Production of thermozymocidin (myriocin) by the pyrenomycete Melanconis flavovirens.

Submerged culture of the pyrenomycete Melanconis flavovirens produces a strongly active antifungal antibiotic. The antibiotic was isolated from the culture mash. In purified compound the physico-chemical characteristics, including 1H NMR spectrum, were estimated.

Flavovirin--a new antifungal antibiotic produced by the pyrenomycete Melanconis flavovirens.

The pyrenomycete Melanconis flavovirens was found to produce a mixture of two antifungal antibiotics. The first has been already described; the antibiotic is identical with thermozymocidin (myriocin). The second antibiotic is a new compound, whose isolation and identification is presented in this paper.

Glucose-2-oxidase activity in mycelial cultures of basidiomycetes.

The activity of intracellular glucose-2-oxidase was tested in 40 species of 26 basidiomycete genera. The enzyme catalyzing the oxidation of D-glucose to the dicarbonyl sugar D-arabino-2-hexosulose was demonstrated in mycelial extracts of 9 species of Aphyllophorales and 6 species of Agaricales cultivated in liquid media. In the majority of species exhibiting this activity hexosulose was detected in the cultivation medium.

Effect of glucitol on the production of mucidin in Oudemansiella mucida.

When studying the biosynthesis of mucidin under production (glucose as the main carbon source) and non-production (glucitol as the main carbon source) conditions it could be shown that the producer, Oudemansiella mucida, utilizes glucitol both for growth and for mucidin biosynthesis. However, the production of mucidin is 10 times lower than on glucose. When the culture was preincubated on glucose and transferred to non-production conditions the negative effect of glucitol could not be demonstrated.

Metabolism of aromatic acids in the antibiotic-producing basidiomycete Oudemansiella mucida.

Aromatic acids were determined in the mycelium and fermentation medium of Oudemansiella mucida. Coumaric acids (both m- and p-), p-hydroxybenzoic acid (salicylic acid) and benzoic acid were found to predominate in the mycelium. Phenylacetic acid represents the main component in the medium.

Effect of tryptophan on the production of mucidin in cultures of basidiomycete Oudemansiella mucida.

Addition of L-tryptophan to cultures of the basidiomycete Oudemansiella mucida brought about a pronounced increase of production of the antibiotic mucidin. The highest increase was reached in the presence of 0.15-0.

Mucidin-nonproducing mutants of oudemansiella mucida.

Mutants of Oudemansiella mucida, blocked in the biosynthesis of the antibiotic mucidin, were obtained at a 0.28% frequency after the application of N-methyl-N'-nitro-N-nitrosoguanidine (MNG) to basidiospores under conditions leading to 0.5--5.

Soluble sugars in the mycelium of the basidiomycete Oudemansiella mucida.

Quantitative gas chromatography was used to determine soluble neutral sugars in an extract of the fungus Oudemansiella mucida grown on a synthetic glucose medium. Apart from the usual fungal sugar components, viz. trehalose, D-glucose, D-mannitol, D-arabinitol, glycerol and inositol, the 6-day-old mycelium contained D-arabino-2-hexosulose (D-glucosone).

Glucose-2-oxidase activity and accumulation of D-arabino-2-hexosulose in cultures of the basidiomycete Oudemansiella mucida.

Submerged cultures of the basidiomycete Oudemansiella mucida, strain III, accumulate D-arabino-2-hexosulose. The maximum yields during cultivations in shaker flasks or in a laboratory fermentor are 6--12 and 15 mg/ml, respectively (20--50% conversion of substrate glucose). The accumulation is transient, the aldoketose being again utilized after glucose exhaustion.

Biosynthesis of fatty acids and sterols in relation to the antibiotic formation in Oudemansiella mucida.

The production of mucidin by the basidiomycete Oudemansiella mucida was negatively influenced by the application of D-glucitol as the main carbon source, the effect being independent of the growth rate of the mycelium. The rate of fatty acid synthesis was measured by incorporation of 1-14C-acetate. After 8 days of cultivation, the amount of fatty acids was approximately half that synthetized during cultivation on glucose.

alpha-Mannosidase and mannanase of some wood-rotting fungi.

Cultivation media from 11 wood-rotting fungi contained alpha-mannosidase and mannanase activity, alpha-Mannosidase was studied in more detail in Phellinus abietis and mannanase was studied more intimately in basidiomycetes Phellinus abietis, Trametes sanguinea and Pholiota aurivella. Suitable cultivation conditions and optimum conditions for the production of alpha-mannosidase and mannanase were determined. Both enzymes are constitutive; mannanase is extracellular, alpha-mannosidase was found in both mycelium and cultivation medium.

Antifungal antibiotic of the Basidiomycete Oudemansiella mucida. III. Nuclei in the hyphae of mono- and dikaryons.

Nuclear ratios were studied in terminal and subterminal cells of various mycelia of the basidiomycete Oudemansiella mucida, the producer of the antifungal antibiotic mucidin (MuciderminR Spofa). The dikaryon, the monokaryon, and the mucidin-producing strain that had been cultivated for a long time under submerged conditions were compared. Dedikaryotization was found to have taken place in the producing strain.

Antifungal antibiotic of the Basidiomycete Oudemansiella mucida. II. Life cycle and fructification of the producing fungus.

The developmental cycle of the fungus Oudemansiella mucida, the producer of a new antifungal antibiotic, was found to be controlled by the mechanism of homogenic tetrapolar incompatibility; under our conditions, the cycle took about 12 weeks to completion. Optimum conditions for a laboratory-scale fructification were investigated. Normal fruiting body formation required sufficient illumination, temperatures below 20 degrees C, and relative humidity in excess of 70%.

Separation and properties of alpha-mannosidase and mannanase from the basidiomycete Phellinus abietis.

Proteins of a crude enzyme preparation obtained from the cultivation medium of the basidiomycete Phellinus abietis were separated by gel filtration and ion-exchange chromatography. The preparation contained a minimum of three enzymes capable of splitting alpha-D-mannosidic bonds: alpha-mannosidase, exomannanase, and endomannanase, which were separated. Some properties of the mannanase complex of the crude enzyme preparation, and of a partially purified alpha-mannosidase were examined.

Lipids in fruiting bodies of the basidiomycete Oudemansiella mucida.

Dried fruiting bodies of the basidiomycete Oudemansiella mucida contain 29.1% total lipids. Their qualitative analysis revealed the presence of mono-, di-, triglycerides, sterols, free fatty acids and sterolesters.