Project description:Halohasta litchfieldiae and Halorubrum lacusprofundi are important members of Deep Lake in Antarctica, representing ~44% (the most abundance) and ~10% (the 3rd most abundance) of the lake population. Deep Lake is in the Vestfold Hills, East Antarctica (68°33’36.8S, 78°11’48.7E) and is 36 m deep, monomictic, and perennially cold (down to -20C) (DeMaere et al., 2013; Williams et al., 2014; Tschitschko et al., 2015; Tschitschko et al., 2016). In this project, using quantitative proteomics (8-plex iTRAQ labeling), proteins, pathways and cellular processes important for cold adaptation were determined for both Hht. litchfieldiae and Hrr. lacusprofundi. The data provided a new level of understanding about molecular mechanisms and regulatory networks involved in adaptation of the Antarctic haloarchaea to cold environment. DeMaere, M. Z., Williams, T. J., Allen, M. A., Brown, M. V., Gibson, J. A., Rich, J., et al. (2013) High level of intergenera gene exchange shapes the evolution of haloarchaea in an isolated Antarctic lake. Proc Natl Acad Sci USA 110: 16939-16944. Tschitschko, B., Williams, T. J., Allen, M. A., Páez-Espino, D., Kyrpides, N., Zhong, L., et al. (2015) Antarctic archaea–virus interactions: metaproteome-led analysis of invasion, evasion and adaptation. ISME J 9: 2094-2107. Tschitschko, B., Williams, T. J., Allen, M. A., Zhong, L., Raftery, M. J., and Cavicchioli, R. (2016) Ecophysiological distinctions of haloarchaea from a hypersaline Antarctic lake determined using metaproteomics. Appl Environ Microbiol 82: 3165 – 3173. Williams, T. J., Allen, M. A., DeMaere, M. Z., Kyrpides, N. C., Tringe, S. G., Woyke, T., and Cavicchioli, R. (2014) Microbial ecology of an Antarctic hypersaline lake: genomic assessment of ecophysiology among dominant haloarchaea. ISME J 8: 1645-1658.

2017-02-27 | PXD005076 | Pride

Quantitative proteomics of biofilm formation of the Antarctic archaeon Halorubrum lacusprofundi

Project description:Halorubrum lacusprofundi is an important member of Deep Lake in Antarctica, representing ~10% of the lake population (DeMaere et al., 2013). Deep Lake is in the Vestfold Hills, East Antarctica (68°33’36.8S, 78°11’48.7E) and is 36 m deep, monomictic, and perennially cold (down to -20°C) (DeMaere et al., 2013; Williams et al., 2014; Tschitschko et al., 2015; Tschitschko et al., 2016). In this project, using quantitative proteomics (8-plex iTRAQ labeling), proteins, pathways and cellular processes important for biofilm formation were determined for Hrr. lacusprofundi. The data provided a new level of understanding about molecular mechanisms and regulatory networks involved in adaptation of Hrr. lacusprofundi to biofilm formation. DeMaere, M. Z., Williams, T. J., Allen, M. A., Brown, M. V., Gibson, J. A., Rich, J., et al. (2013) High level of intergenera gene exchange shapes the evolution of haloarchaea in an isolated Antarctic lake. Proc Natl Acad Sci USA 110: 16939-16944. Tschitschko, B., Williams, T. J., Allen, M. A., Páez-Espino, D., Kyrpides, N., Zhong, L., et al. (2015) Antarctic archaea–virus interactions: metaproteome-led analysis of invasion, evasion and adaptation. ISME J 9: 2094-2107. Tschitschko, B., Williams, T. J., Allen, M. A., Zhong, L., Raftery, M. J., and Cavicchioli, R. (2016) Ecophysiological distinctions of haloarchaea from a hypersaline Antarctic lake determined using metaproteomics. Appl Environ Microbiol 82: 3165 – 3173. Williams, T. J., Allen, M. A., DeMaere, M. Z., Kyrpides, N. C., Tringe, S. G., Woyke, T., and Cavicchioli, R. (2014) Microbial ecology of an Antarctic hypersaline lake: genomic assessment of ecophysiology among dominant haloarchaea. ISME J 8: 1645-1658.

2016-12-13 | PXD004202 | Pride

Acute toxicity, bioaccumulation and effects of dietary transfer of silver from brine shrimps exposed to PVP/PEI-coated silver nanoparticles to zebrafish

Project description:Silver nanoparticles (NPs) are extensively used due to their antimicrobial activity and, therefore, their input into the ecosystem will increase. Silver can be bioaccumulated by low trophic level organisms and, then, incorporated into the food chain, reaching high level predators. The objectives of this study were to test the acute toxicity of N-vynil-2-pirrolidone/polyethylenimine (PVP-PEI) coated Ag NPs of 5 nm to brine shrimp (Artemia sp) larvae and to assess bioaccumulation and effects of silver transferred by the diet. For the later, brine shrimps were exposed to two different concentrations of Ag NPs, 100 ng/L as an environmentally relevant concentration and 100 µg/L as a likely effective concentration, in parallel with an unexposed control group and, then, used to feed zebrafish during 21 days in order to simulate two trophic levels of a simplified food web. For brine shrimp larvae, EC50 values ranged from 7.39 mg Ag/L (48 h post hatch larvae (hph) exposed for 48 h) to 19.63 mg Ag/L (24 hph larvae exposed for 24 h. Silver accumulation was measured in brine shrimps exposed to 0.1 and 1 mg/L of Ag NPs for 24 h. In zebrafish fed with brine shrimps exposed to Ag NPs, intestine showed higher metal accumulation than liver, although both organs presented the same pattern of dose and time-dependent metal accumulation as revealed by autometallography. Feeding of zebrafish for 3 days with brine shrimps exposed to 100 ng/L of Ag NPs was enough to impair fish health as reflected by the significant reduction of the lysosomal membrane stability and the presence of several histopathological conditions in the liver. Overall, results showed that Ag NPs were able to exert toxic effects on zebrafish through dietary exposure, even at an environmentally relevant concentration, which should act as concern of the need of studies in further detail about real impact of nanomaterials in the environment.

2017-03-21 | GSE90457 | GEO

Molecular Acclimation of Halobacterium salinarum to Halite Brine Inclusions

Project description:Halophilic microorganisms have long been known to survive within the brine inclusions of salt crystals, as evidenced by their pigmentation. However, the molecular mechanisms allowing this survival has remained an open question for decades. While protocols for the surface sterilization of halite (NaCl) have enabled isolation of cells and DNA from within halite brine inclusions, “-omics” based approaches have faced two main technical challenges: (1) removal of all contaminating organic biomolecules (including proteins) from halite surfaces, and (2) performing selective biomolecule extractions directly from cells contained within halite brine inclusions with sufficient speed to avoid modifications in gene expression during extraction. In this study, we present methods to resolve these two technical challenges. In addition, we apply these methods to perform the first examination of the early acclimation of a model haloarchaeon (Halobacterium salinarum NRC-1) to halite brine inclusions. Examinations of the proteome of Halobacterium cells two months post-evaporation revealed a high degree of similarity with stationary phase liquid cultures, but with a sharp down-regulation of ribosomal proteins. Low quantities of RNA from halite brine inclusions corroborate the hypothesis of low transcriptional and translational activities. While proteins for central metabolism were part of the shared proteome between liquid cultures and halite brine inclusions, proteins involved in cell mobility (archaellum, gas vesicles) were either absent or less abundant in halite samples. Proteins unique to cells within brine inclusions included transporters, suggesting modified interactions between cells and the surrounding brine inclusions microenvironment. The methods and hypotheses presented here enable future studies of the survival of halophiles in both culture model and natural halite systems.

2023-03-10 | PXD037167 | Pride

Morus alba Raw protein sequence reads

Project description:Morus alba L. Raw protein sequence reads and sequence

2024-02-08 | PXD049451 | iProX