Analyse du métabolisme du soufre de la bactérie autotrophique acidophile Acidithiobacillus thiooxidans ATCC 19377

Les impacts environnementaux dues à l'extraction minière sont considérables. C'est l'action des microorganismes, en utilisant leur métabolisme du soufre sur les déchets miniers, qui engendre les plus grands défis. Jusqu'à présent, peu de recherches ont été effectués sur les microorganismes environnementaux pour la compréhension globale de l'action du métabolisme du soufre dans une optique de prévention et de rémédiation des impacts environnementaux de l'extraction minière. Dans cette étude, nous avons étudié une bactérie environnementale, Acidithiobacillus thiooxidans, dans le but de comprendre le métabolisme du soufre selon le milieu de culture et le niveau d'acidité du milieu. Nous avons utilisé la transcriptomique à haut débit, RNA-seq, en association avec des techniques de biogéochimie et de microscopie à électrons pour déterminer l'expression des gènes codants les enzymes du métabolisme du soufre. Nous avons trouvé que l'expression des gènes des enzymes du métabolisme du soufre chez ce microorganisme sont dépendantes du milieu, de la phase de croissance et du niveau d'acidité présent dans le milieu. De plus, les analyses biogéochimiques montrent la présence de composés de soufre réduits et d'acide sulfurique dans le milieu. Finalement, une analyse par microscopie électronique révèle que la bactérie emmagasine des réserves de soufre dans son cytoplasme. Ces résultats permettent une meilleure compréhension de son métabolisme et nous rapprochent de la possibilité de développer une technique de prédiction des réactions ayant le potentiel de causer des impacts environnementaux dus à l'extraction minière.

Evidence for two protein coding transcripts at the Igf2as locus

The insulin-like growth factor 2 antisense (Igf2as) gene is part of the Ins-Igf2-H19 imprinted gene cluster. The function of the paternally expressed Igf2as is still elusive. In our previous work, we showed that Igf2as transcripts were located in the cytoplasm of C2C12 mouse myoblast cells, associated with polysomes and polyadenylated suggesting that Igf2as is protein coding. In the present work, the protein coding capacity of Igf2as was investigated. We demonstrate for the first time the existence of a polypeptide translated from an Igf2as construct. Furthermore, an RNA-Seq analysis was performed using RNA prepared from skeletal muscles of newborn wild-type and ∆ DMR1-U2 mice to further elucidate the function of Igf2as transcripts. We found no evidence for a regulatory role of Igf2as in the imprinted gene cluster. Interestingly, the RNA-Seq analysis indicated that Igf2as plays a role in the energy metabolism, the cell cycle, histone acetylation and muscle contraction pathways. Our Igf2as investigations further elucidated that there are two distinct Igf2as transcripts corresponding to two putative ORFs.

Organic and inorganic geochemistry and archaeal community composition of hypersaline sediments from Orca Basin, RV Atlantis Expedition AT18-02

Among the most extreme habitats on Earth, dark, deep, anoxic brines host unique microbial ecosystems that remain largely unexplored. As the terminal step of anaerobic degradation of organic matter, methanogenesis is a potentially significant but poorly constrained process in deep-sea hypersaline environments. We combined biogeochemical and phylogenetic analyses as well as incubation experiments to unravel the origin of methane in hypersaline sediments of Orca Basin in the northern Gulf of Mexico. Substantial concentrations of methane (up to 3.4 mM) coexisted with high concentrations of sulfate (16-43 mM) in two sediment cores retrieved from the northern and southern parts of Orca Basin. The strong depletion of 13C in methane (-77 to -89 per mill) pointed towards a biological source. While low concentrations of competitive substrates limited the significance of hydrogenotrophic and acetoclastic methanogenesis, the presence of non-competitive methylated substrates (methanol, trimethylamine, dimethyl sulfide, dimethylsulfoniopropionate) supported the potential for methane generation through methylotrophic methanogenesis. Thermodynamic calculations demonstrated that hydrogenotrophic and acetoclastic methanogenesis were unlikely to occur under in situ conditions, while methylotrophic methanogenesis from a variety of substrates was highly favorable. Likewise, carbon isotope relationships between methylated substrates and methane supported methylotrophic methanogenesis as the major source of methane. Stable isotope tracer and radiotracer experiments with 13C bicarbonate, acetate and methanol as well as 14C-labeled methylamine indicated that methylotrophic methanogenesis was the predominant methanogenic pathway. Based on 16S rRNA gene sequences, halophilic methylotrophic methanogens related to the genus Methanohalophilus dominated the benthic archaeal community in the northern basin but also occurred in the southern basin. High abundances of methanogen lipid biomarkers such as intact polar and polyunsaturated hydroxyarchaeols were detected in sediments from the northern basin, with lower abundances in the southern basin. Strong 13C-depletion of saturated and monounsaturated hydroxyarchaeol were consistent with methylotrophic methanogenesis as the major methanogenic pathway. Collectively, the availability of methylated substrates, thermodynamic calculations, experimentally determined methanogenic activity as well as lipid and gene biomarkers strongly suggested methylotrophic methanogenesis as predominant pathway of methane formation in the presence of sulfate in Orca Basin sediments.

De morbo mucoso liber singularis ... /

Mode of access: Internet.

A report to the Governor and General Assembly on the Open Space Lands Acquisition & Development (OSLAD) grant program /

The Open Space Lands Acquisition and Development (OSLAD) grant program (525 ILCS 35/1 et. seq.), administered by the Illinois Dept. of Natural Resources, was enacted in FY86 to assist eligible local government agencies in the acquisition and/or development of lands for public outdoor recreation and resource preservation purposes.

Illinois Animal Control Act with regulations /

"An act relating to stray animal control; rabies prevention; the liability of a person owning or harboring a dog which attacks or injures a person; providing penalities for violations thereof; and to repeal Acts therein named. P.A. 78-795, approved Sept. 11, 1973, eff. Oct. 1, 1973. Title amended by P.A. 83-711, 2, approved Sept. 23, 1983, eff. Jan. 1, 1984; P.A. 87-1269, 1, eff. March 3, 1993."--p. 1.

Illinois Animal Control Act with regulations /

"An act relating to stray animal control; rabies prevention; the liability of a person owning or harboring a dog which attacks or injures a person ..."--P.3.

Illinois Animal Control Act (with regulations) /

Cover title.

Illinois Humane Care For Animals Act (with regulations) /

Cover title.

Illinois Pseudorabies Control Act with regulations /

"Illinois Revised Statutes, ch.8, par. 801 et seq."--P. 3.

Village of Holiday Hills flood damage reduction project : McHenry County, Illinois.

"This project is being done under the authority given by the Flood Control Act of 1945 (Ill. Rev. Stat. 1989, ch. 19, par. 126a et seq.)--leaf 1.

The Persian heroine, a tragedy,

"Founded on Herodotus (last book, cc. 107 seq.)"--Dict. nat. biog.

The history of the bucaniers of America ... : Exhibiting a particular account and description of Porto Bello, Chagre, Panama, Cuba, Havanna, and most of the Spanish possessions on the coasts of the West Indies, and also along the coasts of the South sea : with the manner in which they have been invaded, attempted, or taken by these adventurers /

Reprint (without illus.) of "The fourth edition", London, D. Midwinter, 1741, in which the translation of Exquemelin differed from that of the earlier editions, 1684 et seq.

Miscellanea biographica. Oswinus, rex Northumbriae. Cuthbertus, episcopus lindisfarnensis ; Eata, episcopus haugustaldensis.

Texts in Latin, prefactory material in English.

Highly accurate RNA and DNA sequencing: Application to longstanding questions in aging and cancer

Thesis (Ph.D.)--University of Washington, 2016-06