Diversity and Physiologies of Acidophilic Archaea
Olga V. Golyshina, Manuel Ferrer and Peter N. Golyshin
from: Acidophiles: Life in Extremely Acidic Environments (Edited by: Raquel Quatrini and D. Barrie Johnson). Caister Academic Press, U.K. (2016) Pages: 93-106.
The majority of cultured acidophilic archaea are represented by two phyla, the Crenarchaeota and the Euryarchaeota, that inhabit sulfur-rich areas in volcanically-active regions worldwide and sulfidic deposits rich in metals, acid mine drainage systems, macroscopic growths in forms of streamers, slimes, mats and microbial stalactites. A metabolic network formed by these archaea is determined by niche adaptation and is characterized by sulfur-, hydrogen- and iron-dependency, and by the organotrophy of scavenger species and strains. Acidophily is a major trait in the organisms from the above environments and most characterised species are moderate or extreme thermophiles, though there are some exceptions. Isolation sites of acidophilic archaea are almost exclusively limited to terrestrial habitats, with marine environments being poorly explored as a reservoir for these organisms, with only one such acidophilic euryarchaeote isolated to date. The nature and mechanisms of acidophily are believed to be determined by a number of factors with special archaeal membranes and lipids being of the greatest importance. Genome analysis of a number of species of acidophilic archaea has identified certain metabolic traits that make them distinct from bacterial counterparts and suggests some unusual variants of classical pathways read more ...