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A comparison of some physiological properties of Bacillus cereus 569R with a mutant strainBrantner, Carol Jeanne 18 December 1969 (has links)
The purpose of this investigation was to compare some of the
properties of a spore-forming mutant of Bacillus cereus 569R with
the wild type. The strains were grown under identical conditions in
liquid medium. The mutant, strain 45, was characterized with
respect to growth rate, pH changes in the medium, morphological
development, cell density during the growth cycle, the effect of
oxygen deprivation on the time of spore formation, and the production
of an extracellular protease.
Strain 45 was found to maintain a higher growth rate than 569R.
The pH curves indicated that, in time, strain 45 was about 30 minutes
ahead of wild type. Morphologically, strain 45 exhibited no long chain
stage characteristic of early logarithmic growth B. cereus 569R.
Poly β hydroxybutyrate was accumulated before the sharp rise in pH
in 45. This comparatively early synthesis suggested that acetate
utilization and polymer synthesis may not be coordinately controlled
in this mutant. Spore formation occurred two and one-half hours
earlier in strain 45, and the spores were twice as large as spores of
wild type. The production of protease in the mutant occurred earlier,
and in higher concentration when compared with 569R.
The results of these experiments fell into two classes. The
first class included growth rate, pH, and cell density shifts. These
events occurred approximately one-half hour earlier in cultures of
strain 45, and appeared to be correlated with the cell mass. The
second class of results--the time of polymer synthesis, the period
when the time of sporulation was sensitive to oxygen, the time of
protease production, and the time of sporulation- - appeared to be
independent of cell mass, and occurred markedly earlier in strain
45. The very early appearance of these sporulation- related events
in the culture cycle suggested that the mutant strain 45 may be
catabolically derepressed for sporulation. Characterization of two
asporogenous mutants of B. cereus 569R was also undertaken. / Graduation date: 1970
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Biological studies with special reference to the influence of certain organic compounds on the growth of Mycobacterium tuberculosis in vitroSchwangart, Wolfe Michael January 1936 (has links)
[No abstract available] / Science, Faculty of / Microbiology and Immunology, Department of / Graduate
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The detection and control of Bacillus endosporesHelfinstine, Shannon L. January 2007 (has links)
Thesis (Ph.D.)--Kent State University, 2007. / Title from PDF t.p. (viewed Nov. 21, 2007). Advisor: Christopher J. Woolverton. Keywords: Bacillus, spores, electron beam irradiation, anthrax, liquid crystals, detection. Includes bibliographical references.
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Produção, caracterização e aplicação de proteases de Bacillus sp. = Production, characterization and application of proteases from Bacillus sp. / Production, characterization and application of proteases from Bacillus sp.Contesini, Fabiano Jares 26 August 2018 (has links)
Orientador: Hélia Harumi Sato / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-26T00:05:53Z (GMT). No. of bitstreams: 1
Contesini_FabianoJares_D.pdf: 2309946 bytes, checksum: 15f6069e97515a200deb29e0577eee62 (MD5)
Previous issue date: 2014 / Resumo: Proteases bacterianas são enzimas de elevada importância comercial, amplamente aplicadas em diversas áreas como nas indústrias de detergentes, de alimentos, farmacêutica e têxtil. Este trabalho teve como principais objetivos selecionar entre 59 linhagens de Bacillus sp., da coleção de culturas do Laboratório de Bioquímica de Alimentos da FEA, aquelas que apresentam potencial de maior produção de proteases com características tais como estabilidade em diferentes condições de temperatura, pH, detergentes e solventes orgânicos, atividade em ampla faixa de pH e capacidade de lisar células de Xanthomonas campestris. Em seguida, visou-se otimizar a produção de proteases pela linhagem selecionada, determinar as características bioquímicas da protease parcialmente purificada e estudar a aplicação do extrato enzimático bruto e preparação parcialmente purificada. Entre as cinquenta e nove linhagens de Bacillus sp. testadas foram selecionadas nove linhagens que produziram maior atividade de proteases. A produção de protease pelas nove linhagens foi testada em frascos agitados contendo o meio de cultura nº 1 (10g/L de caseína, 1g/L de extrato de levedura e sais), meio nº 2 (35 g/L de melaço de cana de açúcar, 20g/L de água de maceração de milho, 3g/L de extrato de levedura Prodex-Lac SD® e 20g/L de soro de queijo), e por fermentação em meio sólido nº 3 (farelo de trigo e água, na proporção 1:1, m:m). As linhagens de Bacillus sp. LBA 07, Bacillus sp. LBA 46 e Bacillus sp. LBA 08 fermentadas nos meios de cultura nº 1, nº 2 e nº 3 produziram 222 U/mL, 548 U/mL e 13480 U/grama de substrato seco (gss) respectivamente. As proteases dos extratos enzimáticos brutos obtidos das nove linhagens fermentadas nos três meios de cultura apresentaram atividade ótima na faixa de pH 7 a 9 e 60° C, estabilidade na faixa de pH 5 a 9 por 24h a 4º C , e após 1 h de tratamento a 50° C. Entre os extratos enzimáticos brutos de proteases testados, aqueles obtidas da fermentação de Bacillus sp. LBA 46 nos três meios de cultura foram as mais estáveis em detergente Ariel®. Quando incubadas em solventes orgânicos alguns extratos enzimáticos brutos proteases mantiveram mais de 60% de atividade residual após 24h em acetona (Bacillus sp. LBA 8 e 44), hexano (Bacillus sp. LBA 19, 29, 44, 46 e 60), clorofórmio (Bacillus sp. LBA 44 and 60) e etanol (Bacillus sp. LBA 60). Os extratos enzimáticos brutos de proteases obtidos do cultivo da linhagem de Bacillus sp. LBA 46 nos meios n° 2 e n° 3 foram as mais eficientes na lise de células de Xanthomonas campestris, aumentando cerca de 30% a transmitância a 620 nm (Trans 620nm) do meio fermentado de goma xantana. A linhagem de Bacillus sp. LBA 46 foi selecionada como melhor produtora de protease e estudos preliminares de identificação biomolecular indicam que se trata de uma linhagem de Bacillus licheniformis. Utilizando-se a linhagem de Bacillus sp LBA 46 e o meio de cultura otimizado (meio n° 4) por metodologia de superfície de resposta (MSR), composto de 40g/L de melaço de cana de açúcar, 6g/L de água de maceração de milho, 2g/L de extrato de levedura Prodex-Lac SD® e 20g/L de soro de queijo, foi obtido 3000 U/mL de protease após 96h de fermentação a 30° C e 200 rpm. No estudo da aplicação da enzima para a remoção de manchas de tecidos de algodão foram obtidos melhores resultados de remoção de manchas de sangue e molho de tomate com carne moída, utilizando-se a combinação de extrato bruto de protease (100 ou 1000U) com o detergente Omo®. O extrato enzimático bruto da linhagem de Bacillus sp. LBA 46 foi parcialmente purificado por fracionamento com sulfato de amônio (80% de saturação), diálise e cromatografia de filtração em gel (Sephadex G100), resultando em fator de purificação de 3,69. Após caracterização com MSR observou-se que a protease da preparação parcialmente purificada apresentou atividade ótima a 55° C e pH 7,5 e considerável estabilidade (95% de atividade residual) na faixa de pH 5,7 ¿ 9,3 após 1h de incubação a 30 ¿ 36° C, e acima de 78,9% quando incubadas por 1h em pH 7,5 e 50° C. A condição ótima de lise das células de X. campestris do meio fermentado de goma xantana utilizando-se o extrato enzimático bruto de protease e a preparação parcialmente purificada de proteases, foi observada utilizando 42 U de protease /mL de suspensão celular de X. campestris a 60° C, resultando em aumento de mais de 20% da Trans 620nm do meio fermentado de goma xantana. Um aumento de quase 40% de Trans 600nm foi observado após 2h de reação utilizando extrato enzimático bruto de protease (42 U de protease/mL de suspensão celular de X. campestris) a 65° C. A produção de proteases de Bacillus sp. LBA 46 por fermentação em estado sólido foi otimizada utilizando MSR, sendo obtido 5000 U/grama de substrato seco utilizando-se meio de cultura composto de farelo de trigo e água (60%:40%) após 96h de fermentação a 30° C / Abstract: Proteases are commercially relevant enzymes widely applied in several industrial areas, such as in detergent, food, pharmaceutical and textile industries. Proteases from Bacillus sp. can present advantages compared to the proteases from other sources, including better thermostability, stability in pH range from slightly acid to alkaline pH values and stability in organic solvents. The aims of this work were selecting Bacillus sp. strains with capability of producing proteases with better biochemical properties, such as stability in different conditions of temperature, pH, detergents and organic solvents, activity in a wide range of pH and capability of lysing cells of Xanthomonas campestris. Afterwards, it was aimed the optimization of the production of proteases by the selected Bacillus sp. strain and the determination of the biochemical characteristics of the partially purified protease and the application of the crude and partially purified protease. Nine Bacillus sp. strains were selected as the best protease producers among fifty nine Bacillus sp. strains tested. The protease production by the nine strains was carried out in Erlenmeyer flasks containing medium no. 1 (10g /L of casein, 1g/L of yeast extract and salts), medium no. 2 (35 g/L of sugar cane molasses, 20g/L corn steep liquor, 3g/L of yeast extract Prodex-Lac SD® and 20g/L of dried whey), e by fermentation using solid substrate medium no. 3 (wheat bran and water, 1:1, m:m). The strains Bacillus sp. LBA 07, Bacillus sp. LBA 46 and Bacillus sp. LBA 08 when fermented in medium no. 1, no. 2 e no. 3 produced 222 U/mL, 545 U/mL and 13480 U/gram of dried substrate (gds) respectively. Proteases from the crude enzymatic extracts obtained from the fermentation of the nine Bacillus sp. strains in the three media showed optimal activity in pH range 7-9 and 60° C, stability in pH range 5-9 for 24 hours at 4° C and after 1h at 50° C. The protease preparations from the fermentation of Bacillus sp. LBA 46 in the three media were the most stable when incubated in detergent Ariel®, among the proteases tested from the Bacillus sp. strains. In addition, some proteases presented more than 60% residual activity after 24h in the organic solvents acetone (Bacillus sp. LBA 8 and 44), hexane (Bacillus sp. LBA 19, 29, 44, 46 and 60), chloroform (Bacillus sp. LBA 44 and 60) and ethanol (Bacillus sp. LBA 60). The protease preparations obtained from the cultivation of Bacillus sp. LBA 46 in medium no. 2 and no. 3 presented the best results on the lysis of Xanthomonas campestris cells, resulting in an increase of approximately 30% in transmittance at 620 nm (Trans 620nm) of the fermented broth of xanthan. Bacillus sp. LBA 46 strain was selected as the best protease producer and after preliminary biomolecular analysis of identification, the results indicate that this microorganism correspond to a Bacillus licheniformis strain. Protease preparation containing 3000 U/mL was obtained from Bacillus sp. LBA 46 cultivated in Erlenmeyer flasks containing medium no. 4 composed of 40g/L of sugar cane molasses, 6g/L of corn steep liquor, 2g/L of yeast extract Prodex-Lac SD® and 20 g/L of dried whey after 96h of fermentation at 30° C and 200 rpm, optimized with response surface methodology (RSM). In the the washing tests, the best results of the removal of blood and tomato sauce with ground beef stains from cotton fabrics were observed using the combination of crude extract of protease (100 or 1000U) with detergent Omo®. Crude protease extract of the Bacillus sp. LBA strain was partially purified by ammonium sulfate fractionation (80% saturation), dialysis and gel filtration chromatography (Sephadex G100), resulting in the purification fold of 3.69. After characterization with RSM it was observed that the crude protease extract and partially purified proteases presented optimal activity at 55° C and pH 7.5 and considerable stability (95% of residual activity) in pH range 5.7 ¿ 9.3 after 1h incubation at 30-36° C and more than 78.9% when incubated at pH 7.5 and 50 °C for 1h. The optimal conditions of the lysis of X. campestris cells contained in the fermentation broth using crude and partially purified protease preparations were observed using 42 U of protease/mL of cell suspension of X. campestris at 60° C, resulting in a increase of more than 20% in Trans 620 nm of the fermented broth of xanthan. It was observed an increase of almost 40% in Trans 620 nm after 2h reaction using crude protease (42 U de protease/mL of cell suspension of X. campestris) at 65° C. The production of proteases by Bacillus sp. LBA 46 under solid state fermentation was optimized using RSM, resulting in 5000 U/gram of dry substrate utilizing wheat bran and water (6g:4g) after 96h of fermentation at 30° C / Doutorado / Ciência de Alimentos / Doutor em Ciência de Alimentos
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Effects of concanavalin A on certain physiological aspects on Bacillus species.January 1981 (has links)
by Tat-ming Lau. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1981. / Bibliography: leaves 288-329.
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Production and characterization of [beta]-amylase from Bacillus circulans.January 1988 (has links)
by Kam-hing So. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1988. / Bibliography: leaves 152-162.
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Chemistry of antibiotics from Atlantic actinomycete and bacillus bacteria /Socha, Aaron Martin. January 2008 (has links)
Thesis (Ph.D.) -- University of Rhode Island, 2008. / Typescript. Includes bibliographical references (leaves 335-353).
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Studies On Alkaline Protease Production From Bacillus Sp./Gençkal, Hande. Tarı, Canan January 2004 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2004. / Includes bibliographical references (leaves. 70-77).
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Revertants of a streptomycin-resistant, oligosporogenous mutant of Bacillus subtilisHenkin, Tina Marilyn. January 1984 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographies.
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Studies on nitrogen fixation by species of BacillusWitz, Dennis Fredrick. January 1964 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1964. / eContent provider-neutral record in process. Description based on print version record. Bibliography: l. 73-78.
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