Presented as Thesis (Ph. D.)--University of Wisconsin--Madison, 1932. / Cover title. Reprinted from Journal of agricultural research, vol. 47, no. 10 (15 Nov. 1933). Includes bibliographical references (leaves 769-770).

Thesis (M.S.)--University of Wisconsin--Madison, 1969. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Universiẗat, Diss., 2003--Marburg.

Orientador: Helia Harumi Sato / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-01T08:36:32Z (GMT). No. of bitstreams: 1 Moraes_AnaLuciaLeite_D.pdf: 25274441 bytes, checksum: 35ef9139b75b39706cbd5127858861e0 (MD5) Previous issue date: 2002 / Resumo: A isomaltulose (6-0-a.-D-glicopiranosil-D-fTutofuranose)é um dissacarideo redutor, isômero estrutural da sacarose, encontrado naturalmente no mel e no caldo de cana-deaçúcar. Devido ao baixo potencial cariogênico, a isomaltulose é utilizada comercialmente na produção de doces e gomas de mascar. A isomaltulose é também empregada na produção de isomalte, um açúcar-álcool, de baixo valor calórico, baixa cariogenicidade e baixa higroscopicidade, utilizado em produtos dietéticos e formulações farmacêuticas. As linhagens Erwinia sp D12, Klebsiella sp 8390, K/ebsiel/a sp K18 e 265-9 foram comparadas quanto a sua capacidade de produzir a enzima glicosiltransferase capaz de converter sacarose em isomaltulose. A linhagem Erwinia sp D12 apresentou a maior produção de glicosiltransferase. Esta linhagem foi submetida a tratamento com radiação ultravioleta e metil-N-nitroso-guanidina (MNNG), para indução de mutantes. Os mutantes obtidos não apresentaram maior atividade de glicosiltransferase que a cepa original...Observação: O resumo, na integra, podera ser visualizado no texto completo da tese digital / Abstract: Isomaltulose (6-0-a-D-glucopyranosyl-D-fiuctofuranose) lS a reducing disaccharide, structural isomer of sucrose, naturally found in honey and sugar cane juice. Due to its low cariogenic potential, isomaltulose is commerciallyused to produce candies and chewing gums. Isomaltulose is also used to produce isomalt, a sugar alcohol characterized by its low caloric value, low cariogenicity and low hygroscopicity, applied to dietetic products and pharmaceutical formulations. The strains Erwinia sp D12, Klebsiella sp 8390, Klebsiella sp K18 and 265 were compared in terms of their ability to produce a glucosyltransferase capable to convert sucrose into isomaltulose. Erwinia sp D12 presented the highest glucosyltransferase production. This strain was submitted to a treatment includingultraviolet radiation and Nmethyl- N-nitro-N-nitrosoguanidine (MNNG) in order to induce mutations. The glucosyltransferase activity of the mutants were not higher than the original strain...Note: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Doutor em Ciência de Alimentos

Factors affecting a double antibody sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of Erwinia carotovora subsp. atroseptica were investigated. Optimum reaction conditions for detecting known cell numbers of Eca were found to be 2.μg/ml of coating γ-globulin and 1:4-00 enzyme-γ-globulin conjugate dilution. These conditions were determined using antiserum produced against glutaraldehyde-fixed, whole bacterial cells of strain E82 of Eca (serogroup I), and polystyrene microtitration plates (Dynatech substrate plates). In spite of these optimized conditions, variability was observed between sets of data obtained under identical experimental conditions. In order to minimize or eliminate this variability, different parameters were investigated. The washing procedure was standardized by the use of a controlled pressure-washing system employing distilled water, and two 15-sec washes at 34.4-8 kPa (5 psi), with 180° rotation of the plate between each wash. Tween-20 was eliminated from the washing solution, since it interferred with the sensitivity of the assay. This effect could not be related to the age of the Tween-20 employed. Well to well variability was observed with the polystyrene microtitration plates employed but it was not exclusive to the outside rows. The pattern of distribution of the "odd" wells within a plate changed, and the number of "odd" wells decreased with time. The maximum variation from the mean also decreased with time. Addition to different wells of an extra 5% of coating y-globulin, sample, and enzyme-y-globulin conjugate individually or in different combinations, failed to reproduce the variability observed thereby eliminating pipetting errors as a source of variability. The A[sub=+.05] values were influenced by the buffer solutions employed for sample and conjugate dilution. Any given buffer had a greater effect when used for conjugate dilution. The complete buffer of phosphate buffered saline (PBS)+ 0.05% Tween-20 +2.0% polyvinylpyrrolidone+0.2% egg albumin commonly used in virus work, was found to be suitable for the Eca system although its efficiency in the presence of plant material containing bacteria remains to be evaluated. This ELISA for Eca employing optimized coating and conjugate, a standardized washing procedure and a complete buffer for samples and conjugate dilution, routinely detected 10⁵ to 10⁶ cells/ml of only serogroup I of Eca when pure cultures of both homologous and heterologous strains were tested. At concentrations >10⁷ cells/ml, strains from serogroups XVIII, XX, and XXII of subsp. atroseptica and a few strains from serogroups II, III, IV, and V of subsp. carotovora also reacted. Even at high bacterial concentration (10° cells/ml) no cross reactions were observed with Pseudomonas marginalis and Corynebacterium sepedonicum. Heat treatment of cell suspensions of serogroup I at 60 C for 3-6 min enhanced A[sub=+.05] values but the level of sensitivity was not reduced below 105 cells/ml. Cross reactions with strains of subsp. caro- tovora serogroups III and V, observed at 10 cells/ml, were reduced but not eliminated by this heat treatment. Both heat-labile and heat-stable water-soluble antigens were detected by this ELISA for Eca. The media upon which cells were grown also affected the A[sub=+.05] values but this effect was not proportional to the amount of growth observed. Based on these results it was concluded that until well to well variability is eliminated, and sensitivity increased, there will be little incentive to use the double sandwich ELISA technique with plant sap where a reduction in sensitivity is likely. At this point ELISA seems to have little potential in routine surveys for detecting latent blackleg infections in certified seed potatoes. / Land and Food Systems, Faculty of / Graduate

Tesis por compendio / Fire blight is considered the most serious disease affecting pome fruit and ornamental and wild rosaceae. The causal agent is the bacterium Erwinia amylovora, considered a quarantine organism in the EU. This species has been extensively studied, but at the genomic level there is still much to know, as there are currently only two genomes published and another thirteen were assembled in scaffolds. Its pangenoma is considered open, although with a core with a high sequence identity. There is very little intraspecific variability, which is manifested in a low genotypic diversity, being noticed that the plasmids are the major source of genetic variability. This could explain the differences in virulence in strains, as well as their better adaptation to the different environmental conditions. The plasmid pEA29 described in the majority of the strains of E. amylovora, and with a quantitative effect in virulence, was not found in some Spanish isolates of the bacterium. The study of these strains gave way to the discovery of another plasmid, pEI70, which is present in strains of several European countries. After pEA29, pEI70 is the one with the highest presence. The function, distribution and genetic content of this plasmid, as well as the effect of pEA29 and pEI70 on the expression of the chromosomal genes in strain bearing them, have been studied. The inoculation experiments on fruit with the strains to which the plasmid pEI70 or pEA29 had been introduced compared to that same strain without plasmids showed an increase in virulence, which was manifested in a reduction in the time of the emergence of symptoms and in which they appeared more aggressively. An experiment was carried out using a microarray, in order to study if the presence of each one of these plasmids could affect the expression on certain chromosomal genes that would explain that variation in virulence of the carrier strain, using a microarray. The results demonstrated the role of both plasmids to affect gene expression, between 120 and 180 chromosomal genes according to the plasmid carrying the strain, in each case enriching different functional categories, although 28 of them were coincident in the two cases. E. piriflorinigrans is a newly described pathogenic species that produces necrosis only in pear blossoms but does not appear to affect other organs. Both species share phenotypic and molecular characteristics, making their distinction difficult. Its detection and correct identification was a challenge because the symptoms it causes are practically indistinguishable from those caused by E. amylovora. In this work new plasmid pEPIR37 found in this new species was studied also. This is present in all analyzed strains. When this plasmid was introduced into strains of the species E. amylovora cured of plasmids, they showed an increase in virulence comparable to that observed with pEA29, suggesting that pEPIR37 produces a similar effect. Two specific and sensitive real-time and conventional PCR protocols have also been developed to identify, detect and differentiate E. piriflorinigrans from E. amylovora and other species of this genus using primers designed from specific sequences, annoted in this same work, from plasmid pEPIR37. This has allowed to identify this new species in other hosts as Pyracantha sp., besides pear tree and in other regions where previously it had not been detected. Likewise, these results have allowed to know biological and epidemiological aspects of E. piriflorinigrans that contribute to have new key scientific information to establish strategies for its control in pome fruit trees. The study of the plasmids and their functions in these two phylogenetically related species and their role in the adaptation to the environment in which these species live, as well as in the virulence of the strains that carry them, could give new clues about the origin of both pathogens, their evolution, their biological cycle and interaction with the host plant / El fuego bacteriano está considerada la enfermedad más grave que afecta a frutales de pepita y rosáceas ornamentales y silvestres. El agente causal es la bacteria Erwinia amylovora, perteneciente a la familia Erwiniaceae, organismo de cuarentena en la UE. Esta especie ha sido ampliamente estudiada, pero a nivel genómico todavía queda mucho por conocer, ya que en la actualidad existen únicamente dos genomas completamente secuenciados y anotados, y otros trece en scaffolds, de cepas de E. amylovora de diferentes orígenes geográficos y huéspedes. Su pangenoma se considera abierto, aunque con un core con una alta identidad de secuencia en estas cepas. Existe muy poca variabilidad intraespecífica, lo que se manifiesta en una escasa diversidad genotípica, advirtiéndose que los plásmidos son la mayor fuente de variabilidad genética que podría explicar las diferencias en virulencia en cepas portadoras de plásmidos, así como su mejor adaptación a diferentes condiciones ambientales. El plásmido pEA29 descrito en la mayoría de las cepas de E. amylovora, y con un efecto cuantitativo en virulencia. El estudio de estas cepas sin plásmido dio paso al descubrimiento de otro plásmido que se ha denominado pEI70, presente en cepas de varios países europeos. Se ha estudiado su función, distribución y contenido genético, así como el efecto del pEA29 y del pEI70 sobre la expresión de los genes cromosómicos de la cepa que los porta, tras la infección en fruto inmaduro. Los experimentos de inoculación con las cepas a las que se les había introducido el plásmido pEI70 o el pEA29, en comparación con esa misma cepa sin plásmidos, mostraron un aumento de la virulencia. Por todo ello, con el fin de estudiar si la presencia de cada uno de estos dos plásmidos podría producir efectos sobre determinados genes cromosómicos que explicarían esa variación en virulencia, se realizó un experimento de expresión génica diferencial usando un microarray. Los resultados demostraron el papel de ambos plásmidos al afectar a la expresión de entre 120 y 180 genes cromosómicos según el plásmido que porte la cepa, enriqueciéndose en cada caso categorías funcionales diferentes. Por otro lado, E. piriflorinigrans es una especie patógena descrita recientemente que produce necrosis sólo en las flores de peral, pero no parece afectar a otros órganos. Además, ambas especies comparten características fenotípicas y moleculares. Su detección y correcta identificación era un reto debido a que los síntomas que provoca en flores son prácticamente indistinguibles a los causados por E. amylovora. Se ha estudiado el contenido genético de un plásmido de 37 Kb, pEPIR37 presente en todas las cepas analizadas de la especie. Además, se ha observado que cuando este plásmido es introducido en cepas de la especie E. amylovora curadas de plásmidos, mostraron un nivel de virulencia mayor, comparable a la observada en las cepas portadoras del plásmido pEA29, lo que parece indicar que este plásmido produce un efecto similar. En este trabajo también se han desarrollado dos protocolos específicos y sensibles de PCR en tiempo real y convencional para identificar, detectar y diferenciar E. piriflorinigrans de E. amylovora y de otras especies de este género, usando secuencias específicas del plásmido pEPIR37. Ello ha permitido identificar esta nueva especie en otros huéspedes como en otras regiones en donde no se había detectado. Asimismo, estos resultados han permitido conocer aspectos biológicos y epidemiológicos de E. piriflorinigrans que aportan nueva información científica que resultaría para establecer estrategias para su control. El estudio de los plásmidos y sus funciones en estas dos especies tan relacionadas filogenéticamente y su papel en la adaptación al medio en el que ambas habitan, así como en la virulencia de las cepas que los portan, podría dar nuevas pistas sobre el origen de estos patógenos, su evolución / El foc bacterià està considerada la malaltia més greu que afecta arbres fruiters de pinyol i rosàcies ornamentals i silvestres. L'agent causal d'aquesta malaltia és el bacteri Erwinia amylovora, organisme de quarantena a la UE. Aquesta espècie ha estat àmpliament estudiada, però a nivell genòmic encara queda molt per conèixer, ja que en l'actualitat únicament existeixen dos genomes publicats, i altres tretze assemblades scaffolds. El seu pangenoma es considera obert, tot i que aquests soques posseeixen un core amb una alta identitat de seqüència. Hi ha molt poca variabilitat intraespecífica, el que es manifesta en una escassa diversitat genotípica, advertint-se que els plasmidis són la major font de variabilitat genètica que podria explicar les diferències en virulència a les soques, així com la seua millor adaptació a les condicions ambientals. El plasmidi pEA29 descrit en la majoria de les soques d'E. amylovora, i amb un efecte quantitatiu en virulència, no es va trobar en alguns aïllats espanyols del bacteri, donant pas al descobriment d'un altre plasmidi, pEI70. Per això, després del pEA29, el plasmidi pEI70 és el de major. S'ha estudiat la funció, distribució i contingut genètic d'aquest plasmidi, així com l'efecte del pEA29 i del pEI70 sobre l'expressió dels gens cromosòmics. Els experiments d'inoculació en fruit amb les soques amb els plasmidis van mostrar un augment de la virulència, que es manifestava en una reducció en el temps de l'aparició de símptomes i en què aquests es presentaven de forma més agressiva. Per tal d'estudiar si la presència de cada plasmidi podria produir efectes sobre determinats gens cromosòmics que explicarien aquesta variació en virulència de la soca portadora, es va realitzar un experiment d'expressió genètica diferencial mitjançant un microarray. Els resultats obtinguts van demostrar el paper dels dos plasmidis en afectar l'expressió d'entre 120 i 180 gens cromosòmics segons el plasmidi que porta la soca, enriquint-se en cada cas categories funcinals diferents, tot i que 28 d'ells van ser coincidents en els dos casos. E. piriflorinigrans és una espècie patògena descrita recentment que produeix necrosi només en les flors de perera. Les dues espècies comparteixen característiques fenotípiques i moleculars, fent difícil la seua distinció. La seua detecció i correcta identificació era un repte. En aquest treball també s'ha avaluat el contingut genètic d'un plasmidi de 37 Kb, anomenat pEPIR37, present en totes les soques analitzades de l'espècie E. piriflorinigrans, i a més s'ha observat que quan aquest plasmidi era introduït en soques de l'espècie E. amylovora curades de plasmidis, que per això tenen una virulència reduïda, van mostrar una virulència major, comparable amb l'observada en les soques portadores del plasmidi pEA29, el que indicaria que aquest plasmidi produeix un efecte similar.Per tot això en aquest treball també s'han desenvolupat dos protocols específics i sensibles de PCR en temps real i convencional per identificar, detectar i diferenciar E. piriflorinigrans d'E. amylovora i d'altres espècies d'aquest gènere, usant iniciadors dissenyats a partir de seqüències específiques, anotades en aquest mateix treball, del plasmidi pEPIR37. Això ha permès identificar aquesta nova espècie a altres hostes com Pyracantha sp., a més de perera i en altres regions on anteriorment no s'havia detectat. Així mateix, aquests resultats han permès conèixer aspectes biològics i epidemiològics d'E. piriflorinigrans que aporten nova informació científica clau per establir estratègies per al seu control en arbres fruiters de pinyol. L'estudi dels plasmidis i les seues funcions en aquestes dues espècies tan relacionades filogenèticament i el seu paper en l'adaptació al medi on habiten, així com en la virulència de les soques que els porten, podria donar noves pistes sobre l'origen dels dos patògens, la seua evolu / Barbé Martínez, S. (2017). Función y origen de los plásmidos en especies de Erwinia patógenas y epífitas de frutales de pepita [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86146 / Compendio

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Submitted by MARCOS LEANDRO TEIXEIRA DE OLIVEIRA (marcosteixeira@ufv.br) on 2018-09-18T12:47:00Z No. of bitstreams: 1 texto completo.pdf: 639206 bytes, checksum: dd32762cb50ada1c756583f194533ca7 (MD5) / Made available in DSpace on 2018-09-18T12:47:01Z (GMT). No. of bitstreams: 1 texto completo.pdf: 639206 bytes, checksum: dd32762cb50ada1c756583f194533ca7 (MD5) Previous issue date: 2017-07-21 / A seca-de-ponteiros, causada por Erwinia psidii é, atualmente, uma das doenças emergentes mais importantes na cultura do eucalipto no Brasil. Por se tratar de uma enfermidade recentemente descrita, pouco se sabe sobre a relação patógeno-hospeiro, cujo conhecimento pode auxiliar na determinação de medidas de controle. Assim, o presente estudo teve como objetivos: 1) Estudar a translocação e colonização de E. psidii em mudas de eucalipto; 2) Avaliar as alterações fisiológicas de plantas infectadas em relação a plantas sadias, principalmente quanto a trocas gasosas e danos ocorridos na maquinaria fotossintética e 3) Avaliar diferentes espécies de Eucalyptus e Corymbia quanto à resistência à seca-de ponteiros e ampliar o conhecimento sobre a gama de hospedeiros da bactéria em espécies da família Myrtaceae. No primeiro estudo, por meio de microscopia eletrônica de varredura, determinou-se que a colonização é principalmente acropetal e ocorre pelos vasos do xilema. Além dos vasos xilemáticos, a bactéria coloniza os espaços intercelulares e os tecidos parenquimáticas. Dentro destes tecidos, as células bacterianas formam agregados, que podem conter material fibrilar envolvendo-as, o que sugere a formação de biofilme, o qual pode desempenhar importante papel na agressidade da bactéria. No segundo estudo, não se detectaram alterações de trocas gasosas nem de fluorescência da clorofila a de plantas do clone resistente inoculadas ou não inoculadas. Entretanto, nas plantas do clone suscetível, houve redução significativa nos valores de taxa de assimilação líquida de CO 2 , condutância estomática ao vapor de água, concentração interna de CO 2 , taxa de transpiração, máxima eficiência fotoquímica, rendimento da fotoquímica, rendimento para dissipação e aumento nos valores de rendimento por outras perdas não-fotoquímicas em relação às plantas não-inoculadas (testemunhas) do mesmo clone. A infecção de E. psidii alterou a maquinaria fotossintética das plantas do clone suscetível principalmente quanto aos mecanismos de fotodissipação e fotoproteção. No terceiro estudo, por meio de inoculações conduzidas em casa de vegetação, determinou-se que todas as outras oito espécies da família Myrtaceae avaliadas foram suscetíveis à seca de ponteiros, constituindo potenciais novos hospedeiros do patógeno. Encontrou-se, contudo, ampla variação na intensidade da doença entre as 28 espécies de Eucalyptus e quatro de Corymbia testadas. A variabilidade intra e interespecífica quanto à resistência permite a seleção de materiais superiores para plantio. Os resultados deste trabalho fornecem informações importantes sobre a interação E. psidii - eucalipto e para o estabelecimento de estratégias de controle da doença por meio do plantio de genótipos resistentes. / Dieback caused by Erwinia psidii is one of the most important emerging diseases eucalypt in Brazil. Because it is a disease recently described in eucalypt, little is known about host-pathogen relations, which knowledge may help in establishing control measures. Thus, the present study aimed: 1) to study translocation and colonization of E. psidii in eucalypt cuttings; 2) to evaluate the physiological changes, estimated by gas exchanges and damages in the photosynthetic machinery and 3) to evaluate resistance of Eucalyptus spp., Corymbia spp. and several other species of Myrtaceae.to E. psidii. In the first study, we found that colonization occurs mainly acropetally by xylem vessels. In addition to the xylem vessel, the bacterium colonizes the intercellular spaces and the parenchyma cells. Intracellularly, bacterial cells form clusters, which may contain fibrillar material, suggesting biofilm formation, which may play an important role in agressiveness of the te bacterium. In the second study, no differences in gas exchange or chlorophyll fluorescence parameters were detected in either inoculated or non-inoculated plants of a resistant clone, but net CO 2 assimilation rate, stomatal conductance to water vapor, internal CO 2 concentration, transpiration rate, maximum quantum yield, effective PSII quantum yield, quantum yield of regulated energy dissipation, quantum yield of non-regulated energy dissipation were altered in infected plants in relation to non-inoculated (control). Changes occurred in photosynthetic machinery of the susceptible clone mainly for photodisipation and photoprotection mechanisms. In the third study, through inoculations conducted in greenhouse, it was determined that all the other eight species of the Myrtaceae family evaluated were susceptible to dieback, constituting potential new hosts of the pathogen. However, there was a wide variation in disease intensity of 28 species of Eucalyptus spp. and four species of Corymbia spp. tested. The intra and interspecific variability of the resistance allows the selection of superior materials for planting. The results of this work provide important information on the host-pathogen interactions between E. psidii - eucalyptus and the establishment of strategies of disease control by selecting and planting resistant genotypes.

Orientador: Ranulfo Monte Alegre / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-07-20T18:52:17Z (GMT). No. of bitstreams: 1 Flores_SimoneHickmann_M.pdf: 3479929 bytes, checksum: 5c22c3b142d6f7436af633378a5e4c36 (MD5) Previous issue date: 1995 / Resumo: Soro de queijo integral e/ou desproteinado por acidificação e aquecimento podem ser utilizados como meio de cultura para produção de lactase de Erwinia aroideae NRRL B-132. A maior atividade de lactase obtida em fermentação de soro de queijo desproteinado (434,10 UI/m1) foi com 55 g/l de lactose, em doze horas de fermentação em erlenrneyer com produção de 1,9 g/l de massa celular seca. A suplememtação do meio de cultura com 5g/1 de asparagina aumentou em 15% a atividade da enzima intracelular e 202% a atividade da enzima extracelular. A temperatura ótima de incubação da enzima para hidrólise de ONPG foi 45°C e pH na faixa de 7,5 a 8,0. Em fermentador de 6 litros variou-se a temperatura de fermentação (25, 27, 30, 32 e 35°C) mantendo-se a taxa de aeração em 1 vvm e rotação de 350 rpm. Obteve-se maior atividade de lactase quando foi utilizado soro de queijo integral. A 30°C a produção em lactase extracelular foi maior e a 32°C houve maior produção de lactase intracelular. Utilizou-se o modelo matemático de Michaelis-Mentem para carac~erizar cineticamente a enzima, obtendo-se o valor para K.m de 3,46, 3,62, 3,85 e 0,60: mM para as temperaturas de 20, 23, 25 e 27°C ,respectivamente. A energia de ativação para K.m, determinada pelo modelo de Arrhenius foi 3.84 Kcal/mol. A inativação da enzima nas temperaturas de 45, 47, 49 e 50°C seguiu cinética de primeira ordem com constante de inativação Kd de 23,20, 47,60, 60,20 e 90,90 mM, respectivamente, e energia de ativação para a desnaturação Ed 51,50 KcaVmol. A enzima apresentou baixa estabilidade quando quando pré-incubada em pH diferente do ótimo por 20 minutos. / Abstract: Production of intra and extracellular /3-galactosidase by Erwinia aroidea grown in cheese whey was studied. Preliminary experiments with edenrneyers and desproteinized cheese whey showed the optimallactose concentration of 5.5% when the lactase activity achieved 434.10 VI/ml and cellular dried mass' 1.9048 g/l for 12 hours culture. Optimals temperature and pH for ONPG hidrolysis was 45°C and 7.5, respectively. Medium culture suplementation with asparagine (5g/l) caused an increase of 15% in intracellular enzyme activity and of 202% in extracellular enzyme activity. Fermentation experi1:nents were carried out in 6 liters fermenter; it was used integral and deproteinized cheese whey under temperatures of 25, 27, 30, 32 and 35° C, 350 rpm and 1 vvm for 12 hours culture. When integral cheese whey was used the largest activity was achieved compared with the deproteinized cheese whey. The production of extracellular enzyme was greater at 30°C and the largest production of intracellular enzyme was obtained at 32°C. Enzyme inibition by temperature ocçured above 32°C. Glucose in culture medium caused enzyme carbon catabolite repression. Kinectis parameters was obtained through Michaelis-Mentem model ; Km for ONPG was 3.46 mM, 3.62 mM, 3.85 mM and 0.5960 mM at 20, 23, 25 and 27°C, respectively. The activation energy for ONPG hidrolysis was 3.84 Kcallmol °K. In stability study, it was obtained Kd values of 23.20 mM, 47.60 mM, 60.20 mM and 90.90 mM at 45, 47, 49 and 50°C, respectively. The activation energy for denaturation was 51.50 Kcal/mol °K. Enzyme low pH stability was observed and this fact means that it must be used around the optimum value (7.5 - 8.0). / Mestrado / Mestre em Engenharia de Alimentos

Magistrantūros studijų baigiamajame darbe pateikiami internetinės prognozavimo „iMETOS®sm“ sistema atlikti bakterinės degligės rizikos faktorių analizė bei prognozavimo galimybes Lietuvos versliniuose soduose Darbo objektas –. obelys (Malus); ligos sukėlėja - bakterinė degligė (Erwinia amylovora Burr.). Darbo metodai: tiriamas meteorologinės stotelės Pessl Instruments „iMETOS®sm“ Erwinia amylovora Burr. infekcijos rizikos prognozavimo modelio pritaikymas Lietuvos versliniuose soduose. Darbo rezultatai. 2011 m. Lietuvos agrarinių ir miškų mokslų centro filialo Sodininkystės ir daržininkystės institute atlikti tyrimai prognuozuojant bakterinės degligės (Erwinia amylovora Burr.) pasireiškimo galimybes Lietuvos versliniuose soduose taikant internetinę „iMETOS®sm‘‘prognozavimo sistemą. Bakterinės degligės prognozavimo modelis numato skirtingus ligos pasireiškimo fonus (PETΣ): 1) paskutinius du sezonus degligės nebuvo; 2) paskutinius du sezonus degligė pasireiškė atskirose vietose; 3) praeitą sezoną degligė pasireiškė atskirose vietose; 4) bakterinė degligė aptikta šalia sodo; 5) netoliese dabar aktyvios degligės žaizdos. Visuose stebėtuose ūkiuose per 2011 m. vegetacijos periodą bakterinės degligės prognozavimo modelis apskaičiavo iš viso 310 dienų, kai bakterinės degligės infekcijos rizikos indeksas DIV rodė didžiausią E. amylovora pasireiškimo galimybę pagal PETΣ. Stebėtuose obelų soduose, kai paskutinius du sezonus degligės sode nebuvo, nustatyta, kad didžiausia patogeno... [toliau žr. visą tekstą] / Master’s thesis submitted to the online prediction "sand'' iMETOS ® forecasting system to perform fire blight risk factor analysis and the predictive ability of Lithuanian business orchards. Object of the work- apple (Malus) to cause disease - a fire blight (Erwinia amylovora Burr.). Method of the work: working methods studied meteorological station Pessl Instruments iMETOS ® sm 'Erwinia amylovora Burr. infection risk prediction model for Lithuanian business orchards. The results of work. In 2011. Lithuanian Institute of Agrarian and Forest Sciences Centre branch of the Institute of Horticulture forecasting studies of fire blight (Erwinia amylovora Burr.) The possibility of a Lithuanian business orchards using an online "sand'' iMETOS ® forecasting system. Fire blight forecasting model for the different disease backgrounds (PETΣ): 1) the last two seasons were not fire blight, 2) the last two seasons fire blight occurred in different places, and 3) last season fire blight occurred in different places, 4) fire blight found near the orchards, 5) nearby is now active fire blight wounds. All the observed farms in 2011. fire blight vegetation period forecasting model documented a total of 310 days after infection, fire blight DIV risk index showed the highest E amylovora by PETΣ to occur. Apple orchards in all observed the last two seasons did not fire blight the garden, it was found that the greatest manifestation of the pathogen by orchards PETΣ option was: „Luksnėnų sodai” UAB... [to full text]