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Mitochondria isolated from Neurospora crassa were purified by centrifugation in a Percoll density gradient. Enzyme activities and cytochrome differential spectra revealed a high purity of the mitochondria. As compared with a crude mitochondrial fraction the purified mitochondria exhibited a high respiratory activity and a fine ADP/O ratio. Electrophoresis of nucleic acids demonstrated the absence of cytoplasmic rRNA. [ABSTRACT FROM AUTHOR]

Phosphatidylcholine is one of the most frequent phospholipid components of the inner mitochondrial membrane of Neurospora crassa. Quantitative analysis of phospholipids of the wild strain of Neurospora crassa and of its two cho mutants showed that these strains did not significantly differ in the content of phosphatidylcholine. Mutants cultivated in a medium without choline contained, as compared with the wild strain, an increased amount of phosphatidylserine and a decreased quantity of phosphatidic acid. Respiratory activity increased and sensitivity to inhibitors of respiration changed. It is likely that the presence of choline in the growth medium exerts a regulatory effect on the cell metabolism of these mutants. [ABSTRACT FROM AUTHOR]

Colonial growth of Neurospora sitophila phenotypically induced by ramihyphin A is accompanied by marked changes in the contents of DNA, RNA and proteins in the mycelium, and in the relative proportion of hexoses in cell wall hydrolysates. The glucosamine/glucose ratio is also characteristic for colonial growth. X-ray analysis of cell walls showed that ramihyphin A suppresses the crystalline arrangement of chitin in cell walls. A combination of microbiological, biochemical and physico-chemical methods yielded a general picture of the changes accompanying the colonial growth of Neurospora sitophila. [ABSTRACT FROM AUTHOR]

Ramihyphin A at subfungistatio concentrations stimulates ramification of hyphae of filamentous fungi. Stimulation of terminal ramification of hyphae that can be observed particularly in phytopathogenic fungi is most frequent. Hyphae of Microsporon canis, Trichophyton mentagrophytes, Blastomyces dermatitidis, Coccidioides immitis and Histoplasma capsulatum ramify intensively laterally. Stimulation of the lateral ramification was observed in Monilia fructigena, Penicillium marneffei and Penicillium chrysogenum. The antibiotic induces also formation of vesicular structures in phytopathogens. Due to the substantial ramification of hyphae, both terminal and lateral, the growth of colonies is interrupted. The addition of the antibiotic to a growing colony of Botrytis cinerea induces dichotomic ramification of terminal hyphae after 3 h of growth. Lateral hyphae begin to grow later and further ramify dichotomically. Dense bundles of ramified hyphae are formed after 24 h due to the unbalanced ramification and the colony no longer increases its size. [ABSTRACT FROM AUTHOR]

Fusarium sp. S-435 produces a group of related antifungal antibiotics. Three components of a mixture were isolated in a pure state from the mycelium and cultivation medium of the productive strain: ramihyphins A, B and C. Another two components (D and E) were demonstrated by thin-layer chromatography. Ramihyphin A is the main component of the mixture. Its basic physical and chemical properties are presented. The antibiotic is not active against bacteria, yeast-like microorganisms, oomycetes and several protozoa. It inhibits the growth of higher filamentous fungi, stimulating ramification of hyphae when used at subfungistatic concentration. Ramihyphin A does not inhibit germination of conidia of sensitive fungi but stops their growth after their germination. Blastomyces dermatitidis, Coccidioides immitis and Histoplasma capsulatum belong to most sensitive pathogenic fungi in vitro. Ramihyphin A inhibits considerably the growth of the following phytopathogenic fungi: Stereum hirsutum, Neurospora sitophila, Botrytis cinerea, Monilia fructigena and Alternaria tenuis. The antibiotic exhibits antifungal effects also in vivo and is relatively little toxic for HeLa cells. [ABSTRACT FROM AUTHOR]

The lipid constituents of Penicillium cyaneum during the production phase of the macrolide antibiotic cyanein have been studied. Triglycerides were the main components of the neutral lipids and phosphatidyl ethanolamine was the major constituent of the polar lipids. The fatty acid pattern showed a similarity to those of several other fungi. No unusual fatty acids as possible precursors of the cyanein molecule were found. Palmitic, stearic, oleic and linoleic acids were the major fatty acids present. The course of linoleic acid production was very similar to that of cyanein, while the relative percentages of the other major fatty acids showed only slight variations during the cyanein production phase. [ABSTRACT FROM AUTHOR]

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Copyright of Folia Microbiologica is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)