have been isolated from the fermentation broth of a fungal strain No. 15604. This strain was identified Sporormiella minima from its mycological characteristics. FR171456 and FR173945 strongly inhibited cholesterol synthesis in human hepatoma cell line Hep G2. These compounds also have in vitro antifungal activity against Candida albicans and Aspergillus fumigatus.

FR901512, a novel HMG-CoA reductase inhibitor produced by an agonomycetous fungus No. 14919. II. Taxonomy of the producing organism, fermentation, isolation and physico-chemical properties.

Novel compounds FR901512 and FR901516 were isolated from the fermentation broth of agonomycete strain No. 14919. FR901512 and FR901516 possess unique tetralin ring in their structure. These compounds were potent inhibitors of the cholesterol synthesis in human hepatoma cell line Hep G2. FR901512 shows strong 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitory activity with an IC50 value of 0.95 nM.

The novel gluconeogenesis inhibitors FR225659 and related compounds that originate from Helicomyces sp. No. 19353. I. Taxonomy, fermentation, isolation and physico-chemical properties.

FR225659 and four related compounds are novel gluconeogenesis inhibitors that consist of a novel acyl-group and three abnormal amino acids. They were isolated from the culture broth of Helicomyces sp. No. 19353 and can be purified by absorptive resin and reverse-phase column chromatography. They are potent inhibitors of gluconeogenesis in primary cultured rat hepatocytes and thus may be useful as anti-diabetic agents.

FR235222, a fungal metabolite, is a novel immunosuppressant that inhibits mammalian histone deacetylase (HDAC). I. Taxonomy, fermentation, isolation and biological activities.

A cyclic tetrapeptide FR235222, a novel immunosuppressant, has been isolated from the fermentation broth of a fungus, Acremonium sp. No. 27082. FR235222 showed potent and selective inhibitory effects on both T cell proliferation and lymphokine production. Further study has revealed this compound exhibits potent inhibitory effects on the activity of mammalian histone deacetylases (HDACs).