TY - JOUR
T1 - Assessment of biofilm changes and concentration-depth profiles during arsenopyrite oxidation by Acidithiobacillus thiooxidans
AU - Ramírez-Aldaba, Hugo
AU - Vazquez-Arenas, Jorge
AU - Sosa-Rodríguez, Fabiola S.
AU - Valdez-Pérez, Donato
AU - Ruiz-Baca, Estela
AU - García-Meza, Jessica Viridiana
AU - Trejo-Córdova, Gabriel
AU - Lara, René H.
N1 - Publisher Copyright:
© 2017, Springer-Verlag GmbH Germany.
PY - 2017/8/1
Y1 - 2017/8/1
N2 - Biofilm formation and evolution are key factors to consider to better understand the kinetics of arsenopyrite biooxidation. Chemical and surface analyses were carried out using Raman spectroscopy, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), glow discharge spectroscopy (GDS), and protein analysis (i.e., quantification) in order to evaluate the formation of intermediate secondary compounds and any significant changes arising in the biofilm structure of Acidithiobacillus thiooxidans during a 120-h period of biooxidation. Results show that the biofilm first evolves from a low cell density structure (1 to 12 h) into a formation of microcolonies (24 to 120 h) and then finally becomes enclosed by a secondary compound matrix that includes pyrite (FeS2)-like, Sn 2−/S0, and As2S3 compounds, as shown by Raman and SEM-EDS. GDS analyses (concentration-depth profiles, i.e., 12 h) indicate significant differences for depth speciation between abiotic control and biooxidized surfaces, thus providing a quantitative assessment of surface-bulk changes across samples (i.e. reactivity and /or structure-activity relationship). Respectively, quantitative protein analyses and CLSM analyses suggest variations in the type of extracellular protein expressed and changes in the biofilm structure from hydrophilic (i.e., exopolysaccharides) to hydrophobic (i.e., lipids) due to arsenopyrite and cell interactions during the 120-h period of biooxidation. We suggest feasible environmental and industrial implications for arsenopyrite biooxidation based on the findings of this study.
AB - Biofilm formation and evolution are key factors to consider to better understand the kinetics of arsenopyrite biooxidation. Chemical and surface analyses were carried out using Raman spectroscopy, scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), glow discharge spectroscopy (GDS), and protein analysis (i.e., quantification) in order to evaluate the formation of intermediate secondary compounds and any significant changes arising in the biofilm structure of Acidithiobacillus thiooxidans during a 120-h period of biooxidation. Results show that the biofilm first evolves from a low cell density structure (1 to 12 h) into a formation of microcolonies (24 to 120 h) and then finally becomes enclosed by a secondary compound matrix that includes pyrite (FeS2)-like, Sn 2−/S0, and As2S3 compounds, as shown by Raman and SEM-EDS. GDS analyses (concentration-depth profiles, i.e., 12 h) indicate significant differences for depth speciation between abiotic control and biooxidized surfaces, thus providing a quantitative assessment of surface-bulk changes across samples (i.e. reactivity and /or structure-activity relationship). Respectively, quantitative protein analyses and CLSM analyses suggest variations in the type of extracellular protein expressed and changes in the biofilm structure from hydrophilic (i.e., exopolysaccharides) to hydrophobic (i.e., lipids) due to arsenopyrite and cell interactions during the 120-h period of biooxidation. We suggest feasible environmental and industrial implications for arsenopyrite biooxidation based on the findings of this study.
KW - Acidithiobacillus thiooxidans
KW - Arsenopyrite biooxidation
KW - Biofilm changes
KW - Glow discharge spectroscopy
KW - Surface analysis
UR - http://www.scopus.com/inward/record.url?scp=85023163477&partnerID=8YFLogxK
U2 - 10.1007/s11356-017-9619-8
DO - 10.1007/s11356-017-9619-8
M3 - Artículo
C2 - 28702905
SN - 0944-1344
VL - 24
SP - 20082
EP - 20092
JO - Environmental Science and Pollution Research
JF - Environmental Science and Pollution Research
IS - 24
ER -