C'est essentiellement sur les bactéries libres que portent les études récentes en écologie microbienne d'eau douce, et seulement quelques études ont concerné les communautés bactériennes attachées. Dans cette étude basée sur l'analyse des séquences du gène 16SARNr, la diversité des communautés bactériennes attachées ainsi que de la fraction libre a été étudiée sur deux systèmes d'eau douce ; un lac mésotrophe (le lac du Bourget) et un lac hypereutrophe (le lac Villerest). La diversité des Actinobacteria, Betaproteobacteria et Verrucomicrobia libres et attachées a été étudié en relation avec les variables environnementales, dans le lac du Bourget pendant deux périodes à dominances contrastées de phytoplancton. L'analyse des résultats a montré une différence au niveau phylogénétique entre les communautés bactériennes attachées et libres des trois groupes de bactéries étudiées. Le clade betaI, dominait les Betaproteobacteria des fractions libres et attachées, avec 57,8% de la totalité des unités taxinomiques opérationnelles (OTUs). Pour les Actinobacteria, le groupe d'acIV a été détecté comme le plus abondant, suivi par acI avec respectivement 45% et 25% du total des OTUs. De même, les groupes Verrucomicrobia d'eau douce, à savoir CREPA29, FukuN18, CL120-10 sont apparus comme les plus importants, avec 22,3%, 16,15% et 14,61% des OTUs respectivement. Cette étude a permis de définir 15 nouveaux clades putatifs représentant la diversité bactérienne d'eau douce des Betaproteobacteria (lbI-lbVIII), Actinobacteria (acLBI) et Verrucomicrobia (CRE-PA29, FukuS27, BourFI-BourFIV). Par ailleurs, 12 groupes représentant la diversité de phylogénétique des Betaproteobacteria, Actinobacteria et Verrucomicrobia contiennent exclusivement des OTUs de la fraction attachée. La dynamique saisonnière souligne les changements des phylotypes bactériens distincts pour les deux communautés attaché et libre. Les Actinobacteria dans la fraction attachée était associée avec la biomasse des Chrysophyceae et N-NO3, et les Betaproteobacteria avec la biomasse de Chlorophyceae et de la richesse du phytoplancton tandis que les Verrucomicrobia de cette même fraction ont semblé être principalement influencés par la richesse du phytoplancton, l′abondance des rotifères et les nutriments inorganiques (N-NO3, SiO2). D'autre part, dans les communautés libres, peu de clades d'actinobacterie dépendent des nutriments ou du phytoplancton, alors que les Betaproteobacteria et Verrucomicrobia ont été principalement associés avec les paramètres biologiques (i.e. phytoplancton et copépodes). Pendant le bloom des cyanobacteries (Microcystis sp.) dans le lac Villerest, les Betaproteobacteria, Gammaproteobacteria, Alphaproteobacteria, Bacteroidetes et Actinobacteria ont été détectés comme taxa dominants dans les banques de clones du gène 16S ARNr. Toutefois Verrucomicrobia et Deinococcus-Thermus sont apparus relativement moins abondants dans les deux fractions, tandis que,Gemmatimonadetes, Acidobacteria, Chloroflexi, Planctomycetes, Deltaproteobacteria, Firmicutes et Op11 sont apparus comme des phyla mineurs dans la banque de clones des communautés bactériennes attaché et libre. Les Betaproteobacteria (n=118) attachées sont apparus comme le groupe dominant, suivi par Gammaproteobacteria (n=74) et Bacteroidetes (n=52). L'analyse phylogénétique des séquences obtenues pour la banque de clone de la fraction libre a montré que la plupart des OTUs appartiennent à Betaproteobacteria (n=192), suivi par Bacteroidetes (n=132) et Actinobacteria (n=61). Tandis que les Gammaproteobacteria (n=42) et Alphaproteobacteria (n=42) sont présents dans des proportions égales dans la banque de clones du 16S ARNr libre. (...) / The free-living bacteria point of view dominates in recent research of freshwater microbial ecology, only a few studies have focused on attached bacterial communities. In present study, based on 16S rRNA gene sequences, diversity of attached and free-living bacterial community was investigated from two freshwater aquatic systems ; a mesotrophic lake Bourget and a hypereutrophic lake Villerest. The diversity of attached and free-living Actinobacteria, Betaproteobacteria and Verrucomicrobia, in relation to environmental variables was investigated from lake Bourget during two contrasting periods of phytoplankton dominance. Comparison analyses showed a phylogenetic difference between attached and free-living bacterial communities of all three studied bacterial groups. The betaI, appeared as most dominant among all clades representing phylogenetic diversity of freshwater Betaproteobacteria, for both attached and free-living fractions, contributing to 57.8% of of the total retrieved opertational taxonomic units (OTUs). For Actinobacteria, the acIV cluster was detected as dominant, followed by acI accounting for 45% and 25% of the total retrieved OTUs respectively. Similarly, freshwater Verrucomicrobia cluster namely, CRE-PA29, FukuN18, CL120-10 appeared as dominant, comprising 22.3%, 16.15% and 14.61% of the total retrieved OTUs respectively. This study allowed defining 15 new putative clades representing the freshwater bacterial divesity of Betaproteobacteria (lbI-lbVIII), Actinobacteria (acLBI) and Verrucomicrobia (CRE-PA29, FukuS27, BourFI-BourFIV). In addition, 12 clusters representing the phylogenetic diversity of Betaproteobacteria, Actinobacteria and Verrucomicrobia were exclusively comprised of OTUs from the attached fraction. The seasonal dynamics of environmental variables have been reflected as changes in distinct bacterial phylotypes for both attached and free-living communities. The attached bacterial communities of Actinobacteria showed affiliation with Chrysophyceae biomass and N-NO3, while attached Betaproteobacteria were affiliated with biomass of Chlorophyceae and phytoplankton richness. Similarly attached verrucomicrobial communities appeared to be mainly influenced by phytoplankton richness, rotifers abundances and inorganic nutrients (NNO3,SiO2). On the other hand, within free-living communities, few actinobacterial clades were found to be dependent on either nutrients or phytoplankton communities, whereas Betaproteobacteria and Verrucomicrobia were mainly associated with biological parameters (i.e. phytoplankton and copepods communities). In another study during a cyanobacterial (Microcystis sp.) bloom from lake Villerest, Betaproteobacteria, Gammaproteobacteria, Alphaproteobacteria, Bacteroidetes and Actinobacteria were detected as prevalent taxa among the 16S rRNA gene clone libraries, however, Verrucomicrobia and Deinococcus-Thermus appeared as comparatively less abundant bacterial groups in both fractions. Whereas, Gemmatimonadetes, Acidobacteria, Chloroflexi, Planctomycetes, Deltaproteobacteria, Firmicutes and Op11 were appeared as minor phyla in clone libraries of attached and free-living bacterial communities. For attached bacterial communities Betaproteobacteria (n=118) appeared as most dominant group, followed by Gammaproteobacteria (n=74) and Bacteroidetes (n=52). The phylogenetic analysis of the sequences obtained for the clone library from free-living fraction showed that most of the OTUs belonged to Betaproteobacteria (n=192) followed in decreasing order by Bacteroidetes (n=132) and Actinobacteria (n=61) whereas Gammaproteobacteria (n=42) and Alphaproteobacteria (n=42) appeared in equal proportion in free-living 16S rRNA clone libraries. (...)

No description available.

Made available in DSpace on 2014-12-17T15:54:59Z (GMT). No. of bitstreams: 1 MariaLQM_DISSERT.pdf: 3983239 bytes, checksum: a66a02095a5da5b98abfbe02d2096424 (MD5) Previous issue date: 2012-02-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Water is considered an essential right to life, besides being a determinant of economic development and social welfare, represented by both the quantity available, and the quality. In semi-arid Northeast, droughts occurring on a regular basis combined with human activities, aggravate the situation regarding the conservation of water resources in this area. To alleviate this condition is common to construction of artificial reservoirs, such as reservoirs and dams. As in natural aquatic environments, these reservoirs are potential sites for the proliferation, growth and development of diverse biological communities, whether of animals, plants and microorganisms. Research on the composition and ecology of these communities, especially microbial, are still restricted. One of the least studied groups in these environments are free-living protozoa, which over time have been neglected and after discoveries about its various functions in the aquatic ecosystem are beginning to receive more attention from scholars. They are, in quantitative terms, the most important consumers of microorganisms (mainly bacteria and algae) in aquatic environments, and therefore control the abundance of these. They may therefore influence the structure of the aquatic food chain in terms of species composition, abundance, biomass and biodiversity. Despite the recognition of the importance of protozoa in the final of the trophic transfer in aquatic environments, there are few data and, in general, are still precarious knowledge of them. Given the importance of protozoa in aquatic environments and the paucity of research on this group, especially in the state of Rio Grande do Norte, the present study aimed at identifying the genus and species of free-living protozoa that are present in the Armando Ribeiro Gon?alves Dam as well as to relate the occurrence and dynamics of the trophic conditions in the environment in which they are inserted, in order to support the hypothesis that species that are in these environments can serve to indicate the water quality. We observed the presence of 65 taxa of free-living protozoa, of which 29 were identified at the species level. There was a similarity space in taxonomic composition of protozoa, suggesting a possible regulation of this type of community for limnological variables other than those studied in this work (chlorophyll a, pH, temperature). Although it was aimed to analyze the conceptions of teachers and students from nearby towns Dam Armando Ribeiro Gon?alves, on issues relating to water quality and the role of protozoa. For this, we applied questionnaires with teachers and pupils of public schools of San Rafael and Itaj?. It was concluded that teachers and students recognize the multi-dam Armando Ribeiro Gon?alves, although unaware of important aspects of the dynamics and ecology of this environment. Conceptions of teachers and students are matched at various times, especially with regard to waterborne diseases. In an attempt to identify possible misconceptions about the knowledge of the protozoa, assuming that these organisms have neglected their ecological role, and are seen as only, disease, a study was done with teachers and students, following a particular methodology that allowed look so clear and precise results. It was clear that knowledge about the free-living protozoa is still quite limited. The alternative conceptions that were found show a direct relation of protozoans and diseases. From the data obtained by these studies, we planned a series of science communication activities, environmental education and health education in schools close to study environments in order to promote a didactic transposition of accumulated knowledge about these organisms, favoring continuing education of teachers and the increase of information to the local community through the knowledge of biodiversity and ecology of these organisms. Moreover, the results found in this study and reflections on it that led to propose the elaboration of a book Readers with an emphasis on the group of freeliving protozoa in the populations for use in public schools in the region where it was developed the semiarid work / A ?gua ? considerada um bem imprescind?vel ? vida, al?m de ser um fator condicionante do desenvolvimento econ?mico e do bem-estar social, representado tanto pela quantidade dispon?vel, como pela qualidade. No semi?rido nordestino, as secas que ocorrem de forma peri?dica aliada a atividades antr?picas, agravam a situa??o da conserva??o dos recursos h?dricos nessa localidade. Para amenizar essa condi??o ? comum a constru??o de reservat?rios artificiais, como a?udes e barragens. Assim como nos ambientes aqu?ticos naturais, estes reservat?rios s?o locais prop?cios para a prolifera??o, crescimento e desenvolvimento de diversas comunidades biol?gicas, seja de animais, vegetais e de microrganismos. As pesquisas sobre a composi??o e ecologia dessas comunidades, sobretudo as microbianas, ainda s?o restritas. Um dos grupos menos estudados nesses ambientes s?o os protozo?rios de vida livre, que ao longo do tempo foram negligenciados e depois de descobertas sobre suas variadas fun??es no ecossistema aqu?tico come?am a receber mais aten??o por parte dos estudiosos. Eles s?o, em termos quantitativos, os mais importantes consumidores de microrganismos (principalmente algas e bact?rias) nos ambientes aqu?ticos, e, por isso controlam a abund?ncia destes. Eles influenciam, portanto, a estrutura da cadeia alimentar aqu?tica em termos de composi??o de esp?cies, abund?ncia, biomassa e biodiversidade. Apesar do reconhecimento da import?ncia dos protozo?rios no balan?o final das transfer?ncias tr?ficas em ambientes aqu?ticos, existem poucos dados e, de um modo geral, s?o, ainda, prec?rios os conhecimentos sobre eles. Tendo em vista a import?ncia dos protozo?rios em ambientes aqu?ticos e a escassez de pesquisas relacionadas a este grupo, sobretudo no Estado do Rio Grande do Norte, o presente estudo teve - como objetivo identificar os g?neros e esp?cies de protozo?rios de vida livre que est?o presentes na Barragem Armando Ribeiro Gon?alves, bem como relacionar a ocorr?ncia e a din?mica destes com as condi??es tr?ficas do ambiente no qual est?o inseridos, com o intuito de corroborar a hip?tese de que as esp?cies que est?o nesses ambientes podem servir para indicar a qualidade da ?gua. Registrou-se a presen?a de 65 t?xons de protozo?rios de vida livre, dos quais 29 foram identificados em n?vel de esp?cie. Observou-se uma similaridade espacial na composi??o taxon?mica dos protozo?rios, sugerindo-se uma poss?vel regula??o desse tipo de comunidade por outras vari?veis limnol?gicas diferentes daquelas estudadas nesse trabalho (clorofila-a, pH, temperatura). Ainda objetivou-se analisar as concep??es de professores e alunos, das cidades pr?ximas da Barragem Armando Ribeiro Gon?alves, sobre as tem?ticas relativas ? qualidade de ?gua e do papel dos protozo?rios. Para isso, foi aplicado question?rios com professores e alunos de escolas estaduais de S?o Rafael e Itaj?. Concluiu-se que os professores e alunos reconhecem as m?ltiplas funcionalidades da Barragem Armando Ribeiro Gon?alves, apesar de desconhecerem aspectos importantes da din?mica e ecologia desse ambiente. As concep??es de professores e alunos se igualaram em v?rios momentos, principalmente no tocante ?s doen?as de veicula??o h?drica. Na tentativa de identificar poss?veis concep??es alternativas sobre o conhecimento dos protozo?rios, partindo da hip?tese que esses organismos t?m seu papel ecol?gico negligenciado, e s?o vistos como, somente, transmissores de doen?as, foi feito um estudo com professores e alunos, seguindo determinada metodologia que permitiu analisar de forma clara e precisa os resultados. Ficou claro que o conhecimento sobre os protozo?rios de vida livre ?, ainda, bastante limitado. As concep??es alternativas que foram evidenciadas mostram uma rela??o direta de protozo?rios e doen?as. A partir dos dados obtidos por todos esses estudos, planejou-se uma s?rie de atividades de divulga??o cient?fica, educa??o ambiental e educa??o em sa?de nas escolas pr?ximas aos ambientes de estudo com o intuito de promover uma transposi??o did?tica do conhecimento acumulado sobre esses organismos, favorecendo a forma??o continuada de professores e o incremento de informa??es ? comunidade local por meio do conhecimento da biodiversidade e ecologia desses organismos. Al?m disso, os resultados encontrados neste estudo e as reflex?es feitas sobre ele levaram a que se propusesse a elabora??o de um livro paradid?tico com ?nfase sobre o grupo dos protozo?rios de vida livre para uso junto ?s popula??es de escolas p?blicas da regi?o semi?rida onde foi desenvolvido o trabalho

Made available in DSpace on 2014-12-17T15:55:02Z (GMT). No. of bitstreams: 1 WellingtonSLJ_DISSERT.pdf: 3368256 bytes, checksum: e1e3e514061bb4417f8c184646d513ee (MD5) Previous issue date: 2013-03-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The vast hidric wealth of Brazil gets its watersheds more susceptible to impacts that compromise the water quality, affecting the ecosystem stability of aquatic environments. The decrease in the quality of water resources also results in a decrease of its multiple uses, especially in tourist areas of the coast, where the continuous flow of people to these sites increases even further the probability of inappropriate behavior of both tourists and local residents. Studies regarding the microbiological communities are still scarce, especially on the free-living protozoa that play unique roles in the food chain of aquatic ecosystems. Due to the large role played by this group of microorganisms in aquatic environments, the present study aimed at identifying the genus and species of free-living protozoa present in two sections of the Pium River, east coast of Rio Grande do Norte, making an association between the its occurrence and trophic conditions of the environment in which they are, also checking the bioindicator capacity of these organisms in water quality. It also aimed to conduct a survey with students to identify the main difficulties regarding the knowledge of free-living protozoa and hydric transmission diseases in two public schools near the river studied in the Pium district, county of Parnamirim. The survey was analyzed by means of questionnaires at both schools. Students identified several activities developed Pium river, highlighting its multifunctionality and importance to the region. A total of 76 taxa of free-living protozoa was recorded, of these, 33 were ciliates, 19 flagellates and 24 sarcodia. The spatial and temporal patterns of these organisms to both points studied revealed the bioindicator potentiality of some effective species identified. However, knowledge about the free-living protozoa proved quite lagged, presenting misconceptions that show them as pathogenic organisms exclusively, totally disregarding their ecological role. In order to remedy the flaws existing in students in relation to the functional role of protozoa, workshops were planned on these microorganisms while also addressing issues related to hydric transmission diseases through lectures, recreational activities and interactive presentations. These practical activities of Science Education had the goal of bringing students the context of local water resources, aiming to promote a greater clarification regarding of the functional role of free-living protozoa in aquatic environments / A vasta riqueza h?drica do Brasil deixa suas bacias hidrogr?ficas mais suscet?veis a impactos que comprometam a qualidade da ?gua, afetando a estabilidade ecossist?mica dos ambientes aqu?ticos. A diminui??o da qualidade dos recursos h?dricos resulta tamb?m na diminui??o dos seus usos m?ltiplos, principalmente em regi?es tur?sticas do litoral, onde o fluxo cont?nuo de pessoas a esses locais aumenta ainda mais a probabilidade de comportamentos inadequados tanto dos turistas quanto dos residentes locais. Os estudos a respeito das comunidades microbiol?gicas ainda s?o escassos, principalmente as de protozo?rios de vida livre, que desempenham fun??es singulares dentro da cadeia alimentar dos ecossistemas aqu?ticos. Devido ao grande papel desempenhado por este grupo de microrganismos nos ambientes aqu?ticos, o presente estudo teve por objetivo identificar os protozo?rios de vida livre, em g?nero e esp?cie, presentes em dois trechos do Rio Pium, litoral leste do Rio Grande do Norte, fazendo uma rela??o entre a ocorr?ncia e as condi??es tr?ficas do ambiente em que se encontram. Tamb?m se objetivou realizar uma sondagem junto aos alunos para identificar as principais dificuldades quanto ao conhecimento dos protozo?rios de vida livre e doen?as de veicula??o h?drica em duas escolas p?blicas pr?ximas ao rio estudado, no distrito de Pium, munic?pio de Parnamirim. A sondagem foi analisada por meio de question?rios aplicados em ambas as escolas. Foi registrado um total de 76 t?xons de protozo?rios de vida livre, destes, sendo 33 ciliados, 19 flagelados e 24 sarcod?neos. Os padr?es espaciais e temporais desses organismos nos dois pontos estudados revelaram a potencialidade bioindicadora eficaz de algumas esp?cies identificadas. Os alunos identificaram diversas atividades desenvolvidas no Rio Pium, destacando sua multifuncionalidade e import?ncia para a regi?o. Por?m, o conhecimento sobre os protozo?rios de vida livre mostrou-se bastante defasado, apresentando concep??es alternativas que os evidenciam como organismos exclusivamente patog?nicos, desconsiderando totalmente seu papel ecol?gico primordial. Com o prop?sito de minimizar os poss?veis equ?vocos existentes nos alunos em rela??o ao papel funcional dos protozo?rios, foram planejadas oficinas did?ticas sobre estes microrganismos, abordando tamb?m temas relacionados a doen?as de veicula??o h?drica por meio de palestras, atividades l?dicas e apresenta??es interativas. Estas atividades pr?ticas de Educa??o em Ci?ncias tiveram o intuito de aproximar os alunos do contexto dos recursos h?dricos locais, almejando-se promover um maior esclarecimento sobre o papel funcional dos protozo?rios de vida livre nos ambientes aqu?ticos

V. vermiformis est une amibe libre répandue dans l'environnement et les milieux artificiels comme les réseaux d'eau chaude sanitaire (RECS). Il est maintenant bien établi qu'elle joue un rôle de réservoir pour des bactéries pathogènes, comme L. pneumophila. Le contrôle de V. vermiformis dans les RECS représente donc un enjeu sanitaire important. Les amibes libres peuvent passer d'une forme métaboliquement active (trophozoïte) à une forme de résistance, le kyste, lorsque les conditions sont défavorables ce qui leur confère une résistance aux traitements. Malgré la haute prévalence de V. vermiformis dans les RECS, les processus de différenciation et la résistance de ses kystes aux traitements n'ont été que peu étudiés. Nous avons donc investigué les changements morphologiques et ultrastructuraux qui s'opèrent lors de l'enkystement et désenkystement de V. vermiformis. Il en ressort que l'enkystement est un phénomène rapide (9 h) qui conduit à la formation de kystes entourés d'une paroi double couche. Lors du désenkystement, les trophozoïtes n'émergent pas à travers un ostiole comme c'est le cas chez Acanthamoeba. Puis, nous avons étudié l'effet des conditions environnementales et de la concentration cellulaire sur l'enkystement. Nous avons observé que plus la concentration cellulaire est élevée plus l'enkystement est rapide, ce qui suggère l'existence de mécanismes de communication intercellulaire. Enfin, nous avons étudié la résistance des kystes aux traitements utilisés dans les RECS et aux protéases. Ces traitements étaient efficaces, in vitro, pour inactiver les kystes de V. vermiformis. Ces travaux ont permis d'apporter des connaissances de bases sur les processus de d / Vermamoeba vermiformis is a free-living amoeba (FLA) widespread in the environment and artificial environments such as hot water networks. It is now well established that it acts as a reservoir for many pathogenic bacteria, such as Legionella pneumophila. The control of V. vermiformis in artificial environments represents an important health issue. FLA can turn from a metabolic active form (trophozoite) to a resistance form, called cyst, when conditions are unfavorable. Cysts are more resistant to treatments. Despite the high prevalence of V. vermiformis in hot water networks, the processes of differentiation and the resistance of cysts to disinfection treatments have been poorly studied. Therefore we investigated morphological and ultrastructural changes occurring during encystment and excystment of V. vermiformis. It appears that encystment is a fast process (9 h) which leads to the formation of cysts surrounded by a double-layered wall. During excystment, trophozoites do not emerge through an ostiole as is the case with Acanthamoeba. Then, we studied the effect of environmental conditions and cell concentration on encystment. We observed that the higher cell concentration was, the faster the encystment was, which suggests the existence of intercellular communication. Finally, we studied the resistance of cysts to conventional disinfection treatments used in hot water networks and to innovative treatment with proteases. These treatments were effective, in vitro, to inactivate V. vermiformis cysts. This work provides new finding regarding differentiation processes and cysts resistance of V. vermiformis, a free-living amoeba poorly studied.

Dermatophytes (order Onygenales, Ascomycota) are microscopic filamentous keratinophilic fungi that can cause skin infections known as dermatophytosis. The most diverse but not very studied genus Arthroderma has been revised recently (Míková 2018) which was essential for further research. This genus comprises mostly species with a supposed reservoir in soil. Lack of information about their ecology and frequent isolation of some species from the hair of free- living mammals (mainly rodents) may testify a strong host association. Rodents could thus represent the hidden reservoir of this species. For this thesis, I have chosen three ecologically distinct rodent species: Mus musculus, Apodemus flavicollis, and Clethrionomys glareolus. I obtained the material by brushing the hair of asymptomatic individuals and used this material for cultivation on selective medium. I identified the isolates of dermatophytes (n = 30) using molecular methods. I used sequences of three highly variable loci (ITS, tubb a tef1α) to incorporate these isolates in the phylogenetic analysis based on the monography of the genus Arthroderma (Míková 2018). I characterized the phenotype of selected strains based on morphological and physiological data including the ability to utilize keratin and the production of siderophores. The...

Wir fanden konservierte molekulare Signaturen der Regulation durch Δ7-DA und Ascarosid bei Dauer- und infektiösen Larven. Danach wurde die hohe Konservierung durch unsere Analyse in Dauer- und Postdauer-Stadium zwischen den zwei nah verwandten freilebenden Arten C. elegans und C. briggsae identifiziert. Das heißt, dass die relative Veränderung auf mRNA- oder Protein- Ebene zwischen zwei Arten stark korreliert ist. Aber die relative Veränderung innerhalb derselben Art zeigt keine hochgradige Korrelation zwischen mRNA- und Protein-Ebene. Unsere Ergebnisse zeigen in C. elegans Dauerlarven die signifikante Reduzierung der RNA-Mengen in 20 Stoffwechselwegen. Im Gegensatz dazu speicherten Dauerlarven reichlich RNA-Mengen in GO Termen wie Ribosome und Aminoacyl-tRNA biosynthesis. Auf Protein-Ebene sind die Stoffwechselwege von Proteinsynthese und Proteinverarbeitung im endoplasmatischen Retikulum in Dauerlarven herunterreguliert und GO Terme wie Lysosome sind hochreguliert. Durch die Zeitreihenanalyse der Proteom-Remodellierung der molekularen Signaturen beim Austritt aus dem Dauer-Stadium fand wir, dass GO Terme wie metal ion binding signifikant herunterreguliert sind und der Proteinabbau hochreguliert ist. Unsere Ergebnisse vom pSILAC Experiment deuten an, dass die Proteine für Energieerzeugung und Chaperone/Proteinfaltung beim Daueraustritt schnell verbraucht sind und wieder hergestellt werden. Zum Schluss haben wir als Erste den popomR-Assay in C. elegans etabliert und ein Screening der vermeintlichen Proteinbindestellen auf poly-A-RNA durchgeführt, um in der Zukunft die konservierten Mechanismen der post-transkriptionellen Regulation durch RBPs im Dauer-Stadium zu analysieren. / We found the conservation of molecular signatures by regulating with Δ7-DA and Ascarosid in dauer larvae and infective larvae. Then by our comparative analysis, the high degree of conservation between two closely related free-living species C. elegans and C. briggsae was identified in dauer and post-dauer stages. This means that the relative changes are strongly correlated on the mRNA or the protein level between two species. But the relative changes in the same species don’t show any strong correlation between the mRNA and the protein levels. Our results showed a significantly reduced amount of RNA in 20 metabolic pathways in C. elegans dauer larvae. In contrast, dauer larvae stored a large amount of RNA in GO terms such as ribosome and aminoacyl-tRNA biosynthesis. On the protein level, the metabolic pathways of protein synthesis and protein processing in endoplasmic reticulum were downregulated in dauer larvae and the term of lysosome was up-regulated. Due to time course analysis for proteome remodeling of molecular signatures during exit process from dauer stage, we found that GO terms such as metal ion binding were significantly downregulated during dauer exit and at the same time the protein degradation was up-regulated. Our results of pSILAC experiment suggest that the proteins for energy generation and chaperone/protein folding are quickly spent and rebuilded during dauer exit. Finally, we were the first to establish the popomR assay in C. elegans and performed a screening of the putative protein binding sites on poly-A RNA to analyze the conserved mechanisms of post-transcriptional regulation by RBPs in dauer larvae in the future.

The effect of a free-living stage in host-parasite coevolution: a skink mite phylogenetic study in New Zealand. During the last decade, phylogenetic trees have even been used to compare ecologically related taxa such as parasites and their hosts, and are used to determine their level of coevolution or reciprocal adaptation in time. Diverse coevolutionary events have been detected for this ecological association, where generally the parasite has been regarded as one that feeds exclusively on the host and is likely to cospeciate with it. A different coevolutionary pattern might occur when the parasite has a free-living stage in its life cycle, in which the parasite may have the opportunity to abandon its host and successfully colonise a new species (host-switching) making cospeciation less likely. Many New Zealand skinks are infested with a parasitic mite, Odontacarus sp. (Prostigmata: Leeuwenhoekiidae), which becomes free-living as an adult. The genetic variation of these mites found on four hosts was analyzed for host- parasite coevolutionary events. The hosts were the McCann’s skink and the common skink in coastal Birdling Flat, Canterbury, plus these species and the Grand and Otago skinks in Macraes Flat, Central Otago, South Island, New Zealand. The genetic variation of fast evolving nuclear Internal Transcribed Spacers 2 and mitochondrial Cytochrome c Oxidase I in Odontacarus mites found on these hosts was determined by PCR and DNA sequencing and phylogenetic trees were built using the computer programs PAUP*4 and MrBayes 3. The results show that mite haplotypes only had a significant geographical division and no host-related differences. In Birdling Flat, the COI haplotypes were represented in two groups that infested both regional hosts and had 5.7 % divergence. The same individual mites belonged to a single ITS 2 haplotype, thus indicating a historical geographical division between two populations that now interbreed successfully. The Macraes Flat mites were divided into two COI haplotypes with 2.4% divergence and internal nodes, which showed greater genetic variability than the Birdling Flat populations. The Macraes Flat mites formed two ITS 2 haplotypes with 6% divergence. This greater geographical structure of the Otago mites is probably due to the older age of the mainland area compared to the recently exposed coastal locality of Birdling Flat. The COI haplotypes from the two different regions had a mean distance of 15.5%, with an earlier divergence time than that known for the hosts. For both genes, the haplotypes from different regions had 100% bootstrap support and the parasite showed no host specificity. Mites of the different COI and ITS haplotypes were found on most of the host species that were sampled in Canterbury and Otago. The results of this study suggest that a free-living stage in a parasite’s life cycle can favour coevolutionary events such as inertia (failure to speciate) and host-switching, probably as a result of resource-tracking of the parasite. NB: Electronic files contained on CD to accompany print copy are not included with this version of the thesis.

La méiofaune joue un rôle important dans le fonctionnement des habitats benthiques à substrat meuble (ex. flux de matière) en relation avec sa production élevée, sa position trophique intermédiaire et les importants transferts d’énergie vers les niveaux trophiques supérieurs qui y sont lié. Les relations trophiques et les flux de matière organique liés à la méiofaune restent néanmoins mal connus ou peu pris en compte. Afin de mieux appréhender le rôle de la méiofaune, la structure des communautés et les relations trophiques entre les sources de nourriture et ces consommateurs ont été déterminées dans cinq habitats à substrat meuble (i.e., vasière nue, herbier, zone à sables) de la baie de Marennes-Oléron, France, et de la baie de Sylt-Rømø, Allemagne, en tenant compte des variations temporelles. Le peuplement de méiofaune s’est trouvé être dominé par les nématodes et les copépodes benthiques. Les biomasses de microphytobenthos et de matière organique du sédiment sont apparues comme étant deux facteurs structurants pour les communautés. L’utilisation combinée de différents traceurs de la matière (i.e., isotopes stables, acides gras) a démontré que le microphytobenthos et les bactéries étaient les ressources trophiques majeures de la méiofaune dans les cinq habitats étudiés. Les mesures réalisées sur la structure des communautés et les données issues des traceurs de la matière ont été implémentées dans des modèles de réseaux trophiques. Dans tous les habitats, ces modèles ont mis en évidence que le flux de carbone dominant était issu du microphytobenthos, ceci démontrant les très faibles changements de comportements alimentaires malgré les importantes différences de sources trophiques en termes de disponibilité et de production des sources de nourriture entre ces différents habitats. Tous les groupes trophiques de nématodes, à l’exception des déposivores sélectifs, étaient particulièrement sélectifs et s’alimentaient majoritairement à partir de microphytobenthos, ceci étant à l’origine d’une forte production et d’un court temps de renouvellement de la méiofaune. En conclusion, cette thèse démontre le rôle important de la méiofaune dans les habitats à substrat meuble ainsi que l’importance de la relation trophique entre le microphytobenthos et la méiofaune dans le fonctionnement de ces réseaux trophiques. / Meiofauna play an important role in ecosystem processes in soft-bottom benthic habitats, e.g. food web dynamics, related to their highproduction, their intermediate trophic position and the energy they transfer towards higher trophic levels. The trophic linkages and flows of organic matter related to the meiofauna remain poorly known or taken into account. To better assess the role of meiofauna, the community structure and trophic relationships between food sources and meiofauna were determined in five intertidal soft-bottom habitats (i.e., mudflat, seagrass bed, sandflat) of the Marennes-Oléron Bay, France, and the Sylt-Rømø Bight, Germany, taking temporal variations into account. Meiofauna communities were dominated by nematodes and benthic copepods. Biomass of microphytobenthos and of sediment organic matter were two of the major drivers of community structure. The combination of trophic markers (i.e., stable isotopes, fatty acids) demonstrated that microphytobenthos and bacteria were the major food sources of meiofauna in the five habitats. Information from community structure assessments and trophic marker analyses were implemented in food web models. In all habitats, these models demonstrated that the main flow of carbon to meiofauna originated from microphytobenthos, highlighting negligible changes in meiofauna feeding behavior besides the large differences in availability and productivity of food sources between these habitats. All trophic groups of nematodes, except for selective deposit feeding nematodes, were highly selective and mainly fed on microphytobenthos, resulting in a high production and a short turn-over time of meiofauna. In conclusion, this thesis demonstrated the important role of meiofauna in soft-bottom habitats as well as the importance of the trophic pathway from microphytobenthos to meiofauna in the functioning of these food webs.

The diploma thesis deals with the design and elaboration of the project documentation of a polyfunctional house with a café in Kyjov. The new building is located in the northern part of the city. It is a 4 floor object, partlial basement building with a saddle roof. The house is based on plain concrete slabs. The supporting peripheral and internal masonry is designed from POROTHERM brick blocks. In the cafeteria, an open layout is proposed using beams and columns. Ceiling structures are designed from the POROTHERM MIAKO system. The roof structure is designed with a truss with sheet metal cover. The perimeter walls in the 1PP are designed from blocks of loose formwork filled with concrete, which are insulated with extruded polystyrene. The building is functionally divided into 2 parts, each with its own entrance. The café is equipped with a vestibule, its own café, toilet for women and men with cabins for handicapped visitors and a background with a storeroom, dressing room and WC with a hall. The residential part consists of 4 garages and 6 apartments, 2 of which are adapted for the handicapped. The object is designed with natural ventilation. The object is barrier-free. In front of the building is proposed a parking space for 9 seats, 2 of which are designed for handicapped and 2 for apartment owners.