Performance and bacterial community shifts during phosphogypsum biotransformation

Phosphogypsum (PG) is an industrial waste composed mainly by sulfate, turning it a suitable sulfate source for sulfate-reducing bacteria (SRB). In the present work, the capability of two SRB communities, one enriched from Portuguese PG (culture PG) and the other from sludge from a wastewater treatment plant (culture WWT-1), to use sulfate from PG was compared. In addition, the impact of this sulfate-rich waste in the microbial community was assessed. The highest efficiency in terms of sulfate reduction was observed with culture WWT-1. The bacterial composition of this culture was not significantly affected when sodium sulfate from the nutrient medium was replaced by PG as a sulfate source. Next generation sequencing (NGS) showed that this community was phylogenetically diverse, composed by bacteria affiliated to Clostridium, Arcobacter, and Sulfurospirillum genera and by SRB belonging to Desulfovibrio, Desulfomicrobium, and Desulfobulbus genera. In contrast, the bacterial structure of the community enriched from PG was modified when sodium sulfate was replaced by PG as the sulfate source. This culture, which showed the poorest performance in the use of sulfate from PG, was mainly composed by SRB related to Desulfosporosinus genus. The present work provides new information regarding the phylogenetic characterization of anaerobic bacterial communities with the ability to use PG as sulfate donor, thus, contributing to improve the knowledge of microorganisms suitable to be used in PG bioremediation. Additionally, this paper demonstrates that an alternative to lactate and low-cost carbon source (wine wastes) can be used efficiently for that purpose

Monitoring of microbial hydrocarbon remediation in the soil

Bioremediation of hydrocarbon pollutants is advantageous owing to the cost-effectiveness of the technology and the ubiquity of hydrocarbon-degrading microorganisms in the soil. Soil microbial diversity is affected by hydrocarbon perturbation, thus selective enrichment of hydrocarbon utilizers occurs. Hydrocarbons interact with the soil matrix and soil microorganisms determining the fate of the contaminants relative to their chemical nature and microbial degradative capabilities, respectively. Provided the polluted soil has requisite values for environmental factors that influence microbial activities and there are no inhibitors of microbial metabolism, there is a good chance that there will be a viable and active population of hydrocarbon-utilizing microorganisms in the soil. Microbial methods for monitoring bioremediation of hydrocarbons include chemical, biochemical and microbiological molecular indices that measure rates of microbial activities to show that in the end the target goal of pollutant reduction to a safe and permissible level has been achieved. Enumeration and characterization of hydrocarbon degraders, use of micro titer plate-based most probable number technique, community level physiological profiling, phospholipid fatty acid analysis, 16S rRNA- and other nucleic acid-based molecular fingerprinting techniques, metagenomics, microarray analysis, respirometry and gas chromatography are some of the methods employed in bio-monitoring of hydrocarbon remediation as presented in this review

Participation of microorganisms in biogeochemical processes in geological near-surface environment.

Microorganisms play key roles in the biosphere, particularly in the areas of element biotransformations and biogeochemical cycling, mineral transformations, decomposition, bioweathering, and soil and sediment formation. Direct and indirect physical, chemical and biochemical mechanisms are involved in mineral biotransformation by microbes. The role of anaerobic microorganisms and influence of their activity products on geological environmental condition in the weathering zone of lithosphere is discussed. The most important anaerobic microorganisms are sulphate-reducing bacteria (SRB) and methanogenic Archaea. These groups of microorganisms play significant role in biodegradation of organic matter and participate in formation of different kind of mineral phases e.g. carbonates and metal sulphides

Participation of microorganisms in biogeochemical processes in geological near-surface environments. Part I - Aerobic microorganisms

Microorganisms activity have large influence on composition of minerals and rocks due to biogeochemical processes in the lithosphere weathering zone. In each environment specific autochthonous microorganisms occur and knowledge of their activity and certain biochemical processes is very important in understanding the geochemical cycles of elements, minerals and organic compounds. Physical and chemical conditions of environment strongly influence the composition of bacterial communities. Depending on their properties, the activity of one group of microorganisms, may affect the chemical reactions on significant way and can moderate the direction of biogeochemical processes. The paper is focused on the role of aerobic microbial communities and products of their metabolism in biogeochemical conditions at the weathered zone

Influence of electron donors and copper concentration on geochemical and mineralogical processes under conditions of biological sulphate reduction

Sulphidogenous microorganism communities were isolated from soil polluted by crude oil. The study was focused on determining the influence of 1) copper (II) concentration on the activity of selected microorganism communities and 2) the applied electron donor on the course and evolution of mineral-forming processes under conditions favouring growth of sulphate-reducing bacteria (SRB). The influence of copper concentration on the activity of selected microorganism communities and the type of mineral phases formed was determined during experiments in which copper (II) chloride at concentrations of 0.1, 0.2, 0.5 and 0.7 g/L was added to SRB cultures. The experiments were performed in two variants: with ethanol (4 g/L) or lactate (4 g/L) as the sole carbon source. In order to determine the taxonomic composition of the selected microorganism communities, the 16S rRNA method was used. Results of this analysis confirmed the presence of Desulfovibrio, Desulfohalobium, Desulfotalea, Thermotoga, Solibacter, Gramella, Anaeromyxobacter and Myxococcus sp. in the stationary cultures. The post-culture sediments contained covelline (CuS) and digenite (Cu9S5). Based on the results, it can be stated that the type of carbon source applied during incubation plays a crucial role in determining the mineral composition of the post-culture sediments. Thus, regardless of the amount of copper ion introduced to a culture with lactate as the sole carbon source, no copper sulphide was observed in the post-culture sediments. Cultures with ethanol as the sole carbon source, on the other hand, yielded covelline or digenite in all post-culture sediments

“All quiet at the bottom”, that is about the need to undertake multidisciplinary research of interactions in the fracturing fluids – gas-containing shale – groundwater system

Po raz pierwszy w Polsce, przeprowadzono multidyscyplinarne badania cieczy szczelinujących i cieczy po szczelinowaniu hydraulicznym (cieczy zwrotnej) w celu oceny ich potencjału mikrobiologicznego oraz opisu interakcji ze skałami łupkowymi i wodami podziemnymi. W cieczy zwrotnej stwierdzono liczne mikroorganizmy tlenowe i beztlenowe mogące modyfikować jej skład i właściwości fizyczno-chemiczne. Wyniki wskazują, że podczas zabiegu szczelinowania ciecz szczelinująca szybko zmienia swój skład (wzrasta stężenie większości składników), co inicjuje różnorodne procesy geochemiczne, biogeochemiczne, minerałotwórcze. Zmieniający się skład cieczy wpływa na trwałość istniejących i tworzenie się nowych minerałów. Przedstawione wyniki badań mają między innymi znaczenie dla oceny żywotności otworów eksploatacyjnych i efektywności wydobycia gazu oraz oceny bezpieczeństwa wyżejległych poziomów wodonośnych.The first in Poland, multidisciplinary research on fracturing and flow-back fluids were carried out to the purpose of characterization of their microbiological potential and understanding interactions with shale rock and groundwater. Flow-back fluids contain abundant aerobic and anaerobic microorganisms, which can modify their properties and chemical composition. Results show that during and after hydraulic fracturing fluids quickly change their chemistry (increase of most solutes), what initiate various geochemical, biogeochemical, and mineralogical processes. The changing chemistry of fracturing fluids affects the stability of present minerals and the formation of new ones. Presented research are also important in terms of the gas borehole lifespan and the recovery of gas resource, and the safety assessment for overlying aquifers

Microbiological and molecular analysis for understanding phenomena in an abandoned water well

W porzuconym otworze studziennym funkcjonującym w krajowej sieci monitoringu wód podziemnych przeprowadzono badania geomikrobiologiczne. Stwierdzono powszechne, rozległe zarośnięcie ścian otworu oraz wypełnienie światła otworu biomatą mikrobiologiczną na głębokości około 100 m. Przy pomocy analizy mikrobiologicznej wykryto znaczną ilość mikroorganizmów w wodzie, natomiast analiza molekularna próbek biomaty wykazała obecność współistniejących bakterii redukujących siarczany oraz bakterii cyklu żelazowo-siarkowego. Obecność tak rozwiniętych zespołów mikrobiologicznych może być oznaką dopływu wraz z wodą materii organicznej oraz jonów SO42- i Fe2+ niezbędnych do wzrostu mikroorganizmów stwierdzonych w biomacie, co z kolei może znacząco wpływać na chemizm wody.Geomicrobiological studies were performed in the abandoned water well which still function in the national groundwater monitoring network. Extensive biofouling of cases and screens, as well as microbial mat, which completely fill-up the well at the depth of about 100 m, have been found. The microbiological analysis documented abundant microorganisms in water, while the molecular analysis of microbial mat revealed the coexistence of sulphate reducing and iron-sulphur cycle bacteria. The presence of such developed microbiological communities might indicate organic matter and SO42- and Fe2+ ions supply necessary for the growth of microorganisms found in the mat, which in turn would significantly affect the water chemistry

Geomicrobiology of Acid Mine Drainage in the weathering zone of pyrite-bearing schists in the Rudawy Janowickie Mountains (Poland)

This paper presents the geomicrobiological analysis of acid water reservoirs and Acid Mine Drainage (AMD) developed in the weathering zone of pyrite-bearing schists near the closed-down pyrite mine in Wieściszowice (south-western Poland). The analysis was focused on two reservoirs characterized by different physical and chemical properties (pH, redox potential, content of sulphates and heavy metals). The study is the first thorough report on the geomicrobiological relationships taking place in the AMD setting in Wieściszowice and enables a description of the microbiological processes that significantly influence biogeochemical cycles of sulfur and iron in the analyzed water reservoirs. The reservoir water also harbors numerous big, organized microbial structures in the form of streamers. Samples of these structures were studied in detail using optical and electron microscopy, as well as microbiological cultivation and molecular methods. According to the obtained results, the slime streamers from the Wieściszowice mine are characterized by the co-occurrence of typical chemolithoautotrophic microorganisms oxidizing sulphur and iron together with sulphate reducing bacteria. The presence of these structures probably depends on the occurrence of iron (II) in the surrounding environment