1. The production of penicillin N and cephalosporin C by two mutants of a (ephalo8porium sp. has been studied with cultures grown in a chemically defined medium and with suspensions of washed mycelium in water or a buffered salt solution. 2. Antibiotic synthesis began at an early stage of growth and its rate per unit weight of mycelium appeared to pass its maximum as morphological changes were ...

1. The production of penicillin N, but not that of cephalosporin C, was inhibited by the addition of d-valine to suspensions in water of washed mycelium of Cephalosporium sp. 8650. The production of cephalosporin C was selectively inhibited by gamma-hydroxyvaline. 2. l-[(14)C]Valine was taken up rapidly and virtually completely by suspensions of washed mycelium but d-[(14)C]valine and alpha-oxo...

Pamamycin-607, which showed aerial mycelium-inducing activity, has been isolated from Streptomyces alboniger IFO 12738. At 0.1 microgram/disc it induces aerial mycelia in the aerial mycelium-negative strain of S. alboniger but inhibits growth of the substrate mycelia at 10 micrograms/disc. It also acts as an antibiotic against some fungi and bacteria. When KMnO4 was partitioned with pamamycin-6...

Experiments were carried out to test the aqueous extracts of twenty plants for their antifungal activity against Fusarium solani the causal of dry rot disease of potato. The obtained results showed a differential activity of the plant extracts against the mycelium growth. The combined leaf extracts of Lawsonia alba and stem extracts of Acacia catechu in general showed a strong enhancement in ac...

Streptomycetes are prokaryotic microorganisms that exhibit a complex, mycelial fungus-like cycle of morphological differentiation. Development involves at least two spatially separated types of cells: the branching hyphae of the substrate mycelium, which penetrate the stratum upon which the colony feeds, and the upwardly protruding hyphae of the aerial mycelium, which undergo metamorphosis into...

For the successful operation of aerobic fermentations it is essential to supply the microorganiisms with sufficient oxygen to meet their requirements at any stage in the process. Failure to supply enough oxygen may lead to undesirable changes in enzymatic makeup (Rolinson, 1952) or death of the organisms (Hromatka et al., 1951), with a subsequent lower yield of the desired product. In general, ...

We present a strategy to recover high molecular weight genomic DNA from large numbers of isolates of Phytophthora. Included are steps for generating mycelial mass in 24-well reuseable deep well plates, efficient lyophilization and disruption of the mycelium and genomic DNA extraction with 96-well glass fiber filter plates. The resulting DNA is consistently high molecular weight and is suitable ...

In a preliminary communication (Ghosh, 1959) it was reported that fresh and wet mycelium of Penicillium chrysogenum, as obtained from a rotary filter in a penicillin plant, could be well utilized as the sole source of nitrogen for penicillin production by the mold either in shaken flask or in aerated and agitated large fermentors. The waste mycelium did not need any pretreatment whatsoever and ...

A method for the quantitative determination of leucogenenol, a leucocytosis-inducing compound produced by Penicillium gilmanii, has been developed. The formation of leucogenenol in P. gilmanii and its diffusion into the culture fluid has been followed over a period of 12 weeks. The highest concentration of leucogenenol was found in the mycelium of rapidly growing cultures. The greatest concentr...