As enfermidades virais sÃo as que causam maiores prejuÃzos registrados na carcinicultura. O surgimento do IMNV no Nordeste do Brasil em 2002 colocou os produtores de camarÃo frente a uma enfermidade desconhecida que causou perdas significativas para o setor, tornando imperativo buscar um maior conhecimento sobre a doenÃa e de como podem se comportar outras espÃcies de camarÃo ao vÃrus do IMN. O objetivo deste trabalho foi avaliar a susceptibilidade do camarÃo rosa Farfantepenaeus subtilis, nativo da costa brasileira, atravÃs de teste de desafio frente ao IMNV. Para realizaÃÃo do bioensaio foram utilizados 200 camarÃes jovens saudÃveis mantidos em tanques individuais de 4L durante 30 dias. No experimento os camarÃes foram separados em dois grupos: controle e desafiado; o grupo desafiado foi alimentado com mÃsculo de L. vannamei contaminado com IMNV e o controle alimentado com mÃsculo de L. vannamei livre do vÃrus em estudo, durante 3 dias via âper osâ. ApÃs o desafio foram realizadas coletas aleatÃrias de 40 animais, 20 camarÃes controle e 20 camarÃes desafiados, a cada cinco dias (5Â; 10Â; 15Â; 20 e 30Â) onde durante cada coleta, foram extraÃdas hemolinfa para contagem total de hemÃcitos (CTH), brÃnquias para anÃlise de RT/PCR e em seguida cada camarÃo foi fixado com soluÃÃo de Davidson para anÃlise histolÃgica. As anÃlises moleculares, utilizando a metodologia do Kit IQ2000, mostraram que dos 100 animais desafiados apenas dez (10 %) se mostraram positivos à infecÃÃo. Nas anÃlises histolÃgicas foi observado uma baixa infiltraÃÃo hemocÃtica nos mÃsculos; uma leve coagulaÃÃo e presenÃa de hemolinfa entre as fibras musculares caracterizando uma infecÃÃo leve. De acordo com o teste t de Student para dados independentes, houve diferenÃa estatisticamente significativa (p≥ 0,05) entre a contagem total de hemÃcitos do grupo desafiado e grupo controle na amostragem do 30 dia. O estudo demonstrou que a espÃcie nativa Farfantepenaeus subtilis à susceptÃvel ao vÃrus IMN. / Viral diseases are causing great damage in shrimp farming. With the IMN virus emergence in Northeastern Brazil in 2002, the shrimp producers faced an unknown disease that caused significant losses for the industry. Thus, a better knowledge about this disease and the investigation of how other species of shrimp are affected by the IMN virus will be an important contribution for the aquaculture industry. The objective of this study is to evaluate the susceptibility of Farfantepenaeus subtilis from the Brazilian coast, to the IMN virus. To conduct the bioassay it was used 200 healthy young shrimps kept in individual tanks of 4L for 30 days. The experimental design was composed by two separated groups: a control group and a challenged one which was exposed to the IMN virus. The challenged group was fed on L. vannamei muscle contaminated with IMNV and the control group was fed on muscle of L. vannamei free of the virus, for 3 days per os. After the challenge procedures, random samples of 40 animals, 20 control and 20 challenged were taken, every five days (5Â, 10Â, 15Â, 20 and 30Â). On each sampling hemolymph was drawn for the total count of hemocytes (THC), gills were taken for analysis by RT / PCR and then each animal was fixed with Davidson solution for histological analysis. The molecular analysis, using the methodology of Kit IQ2000, showed that among 100 animals challenged only ten (10%) were positive for infection. In histological analysis a low hemocyte infiltration was observed in muscles and a slight presence of hemolymph coagulation was detected between muscle fibers characterizing a mild infection. According to the Student t test for independent data, there was a statistically significant difference (p ≥ 0.05) between the THC of challenged group and the control group sample of 30 days. The study showed wild specimens of F. subtilis to be susceptible to infection with IMNV.

Esporos de Bacillus subtilis apresentam propriedades adjuvantes, sendo capazes de aumentar a resposta humoral após a sua coadministração com antígenos misturados ou adsorvidos à sua superfície. Mas, para isso, é necessária a produção de esporos altamente purificados e com rendimentos elevados. Neste trabalho, realizamos com sucesso uma análise quantitativa das condições de esporulação e dos métodos de purificação, o que melhorou a reprodutibilidade do processo e a obtenção de amostras com elevado grau de pureza e rendimento. Avaliamos também as propriedades imunomodulatórias destes esporos, utilizando como antígeno modelo a proteína recombinante Gag-p24 do HIV-1. A coadministração, mas não a adsorção à superfície do esporo, aumentou a imunogenicidade do antígeno sem induzir efeitos deletérios após a administração parenteral em camundongos BALB/c e C57BL/6. Além de promoveram a ativação das APCs, os esporos interagem com receptores relacionados à imunidade inata, devido à ausência do efeito adjuvante em camundongos nocautes para TLR2. Esses resultados abrem perspectivas interessantes para a utilização de esporos como adjuvantes vacinais. / Bacillus subtilis spores have been shown to behave as vaccine adjuvants, promoting the increase of antibody responses after co-administration with antigens either admixed or adsorbed on the spore surface. Nonetheless, such specialized application requires highly purified spore preparations at high yields. In this work, we successfully performed a systematic quantitative analysis of sporulation conditions and spore purification methods, which improved the reproducibility of the process and the obtainment of samples with high purity and yield. Afterwards, we further evaluated the immune modulatory properties of these spores using a recombinant HIV-1 Gag-p24 protein as a model antigen. The co-administration, but not adsorption to the spore surface, enhanced the immunogenicity of that target antigen, without inducing deleterious effects, after subcutaneous administration to BALB/c and C57BL/6 mice. Besides promoting activation of antigen presenting cells, spores interact with receptors related to innate immunity, due to the absence of the adjuvant effect on TLR2 knockout mice. These results open interesting perspectives for the use of B. subtilis spores as vaccine adjuvants.

O DNA de plasmídeos naturais de uma cepa de B. stearothermophilus foi clivado com a enzima de restrição Hind III e os fragmentos resultantes foram ligados com T 4 DNA ligase ao vetor pBR 322 (Bolívar et. al., 1977) que já havia sido previamente tratado com Hind III e fosfatase alcalina. A terça parte desta mistura de ligação foi usada para transformar células de E. coli HB 101. Foram obtidos cerca de 3.500 transformantes, dos quais 46% eram recombinantes. Duas cepas que mostraram caracter amilolítico consideravelmente maior que a doadora do gene continham o plasmídeo pBR 322 com uma inserção de 5.4 Kb. O mapa de restrição, tratamento com a enzima BAL 31 e, sucessivas subclonagens (Silva, E.F. et. al.,1986)mostraram que o gene que codifica e expressa a enzima amilolítica está contido em um fragmento de 2 Kb. A enzima produzida pelas células transformadas tem peso molecular de 60.000, é estabilizada por Ca+2, tem um ótimo de temperatura de 72ºC e retém 90% da atividade original após aquecimento a 85°C por 1 hora. Estes resultados, em conjunto com a análise dos produtos de hidrólise desta enzima em cromatografia de papel, sugerem que foi clonada a alfa - amilase de B. stearothermophilus em células de E. coli. Células de duas cêpas de B. subtilis, IA 289 e BD 241 foram transformadas respectivamente com os plasmídeos p USP 33.2 (Silva, E.F. et al., 1986;1987) e p BU 217 ami 2 (Silva, E.F. & Pueyo, M.T.,1988) para produzir em ambos os casos colônias fortemente amiloliticas. Os mecanismos pelos quais as 2 cêpas passaram a apresentar o fenótipo AMY + , são provavelmente diferentes. / The DNA of natural plasmids. from a B. stearothermophilus strain was cut with Hind III endonuclease and the resulting fragments were joined with T4 DNA ligase to the vector pBR 322 (Bolivar et al. , 1977), which had previously been treated with Hind III and alkaline phosphatase. One-third of the ligation mixture was used to transform E. coli HB 101 cells. It was obtained about 3.500 transformants, which included 46% recombinans. Two strains displayng amylolytic act ivity remarkably higher than the donor gene strain, harbored the plasmid pBR 322 with an insertion of 5.4 kb. The restriction map, Bal 31 treatment and successive subcloning (Silva, E.F, et al.,1986) showed that the entire gene which codifies and allows the expression of the amylolytic enzyme is contained in a 2 Kb fragment. The enzyme has a molecular weight of 60.000, is stabilized by Cata, has a temperature optimum at 72°C and retains 90% of the original activity after heating for 1h at 85°C. These features, together with the analysis of hydrolysis produts carried on paper chromatography , suggests that we succeded in cloning the amylase from B. stearothermophilus in E. coli cells. Cells from two B. subtilis strains, IQ 289 and BD 241 were transformed with the plasmid sp USP 33.2 (Silva E. F. et al., 1986 1987) and pBU 271 ami 2 (Silva, E. F. & Pueyo, M.T., 1988) , and produce in both strains, amyiolytic colonies. The methods in which the two strains have got the AMY + fenotype, may be very different.

Le cytosquelette bactérien des homologues d’actine (protéines de la famille MreB) joue un rôle majeur dans la morphogénèse cellulaire. Des homologues de MreB sont retrouvés chez la plupart des espèces bactériennes non sphériques, où ils sont essentiels pour la viabilité cellulaire. Les bactéries à Gram-positif ont généralement plusieurs isoformes. L’organisme modèle Bacillus subtilis en possède trois : MreB, Mbl et MreBH, tous trois impliqués dans la détermination de la forme de la cellule. Le postulat actuel est une organisation, des complexes de synthèse du peptidoglycane, le long des parois latérales par les filaments hélicoïdaux des MreB-like. Cependant, les mécanismes moléculaires et les protéines effectrices impliqués dans cette fonction ne sont pas encore élucidés. Par analogie avec les rôles de l’actine eucaryote, des implications dans d’autres processus cellulaires cruciaux et la présence de partenaires protéiques sont également attendus pour les actines procaryotes. Afin d’explorer les rôles des protéines MreB chez B. subtilis nous avons généré, par des criblages génomiques double hybride chez la levure, un réseau d’interaction protéine-protéine centré sur MreB, Mbl et MreBH. Une vérification systématique et drastique de toutes les interactions obtenues lors des criblages a été réalisée afin d’éliminer les faux positifs. Les interactions identifiées révèlent des liens entre les protéines MreB-like et seize protéines issues de catégories fonctionnelles variées ou de fonction inconnue. Une étude exploratoire a été menée pour huit des protéines partenaires par des approches in silico et in vivo et nous a permis de sélectionner une seule interaction à caractériser plus en détail. Nous nous sommes principalement intéressés à l’interaction physique et directe entre MreB et DapL, une protéine essentielle vraisemblablement impliquée dans la voie de biosynthèse des précurseurs du peptidoglycane, par analogie à DapE d’E. coli. La caractérisation approfondie de DapL a confirmé son essentialité dans la synthèse du peptidoglycane. Bien que l’interaction MreB-DapL ait été confirmée biochimiquement, son rôle biologique exact n’a pas été élucidé. Cependant, nous avons mis en évidence d’autres interactions entre MreB et DapG, LysA et MurE, des enzymes également impliquées dans les étapes précoces de la synthèse du peptidoglycane. L’existence de telles interactions renforce le rôle du cytosquelette MreB de B. subtilis dans l’orchestration des machineries de synthèse de la paroi cellulaire. / Bacterial actin homologues (MreB proteins) play a major role in cell morphogenesis in non-spherical bacteria. The prevailing model postulates that helical, membrane-associated MreB-like filaments organize elongation-specific peptidoglycan-synthesizing complexes along the sidewalls. However, the mechanistic details, as well as the effector proteins of MreBs morphogenetic function, remain to be elucidated. MreB proteins are also involved in DNA segregation, cell polarity, cell motility and, by analogy to eukaryotic actins, possibly in other functions that require the targeting and accurate positioning of proteins and molecular complexes in the cell. Gram-positive bacteria usually have more than one MreB isoform. Our model organism, Bacillus subtilis, has three called MreB, Mbl and MreBH. To explore the roles of the MreB cytoskeleton in B. subtilis, we used genome-wide yeast two-hybrid screens to identify proteins that physically associate with MreB, Mbl and MreBH. Stringent specificity assays were systematically performed to remove false positives and confirm the specificity of all potential interactions identified in the screens. A protein-protein interaction network centered on the three MreBs was generated which includes 16 protein partners. This interaction network provides insights into the links of MreB proteins with proteins belonging to several functional categories as well as proteins of unknown function. An exploratory study was conducted in silico and in vivo for 8 of the partner proteins identified in the network and allowed us to select one interaction for a more in-depth analysis. We next focused in the physical interaction between MreB and DapL, an essential protein presumably involved in the early steps of peptidoglycan biosynthesis. The characterization of DapL confirmed its essential role in cell wall synthesis. The MreB-DapL interaction was confirmed biochemically and we showed that MreB also associates with other proteins involved in the synthesis of the PG precursors (DapG, LysA and MurE). Together, these results suggest that B. subtilis MreB orchestrates the PG biosynthetic cytosolic machineries to achieve and maintain its rod shape.

Chez Bacillus subtilis l’expression de l’opéron mtl pour l’utilisation du mannitol est contrôlé par MtlR. MtlR est un activateur transcriptionnel qui appartient à la famille des régulateurs DeoR composé d’un domaine HTH suivi de deux PRDs, un domaine EIIBGat et un domaine EIIAMtl-like.Le mécanisme général de la régulation de l’activité de MtlR est basé sur sa phosphorylation par des composants du PTS. La phosphorylation sur la Cystéine 419 du domaine EIIBGat par P~EIIAMtl a un effet négatif majeur sur l’activité de MtlR. Par conséquent, dans un mutant mtlF où EIIAMtl est délétée MtlR est constitutivement actif.Dans cette étude nous avons mis en évidence un nouveau phénomène de régulation de MtlR impliquant la protéine du PTS, EIIBMtl.Nous avons observé que lorsque on déléte l’opéron mtl ou EIIBMtl et EIIAMtl, l’activité constitutive de MtlR dans un mutant mtlF déjà observée est abolie d’où notre hypothèse que EIIBMtl aura un effet sur l’activité de MtlR. Par des expériences de double hybride nous avons montré une interaction directe, spécifique et bidirectionnelle entre les deux protéines EIIBMtl et EIIBGatEIIAMtl-like de MtlR. D’une manière comparable à la cellule où EIIBMtl est fusionnée à la protéine EIICMtl nous avons démontré que seulement la forme EIIBMtl fusionné à la perméase EIICMtl est capable d’activer MtlR mais nous avons également démontré que ce n’est pas EIICMtl qui est essentielle à l’interaction entre EIIBMtl et MtlR mais c’est le voisinage de la membrane qui est essentielle pour l’établissement de cette interaction et l’activation de MtlRUn modèle de régulation de l’activité du régulateur MtlR est proposé. Dans ce modèle l’induction de l’opéron mtl via l’activation de MtlR requiert la phosphorylation de PRDII de MtlR par P~His-HPr, la déphosphorylation de EIIBGat de MtlR par EIIAMtl et la présence de la forme non-phosphorylée de l’EIIBMtl qui est dominante en présence du substrat inducteur, le mannitol. Ainsi, l’EIIBMtl non-phosphorylée séquestre MtlR déphosphorylé sur sa cystéine 419 à la membrane, l’active et induit l’expression de l’opéron mtl. / The Bacillus subtilis mtl operon encodes the enzymes necessary for mannitol utilization. Its expression is controlled by MtlR, a transcriptional activator belonging to the DeoR family. MtlR contains a HTH domain followed by two PTS regulation domains (PRDs), an EIIBGat domain and an EIIAMtl-like domain.The general mechanism of the regulation of MtlR activity is based on its phosphorylation by components of the phosphoenolpyruvate: carbohydrate phosphotransferase system (PTS). The phosphorylation of EIIBGat on cysteine 419 by P~EIIAMtl has a major negative effect on the activity of MtlR. The absence of EIIAMtl in a mtlF mutant therefore leads to constitutively active MtlR.In this study a new mechanism of MtlR regulation based on the interaction of the PTS component EIIBMtl with MtlR is presented.We observed that the deletion of the entire mtlAFD operon or of mtlF and only the 3’-part of mtlA (encoding the EIIBMtl domain) abolishes the constitutive MtlR activity of the mtlF mutant, suggesting that MtlR activity depends on functional EIIBMtl. By carrying out yeast two-hybrid experiments we could establish a direct, specific and bidirectional interaction between EIIBMtl and the EIIBGatEIIAMtl-like part of MtlR.Complementation of the above mutants was possible with entire MtlA, but not with the EIIBMtl domain. EIIBMtl is normally fused to the membrane protein EIICMtl; we therefore fused EIIBMtl to another membrane, which indeed restored MtlR function in the absence of EIICMtl. The EIICMtl domain is therefore not essential for the interaction between EIIBMtl and MtlR; it is rather the vicinity of the membrane which is required for the activation of MtlR.A regulation model of MtlR activity is proposed. In this model, the MtlR-mediated induction of the mtlAFD operon requires the phosphorylation of PRDII by P~His-HPr and the dephosphorylation of EIIBGat by EIIAMtl. The presence of unphosphorylated EIIBMtl, which prevails when the inducer mannitol is present, is also required. Under these conditions unphosphorylated EIIBMtl sequesters MtlR dephosphoryled on cysteine 419, but phosphorylated at His-342, to the membrane thereby activating the transcription activator, which leads to increased expression of the mtlAFD operon.

A contaminação da água e do solo por hidrocarbonetos aromáticos tem aumentado ao longo dos anos, devido ao seu uso nos mais diversos segmentos industriais. Hidrocarbonetos, tais como tolueno, são descritos como extremamente poluentes, tóxicos e potencialmente mutagénicos e carcinogénicos para os seres humanos. Os hidrocarbonetos são compostos lipófilicos difíceis de serem eliminados, contudo, estes aromáticos podem ser removidos de ambientes contaminados por meio de biorremediação utilizando bactérias produtoras de surfactante. Biossurfatantes são surfactantes principalmente produzidos por microrganismos, as quais promovem a quebra das moléculas de hidrocarbonetos, através da formação de micelas, aumentando a sua mobilidade, a biodisponibilidade e sua exposição à bactérias favorecendo a biodegradação do hidrocarboneto. A produção deste tensoativo exige meios de fermentação e oxigênio para o metabolismo microbiano. Por tanto, aeração e agitação são variáveis operacionais importantes para garantir um coeficiente de transferência de massa de oxigénio eficaz (kLa). Para esta finalidade, o kLa foi determinado experimentalmente em diferentes meios de fermentação, especificamente meio salino básico, meio de baixa salinidade, meio Bushnell-Haas e água do mar, por diversas variáveis operacionais. Ensaios foram realizados em agitador rotativo para selecionar, dentre os diferentes tipos de bactérias, nomeadamente Bacillus subtilis, Bacillus licheniformis e Bacillus megatherium, o melhor produtor de biossurfactante na presença de tolueno, nos meios de fermentação descritos acima, formulados com diferentes salinidades. A presença de tolueno inibiu o crescimento de microrganismo deslocando seu metabolismo para a produção de biossurfactante. Assim, B. subtilis foi capaz de reduzir a tensão superficial (TS) em 29,49 ± 0,55 unidades, produzindo cerca de 3,52 ± 0,06 mg/L de biossurfactante. Ao elevar o processo para um fermentador de bancada, a quantidade de tolueno no meio de baixa salinidade foi reduzido drasticamente após 12 horas de crescimento (de 45 ml para 7,43 ml), quando B. subtilis foi utilizado, reduzindo o TS em 22,6 unidades (com concentração de biossurfactante de 3,02 mg/L). Os resultados obtidos mostraram que o B. subtilis pode ser considerado um microrganismo promissor para ser utilizado na biorremediação de locais contaminados por tolueno / Contamination of water and soil by aromatic hydrocarbons has been increasing along the years, due to its use in various industrial segments. Hydrocarbons, such as toluene, are described as extremely polluting, toxic, potentially carcinogenic and mutagenic to humans. Hydrocarbons are lipophilic compounds difficult to be disposed of; however, the aromatic ones can be removed from contaminated environments via bioremediation using surfactant-producing bacteria. Biosurfactants are surfactants produced mainly by microorganisms, which promote the breaking of hydrocarbons molecules, by means of the formation of micelles, increasing their mobility, bioavailability and exposure to bacteria favoring hydrocarbon biodegradation. This tensoactive production requires oxygen and fermentation media for the microorganism metabolism. Thus, aeration and agitation are important operating variables to ensure an effective oxygen mass transfer coefficient (kLa). To this purpose, such a response was experimentally determined in this study in different fermentation media, specifically basal saline medium, low saline medium, Bushnell-Haas medium and sea water, and correlated with the above operating variables. Rotary shaker essays were performed to select, among different bacteria, namely Bacillus subtilis, Bacillus megatherium and Bacillus licheniformis, the best biosurfactant producer in the presence of toluene, in fermentative broths described above, formulated with different salinities. The presence of toluene inhibited the growth of microorganism shifting the metabolism to the production of biosurfactant. Thus, B. subtilis was able to reduce the surface tension (ST) in 29.49 ± 0.55 units producing up to 3.52 ± 0.06 mg/L of biosurfactant. Scaling up the process to a bench fermentor, the quantity of toluene in the low salinity medium was reduced drastically after 12 h of growth (from 45 mL to 7.43 mL), when B. subtilis was used, reducing the ST in 22.6 units (biosurfactant concentration of 3.02 mg/L). The results obtained showed that B. subtilis can be considered a promising microorganism to be used for the bioremediation of sites contaminated by toluene.

Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (doctoral)--Lund University, 1998. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Made available in DSpace on 2015-04-17T14:49:18Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 787297 bytes, checksum: ef844b907c7df9d6b79a546d0a5cdc3b (MD5) Previous issue date: 2009-09-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The carciniculture is an important economic activity for Brazil, basically in the farming of a specific shrimp species (Litopenaeus vannamei). This species has shown in the last years an unsatisfactory performance due to problems caused by illnesses. That has been increasing the interest for the farming of native species like the Farfantepenaeus subtilis which has a better resistance to illnesses, besides being tolerant to several salinity variations they also have an availability of adult females and post larvae and a facility for reproduction in confined places. The nutrition of this species has to be better studied, like the necessities of vitamins A, E and C in these animals s diets. As well as knowing the stability of these vitamins in the processing, storage and handling of this diet. This study consisted of a formulation of eight diets with different levels of vitamins A, E and C and a control diet (with no vitamins). The vitamins were quantified right after the storage period (60 days) to evaluate the losses. The shrimps of the Farfantepenaeus subtilis species were fed with these diets for thirty days, in which it was evaluated the biomass gain and the survival rate. The major vitamin losses were of retinol, α-tocopherol, and ascorbic acid, respectively. The major survival rates (100%) were observed in the R1 and R4 diets which received different levels of vitamin E (184 e 364 UI/Kg), respectively. / A carcinicultura é uma atividade economicamente importante para o Brasil, sendo baseada praticamente no cultivo de uma espécie de camarão (Litopenaeus vannamei). Esta espécie nos últimos anos tem mostrado desempenho insatisfatório devido aos problemas causados por enfermidades. Isso vem despertando o interesse pelo cultivo de espécies nativas como o Farfantepenaeus subtilis que possui uma resistência maior as enfermidades, além de ser tolerante a amplas variações de salinidade, tem disponibilidade de fêmeas maduras e póslarvas e a facilidade de reprodução em ambientes confinados. A nutrição da espécie Farfantepenaeus subtilis precisa ser melhor estudada, como as necessidades de vitaminas A, E e C nas dietas destes animais. Assim como conhecer a estabilidade destas vitaminas frente ao processamento da dieta e ao armazenamento e manejo. O estudo consistiu na formulação de oito dietas com diferentes níveis de vitaminas A, E e C e uma dieta controle (sem vitaminas). As vitaminas foram quantificadas logo após o processamento das dietas e após período de armazenagem (60 dias) para avaliar as perdas. Os camarões da espécie Farfantepenaeus subtilis foram alimentados com estas dietas durante trinta dias, onde foram avaliados o ganho de biomassa e a taxa de sobrevivência. As maiores perdas vitamínicas foram de retinol, α-tocoferol e ácido ascórbico, respectivamente. As maiores taxas de sobrevivência (100%) foram observadas no tratamento R1 e R4 que receberam diferentes níveis de vitamina E (184 e 364 UI/Kg) respectivamente.

A indústria da construção civil é conhecida como umas das atividades econômicas que causam os maiores impactos ambientais desde o processo de extração da matéria prima até a produção dos produtos, incluindo o transporte e manutenção do ambiente construído. A produção de um dos seus principais componentes, o cimento, é o maior contribuinte para a emissão de gases de efeito estufa, principalmente devido a queima de combustíveis fósseis. Por este motivo, pesquisas na área de biotecnologia sustentável são conduzidas para diminuir e até mitigar os efeitos danosos provocados pelos fatores que compõem a construção civil. Dentre estas pesquisas destacam-se as que se baseiam na Biomimética, que é uma ciência que busca na Natureza as soluções tecnológicas para os problemas que os desenvolvimentos humanos geralmente apresentam: a geração de resíduos poluentes, uso de produtos químicos tóxicos e processos que operam com energia e pressão elevadas. Com base nos conceitos biomiméticos, este trabalho se propôs a estudar a biomineralização, que é um processo que ocorre na Natureza a milhares de anos e é responsável pela formação de muitas estruturas biomineralizadas tanto no ambiente terrestre como aquático. A biomineralização é um fenômeno provocado pela ação de diversas espécies de microrganismos que durante o processo de obtenção de energia reciclam minerais presentes no solo e na água e os precipitam na forma de sais inorgânicos. Este material precipitado age como agente ligante de partículas como no caso de formações geológicas (estromatólitos) ou exoesqueletos de animais marinhos, por exemplo. Neste estudo foi avaliado a biomineralização por biodeposição de carbonato de cálcio precipitado na presença da espécie de bactéria ureolítica (Bacillus subtilis) em ensaios em escala laboratorial utilizando corpos de prova de areia, argamassa e concreto. Os corpos de prova em areia e argamassa foram observados em MEV e EDS permitindo a identificação de células de microrganismos, formação de biofilme e provável formação de cristais de carbonato de cálcio na região de biofilme. Os corpos de prova de concreto foram utilizados para avaliar as consequências da biodeposição na absorção de água por capilaridade do material. Resultados indicam redução de 20% na absorção de água por capilaridade. Com os resultados obtidos é possível concluir que a técnica de biodeposição pode ser uma alternativa ao tratamento superficial de estruturas de concreto, contudo requer estudos posteriores de aplicação técnica e viabilidade econômica. / The construction industry has been known as one of the economic activities that cause the major environment impacts since the process of raw material extraction until the products manufacturing including transport and maintenance of the built environment. The production of one of the main compounds, the cement, is the largest contributor to the greenhouse gas emissions, mainly due to burn fossil fuels. For this reason, researches in sustainable biotechnological area are conducted to minimize and even mitigate the damaging effects either promoted by construction industry factors. Among these ones, it stands out researches based on Biomimetic, which is a science that seeks in Nature the technological solutions for problems that human’s development usually presents: the generation of pollutant residues, the use of toxic chemicals and process that operates in high pressure and energy. Based on biomimetic concepts this research proposes to study the biomineralization, which is a process that has occurred in the Nature for thousands of years and it is responsible for the formation of many structures either in soil and water environments. The biomineralization is a phenomenon caused by several specimens of microorganisms that during the process of obtaining energy, they recycle minerals presents at soil and water inducing precipitation as inorganic salts. This precipitated material works as a binder of particles similar to geologic formations (stromatolites) or exoskeleton of sea animal for example. In this study the biomineralization was evaluated through biodeposition of precipitated calcium carbonate by specimen of ureolytic bacteria (Bacillus subtilis). Essays were held using samples made by sand, mortar and concrete. The samples made by sand and mortar were observed at MEV and EDS, allowing the identification of microorganism cells, biofilm formation and probable formation of calcium carbonate crystals at biofilm region. The concrete samples were used to evaluate the consequences of biodeposition on water absorption by capillarity of the material. The results show reduction of 20% on water absorption by capillarity. According the results achieved it possible to conclude that the biodeposition technique can be an alternative to superficial treatment for concrete structures. However, it will be required more studies to evaluate technical application and economical availability.