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The European Space Agency's EXPOSE facility, located on the outside of the International Space Station, was used to investigate the survival of cell aggregates of a cyanobacterium, Gloeocapsa sp., in space and simulated martian conditions for 531 days in low Earth orbit as part of the "Biofilm Organisms Surfing Space" (BOSS) experiments. Postflight analysis showed that the cell aggregates of the organism conferred protection against space conditions compared to planktonic cells. These cell aggregates, which consisted of groups of metabolically inactive cells that do not form structured layered biofilms, demonstrated that disordered "primitive" aggregates of sheathed cells can provide protection against environmental stress such as UV radiation. Furthermore, the experiment demonstrated that the cyanobacterial cell aggregates provided a microhabitat for a smaller bacterial co-cultured species that also survived in space. This observation shows that viable cells can "hitchhike" through space within the confines of larger protecting cells or cell aggregates, with implications for planetary protection, human health, and other space microbiology applications.

Mitteilungen des Kunsthistorischen Institutes in Florenz, Bd. 54, Nr. 2 (2010): Mitteilungen des Kunsthistorischen Institutes in Florenz

Publisher's version (útgefin grein), Four facultative anaerobic and two obligate anaerobic bacteria were isolated from extreme environments (deep subsurface halite mine, sulfidic anoxic spring, mineral-rich river) in the frame MASE (Mars Analogues for Space Exploration) project. The isolates were investigated under anoxic conditions for their survivability after desiccation up to 6 months and their tolerance to ionizing radiation up to 3000 Gy. The results indicated that tolerances to both stresses are strain-specific features. Yersinia intermedia MASE-LG-1 showed a high desiccation tolerance but its radiation tolerance was very low. The most radiation-tolerant strains were Buttiauxella sp. MASE-IM-9 and Halanaerobium sp. MASE-BB-1. In both cases, cultivable cells were detectable after an exposure to 3 kGy of ionizing radiation, but cells only survived desiccation for 90 and 30 days, respectively. Although a correlation between desiccation and ionizing radiation resistance has been hypothesized for some aerobic microorganisms, our data showed that there was no correlation between tolerance to desiccation and ionizing radiation, suggesting that the physiological basis of both forms of tolerances is not necessarily linked. In addition, these results indicated that facultative and obligate anaerobic organisms living in extreme environments possess varied species-specific tolerances to extremes, This work was supported by European Community's Seventh Framework Program (FP7/2007-2013) [grant agreement no. 607297].

The definitive detection of biosignatures in the context of astrobiological missions to Mars is not without difficulty. Could it be possible to detect biomarkers from an extinct form of life in a very ancient material? The traces of some microorganisms can be well preserved thanks to rapid mineralization of the organisms and cementation of the sediments in which they occur [1]. Thus biosignatures could be indicators of either extant or extinct life, the search for which is one of the main objectives of Mars exploration [1]. The central motivation of the MASE project (Mars Analogues for Space Exploration) is to gain knowledge about the habitability of Mars by the study of the adaptation of anaerobic life forms to extreme environments, their environmental context, and the methods used to detect their biosignatures. Within this background a fundamental target of MASE project is to improve and optimize methods for biosignature detection in samples with low biomass from certain Mars analogue sites. In this context we applied antibody multiarray competitive immunoassay to follow the evolution of specific biochemical signatures from a culture under fossilization conditions. An antibody multiarray competitive immunoassay for the simultaneous detection of compounds of a wide range of molecular sizes or whole spores and cells [2] [3] has revealed as suitable option to achieve this MASE purpose. It consists in a rapid strategy to detect a huge set of different epitopes in extracted samples by a sandwich multiarray immunoassay in a slide or LDChip (Life Detector Chip) where huge range of different antibodies are coated. In this report, we present the results from an experiment in which we followed the biochemical signatures from a growing culture of an isolate of Yersinia sp. in fresh media and in a culture growing under fossilization conditions in silica and gypsum. A decrease in the signal of relative fluorescence of antibody-antigen binding (biomarkers detected) is observed when comparing an untreated Yersinia sp. culture and those induced to mineralization at different time points.

Astrobiology seeks to understand the limits of life and to determine the physiology of organisms in order to be able to better assess the potential habitability of other worlds and improve our ability to assay them for the presence of life. To successfully achieve this we require representative microorganisms from environments on Earth that in physical and/or chemical conditions approximate to extraterrestrial environments. The most challenging of these environments with respect to the sample collection and follow on isolation and cultivation of microorganisms are anaerobic environments. Here we describe a systematic approach to this challenge and aim to provide a guideline for future fieldwork and sampling campaigns. We selected a number of anaerobic environments based on characteristics that make them analogous to past and present locations on Mars (Icelandic lakes, sulfidic springs, deep hypersaline environments, acidic iron-rich environments, and permafrost). We implemented a culturing approach to enrich organisms from these environments under anaerobic conditions using a defined medium that would allow for all organisms to be grown under identical culturing conditions m future physiological comparisons. We then isolated anaerobic microorganisms, carried out a study of their basic physiology and deposited these organisms in the DSMZ (Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH) culture collection to make them available to astrobiologists and microbiologists. This project represents the first attempt to implement a coordinated effort from the selection of extraterrestrial analog sites through to the isolation and the characterisation of organisms and their deposition within a culture collection.

The Second International Planetary Dunes Workshop took place in Alamosa, Colorado, USA from May 18�¢����21, 2010. The workshop brought together researchers from diverse backgrounds to foster discussion and collaboration regarding terrestrial and extra-terrestrial dunes and dune systems. Two and a half days were spent on five oral sessions and one poster session, a full-day field trip to Great Sand Dunes National Park, with a great deal of time purposefully left open for discussion. On the last day of the workshop, participants assembled a list of thirteen priorities for future research on planetary dune systems.

(41 .Contribución al conocimiento de Chrysomelidae). Número enero-marzo, In meinem 40.Beitrag (im Druck bei M. Villiers, .Algier) erwähnten Material aus Nigeria, aus der Umgebung von Loko, in der Provinz Munschi, am Ufergebiet des Flusses Benne, erhielt ich zwischen anderem noch 17 Cryptoceptia/us-Arten. Damals konnte ich mich wegen Fehlens neuester Literatur mit diesen Arten nicht näher beschäftigen.