Characterization of precipitates formed by H2S-producing, Cu-resistant Firmicute isolates of Tissierella from human gut and Desulfosporosinus from mine waste

Abstract

The purpose of this study was to characterize precipitates formed in anaerobic, H2S-producing cultures of two Tissierella isolates and Desulfosporosinus strain DB. The cultures were grown in Cu-containing media as part of a larger study of Cu resistance in anaerobic sulfidogens. The Tissierella strains produced H2S from peptone. Desulfosporosinus formed H2S from peptone or through dissimilatory sulfate reduction with lactate. Tissierella cultures precipitated iron phosphate, vivianite, but no crystalline phases or Cu sulfides were detected. Multiple Cu sulfides, including chalcopyrite and covellite, were detected in Desulfosporosinus cultures but vivianite was not formed. Ion microprobe spectra and electron microscopic examination showed major variation in the elemental composition and morphological differences depending on incubation conditions. Extended incubation time for at least 1-2 months increased the crystallinity of the precipitates. The results highlight biogeochemical differences in sulfide and phosphate precipitates between the two major groups of Firmicutes although they may share the same habitat including the human intestinal tract.

Characterization and Genome Analysis of the First Facultatively Alkaliphilic Thermodesulfovibrio Isolated from the Deep Terrestrial Subsurface

“…Cell morphology was observed by phase contrast microscopy using an Axio Imager A1 microscope and by transmission electron microscopy (TEM) of ultra-thin sections, as described previously (Ikkert et al, 2013). …”

“…Cells were collected at the end of stationary growth by centrifugation (16,800 g for 10 min) and air-dried. SEM-EDS was performed using a Philips SEM 515 scanning electron microscope as described previously (Ikkert et al, 2013). The presence of crystalline cellulose was analyzed by XRD using a Shimadzu XRD 6000 diffractometer with CuKa radiation (Ikkert et al, 2013).…”

“…SEM-EDS was performed using a Philips SEM 515 scanning electron microscope as described previously (Ikkert et al, 2013). The presence of crystalline cellulose was analyzed by XRD using a Shimadzu XRD 6000 diffractometer with CuKa radiation (Ikkert et al, 2013). Mineral identification was computer-assisted with the Crystallographica-Search Match and the database PDF-2.…”

An acidophilic Desulfosporosinus isolated from the oxidized mining wastes in the Transbaikal area

“…The standard sample was made of pure silicon with the known peak position required for the calibration curve (28.46°). The measurements were taken with 0.02°s tep, rate of 1° per minute, and exposure at a point of 1.2 s. Ultrathin sectioning and transmission electron microscopy were carried out as described previously (Ikkert et al, 2013).…”

Genome sequence of the copper resistant and acid-tolerant Desulfosporosinus sp. BG isolated from the tailings of a molybdenum-tungsten mine in the Transbaikal area

“…These bacteria may participate in metal detoxification by precipitating them in the form of sulfides [5]. Desulfosporosinus acidiphilus [2] and Desulfosporosinus acididurans [19], both isolated from mining environments, represent the only two validly described, moderately acidophilic sulfate-reducing bacteria.…”