Structure and chemical composition of yeast chlamydospores of Aureobasidium pullulans

1973 ◽  
Vol 19 (2) ◽  
pp. 163-168 ◽  
Author(s):  
Robert G. Brown ◽  
Louis A. Hanic ◽  
May Hsiao
Keyword(s):  
Cell Walls ◽  
Nitrate Nitrogen ◽  
Nitrogen Nutrition ◽  
Nitrogen Sources ◽  
Dry Weight ◽  
Cell Types ◽  
Ammonium Nitrogen ◽  
Wall Layer ◽  
Outer Cell ◽  
Yeastlike Cells

Cellular form in Aureobasidium pullulons can be partially controlled by nitrogen nutrition. Ammonium nitrogen supports a mixture of filamentous and yeastlike growth, whereas only a few filaments develop on nitrate nitrogen. On nitrate 97% of the cell material consists of a mixture of yeastlike cells and chlamydospores. Chlamydospores are produced on both nitrogen sources; however, with ammonium nitrogen chlamydospores occur in an intercalar position, whereas nitrate nitrogen supports development of chlamydospores as separate structures containing one, two, or occasionally three cells. This mode of production allows separation of yeast chlamydospores from other cell types and subsequent isolation of their cell walls. Yeast chlamydospores and filaments have an electron dense, melanin-rich, granular, outer cell-wall layer which yeastlike cells lack. This granular material is also found in cross walls of filaments and chlamydospores. Glucose is the main component of chlamydospore walls and accounts for 36% of the dry weight. Yeastlike cell walls contain only 13% glucose, but more mannose, galactose, and bound lipid. Most of the glucan portion of chlamydospore walls is insoluble in dilute alkali; methylation analysis indicates that this material contains linear chains of (1 → 3) and (1 → 6) linked glucose. About one residue in five forms a branch point having both (1 → 3) and (1 → 6) linkages.

The growth of Luffa aegyptiaca in response to various nitrogen sources and concentrations

1985 ◽  
Vol 63 (12) ◽  
pp. 2283-2287
Author(s):  
Olubukanla T. Okusanya ◽  
Olusola O. Lakanmi
Keyword(s):  
Nitrate Nitrogen ◽  
Nitrogen Concentration ◽  
Nitrogen Sources ◽  
Ammonium Nitrogen ◽  
Lateritic Soil ◽  
Sand Culture ◽  
Growth Media ◽  
Growth Responses ◽  
Poor Growth ◽  
Luffa Aegyptiaca

The growth responses of Luffa aegyptiaca to various nitrogen sources and concentrations were investigated. In sand culture at high concentrations of nitrogen, the species showed equally favourable responses to nitrate nitrogen (KNO3 or Ca(NO3)2), ammonium nitrogen ((NH4)2SO4), and the combination of nitrate and ammonium nitrogen (NH4NO3). There was poor growth in response to NaNO3, CO(NH2)2, and a solution lacking nitrogen. In lateritic soil, the species responded better to ammonium nitrogen and the combination of nitrate and ammonium nitrogen than to nitrate nitrogen. Growth was generally poorer in lateritic soil than in sand. Neither the nitrogen sources nor their concentrations had any significant effect on root weight or the leaf weight ratio. There was a significant decrease in growth as nitrogen concentration decreased in KNO3 and Ca(NO3)2 treatments but it was only at the low concentrations of (NH4)2SO4 and NH4NO3 that growth was significantly reduced. The shoot: root mass ratio decreased as nitrogen concentration decreased. The nature of the growth media and the ecological habit of the species are used to partly explain its responses to different nitrogen sources and concentrations. The possible application of these results to increasing the production of L. aegyptiaca is also discussed.

Effects of nitrogenous compounds on sclerotium formation in Aspergillus niger

1968 ◽  
Vol 14 (11) ◽  
pp. 1253-1258 ◽  
Author(s):  
V. P. Agnihotri
Keyword(s):  
Amino Acids ◽  
Aspergillus Niger ◽  
Basal Medium ◽  
Nitrogen Sources ◽  
Dry Weight ◽  
Ammonium Nitrogen ◽  
Nitrogenous Compounds ◽  
Alkaline Side ◽  
Sclerotium Formation ◽  
Ammonium Compounds

The effects of different nitrogen sources on growth and sclerotial production by Aspergillus niger were determined on a synthetic agar medium. The organism used inorganic, organic, and ammonium nitrogen for growth and sclerotial production. Among the ammonium compounds tested, the chloride, phosphate, sulfate, and carbonate were used poorly, but the nitrate was well utilized. Addition of organic acids to ammonium compounds increased sclerotial production. Raising the concentration of sodium nitrate to a certain level (0.15%) increased the number of sclerotial initials and the number and weight of those which matured. Sodium nitrite curtailed mycelial growth and prevented production of sclerotia. Utilization of nitrite was accelerated by adjusting the pH on the alkaline side from 7.5 to 9.0. Urea supported poor sclerotial production; thiourea inhibited it. Of the amino acids, histidine yielded the most and arginine the least number of sclerotia. In lysine medium, the white cottony sclerotial initials remained fluffy even after 20 days. Sclerotial production decreased significantly when proline, glutamic acid, or leucine were omitted from the basal medium containing 10 amino acids. In general, no correlation existed between the number of sclerotia formed and the dry weight they attained on different nitrogen sources. With certain nitrogen sources sclerotial initials failed to mature.

scholarly journals Influence of lime on the accumulation of mineral nitrogen in incubation experiments of peat soils

1957 ◽  
Vol 29 (1) ◽  
pp. 229-237
Author(s):  
Armi Kaila ◽  
Sylvi Soini
Keyword(s):  
Nitrate Nitrogen ◽  
Nitrogen Nutrition ◽  
Ammonium Nitrogen ◽  
Mineral Nitrogen ◽  
Peat Soils ◽  
Prolonged Incubation ◽  
The Third ◽  
Nitrite Nitrogen ◽  
Incubation Experiments ◽  
Three Samples

In the present paper the effect of lime on the mobilization of peat nitrogen was studied using incubation experiments under laboratory conditions. In the first experiment in which 13 samples of virgin peat soils were incubated for four months at 7°C, lime caused a marked nitrification of ammonium nitrogen in three samples, and a fairly low increase in the ammonium nitrogen content of five samples. The accumulation of total mineral nitrogen was benefited by lime in five samples and only in one of them could a marked increase be detected. In the second experiment the amounts of lime applied to five peat samples corresponded to 4000, 8000 or 12 000 kg/ha of CaCO3. At the end of an incubation period of four months at 9—15°C the total amounts of mineral nitrogen accumulated did not depend on the fate of liming, as did the nitrification in SCp-and BCp-samples, and also, in part, in the Sp- and CSp-samples. After the prolonged incubation up to 12 months the amount of lime applied had little or no effect upon the accumulation of nitrate-nitrogen or total mineral nitrogen except in the SCp-sample in which a positive correlation between these figures existed. Traces of nitrite-nitrogen were detected in some of the samples incubated for four months with the heaviest applications of lime. In the third experiment carried out at 7°C the treatment with lime was equal to that in the second series, but half of the pots were treated with ammonium nitrate corresponding to 100 kg/ha of nitrogen. The effect of lime on the treated samples appeared to be similar to that in the untreated one. Owing to the large variation, the fate of applied mineral nitrogen could not be distinctly detected. The loss of ammonium nitrogen through volatilization from the most heavily limed pots may be a possible explanation for the lower amounts of total mineral nitrogen in the incubated BCp-samples. Some reasons for these variable results are discussed and attention is also paid to the importance of nitrification on the nitrogen nutrition of plants.

scholarly journals Adhesion of the Entomopathogenic Fungus Beauveria (Cordyceps) bassiana to Substrata

2005 ◽  
Vol 71 (9) ◽  
pp. 5260-5266 ◽  
Author(s):  
Diane J. Holder ◽  
Nemat O. Keyhani
Keyword(s):  
Entomopathogenic Fungus ◽  
Rational Design ◽  
Sodium Dodecyl ◽  
Cell Types ◽  
Wall Layer ◽  
Outer Cell ◽  
Submerged Cultures ◽  
Hydrophilic Surfaces ◽  
Polar Surfaces ◽  
Aerial Conidia

ABSTRACT The entomopathogenic fungus Beauveria bassiana produces at least three distinct single-cell propagules, aerial conidia, vegetative cells termed blastospores, and submerged conidia, which can be isolated from agar plates, from rich broth liquid cultures, and under nutrient limitation conditions in submerged cultures, respectively. Fluorescently labeled fungal cells were used to quantify the kinetics of adhesion of these cell types to surfaces having various hydrophobic or hydrophilic properties. Aerial conidia adhered poorly to weakly polar surfaces and rapidly to both hydrophobic and hydrophilic surfaces but could be readily washed off the latter surfaces. In contrast, blastospores bound poorly to hydrophobic surfaces, forming small aggregates, bound rapidly to hydrophilic surfaces, and required a longer incubation time to bind to weakly polar surfaces than to hydrophilic surfaces. Submerged conidia displayed the broadest binding specificity, adhering to hydrophobic, weakly polar, and hydrophilic surfaces. The adhesion of the B. bassiana cell types also differed in sensitivity to glycosidase and protease treatments, pH, and addition of various carbohydrate competitors and detergents. The outer cell wall layer of aerial conidia contained sodium dodecyl sulfate-insoluble, trifluoroacetic acid-soluble proteins (presumably hydrophobins) that were not present on either blastospores or submerged conidia. The variations in the cell surface properties leading to the different adhesion qualities of B. bassiana aerial conidia, blastospores, and submerged conidia could lead to rational design decisions for improving the efficacy and possibly the specificity of entomopathogenic fungi for host targets.

Mycoviruses of Penicillium stoloniferum: influence of carbon–nitrogen nutrition upon replication

1978 ◽  
Vol 24 (8) ◽  
pp. 947-953 ◽  
Author(s):  
R. W. Detroy ◽  
D. M. DeMarini ◽  
P. E. Still
Keyword(s):  
Virus Replication ◽  
Nitrogen Nutrition ◽  
Nitrogen Sources ◽  
Dry Weight ◽  
Growth Conditions ◽  
Minimal Growth ◽  
Carbon Nitrogen Ratio ◽  
Nitrogen Ratio ◽  
C And N ◽  
Penicillium Stoloniferum

Carbon–nitrogen ratio experiments indicate that limiting nutrition not only hinders Penicillium stoloniferum host proliferation but reduces total PsV-F and PsV-S virus replication. Results of C-N experiments show a pH-induced autolysis and virus release at minimal C levels. Maximal PsV-F levels and biomass were obtained with glucose and sucrose as C sources. Oleic acid also yielded high biomass and PsV-F yields. Yeast extract was an excellent N source; 2.83 g dry weight biomass and 87 A260 units PsV-F after 96 h of growth. Other nitrogen sources, including amino acids, supported only minimal growth and virus replication. The autolysis phenomenon is pH, not viral-induced. High C and N will support maximal growth and unrestricted virus replication with no cellular lysis. Under low C growth conditions, the replication of PsV-S is favored coupled with high pH and autolysis.

Nitrogen requirements of the genus Linderina

1970 ◽  
Vol 48 (4) ◽  
pp. 695-698 ◽  
Author(s):  
R. C. Stephen ◽  
Christina Chan
Keyword(s):  
Glutamic Acid ◽  
Organic Nitrogen ◽  
Liquid Culture ◽  
Growth Response ◽  
Nitrate Nitrogen ◽  
Nitrogen Sources ◽  
Ammonium Nitrogen ◽  
Good Growth ◽  
Poor Growth ◽  
Better Than

The influence of different nitrogen sources on the growth of Linderina was examined in liquid culture. Both species of Linderina were unable to assimilate nitrate nitrogen and nitrite seemed to be toxic. Ammonium nitrogen was used but the growth response was considerably lower than that with some organic nitrogen materials. Inclusion in the growth medium of succinic acid as a carbon source failed to improve the assimilation of ammonium.Amino nitrogen as aspartic acid and asparagine gave good growth though not as good as with L- or DL-glutamic acid. The response to DL-glutamic acid was markedly better than to the L-isomer whereas the D-isomer gave relatively poor growth.

Ammonium fixation and availability in some cereal producing soils in Queensland.

Soil Research ◽  
1972 ◽  
Vol 10 (2) ◽  
pp. 197 ◽  
Author(s):  
AS Black ◽  
SA Waring
Keyword(s):  
Nitrate Nitrogen ◽  
Sequential Sampling ◽  
Nitrogen Sources ◽  
Ammonium Nitrogen ◽  
Low Density ◽  
Air Drying ◽  
Ammonium Fixation ◽  
Intensive Cropping ◽  
Almost All ◽  
Pot Culture

Native fixed ammonium nitrogen and fixation of added ammonium nitrogen were studied in 24 Queensland cereal producing soils. The availabiiity of both forms of fixed ammonium nitrogen to wheat was investigated using a montmorillonitic soil under pot culture. Fixation and release of fertilizer ammonium nitrogen were followed in the soil by sequential sampling during crop growth. All soils contained native fixed ammonium nitrogen (6-107 p.p.m. nitrogen, mean 39 p.p.m. nitrogen). Fixation of added ammonium nitrogen was only significant in high clay montmorillonitic soils. Under moist conditions an average of 5% (200 p.p.m. nitrogen added) and 1% (4000 p.p.m. nitrogen added) was fixed. Fixation increased threeto ten-fold following air drying. Intensive cropping only released small but non-significant amounts of native fixed ammonium nitrogen. Of the 15% of added ammonium nitrogen which was fixed, only 50% was released by a single low density cropping causing less nitrogen uptake by wheat tops from ammonium compared with nitrate nitrogen sources. Intensive or successive cropping released almost all recently fixed ammonium nitrogen.

scholarly journals 1021 RECENT ADVANCES IN NATIONWIDE STUDIES OF CRANBERRY NITROGEN NUTRITION

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 574e-574
Author(s):  
J. R. Davenport ◽  
C. J. DeMoranville
Keyword(s):  
Nitrate Nitrogen ◽  
Nitrogen Nutrition ◽  
Reductase Activity ◽  
Weather Conditions ◽  
Ammonium Nitrogen ◽  
Fruit Crops ◽  
The Past ◽  
Low Levels ◽  
The Difference ◽  
Nitrogen Rates

Like many fruit crops, the difference between vegetative and reproductive production in cranberry is strongly influenced by nitrogen supply, as is fruit quality. However, the optimal supply for this crop has not been established. Further, there have been mixed results on whether or not cranberry can metabolize nitrate nitrogen. Within the past 6 years there has been an upsurgence in research on cranberry nitrogen nutrition and it has started to provide answers to some of these unknowns. Results from the lab of L. Peterson (U Wi - Madison) have shown that cranberry will take up nitrate nitrogen, however the uptake is minimal unless ammonium nitrogen is present. The work from Peterson's lab has also shown that there is some nitrate reductase activity in cranberry leaves, albeit at very low levels. Work that we have conducted and work by J. Hart's group (OSU) have been the basis for establishing optimal nitrogen rates and timings for cranberry in the different growing areas in North America. Overall, the work from these different groups has shown that except in extreme situations, 22 - 33 kg N/ha is optimal for cranberry production. However, timing of application varies widely due to weather conditions in the different growing areas.

Gymnomitrion fissum (Gymnomitriaceae, Marchantiophyta) — a new species with fissured leaf surface from China

2017 ◽  
Vol 51 ◽  
pp. 274-280
Author(s):  
A. D. Potemkin ◽  
Yu. S. Mamontov ◽  
N. S. Gamova
Keyword(s):  
New Species ◽  
Cross Sections ◽  
Cell Walls ◽  
Leaf Surface ◽  
Outer Cell ◽  
Sem Images ◽  
Cell Lumen ◽  
A New Species ◽  
Surface Comparison

Study of selected specimens of Gymnomitrion collected by D. G. Long in Yunnan, China, revealed a new species, G. fissum Mamontov et Potemkin, sp. nov., with a fissured leaf surface. Comparison of SEM images of the leaf surface and leaf cross sections shows that the leaf surface of G. fissum is different from that of other known species with a superficially similar leaf surface, i. e. Mylia taylorii, M. verrucosa s. l. and Trabacellula tumidula. It has fissures around the cell lumen rather than grids and perforations. Outer cell walls of Gymnomitrion fissum are much thicker than in Mylia taylorii, M. verrucosa s. l. and Trabacellula tumidula, and their outer layers tend to be partly or completely caducous. G. fissum is related to the group of species assigned to the former genus Apomarsupella.

The ultrastructure of the outer cell wall-layer ofChlorella mutants with and without sporopollenin

1981 ◽  
Vol 138 (1-2) ◽  
pp. 121-137 ◽  
Author(s):  
J. Burczyk ◽  
M. Hesse
Keyword(s):  
Cell Wall ◽  
Wall Layer ◽  
Outer Cell ◽  
Cell Wall Layer ◽  
Outer Cell Wall
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