Correction to Thioarsenate Transformation by Filamentous Microbial Mats Thriving in an Alkaline, Sulfidic Hot Spring

Pyrobaculum yellowstonensis Strain WP30 Respires on Elemental Sulfur and/or Arsenate in Circumneutral Sulfidic Geothermal Sediments of Yellowstone National Park

“…Polysulfides were not detected either in sterile elemental sulfur and arsenate controls or in strain WP30 cultures grown exclusively in the presence of elemental sulfur. These results show that the formation of polysulfide species is dependent on the presence of arsenite reacting with elemental sulfur as well as the concentration of monothioarsenate (42,43). Cell morphology.…”

“…Sulfide and arsenite can serve as electron donors for other community members, including other archaea (e.g., Sulfolobales) and/or bacteria (e.g., Aquificales). Polysulfides and thioarsenates formed as secondary products of sulfur and arsenate respiration may act as electron donors or acceptors for other members of the microbial community, particularly in high-pH systems where these compounds are thermodynamically stable (28,42,43,(76)(77)(78)(79)(80). Thioarsenate concentrations of 6 M (primarily as dithioarsenate) have been measured in JCHS (20), and the formation of these species was shown to be promoted during sulfur and arsenate respiration by P. yellowstonensis under culture conditions.…”

Arsenic and the gastrointestinal tract microbiome

“…Maximum pH where arsenical sulphide precipitation might occur is ~8.0, which is still within the range found in the GIT and can be quantitative at pH 6.1 and increasing with more acidic pH (Rodriguez‐Freire et al ., ). Under neutral to alkaline conditions, abiotic As(III) 2 S 3 dissolution is rapid (Hartig and Planer‐Friedrich, ; Suess and Planer‐Friedrich, ), although transformation kinetics slow with progression from trithioarsenate As(V)S 3 to thioarsenate (As(V)S). Within temporal scales of hours (i.e., GIT transit time), As(V)S is chemically stable, even in the absence of H 2 S (Hartig et al ., ), but can be rapidly decomposed by capable microorganisms leading to As(V) with intermediate accumulation of As(III) (Hartig and Planer‐Friedrich, ).…”

Thioarsenate Formation Coupled with Anaerobic Arsenite Oxidation by a Sulfate-Reducing Bacterium Isolated from a Hot Spring

“…Traditionally, the predominant form of inorganic arsenic in aqueous environments is arsenate [As(V) as H 2 AsO 4 - and HAsO 4 2- ] and arsenite [As(III) as H 3 AsO 3 0 and H 2 AsO 3 - ] in oxic and anoxic environments, respectively (Oremland, 2003). However, recently pentavalent arsenic-sulfur species, so-called thioarsenates (AsO 4-x S x 2- with x = 1–4), have also been reported as important arsenic species in a number of sulfidic geothermal environments (Wilkin et al, 2003; Stauder et al, 2005; Planer-Friedrich et al, 2007, 2009; Härtig and Planer-Friedrich, 2012; Hug et al, 2014). For example, Hug et al (2014) found that di- ( x = 2) and tri-thioarsenates ( x = 3) represented up to 25% of total arsenic in an acidic-sulfidic hot spring in New Zealand.…”

“…Thus the aioA and arxA genes have become molecular biomarkers to study the distribution and activity of arsenite-oxidizing bacteria in natural environments (Hamamura et al, 2009, 2010, 2014; Zargar et al, 2012; Engel et al, 2013; Jiang et al, 2014; Wu et al, 2015; Hernandez-Maldonado et al, 2016). Recently, it is speculated that filamentous microbial mats might play an important role in thioarsenate transformation in an alkaline, sulfidic hot spring in Yellowstone National Park, which is the first evidence showing microbially mediated thioarsenate species transformation by (hyper) thermophilic prokaryotes (Härtig and Planer-Friedrich, 2012). A subsequent investigation showed that the thermophilic microbial mats were mainly composed of Aquificales represented by Thermocrinis spp.…”