Microbial weeds in hypersaline habitats: the enigma of the weed-like Haloferax mediterranei

Heterotrophic prokaryotic communities that inhabit saltern crystallizer ponds are typically dominated by two species, the archaeon Haloquadratum walsbyi and the bacterium Salinibacter ruber, regardless of location. These organisms behave as ‘microbial weeds’ as defined by Cray et al. (Microb Biotechnol 6: 453–492, 2013) that possess the biological traits required to dominate the microbiology of these open habitats. Here, we discuss the enigma of the less abundant Haloferax mediterranei, an archaeon that grows faster than any other, comparable extreme halophile. It has a wide window for salt tolerance, can grow on simple as well as on complex substrates and degrade polymeric substances, has different modes of anaerobic growth, can accumulate storage polymers, produces gas vesicles, and excretes halocins capable of killing other Archaea. Therefore, Hfx. mediterranei is apparently more qualified as a ‘microbial weed’ than Haloquadratum and Salinibacter. However, the former differs because it produces carotenoid pigments only in the lower salinity range and lacks energy-generating retinal-based, light-driven ion pumps such as bacteriorhodopsin and halorhodopsin. We discuss these observations in relation to microbial weed biology in, and the open-habitat ecology of, hypersaline systems.

Romance Sociolinguistics

This is a commissioned book that will be co-edited by Ayres-Bennett (Cambridge) and Carruthers (Queen's). The editors will co-write the introduction and a chapter each. There will be 27 chapters in all from scholars around the world.

Truth at 24 frames a second? A working dialogue between a film-maker and a historical consultant about the making of The Enigma of Frank Ryan

We employ a practice-based methodology based on a ‘live’ film project to explore the different ways that film-makers and historians narrate the past. Through a case-study of the production and exhibition of a drama-documentary feature-film, The Enigma of Frank Ryan, on which both authors (film-maker Bell and historian McGarry) worked respectively as director and historical consultant, we explore a range of critical issues arising from our collaboration. Through a dialogue between a director and a historian, a model of good practice between historians and film-makers emerges.