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The isolation and identification of lipoproteins associated with fatty acid synthesis in Penicillium chrysogenumPierce, Robert R. January 1970 (has links)
Penicillium chrysogenum was investigated to determine whether there are lipoproteins specifically associated with fatty acid synthesis and in what fraction of P. chrysogenum they are located. Radio-activity labeled free fatty acids and CoA thioester substrates were added to cell-free extracts and incubated. Samples of these incubation mixtures were analyzed for lipoprotein content with electrophoresis and for the presence of radioactivity with a radiochromatogram scanner and scintillation spectrometer.Label from fatty acyl thioester substrates migrated with protein fractions having alpha-2 or beta mobility showing the existence of lipoproteins associated with fatty acid metabolism in cell-free extracts of P. chryogenum. The percent distribution of radioactivity from the thioester incubations supported previous work in this laboratory on the desaturase system and suggested the presence of a long chain fatty acyl-CoA-ACP synthetase enzyme in Penicillium chrysogeum.
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Carbon dioxide assimilation into organic acids by Penicillium chrysogenumLiberman, Samuel, January 1956 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1956. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 79-84).
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A kinetic study of fatty acid desaturation in penicillium chrysogenumChamberlin, Paul T. January 1971 (has links)
The effects of oxygen, malonate, and acetate on the conversion of radioactively-labeled Coenzyme A thioesters of lauric and stearic acids to unsaturated fatty acids by 15,000 x g supernates of Penicilliumlehrysogenum were studied. Following the termination of reactions, the incubation products were saponified, acidified, extracted, and methylated. The resulting methyl esters were purified, separated, identified, and collected. Radioactivities of each fatty acid fraction were determined and converted to percentage of total radioactivity recovered.Desaturase activity was virtually non-existent in the anaerobic incubations indicating that this organism utilized the aerobic pathway of desaturation. The absence of acetate and malonate from incubation mixtures of either laurate or stearate markedly decreased the overall desaturase activity and the amount of linoleate produced. The failure of labeled laurate to be converted to long-chain unsaturated fatty acids in the absence of malonate indicates that chainelongation in this organism proceeds by the malonate pathway. The data presented suggest that laurate may be directly desaturated and then elongated to oleate instead of following the typical aerobic pathway. / Department of Biology
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The fatty acid desaturase system of Penicillium chrysogenumMills, Verne M. 03 June 2011 (has links)
The conversion of stearic acid and lauric acid to unsaturated fatty acids by the desaturase system of Penicillium chrysogenum was investigated by incubating cell free fractions prepared from mycelial sonicates with the radioactively labeled fatty acids and analyzing the reaction products. In some experiments exogenous acyl carrier protein (ACP) or coenzyme A (Co.A) was added to the incubation mixtures. The percentage of radioactive label appearing in unsaturated fractions was regarded as a measure of the activity of the desaturase system.Desaturase activity was detected in both the 15,000 x g particulate and supernatant fractions. Only small percentages of 1-14C-stearyl-CoA were converted to unsaturated fatty acids; 1-14Clauryl-CoA was apparently more readily desaturated. The desaturase system was found to be inhibited by exogenous ACP, but not by exogenous CoA. This suggested that the fatty aryl-CoA thioesters were converted to thioesters of ACP prior to desaturation.Ball State UniversityMuncie, IN 47306
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Transposonen und Regulation der Genexpression bei den Antibiotika-produzierenden Pilzen Penicillium chrysogenum und Acremonium chrysogenum /Hauck, Katarzyna. January 2002 (has links)
Diss.--Universität Bochum. / Bibliogr. p. 100-118.
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Isolation and characterization of genes from beta-lactam antibiotic producing organismsCarr, Lucinda Gayle January 1986 (has links)
This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department (rlmlill@iu.edu).
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Characterization of penicillin production by an immobilized biofilm of Penicillium chrysogenumDaly, Mary Margaret January 1984 (has links)
A stable biofilm of Penicillium chrysogenum in a slab geometry was characterized with respect to penicillin production at various sugar and oxygen concentrations by studies using a novel bench scale bioreactor. The biofilm was submerged in aerated liquid media, mounted vertically in a tube and oriented so that the liquid media and sparged gas bubbles flow uniformly over the two slab faces. The conditions necessary for definite oxygen and sugar limitations were found by operating under various bulk nutrient concentrations. The periodic determination of total biofilm volume (rate of growth) and dry cell weight provided additional information. Definite oxygen mass transfer limitations were found to exist in the biofilm. These limitations could be overcome by increasing the oxygen supply rate to the biofilm. / Master of Science
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Xilanase de Penicillium chrysogenum: produção em um resíduo agroindustrial, purificação e propriedades bioquímicasTerrone, Carol Cabral [UNESP] 13 June 2013 (has links) (PDF)
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terrone_cc_me_rcla.pdf: 584857 bytes, checksum: 408998a4825fecaa42568d1c9e8cc2a3 (MD5) / Neste trabalho, uma linhagem de Penicillium chrysogenum foi utilizada para produzir xilanases utilizando um resíduo agroindustrial como substrato. O principal objetivo foi melhorar a produção da xilanase, verificando a influência de diferentes substratos, agitação, pH e temperatura de cultivo. A linhagem foi cultivada em meio líquido de Vogel suplementado com diversos substratos puros como a xilose, glicose, xilano de aveia, Avicel e carboximetilcelulose (CMC), e complexos como farelo de trigo, farelo de aveia, bagaço de cana-de-açúcar, bagaço de cevada, casca de laranja e sabugo de milho. Testes granulométricos com bagaço de cana-de-açúcar e bagaço de cevada foram realizados para avaliar a influência dessa característica sobre a produção de xilanase. A melhor produção foi obtida com bagaço de cana-de-açúcar a 1% (m/v) com granulometria entre 2-1 mm. Nos ensaios cinéticos a melhor produção foi obtida em cultivos estáticos, por 8 dias, sendo produzida quantidade duas vezes maior de enzima do que em cultivos agitados. O melhor pH de cultivo para a produção de xilanases foi de 5,0 e a temperatura de 20 ºC. A enzima foi purificada por uma estratégia de duas etapas, sendo uma cromatografia de troca iônica e outra de filtração em gel, apresentando ao final uma recuperação de 18,8% com um fator de purificação de 24,9. As propriedades da enzima bruta e da purificada foram pH ótimo de 6,0 e 6,5, respectivamente, e a temperatura ótima para ambas de foi a 45 ºC. As meias vidas a 40, 45, 50, 55 e 60 ºC, para a xilanase bruta foram de 37, 28, 16, 2, e 1 minuto e para a xilanase purificada foram de 35, 31, 10, 3 e 2 minutos, respectivamente. A maior estabilidade ao pH da enzima bruta ocorreu em pH 6,0 e também se mostrou estável na região alcalina, entre 8,0 e 10,0; já a enzima purificada apresentou maior estabilidade na... / In this work, a strain of Penicillium chrysogenum has been used to produce xylanases using agroindustrial waste as substrate. The main objective was to improve the production of xylanase, by checking the influence of substrate, agitation, pH and temperature of cultivation. The strain was cultivated in liquid Vogel’s medium supplemented with various substrates as pure xylose, glucose, oat xylan, Avicel and carboxymethylcelullose (CMC), and complexes such as wheat bran, oat bran, sugar cane bagasse, brewers spent grain, orange peel and corncob. Granulometric tests with crushed sugar cane bagasse and brewers spent grain were conducted to evaluate the influence of this characteristic on production of xylanase. The best production was obtained with crushed sugar cane bagasse to 1% (w/v) with particle size between 2-1 mm. In kinetic experiments, the best production was obtained in static cultivation for 8 days, which is produced twice as much enzyme in agitated cultures. The bets pH cultivation for the production of xylanase was pH 5.0 and temperature of 20 °C. The enzyme was purified by a two-step strategy, being a ion exchange chromatography and a gel filtration, presenting the ultimate recovery of 18,8% with a purification factor of 24,9. The properties of the crude enzyme and purified were optimum pH of 6,0 and pH 6.5, respectively, and the temperature was great for both of 45 ºC. The half of 40, 45, 50, 55 and 60 ° C for xylanase crude were 37, 28, 16, 2, 1 minutes and for the xylanase purified were 35, 31, 10, 3 and 2 minutes, respectively. The increased stability at the pH of the crude enzyme was at pH 6,0 and also stable in the alkaline region, between 8.0 and 10.0, whereas the purified enzyme was most stable in the range of 4.5 to 10.0. The xylanase activity present in crude filtrate and purified enzyme, suffered inhibition... (Complete abstract click electronic access below)
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Xilanase de Penicillium chrysogenum : produção em um resíduo agroindustrial, purificação e propriedades bioquímicas /Terrone, Carol Cabral. January 2013 (has links)
Orientador: Eleonora Cano Carmona / Banca: Hamilton Cabral / Banca: Márcia Regina Brochetto / Resumo: Neste trabalho, uma linhagem de Penicillium chrysogenum foi utilizada para produzir xilanases utilizando um resíduo agroindustrial como substrato. O principal objetivo foi melhorar a produção da xilanase, verificando a influência de diferentes substratos, agitação, pH e temperatura de cultivo. A linhagem foi cultivada em meio líquido de Vogel suplementado com diversos substratos puros como a xilose, glicose, xilano de aveia, Avicel e carboximetilcelulose (CMC), e complexos como farelo de trigo, farelo de aveia, bagaço de cana-de-açúcar, bagaço de cevada, casca de laranja e sabugo de milho. Testes granulométricos com bagaço de cana-de-açúcar e bagaço de cevada foram realizados para avaliar a influência dessa característica sobre a produção de xilanase. A melhor produção foi obtida com bagaço de cana-de-açúcar a 1% (m/v) com granulometria entre 2-1 mm. Nos ensaios cinéticos a melhor produção foi obtida em cultivos estáticos, por 8 dias, sendo produzida quantidade duas vezes maior de enzima do que em cultivos agitados. O melhor pH de cultivo para a produção de xilanases foi de 5,0 e a temperatura de 20 ºC. A enzima foi purificada por uma estratégia de duas etapas, sendo uma cromatografia de troca iônica e outra de filtração em gel, apresentando ao final uma recuperação de 18,8% com um fator de purificação de 24,9. As propriedades da enzima bruta e da purificada foram pH ótimo de 6,0 e 6,5, respectivamente, e a temperatura ótima para ambas de foi a 45 ºC. As meias vidas a 40, 45, 50, 55 e 60 ºC, para a xilanase bruta foram de 37, 28, 16, 2, e 1 minuto e para a xilanase purificada foram de 35, 31, 10, 3 e 2 minutos, respectivamente. A maior estabilidade ao pH da enzima bruta ocorreu em pH 6,0 e também se mostrou estável na região alcalina, entre 8,0 e 10,0; já a enzima purificada apresentou maior estabilidade na... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, a strain of Penicillium chrysogenum has been used to produce xylanases using agroindustrial waste as substrate. The main objective was to improve the production of xylanase, by checking the influence of substrate, agitation, pH and temperature of cultivation. The strain was cultivated in liquid Vogel's medium supplemented with various substrates as pure xylose, glucose, oat xylan, Avicel and carboxymethylcelullose (CMC), and complexes such as wheat bran, oat bran, sugar cane bagasse, brewers spent grain, orange peel and corncob. Granulometric tests with crushed sugar cane bagasse and brewers spent grain were conducted to evaluate the influence of this characteristic on production of xylanase. The best production was obtained with crushed sugar cane bagasse to 1% (w/v) with particle size between 2-1 mm. In kinetic experiments, the best production was obtained in static cultivation for 8 days, which is produced twice as much enzyme in agitated cultures. The bets pH cultivation for the production of xylanase was pH 5.0 and temperature of 20 °C. The enzyme was purified by a two-step strategy, being a ion exchange chromatography and a gel filtration, presenting the ultimate recovery of 18,8% with a purification factor of 24,9. The properties of the crude enzyme and purified were optimum pH of 6,0 and pH 6.5, respectively, and the temperature was great for both of 45 ºC. The half of 40, 45, 50, 55 and 60 ° C for xylanase crude were 37, 28, 16, 2, 1 minutes and for the xylanase purified were 35, 31, 10, 3 and 2 minutes, respectively. The increased stability at the pH of the crude enzyme was at pH 6,0 and also stable in the alkaline region, between 8.0 and 10.0, whereas the purified enzyme was most stable in the range of 4.5 to 10.0. The xylanase activity present in crude filtrate and purified enzyme, suffered inhibition... (Complete abstract click electronic access below) / Mestre
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Bioleaching Potential of Filamentous Fungi to Mobilize Lithium and Cobalt from Spent Rechargeable Li-Ion BatteriesLobos, Aldo 03 November 2017 (has links)
Demand for lithium (Li) and cobalt (Co) is on the rise, due in part to their increased use in rechargeable Li-ion batteries (RLIB). Current recycling processes that utilize chemical leaching efficiently recover in Li and Co from the cathode material in spent batteries; however, these processes are costly and emit hazardous waste into the environment. Therefore, a more sustainable process for recycling Li and Co is needed, and bioleaching may provide a solution. Fungal bioleaching has been shown in previous studies to effectively mobilize metals (Pb, Al, Mn, Cu, and Zn) from mine tailings, electronic scrap, and spent batteries with organic acids. However, little is known regarding fungal tolerance to Li and Co, and if the concentrations of organic acids excreted by fungi can effectively leach Li and Co from the cathode material.
In order to address these questions, experiments were first conducted to test the Li and Co leaching efficiency with organic acids at concentrations similar to what has been previously reported in fungal cultures. The remaining experiments were performed with three fungal species: Aspergillus niger, Penicillium chrysogenum, and Penicillium simplicissimum. First, fungal biomass production, pH and organic acid excretion were examined when the fungi were grown in Czapek dox broth (CDB) or Sabouraud dextrose broth (SDB). Second, fungal biomass production and pH were examined when the fungi were grown in the presence of Li or Co. This determines tolerance of the fungi to the metals, and if fungal processes were inhibited by the metals. Third, bioleaching was performed with cathode material from RLIB in batch cultures to test the ability of organic acids excreted by A. niger to mobilize Li and Co. Three bioleaching strategies, one-step, two-step, and spent-medium leaching techniques were used to mobilize Li and Co from the cathode in RLIB.
Low concentrations of organic acids similar to what is excreted by fungi have not been tested to leach Li and Co from the cathode in RLIB. Results from chemical leaching with low concentrations of organic acids in this study indicate that organic acid leaching efficiency can be increased by utilizing higher concentrations (above 50 mM) of citric or oxalic acid to mobilize Li or Co from the cathode in RLIB. Furthermore, 100 mM of citric acid or 100 mM of oxalic acid mobilized more Co or Li than mixtures of organic acids. Notably the addition of hydrogen peroxide to mixed concentrations of organic acids significantly improved mobilization of Li and Co under abiotic conditions.
Different growth media may alter biomass production and potentially organic acid excretion by the three fungal species. Analysis of biomass production by A. niger and P. simplicissimum showed that differences in media composition between CDB and SDB did not affect collected biomass for each species. However, CDB cultures with P. chrysogenum had significantly less biomass than SDB cultures after 10 days of growth. Differences in growth by P. chrysogenum between CDB and SDB may be attributed to preferred nutrients and/or low pH present in SDB cultures. Biomass production by the three fungi increased up to day 10 in CDB or SDB. This result indicated that nutrients in CDB or SDB were not limiting toward fungal growth. Cultures with A. niger had the highest concentrations of organic acids (50 mM of oxalic acid), followed by cultures with P. simplicissimum (30 mM oxalic acid), and P. chrysogenum (less than 5 mM oxalic acid). Organic acids excreted by all three fungal species were detected in cultures in CDB, while only A. niger and P. chrysogenum excreted organic acids in SDB cultures.
Metals such a Li or Co present in the cathode of RLIB may be toxic to fungal processes when exposed to high metal concentrations. Metal tolerance experiments indicate that biomass production by the three fungi was significantly inhibited by 100 mg/L Co compared to controls, which contained no metal. Li at a concentration of 1000 mg/L inhibited biomass production by A. niger and P. simplicissimum. However, biomass production by P. chrysogenum was not significantly inhibited by 1000 mg/L Li. I found that P. simplicissimum was the most susceptible to toxic effects of Li and Co among the three fungi. In A. niger cultures amended with 100 mg/L Li or Co, pH at day 5 was similar to control cultures of A. niger without metals (pH 3.0 – 3.4), whereas pH was significantly higher in cultures with 1000 mg/L of Li or Co (pH 7.1 – 7.3).
Cultures of A. niger were exposed to the cathode material from RLIB to test the leaching efficiency of excreted organic acids after mobilizing Li and Co. In bioleaching experiments with A. niger, organic acids excreted in the presence of cathode material from RLIB were quantified at concentrations under 50 mM. At the end of bioleaching experiments with A. niger, 40 mM tartaric acid was detected and was the highest produced organic acid in bioleaching cultures. However, with conditions set in this study, organic acids excreted by A. niger mobilized only ̴7% of Co and 20% of Li when using spent medium with cathode material from RLIB. According to findings in chemical leaching experiments, concentrations of organic acids higher than 50 mM will be required in fungal cultures to increase mobilization of Li or Co from the cathode material in RLIB. Modifying growth media to include higher concentrations of sucrose will potentially increase organic acid excretion as demonstrated in previous publications. Future studies should focus on how to maximize organic acid excretion by fungi when exposed to metals found in the cathode of RLIB.
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