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D J Niederpruem

Publications and source records attributed to D J Niederpruem.

At least 19 recordsLinked to original sources
PubMed1980

Direct studies of dikaryotization in Schizophyllum commune. I. Live inter-cellular nuclear migration patterns.

Compatible matings of Schizophyllum commune were performed on glucose-peptone-yeast extract medium appended with gelatin (18%) and studied by phase contrast microscopy during nuclear migration. Three categories of nuclear migration were observed. Type I involved a pulsatile jerking of the entire cytoplasmic contents of the hypha, changed direction periodically, and, during periods of cytoplasmic tranquility, the nucleus continued to migrate. Type II A migration of nuclei occurred in the absence of visible cytoplasmic flow. Both Type I and Type II A nuclear movements exceeded the hyphal growth rate by 10--20-fold. Type II B nuclear migration also occurred in the absence of visible cytoplasmic flow and the velocity was within the range of the hyphal growth rate. No specific organelles that were detected either directed or facilitated Type II A or Type II B nuclear movements. The nucleolus could either lead or trail relative to the direction of nuclear movement. Nuclear migration can be attributed to both cytoplasmic flow and self motility, depending upon the particular regions of the migration hypha in which it occurs.

Agaricales↗
PubMed1980

Direct studies of dikaryotization in Schizophyllum commune. II. Behavior and fate of multikaryotic hyphase.

The growth, duplication and fate of multikaryotic hyphae bearing true clamp connections, as derived from compatible matings of Schizophyllum commune, were studied by phase contrast microscopy. The nuclei (N) of multikaryotic apices maintained a near central position during hyphal growth. True clamp connection formation occurred with near synchronous mitosis followed by septal synthesis across the clamp neck and main hyphal axis. Nuclear progeny after mitosis in a hexakaryon included 6 N in the apex, 1 N in the clamp and 5 N in the penultimate cell; the solitary nucleus in the clamp later entered the penultimate cell. Similar events occurred for clamp connection formation and mitosis in the trikaryon, quadrikaryon or pentakaryon, whether in the apex or primary branches. Nuclear content of the multikaryotic apex (2 N through 10 N) had no apparent effect on the rate of individual hyphal growth. Reduction of the nuclear number in a trikaryon occurred by long-term entrapment of a solitary nucleus in the clamp and subsequent outgrowth of the dikaryotic penultimate cell. Occasionally, more than one nucleus became entrapped in the clamp cell. The ephemeral nature of the multikaryon was indicated by the fact that older cultures appeared to be exclusively dikaryotic hyphae at the colony periphery.

Agaricales↗
PubMed1980

Temporal accumulation of mannitol and arabitol in Geotrichum candidum.

The temporal depletion and accumulation of polyols were investigated in the fungus Geotrichum cnadidum. The major intracellular polyols were tentatively identified by paper chromatography as mannitol and arabitol. Inositol was also present in small quantities, and trehalose was also detected in appreciable concentrations. Germination and vegetative growth depended on the type and concentration of the sole exogenous carbon source. Mannitol occurred in arthrospores at 9.4% of the dry weight after several days growth in 2% (w/v) glucose solid medium, and became depleted during germination and vegetative growth in liquid medium containing 2% (w/v) glucose, 2% (w/v) sodium acetate or 25% (w/v) glucose as sole carbon source. This hexitol latter accumulated during arthrosporulation. The depletion and accumulation of ethanol-soluble carbohydrate believed to be primarily trehalose was temporally similar to that of mannitol. Arabitol accumulated intracellularly during germination and vegetative growth in sodium acetate medium and 25% glucose medium. This pentitol was not detected intracellularly at any culture age during growth in 2% glucose medium. Prolonged incubation of the culture in 25% glucose medium after stationary phase was reached resulted in the gradual disappearance of arabitol from the arthrospores simultaneously with an increase in intracellular mannitol. In comparison, ethanol-soluble carbohydrate did not change with prolonged incubation in this medium.

Arabinose↗
PubMed1979

Control of exocellular proteases in dermatophytes and especially Trichophyton rubrum.

The production of proteases was investigated during growth of dermatophytic fungi with special emphasis on Trichophyton rubrum. Exogenous glucose suppressed elastase production in all dermatophytes examined. The production of protease active guinea pig hair in keratin-salts broth by Microsporum gypseum. Trichophyton mentagrophytes and T. rubrum was also suppressed by glucose. Various carbohydrates added to keratin-salts broth curtailed protease production by T. rubrum as did individual amino acids but ammonium phosphate did not. Enzyme activities against guinea pig hair were compared in twenty-one diverse clinical isolates of T. rubrum cultured in keratin-salts broth. Activity also occurred towards casein, bovine serum albumin, keratin, collagen and elastin after keratin-growth. Studies concerning the properties of enzyme activities in culture filtrates of T. rubrum after keratin-growth suggested that multiple proteases occurred here. Hydrolysis of guinea pig hair and elastin were optimal at pH7 while keratinase was most active at alkaline pH. Divalent cations stimulated protease(s). Ferric ion and mercuric ion stimulated keratinase but were inhibitory to guinea pig hair hydrolysis and elastase. Chelating agents inhibited elastase and the hydrolysis of guinea pig hair more severely than keratinase and all of those effects were reversed by excess calcium. A serine-protease inhibitor, phenylmethylsulfonylfluoride (PMSF), curtailed keratinase but was less inhibitory to elastase and guinea pig hair hydrolysis. Soybean trypsin inhibitor arrested each protease.

Animals↗
PubMed1976

Enzyme activities associated with arabitol and mannitol biosynthesis and catabolism in Schizophyllum commune.

Enzymes of polyol metabolism were studied in basidiospore germination of Schizophyllum commune during periods of in vivo arabitol and mannitol pool depletion (growth on glucose-asparagine) and during their subsequent synthesis (growth on acetate-NH+4). Optimal conditions for assays were established and specific activities of enzymes employing D-arabitol, D-mannitol, D-ribulose, D-fructose and D-xylulose as substrates. were traced. Inquiries into the products formed during these reactions showed that D-ribulose generated arabitol while D-fructose produced mannitol with D-xylulose giving rise to xylitol. The dehydrogenase reactions were further investigated using polyacrylamide disc gel electrophoresis. Here was revealed the existence of at least two separate enzymatic activities pertaining to the catabolism of arabitol and mannitol. Also noted were the electrophoretic patterns when D-sorbitol, ribitol, xylitol and ethanol were used as substrates

Acetates↗
PubMed1976

Ultrastructural aspects of ascosporulation in Arthroderma quadrifidum (=Trichophyton terrestre).

The ultrastructural features of developing and mature ascospores were delineated after mating Arthroderma quadrifidum on pablum cereal agar. Incipient ascospores each contained a granulated nucleus bounded by a nuclear envelope while presumptive ascospore cytoplasm was bounded by a double membrane and resided in glycogen-rich epiplasm of the ascus. Mature ascospores contained nuclei and mitochondria while the ascus epiplasm still retained abundant inclusions. The ascospore wall demonstrated the presence of heterogeneous material between the plasmalemma and the outer spore membrane which appeared smooth.

Ascomycota↗
PubMed1975

Origin and ultrastructure of intra-hyphal hyphae in Trichophyton terrestre and T. rubrum.

A cell observation chamber was designed to perform continuous photomicroscopic observations of hyphal anastomosis and the origin of intra-hyphal hyphae in Trichophyton terrestre and T. rubrum. These data were correlated with ultrastructural features of intra-hyphal hyphae. Hyphal fusions occurred commonly in either species of Trichophyton when incubated alone. In T. terrestre, empty phyphal segments adjoined by live units were invaded at the septa from both directions by new hyphal ingrowth. Continuous observations revealed that the intra-hyphal hyphae subsequently anastomosed via a lateral fusion peg. Similar intra-hyphal hyphae were shown in T. rubrum. Electron microscopic studies revealed ascomycetous septa in both conventional hyphae and intra-hyphal hyphae. For the latter, the cytoplasm and wall of the inner hypha were bounded by cytoplasmic organelles and another cell wall of the outer hypha.

Trichophyton↗
PubMed1975

Differentiation in Coprinus lagopus. III. Expansion of excised fruit-bodies.

Fruit-body expansion was studied in Coprinus lagopus (sensu Buller) following surgical procedures. Elongation occurred after denuding mushroom caps of essentially all peripheral scales. Young primordia (1 - 5 mm) failed to develop after vertical bisection. Older primordia (e.g. 10 mm) expanded 3 - 4 fold after vertical bisection or quadrisection, underwent autolysis and basidiospore production. An amorphous brown gel in the stripe lumen disappeared during development of bisected primordia. Stripes isolated from primordia expanded autonomously and exhibited negative geotropism when incubated upside down or when the stripe apex was removed. Displacement of charcoal particles dusted on intact stripes revealed the most active zone of expansion to be the upper mid-region of the stripe. Segmented stripes likewise showed most active elongation in the mid-region. Vertically bisected stripes also expanded.

Agaricales↗
PubMed1970

Ultrastructural changes and biochemical events in basidiospore germination of Schizophyllum commune.

Electron microscopic features and biochemical events were outlined in basidiospore germination of Schizophyllum commune. Normal ultrastructural changes included prominent vacuolization and more abundant endoplasmic reticulum. A lag phase in outgrowth included depletion of cellular reserves of trehalose, mannitol, and arabitol and subsequent increases in ribonucleic acid and protein. Depletion of polyols required exogenous carbon and nitrogen sources and was arrested by protein synthesis antagonists. Outgrowth subsequent to the lag period was accompanied by increased glycogen deposition and alkali-soluble glucan production.

Alcohols↗