The utilization of L-tryptophan as nitrogen source by Fusarium culmorum, Aspergillus nidulans, and Penicillium italicum

1972 ◽  
Vol 18 (8) ◽  
pp. 1353-1356 ◽  
Author(s):  
J. Coll ◽  
J. A. Leal
Keyword(s):  
Nitrogen Source ◽  
Aspergillus Nidulans ◽  
Fusarium Culmorum ◽  
Dry Weight ◽  
Penicillium Italicum ◽  
Culture Filtrates

Fusarium culmorum reached a maximum dry weight of 60 mg/25 ml, and indolelactic acid (ILA) was found in the culture filtrates during the first 8 days of incubation. Only traces of ILA were detected in the filtrates of Aspergillus nidulans and none in those of Penicillium italicum both of which reached a dry weight of about 90 mg/25 ml.

GROWTH AND METABOLISM OF ASPERGILLUS NIDULANS EIDAM ON DIFFERENT NITROGEN SOURCES IN SYNTHETIC MEDIA CONDUCIVE TO FAT FORMATION

1960 ◽  
Vol 38 (4) ◽  
pp. 613-622 ◽  
Author(s):  
Kaiser Naguib ◽  
Kamel Saddik
Keyword(s):  
Nitrogen Source ◽  
Aspergillus Nidulans ◽  
Ammonium Chloride ◽  
Sodium Nitrate ◽  
Dry Weight ◽  
Ammonium Nitrogen ◽  
High Rate ◽  
Sugar Uptake ◽  
Surface Culture ◽  
Sugar Absorption

Aspergillus nidulans has been grown in surface culture on high-sugar media favorable for fat formation and containing, as nitrogen source, sodium nitrate, ammonium chloride, or asparagine. Growth, sugar and nitrogen uptake, and syntheses of carbohydrates, proteins, and fat were all followed over an incubation period of 20 days. In the early stages, growth was influenced by the nature of the nitrogen source, being highest on asparagine and lowest on ammonium chloride, with the same sugar uptake. Later, dry weight increase proceeded at a high rate on asparagine, at a moderate rate on sodium nitrate, and it almost stopped on ammonium chloride, where the pH dropped to a very low value. At this stage, increase in dry weight followed sugar absorption, and was due to accretion of non-nitrogenous compounds.Asparagine media were by far superior to nitrate or ammonium media for fat formation. Protein and carbohydrate contents were higher in nitrate- than in asparagine- or ammonium-fed mycelial felts. All synthetic processes almost stopped in ammonium cultures after the early growth phase. It seems that the attitude of the fungus towards ammonium nitrogen could not be fully manifested due to restricted growth, and therefore it is suggested that no definite conclusions with regard to ammonium utilization by Aspergillus nidulans can be drawn unless the pH of the medium is controlled and growth on ammonium nitrogen made possible.

scholarly journals Studies on the Role of the are a Gene in the Regulation of Nitrogen Catabolism in Aspergillus nidulans

1975 ◽  
Vol 28 (3) ◽  
pp. 301 ◽  
Author(s):  
MJ Hynes
Keyword(s):  
Nitrogen Source ◽  
Aspergillus Nidulans ◽  
Carbon Sources ◽  
Nitrogen Sources ◽  
Selection Methods ◽  
Growth Responses ◽  
Dominance Relationships ◽  
Regulatory Circuits ◽  
Specific Activities

Mutants of Apergillus nidulanswith lesions in a gene, areA (formerly called amdT), have been isolated by a variety of different selection methods. The areA mutants show a range of pleiotropic growth responses to a number of compounds as sole nitrogen sources, but are normal in utilization of carbon sources. The levels of two amidase enzymes as well as urease have been investigated in the mutants and have been shown to be affected by this gene. Most of the areA mutants have much lower amidase-specific activities when grown in ammonium-containing medium, compared with mycelium incubated in medium la9king a nitrogen source. Some of the areA. mutants do not show derepression of urease upon relief of ammonium repression. The dominance relationships of areA alleles have been investigated in� heterozygous diploids, and these studies lend support to the proposal that areA codes for a positively acting regulatory product. One of the new areA alleles is partially dominant to areA + and areA102. This may be a result of negative complementation or indicate that areA has an additional negative reiuIatory function. Investigation.of various amdR; areA double mutants has led to the conclusion that amdR and areA participate in independent regulatory circuits in the control of acetamide utilizatiol1. Studies on an amdRc; areA.double mutant indicate that areA is involved in derepression of acetamidase upon relief of ammo.nium repression.

scholarly journals Production characteristics of the diatom Cylindrotheca closterium (Ehrenb.) Reimann et Lewin grown in an intensive culture at various nitrogen sources in the medium

2019 ◽  
Vol 4 (1) ◽  
pp. 33-44 ◽  
Author(s):  
S. N. Zheleznova
Keyword(s):  
Stationary Phase ◽  
Nitrogen Source ◽  
Nutrient Medium ◽  
Maximum Yield ◽  
Nitrogen Sources ◽  
Dry Weight ◽  
Sole Source ◽  
Active Growth ◽  
Cylindrotheca Closterium ◽  
Production Characteristics

The diatom Cylindrotheca closterium (Ehrenberg) Reimann et Levin is characterized by high productivity (up to 1.5 g·l-1·day-1) and the ability to accumulate a valuable carotenoid fucoxanthin (up to 2 % of dry weight). In the development of biotechnology based on microalgae, the key issue is the creation of concentrated nutrient medium. Nitrogen is one of the most important components in the nutrient medium that significantly affects the production characteristics of all microalgae. The aim of this study is to compare the production characteristics of C. closterium in an intensive storage culture using different forms of nitrogen in the medium. In the first experiment, nitrate and sodium nitrite, urea, and nitrogen in the form of ammonium were used as a source of nitrogen. The amount of nitrates, nitrites, ammonium, and urea in the medium was calculated from the nitrogen content of the RS nutrient medium, with a nitrogen to phosphorus ratio of 15 : 1. In the second experiment, amino acids were used as a nitrogen source – arginine, asparagine, cysteine. The possibility of using the microalgae C. closterium for the growth of various organic sources of nitrogen (urea, cysteine, asparagine) was shown. Productive characteristics in the intensive storage culture of C. closterium using urea, cysteine, and asparagine as the sole source of nitrogen in the RS nutrient medium were determined. It is shown that when urea was used, the productivity reached its maximum values and amounted to 1.5 g·l-1·day-1. Thus, the expediency of using urea in the medium for obtaining the maximum yield of biomass was shown. The use of cysteine in the stationary phase of growth to achieve a long stationary phase with minimal concentrations of the nitrogen source in the nutrient medium is also advisable. It was found that C. closterium was able to grow and vegetate at sufficiently high concentrations of nitrite, and the addition of nitrogen in ammonium form to the nutrient medium during the active growth of C. closterium led to inhibition of all metabolic processes and to the death of the culture.

scholarly journals Purification of arginase from Aspergillus nidulans.

1994 ◽  
Vol 41 (4) ◽  
pp. 467-471 ◽  
Author(s):  
A Dzikowska ◽  
J P Le Caer ◽  
P Jonczyk ◽  
P Wëgleński
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Neurospora Crassa ◽  
Molecular Mass ◽  
Nitrogen Source ◽  
Aspergillus Nidulans ◽  
Sole Nitrogen Source ◽  
Mass Ratio ◽  
Conserved Domains ◽  
Native Molecular Mass ◽  
High Degree

Arginase (EC 3.5.3.1) of Aspergillus nidulans, the enzyme which enables the fungus to use arginine as the sole nitrogen source was purified to homogeneity. Molecular mass of the purified arginase subunit is 40 kDa and is similar to that reported for the Neurospora crassa (38.3 kDa) and Saccharomyces cerevisiae (39 kDa) enzymes. The native molecular mass of arginase is 125 kDa. The subunit/native molecular mass ratio suggests a trimeric form of the protein. The arginase protein was cleaved and partially sequenced. Two out of the six polypeptides sequenced show a high degree of homology to conserved domains in arginases from other species.

scholarly journals The effect of diverse nitrogen sources in the nutrient medium on the growth of the green microalgae Chromochloris zofingiensis in the batch culture

2019 ◽  
Vol 4 (4) ◽  
pp. 41-52 ◽  
Author(s):  
G. S. Minyuk ◽  
N. V. Dantsyuk ◽  
E. S. Chelebieva ◽  
I. N. Chubchikova ◽  
I. V. Drobetskaya ◽  
...  
Keyword(s):  
Nitrogen Source ◽  
Nutrient Medium ◽  
Nitrogen Sources ◽  
Dry Weight ◽  
Cell Swelling ◽  
Total Carotenoids ◽  
Chlorella Zofingiensis ◽  
N Sources ◽  
N Source ◽  
Chlorophylls A And B

The effect of three nitrogen (N) sources in the nutrient medium – sodium nitrate (NaNO3), urea (CO(NH2)2), and ammonium chloride (NH4Cl) – on the morphological and physiological characteristics of the green microalga Chromochloris (Chlorella) zofingiensis, a potential commercial producer of lipids and a ketocarotenoid astaxanthin, was studied. The alga was batch-cultivated in glass conical flasks from starting cell density (n) around 2.3·106 per mL and dry weight (DW) content of 0.06 g·L−1 in all variants at 120 μmol·m−2·s−1 PAR, +20…+21 °C, and air bubbling at a rate of 0.3 L·min−1·L−1. The concentration of nitrogen sources (as elemental N) in the modified BBM nutrient medium was 8.83 mmol·L−1, the cultivation duration was 17 days. The dynamics of n and cell volumes, DW content, chlorophylls a and b (Chla and Chlb), total carotenoids (Car), and lipids (Lip) in the cultures, concentration of N sources in the nutrient medium, and its pH were recorded. It was shown that the growth rate, size distribution of the cell populations, and the biomass chemical composition depended significantly on the nitrogen source in the nutrient medium. Using NH4Cl as N source caused on the second day growth inhibition, cell swelling, aggregation, and discoloration; by the seventh day, it caused culture crash. C. zofingiensis cells took up NaNO3 and CO(NH2)2 from the medium at a similar rate (0.626 and 0.631 mmol N·L−1·day−1, respectively), but the growth of the culture fed with CO(NH2)2 lagged; its cell volume and Chla, Chlb, and total Car contents declined profoundly. The average dry matter productivity (PDW) in the culture grown on CO(NH2)2 [(0.086 ± 0.004) g·L−1·day−1] was 32.6 % lower than in the culture grown on NaNO3 [(0.114 ± 0.005) g·L−1·day−1]. At the same time, lipid productivity (PLip) of the urea-fed culture was comparable with that of the nitrate-fed culture (PLip of 28 and 26 mg·L−1·day−1, respectively). The lipid DW percentage of the former exceeded significantly that of the nitrate-fed culture (31.6 % vs 23.1 %, respectively). From the standpoint of profitability, the lag in biomass accumulation recorded in the urea-fed culture on PDW is not critical since it is compensated by lowering the cost of nitrogen source for the nutrient medium (approximately by 230 %) and a higher biomass lipid content. C. zofingiensis grown in media with urea as the only N source deserves further investigation.

ISOLATION OF SEAWEED ASSOCIATED BACTERIA'S AND THEIR PRODUCTION OF BIOPOLYMER BY SOLID-STATE FERMENTATION

2021 ◽  
Vol 1 (7) ◽  
pp. 134-141
Author(s):  
Viswapriya B ◽  
Balamurugan V ◽  
Jayaprakash K
Keyword(s):  
Nitrogen Source ◽  
Plastic Material ◽  
Dry Weight ◽  
Peak Time ◽  
Biochemical Tests ◽  
Carbon And Nitrogen ◽  
Wide Range ◽  
Optimum Ph ◽  
Other Substances ◽  
Continuous Use

Plastic material is any of a wide range of synthetic or semi-synthetic organic solids that are moldable. Plastics are typically organic polymers of high molecular mass, but they often contain other substances. They are usually synthetic, most commonly derived from petrochemicals, but many are partially natural. Environmental pollution by the disposal of non-degradable conventional plastics is a fast-growing problem worldwide, especially in India. Nowadays, plastics are replacing by other constructional materials like glass, wood, metal in numerous applications. In this study, there has been considerable interest in the development and production of biodegradable polymer to solve the current problem of pollution caused by the continuous use of synthetic polymer from seaweed associated Bactria. . Based on the dry weight of total biopolymer content, the strain SBT 09 showed maximum accumulation and selected for optimizing at different pH, temperature, salinity, carbon, and nitrogen source and the peak time of PHB accumulation. Based on the biochemical tests, the strain SBT 09 was found.The optimum pH, temperature, and salinity were found to be 7, 300C, and 5%. The peak time of PHB accumulation was found to be 36hrs. The best carbon and nitrogen source was found to be sucrose and (NH4)2 HPO4. The selected strain was mass cultured using the optimized media and PHB was extracted by solvent extraction. Keywords: Marine Bacteria, PHB, Biosynthesis, Biopolymer.

scholarly journals Mechanisms Regulating Grain Contamination with Trichothecenes Translocated from the Stem Base of Wheat (Triticum aestivum) Infected with Fusarium culmorum

2013 ◽  
Vol 103 (7) ◽  
pp. 682-689 ◽  
Author(s):  
Mark Winter ◽  
Birger Koopmann ◽  
Katharina Döll ◽  
Petr Karlovsky ◽  
Ute Kropf ◽  
...  
Keyword(s):  
Crop Production ◽  
Fusarium Culmorum ◽  
Dry Weight ◽  
Effective Control ◽  
Uridine Diphosphate ◽  
Head Blight ◽  
Wheat Grains ◽  
Stem Base ◽  
Plant Parts ◽  
Major Interest

Factors limiting trichothecene contamination of mature wheat grains after Fusarium infection are of major interest in crop production. In addition to ear infection, systemic translocation of deoxynivalenol (DON) may contribute to mycotoxin levels in grains after stem base infection with toxigenic Fusarium spp. However, the exact and potential mechanisms regulating DON translocation into wheat grains from the plant base are still unknown. We analyzed two wheat cultivars differing in susceptibility to Fusarium head blight (FHB), which were infected at the stem base with Fusarium culmorum in climate chamber experiments. Fungal DNA was found only in the infected stem base tissue, whereas DON and its derivative, DON-3-glucoside (D3G), were detected in upper plant parts. Although infected stem bases contained more than 10,000 μg kg–1 dry weight (DW) of DON and mean levels of DON after translocation in the ear and husks reached 1,900 μg kg–1 DW, no DON or D3G was detectable in mature grains. D3G quantification revealed that DON detoxification took mainly place in the stem basis, where ≤50% of DON was metabolized into D3G. Enhanced expression of a gene putatively encoding a uridine diphosphate-glycosyltransferase (GenBank accession number FG985273) was observed in the stem base after infection with F. culmorum. Resistance to F. culmorum stem base infection, DON glycosylation in the stem base, and mycotoxin translocation were unrelated to cultivar resistance to FHB. Histological studies demonstrated that the vascular transport of DON labeled with fluorescein as a tracer from the peduncle to the grain was interrupted by a barrier zone at the interface between grain and rachilla, formerly described as “xylem discontinuity”. This is the first study to demonstrate the effective control of influx of systemically translocated fungal mycotoxins into grains at the rachilla–seed interface by the xylem discontinuity tissue in wheat ears.

scholarly journals Increasing lipid content from biomass of microalgae to produce biofuels with optimization of nitrogen source

2018 ◽  
Vol 197 ◽  
pp. 13011
Author(s):  
Istikhomah Putri Ayuwaningsih ◽  
Melati Ferianita Fachrul ◽  
Astri Rinanti
Keyword(s):  
Nitrogen Source ◽  
Lipid Content ◽  
Scenedesmus Obliquus ◽  
Gravimetric Method ◽  
Total Lipid Content ◽  
Dry Weight ◽  
Gas Chromatography Mass Spectrometry ◽  
Green Microalgae ◽  
Urea Fertilizer ◽  
Operational Conditions

The aim of this research is to analyze the effect of urea fertilizer as a nitrogen source to lipid productivity of mixed culture of green microalgae consisting of Monoraphidium sp., Chlorella sorokiniana, and Scenedesmus obliquus as lipid sources. In research, cultures were cultivated in a 1.5 L glass photobioreactor with batch culture system. The operational conditions of this research were carried out at pH 6.0, 27 °C, aeration with air flow 150 mL/sec, and 2400 lux with vary amount of urea as a source of nitrogen as much (grams) 0.0; 0.5; 1.0. The Bligh and Dyer extraction is performed to produce biofuels after harvesting process and to analyze lipid content. Analysis of fatty acids using Gas Chromatography Mass Spectrometry (GCMS) Method, analysis of dry weight using Gravimetric Method, and analysis of cell density using Spectrofotometry Method. This research concludes that with 0.5 grams of urea fertilizer can produce dry weight and total lipid content optimally that were 0.26% (w/w) and 36,35% (w/w). This research concludes that increasing amount of nitrogen source could be increasing green microalgae biomass but is not for increased lipid content. The high lipid content can be produced by decreasing 50% nitrogen source.

GROWTH OF CERATOCYSTIS ULMI (BUISMAN) C. MOREAU IN LIQUID CULTURE MEDIA

1961 ◽  
Vol 39 (5) ◽  
pp. 1087-1093 ◽  
Author(s):  
Camilien Gagnon
Keyword(s):  
Room Temperature ◽  
Liquid Culture ◽  
Culture Media ◽  
Dry Weight ◽  
Nitrogen Compounds ◽  
Liquid Media ◽  
Culture Filtrates

Ceratocystis ulmi (Buism.) C. Moreau was grown in liquid media with four different nitrogen compounds, eight sugars, and four concentrations of glucose. The fungus was grown at room temperature in the dark as still cultures, and in daylight as still and as shake cultures. The pH of the culture filtrates appeared to be dependent on the sugar used as the main source of carbon. The dry weight of the fungus fluctuated regularly with age. This is shown to be independent of the factors investigated and has been attributed to autolysis of the fungus. Implications of the findings are discussed.

scholarly journals Amino Acid Catabolism by an areA-Regulated Gene Encoding an l-Amino Acid Oxidase with Broad Substrate Specificity in Aspergillus nidulans

2005 ◽  
Vol 71 (7) ◽  
pp. 3551-3555 ◽  
Author(s):  
Meryl A. Davis ◽  
Marion C. Askin ◽  
Michael J. Hynes
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Substrate Specificity ◽  
Nitrogen Source ◽  
Aspergillus Nidulans ◽  
Nitrogen Sources ◽  
Acid Oxidase ◽  
Amino Acid Oxidase ◽  
Broad Substrate Specificity ◽  
Strong Growth

ABSTRACT The filamentous fungus Aspergillus nidulans can use a wide range of compounds as nitrogen sources. The synthesis of the various catabolic enzymes needed to breakdown these nitrogen sources is regulated by the areA gene, which encodes a GATA transcription factor required to activate gene expression under nitrogen-limiting conditions. The areA102 mutation results in pleiotropic effects on nitrogen source utilization, including better growth on certain amino acids as nitrogen sources. Mutations in the sarA gene were previously isolated as suppressors of the strong growth of an areA102 strain on l-histidine as a sole nitrogen source. We cloned the sarA gene by complementation of a sarA mutant and showed that it encodes an l-amino acid oxidase enzyme with broad substrate specificity. Elevated expression of this enzyme activity in an areA102 background accounts for the strong growth of these strains on amino acids that are substrates for this enzyme. Loss of function sarA mutations, which abolish the l-amino acid oxidase activity, reverse the areA102 phenotype. Growth tests with areA102 and sarA mutants show that this enzyme is the primary route of catabolism for some amino acids, while other amino acids are metabolized through alternative pathways that yield either ammonium or glutamate for growth.

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