The physiological literature on Nitrobacter is reviewed and a list of the unsolved problems presented. Modifications to the action spectrum apparatus built by Brooks (1967) are described. The apparatus was then used with Nitrobacter agilis, ATCC no. 14123, to obtain an action spectrum of the relief of carbon monoxide inhibition by light. The results of this study indicate that cytochrome a₁ is active as a terminal oxidase. The possibility of other cytochromes, principally cytochrome ₀, acting as oxidases has not been proven or ruled out. The results of a study on the rate of oxygen uptake versus oxygen concentration are also reported; the Km(0₂) values range from 0.021 to 0.055 mM oxygen. The action spectrum reported here is the. first one to be determined on a chemolithotropic bacterium. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

<p>Nitrification is a natural occurring, oxidative process which is essential for plants´ ability to take up nitrogen in the form of nitrate. The oxidation is divided into two steps. First ammonia is oxidized to nitrite by ammonia-oxidizing bacteria (AOB) or archaea (AOA) and then the nitrite is further oxidized to nitrate by nitrite-oxidizing bacteria (NOB). The enzyme used by NOB for the oxidation is nitrite oxidoreductase (nxr). One of few bacteria that catalyze this reaction is Nitrobacter sp.</p><p>The purpose of this study has been to optimize the detection of Nitrobacter in samples of activated sludge from municipal wastewater treatment plants (WWTPs) in Eskilstuna and Västerås (Sweden). This was done by PCR, cloning and sequencing. Primers used were nor F/nor R that are specific for the functional gene encoding nxr. This optimization has been compared to a different PCR-system where nor F/nor R were exchanged for another primerpair consisting of a 16S rDNA-primer (NIT3), which was specific for Nitrobacter and a universal 16S-primer (U2, Rit388). In addition to this, a semi quantitative analyze has also been conducted.</p><p>The result of the study was two PCR-programmes, one optimized for each set of sludge samples. The quantitative analysis showed that the concentration Nitrobacter in the sludge samples was approximately the same as a pure culture, which was used as a positive control and contained ~10⁴ CFU/ml.</p><p>Cloning and sequencing revealed the presence of 3 different Nitrobacter. Surprisingly half of the clones from one of the Västerås samples, taken in December, were most likely Methylibium petroleiphilum. The matter of fact that we were able to detect this bacterium with primers specifically designed for Nitrobacter made this discovery even more interesting. With NIT3/U2 Methylocella sp. was also detected in samples from Västerås, which confirmed the presence of methylotrophic bacteria in the Västerås samples.</p><p> </p> / Activated sludge process optimization

Nitrification is a natural occurring, oxidative process which is essential for plants´ ability to take up nitrogen in the form of nitrate. The oxidation is divided into two steps. First ammonia is oxidized to nitrite by ammonia-oxidizing bacteria (AOB) or archaea (AOA) and then the nitrite is further oxidized to nitrate by nitrite-oxidizing bacteria (NOB). The enzyme used by NOB for the oxidation is nitrite oxidoreductase (nxr). One of few bacteria that catalyze this reaction is Nitrobacter sp. The purpose of this study has been to optimize the detection of Nitrobacter in samples of activated sludge from municipal wastewater treatment plants (WWTPs) in Eskilstuna and Västerås (Sweden). This was done by PCR, cloning and sequencing. Primers used were nor F/nor R that are specific for the functional gene encoding nxr. This optimization has been compared to a different PCR-system where nor F/nor R were exchanged for another primerpair consisting of a 16S rDNA-primer (NIT3), which was specific for Nitrobacter and a universal 16S-primer (U2, Rit388). In addition to this, a semi quantitative analyze has also been conducted. The result of the study was two PCR-programmes, one optimized for each set of sludge samples. The quantitative analysis showed that the concentration Nitrobacter in the sludge samples was approximately the same as a pure culture, which was used as a positive control and contained ~104 CFU/ml. Cloning and sequencing revealed the presence of 3 different Nitrobacter. Surprisingly half of the clones from one of the Västerås samples, taken in December, were most likely Methylibium petroleiphilum. The matter of fact that we were able to detect this bacterium with primers specifically designed for Nitrobacter made this discovery even more interesting. With NIT3/U2 Methylocella sp. was also detected in samples from Västerås, which confirmed the presence of methylotrophic bacteria in the Västerås samples. / Activated sludge process optimization

Les procédés actuellement utilisés à bord de la Station Spatiale Internationale permettent un traitement physico-chimique des déchets avec un recyclage partiel des éléments en minimisant le réapprovisionnement en eau et oxygène. Voyager plus loin et sur de plus longues durées n’est possible que si un système de support de vie, permettant d’assurer une autonomie plus importante, est mis en place. Le projet MELiSSA est un système de support de vie biorégénératif ayant pour objectifs de recycler les déchets produits par l’homme, de régénérer l’oxygène et l’eau et d’assurer une production de nourriture. L’utilisation de microorganismes pour assurer ces différentes fonctions, n’est réalisable qu’en ayant la meilleure connaissance possible et surtout la maîtrise des processus et des souches impliqués. L’objectif de cette thèse est de développer un modèle prédictif pour le compartiment nitrificateur de la boucle MELiSSA. Dans un premier temps, les souches Nitrosomonas europaea ATCC® 19718 et Nitrobacter winogradskyi ATCC® 25391 ont été étudiées et ont permis de définir un modèle cinétique de ces deux bactéries en culture immergée. Dans un second temps, ce modèle a été combiné à un modèle N-bacs en série pour composer un modèle de nitrification dans une colonne à lit fixe à biomasse fixée : le modèle NitriSim. Ce modèle a été testé sur une expérience de long-terme menée dans une colonne à lit fixe dont le support est composé de billes Biostyr®. Le dernier chapitre de ce manuscrit décrit l’utilisation d’une souche dégradant l’urée, Cupriavidus pinatubonensis, dans le réacteur à lit fixe. Les différents résultats ont permis de définir un modèle de nitrification dans un réacteur à lit fixe et de présenter des perspectives possibles pour le traitement de l’urine au niveau du compartiment nitrifiant de MELiSSA. / Physico-chemical processes are used on the International Space Station for partial recycling of wastes in order to minimize the resupplies of oxygen and water. Further and longer explorations can only be possible if a life support system is applied to enhance autonomy to the station. MELiSSA is a biological life support system project aiming for waste recycling, water and air regeneration and production of simple food. The only way to assure these functions is the use of microorganisms which is requiring a high knowledge and a perfect control of processes implicated. The thesis objectives consist in developing a predictive model for the MELiSSA nitrifying compartment. First, a kinetic study of Nitrosomonas europaea ATCC® 19718 and Nitrobacter winogradskyi ATCC® 25391 in submerged bioreactors allowed defining a kinetic model of nitrification. Secondly, this model was combined to an N-tanks in series one to compose a nitrification model in fixed-bed biorectors : NitriSim. It was applied on a long-term experiment in a fixed-bed bioreactors where the bed was composed of Biostyr® beads. The last part of this work was about the use of a urea-degradating bacteria, Cupriavidus pinatubonensis, in the fixed-bed bioreactor. All of these results leaded to the development of a nitrification in fixed-bed reactors model and opened up interesting prospects for the urine degradation in the nitrifying compartment of MELiSSA.

I Sverige finns det ungefär 25 000 riskklassade förorenade områden samt ännu fler områden som potentiellt är förorenade. Naturvårdsverket har tagit fram generella riktvärden för olika förorenade ämnen. Halter över riktvärdena antyder att risken för negativa effekter på människan eller miljön bedöms vara stor och att efterbehandling av området är aktuellt. Ett vanligt, men kostsamt efterbehandlingsalternativ är urschaktning och bortforsling av jord innehållandes halter av ämnen över riktvärdena. Ett intresse finns för att utveckla lätt tillämpbara metoder för platsspecifik riskbedömning av mark i syfte att skydda markmiljön och dess funktioner. Mikroorganismer som ingår i kvävets kretslopp utför nyckelfunktioner i jorden. Flera studier indikerar att dessa mikroorganismers abundans och aktivitet påverkas av flera olika markföroreningar. Inom forskningsprojektet APPLICERA har ett lysimeterexperiment genomförts där två jordar, med olika egenskaper med avseende på bland annat kornstorleksfördelning och pH (svagt basisk sandy loam respektive sur sand), förorenats med koppar respektive PAH:er i varierande halter. Halterna motsvarar riktvärden för känslig markanvändning (KM), mindre känslig markanvändning (MKM) och 3xMKM. Provtagning av jorden har skett vid tre tillfällen under en period av 16 månader. I detta examensarbete har nitrifierande mikroorganismers potential för att användas som indikatorer för förändrad markfunktion i förorenad jord undersökts. Detta har gjorts genom att kvantifiera ammoniakoxiderande arkéer (AOA), ammoniakoxiderande bakterier (AOB) samt de nitritoxiderande bakteriesläktena Nitrospira och Nitrobacter i jord som provtagits vid de olika tidpunkterna i lysimeterexperimentet. Mätning av potentiell ammoniakoxidation (PAO) har skett för jord från det sista provtagningstillfället. Resultaten visade att abundansen av mikroorganismerna generellt var större i den svagt basiska jorden klassificerad som sandy loam än i den sura jorden klassificerad som sand. Med tiden minskade AOA:s abundans för den högsta koncentrationen av koppar och PAH, särskilt utpräglad var minskningen i den sura jorden. Även Nitrospira minskade i abundans i PAH-förorenad jord för båda jordtyperna, dock kunde en minskning i abundans i kopparförorenad jord statistisk endast säkerställas för den sura jorden. AOB:s och Nitrobacters abundans visade inte på någon tydlig uppåt- eller nedåtgående trend varken över tid eller för ökande föroreningshalt. Skillnaden i kvantitet av mikroorganismer mellan jordtyperna antyder att jordens kemiska och fysiska egenskaper påverkade mikroorganismernas abundans såväl som föroreningarnas biotillgänglighet. PAO minskade med ökande kopparhalt för båda jordtyper, däremot sågs en minskning i PAO med ökande PAH-halt endast i den sura jorden. Resultaten antyder att abundansen av AOA och Nitrospiras verkar ha störst potential att utgöra generella indikatorer över ändrad markfunktion, dock lämpligen med komplettering av förbättrade mätningar av PAO för att få mer information om kvävets kretslopp i förorenad jord. / In Sweden there are around 25,000 contaminated areas classified as a risk for human health or the environment, and even more potentially contaminated areas. The Swedish Environmental Protection Agency has developed generic guideline values for hazardous substances.  Contamination levels exceeding the guideline values indicate a large risk for human health or the environment and that there is a need to remediate the site. A frequently used and expensive aftertreatment is excavation and removal of contaminated soil. Therefore, there is an interest to develop easy applicable methods for site-specific risk assessment with the purpose to protect the soil environment and its functions. Microorganisms involved in the nitrogen cycle perform key functions in soil. Several studies indicate that the abundance and activity of N-cycling microorganisms are sensitive to various soil pollution. Within the research project APPLICERA, a lysimeter experiment was conducted with two different soil types (acidic sandy soil and slightly alkaline sandy loam) and different contamination levels of copper and PAH. The contamination levels corresponded to generic guideline values for sensitive land-use (KM), less sensitive land-use (MKM) and 3xMKM. Soil samples were taken at three times during a period of 16 months. The aim of this master thesis was to investigate nitrifying microorganism potential as indicators for altered soil functioning in contaminated soil. Ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB) and the nitrite-oxidizing bacteria genera Nitrospira and Nitrobacter has been quantified in soil samples with the different treatments. Measurements of the potential ammonia oxidation (PAO) have been performed in soil from the last sample taking.  The abundance of the nitrifying microorganisms was in general higher in the slightly alkaline sandy loam soil. Over time there was a decrease in AOA abundance for the highest concentration of copper and PAH, most pronounced in the acidic sandy soil. Also, a decrease in the abundance of Nitrospira in soil contaminated with PAHs could be seen for both soil types. In copper contaminated soil a distinct decrease in the abundance of Nitrospira could only be seen in the acidic sandy soil. The abundance of AOB and Nitrobacter did not show any obvious pattern for different contamination levels or over time. The difference in abundance of nitrifying microorganisms between the soil types suggests that the soil’s chemical and physical characteristics as well as the bioavailability of the contaminant affected their abundance. A significant decrease in PAO could be seen for the highest contamination level of copper for both soil types, but for the PAH contaminated soil PAO decreased only in the acidic sandy soil. These results suggest that the abundance of AOA and Nitrospira seems to have greatest potential as general indicators for altered soil functioning. However, improved activity measurements are needed to gain greater insight into the soil N-cycle functioning in contaminated soils.

Made available in DSpace on 2014-12-17T15:03:23Z (GMT). No. of bitstreams: 1 TatianaCD_DISSERT.PDF: 3494650 bytes, checksum: b64da14488429ca5572f84e37365b101 (MD5) Previous issue date: 2009-11-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study investigates a new treatment system of wastewater by anaerobic and aerobic biological filters for nitrogen modification. The main objective of this study was evaluate, on a pilot scale, quantitatively and qualitatively the bacterian nitrifying community in a experimental sewage treatment system made by aerobics biological filters in series, in search of figure out the dynamic of nitrogen modification process. It was collected and laboratorial analysed microbiologically, regarding NMP of Nitrosomonas e Nitrobacter, and physical-chemically considering nitrogen sequence. We conclude that: the association in aerobic biological filters under nutrition controlled conditions and oxygen level allows the appearance of bacterian community responsible for the nitrogen modification; the method used, despite its limitations, provided the selection of autotrophic nitrifying microorganisms, allowing the identification of Nitrosomonas and Nitrobacter; the flow direction tested in the experimental unit did not affect the nitrifying bacterial community, certainly because they were kept drowned and did not occur flow speed that could breake the formed biomass; the nitrification process happened in aerated biological filters in all phases of the research, comproved by microbiological tests; in the third phase of the research the increase of the oxygen rate was significant for the nitrificant bacterian community in the aerate biological filters, allowing its growth, occurring relation between the efficiency of nitrification system and the quantity of organisms responsible for this process; the conduit used in aerated biological filters showed satisfactory performance support material to the nitrifying bacteria development / Neste estudo foi pesquisado um novo sistema de tratamento de efluente com filtros biol?gicos anaer?bios e aer?bios, visando a transforma??o das formas de nitrog?nio. O principal objetivo deste trabalho foi avaliar, em escala piloto, quantitativamente e qualitativamente a comunidade bacteriana nitrificante em um sistema de tratamento de esgoto experimental composto por filtros biol?gicos submersos aerados em s?rie, para compreender a din?mica no processo de transforma??o de nitrog?nio. Para tal, foram feitas coletas e an?lises laboratoriais tanto microbiol?gicas, no que diz respeito ? NMP de Nitrosomonas e Nitrobacter, quanto f?sico-qu?micas, com rela??o ? seq??ncia nitrogenada. Diante dos resultados obtidos p?de-se concluir que: a associa??o em s?rie de filtros biol?gicos aer?bio sob condi??es controladas de nutri??o e n?vel de oxig?nio permitiu a forma??o da comunidade bacteriana respons?vel pela transforma??o de nitrog?nio; o m?todo utilizado, apesar de suas limita??es, propiciou a sele??o de microorganismos autotr?ficos nitrificantes, permitindo a identifica??o de Nitrosomonas e Nitrobacter; os sentidos de fluxo testados na unidade experimental n?o influenciaram a comunidade bacteriana nitrificante, certamente porque foram mantidos afogados e n?o ocorreu velocidade de fluxo capaz de cisalhar a biomassa formada; o processo de nitrifica??o ocorreu nos filtros biol?gicos aerados em todas as fases da pesquisa, tendo sido isto comprovado pelos exames microbiol?gicos; na terceira fase da pesquisa o aumento da taxa de oxigena??o foi significativo para a comunidade bacteriana nitrificante nos filtros biol?gicos aerados, favorecendo seu crescimento, havendo desta forma rela??o entre a efici?ncia do sistema na nitrifica??o e a quantidade de organismos respons?veis por esse processo; os an?is de eletroduto utilizado nos filtros biol?gicos aerados mostraram desempenho satisfat?rio como material suporte para o desenvolvimento bacteriano nitrificante

Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-08-07T20:04:03Z No. of bitstreams: 1 TUILLY DE FÁTIMA MACEDO FURTADO GUERRA – DISSERTAÇÃO (PPGECA) 2016.pdf: 2570702 bytes, checksum: dc3123f0ac79b6573767e39e1c19c4c4 (MD5) / Made available in DSpace on 2018-08-07T20:04:03Z (GMT). No. of bitstreams: 1 TUILLY DE FÁTIMA MACEDO FURTADO GUERRA – DISSERTAÇÃO (PPGECA) 2016.pdf: 2570702 bytes, checksum: dc3123f0ac79b6573767e39e1c19c4c4 (MD5) Previous issue date: 2017-03-17 / Capes / O processo Anammox essencialmente é a desnitrificação autotrófica na qual nitrogênio amoniacal é oxidado por nitrito para nitrogênio molecular. O nitrito pode ser produzido em águas residuárias pela oxidação da amônia pelas Nitrosomonas. Todavia, tem-se que evitar que as bactérias do gênero Nitrobacter se desenvolvam para evitar a oxidação do nitrito para nitrato. O processo Anammox se aplica particularmente em águas ricas em amônia e pobres em material orgânico, como por exemplo, efluentes de digestores anaeróbios. Na prática tem sido aplicado com sucesso para efluentes de digestores de lodo aquecidos a 37 °C, mas a aplicação à temperatura ambiente na Europa (5 a 15 °C) não tem sido eficiente, pela dificuldade de eliminação da etapa de nitratação. Na presente pesquisa, procurou-se estabelecer se a nitrificação parcial é factível para a faixa de temperatura de esgotos no Brasil, para uma possível aplicação do processo Anammox visando à remoção de nitrogênio dos efluentes de reatores UASB. Para tanto, foram determinadas as constantes cinéticas da nitritação e nitratação em um sistema de lodo ativado entre a faixa de temperaturas de 12,7°C a 31 °C e as constantes de meia saturação do oxigênio dissolvido. A respirometria foi a ferramenta utilizada para determinar as taxas de nitritação e de nitratação e estimar as outras constantes cinéticas relevantes, sendo mostrado pelos resultados que esta é uma ferramenta útil na determinação das constantes cinéticas. Os valores encontrados das constantes cinéticas de crescimento das nitritadoras e nitratadoras em função da temperatura mostraram uma tendência de prevalecimento da nitritação sobre a nitratação em toda a faixa avaliada. Através da determinação da idade lodo mínima para a nitritação e nitratação pode-se estimar que operando um sistema de lodo ativado a temperatura ambiente adotando uma idade de lodo de 4 dias é possível promover a nitrificação parcial. / The Anammox process is essentially autotrophic denitrification in which ammoniacal nitrogen is oxidized by nitrite to molecular nitrogen. Nitrite can be produced in wastewater by the oxidation of ammonia by Nitrosomonas. However, it has to be avoided that bacteria of the genus Nitrobacter develop to avoid the oxidation of nitrite to nitrate. The Anammox process is applied particularly in ammonium rich waters and poor in organic material, such as effluent from anaerobic digesters. In practice it has been successfully applied to effluent from sludge digesters heated to 37 ° C, but application at room temperature in Europe (5 to 15 ° C) has not been efficient due to the difficulty of eliminating the nitration step. In the present research, it was tried to establish if the partial nitrification is feasible for the range of sewage temperature in Brazil, for a possible application of the Anammox process aiming at the removal of nitrogen from UASB reactor effluents. For this, the kinetic constants of nitriding and nitration were determined in an activated sludge system between the temperature range of 12.7 ° C to 31 ° C and the half-saturation constants of the dissolved oxygen. The respirometry was the tool used to determine nitration and nitration rates and to estimate the other relevant kinetic constants, and it is shown by the results that this is a useful tool in the determination of kinetic constants. The values of the kinetic constants of the nitriding and nitrating agents as a function of temperature showed a tendency of nitriding over nitration over the entire range. By determining the age minimum sludge for nitriding and nitration it can be estimated that operating a sludge activated system at room temperature adopting a sludge age of 4 days can promote partial nitrification.