Frontiers in Extreme Microbiology is a Specialty Section of Frontiers in Microbiology.

Frontiers in Extreme Microbiology is a Specialty Section of Frontiers in Microbiology that publishes research on microbial life that flourishes or persists under permanent or periodic extreme environmental conditions. We will work to update the general understanding of extreme microbiology, from a niche specialty focused on a few exotic microorganisms and habitats, to one of the principal fields in microbiology that in itself is rapidly developing and diversifying.

Although an absolute consensus on what counts as “extreme” is hard to find, an initial approximation focuses on environmental conditions that impose physiological stress and growth limitations of increasing severity on the majority of microorganisms; those that have developed strategies and adaptations that allow them to live permanently under these conditions we term extremophiles. Among others, the best known of such extremes exist in form of permanent frost in polar and mountain regions, permanently cold deep sea environments, hot springs and deep sea vents, ultra-dry soils, such as the Atacama Desert, the deep marine and terrestrial subsurface, as well as cosmic space – the final frontier. Over the last decade, our knowledge of and interest in microbial diversity and habitat range of extremophiles has grown exponentially, and has transcended conventional disciplinary boundaries.

While extremophilic microorganisms and their habitats are an important and central topic for Frontiers in Extreme Microbiology, they are not its sole focus. Microorganisms of all types encounter naturally variable conditions that are not permanent, but remain challenging even for short time frames; examples might include the drastic changes of pH during passage through the human intestinal tract, fluctuating thermal gradients that characterize pulsating hydrothermal flow regimes, or the diurnally changing redox regimes within photosynthetic cyanobacterial mats that cycle from oxygen supersaturation during the day to sulfidic anoxia by night. Most microorganisms that undergo these shifts would perish if they were positioned permanently on the wrong side of these cycles, but they thrive within their dynamic environment. This variant of extreme environments and their microbial inhabitants – what for the lack of a better term might be called extremotolerant - is omnipresent in nature, and will be appropriately emphasized by Frontiers in Extreme Microbiology.

Last but not least, some environmental fluctuations are so severe, intense or long-lasting that microbial activity and cell metabolism are temporarily suspended, and the mode and extent of survival becomes the principal issue, as in desiccation, ionic damage, or exposure to intense radiation. Quite often, the limits of life – permanent or fluctuating regimes in nature - are fluid boundaries that may change in surprising and unforeseen ways. Frontiers in Extreme Microbiology will chart these outer reaches of life as we get to know them better over the coming years.

Frontiers in Extreme Microbiology welcomes the following tier 1 article types: Book Review, Editorial, General Commentary, Hypothesis & Theory, Methods, Mini Review, Opinion, Original Research, Perspective, Review and Specialty Grand Challenge.

All articles must be submitted directly to Frontiers in Extreme Microbiology, where they are processed by the associate and review editors of the Specialty Section.

All articles published in Frontiers in Extreme Microbiology will be subjected to the Frontiers Evaluation System after online publication. Authors of the original research articles with the highest impact, as judged by many expert readers, will be invited by the Field Chief Editor of Frontiers in Microbiology to write a prestigious Frontiers Focused Review - a tier 2 article. This is referred to as "democratic tiering". The selection is based on the reader impact over a 4-month period from the date of publication. The selected high impact articles are re-written in a review style centered on the original discovery, and aim to address the wider audience across all of Microbiology.