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Xie YX, Cheng WC, Xue ZF, Rahman MM, Wang L. Deterioration phenomenon of Pb-contaminated aqueous solution remediation and enhancement mechanism of nano-hydroxyapatite-assisted biomineralization. JOURNAL OF HAZARDOUS MATERIALS 2024; 470:134210. [PMID: 38581876 DOI: 10.1016/j.jhazmat.2024.134210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 04/01/2024] [Accepted: 04/02/2024] [Indexed: 04/08/2024]
Abstract
Modern metallurgical and smelting activities discharge the lead-containing wastewater, causing serious threats to human health. Bacteria and urease applied to microbial-induced carbonate precipitation (MICP) and enzyme-induced carbonate precipitation (EICP) are denatured under high Pb2+ concentration. The nano-hydroxyapatite (nHAP)-assisted biomineralization technology was applied in this study for Pb immobilization. Results showed that the extracellular polymers and cell membranes failed to secure the urease activity when subjected to 60 mM Pb2+. The immobilization efficiency dropped to below 50% under MICP, whereas it due to a lack of extracellular polymers and cell membranes dropped to below 30% under EICP. nHAP prevented the attachment of Pb2+ either through competing with bacteria and urease or promoting Ca2+/Pb2+ ion exchange. Furthermore, CO32- from ureolysis replaced the hydroxyl (-OH) in hydroxylpyromorphite to encourage the formation of carbonate-bearing hydroxylpyromorphite of higher stability (Pb10(PO4)6CO3). Moreover, nHAP application overcame an inability to provide nucleation sites by urease. As a result, the immobilization efficiency, when subjected to 60 mM Pb2+, elevated to above 80% under MICP-nHAP and to some 70% under EICP-nHAP. The findings highlight the potential of applying the nHAP-assisted biomineralization technology to Pb-containing water bodies remediation.
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Affiliation(s)
- Yi-Xin Xie
- School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an 710055, China
| | - Wen-Chieh Cheng
- School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an 710055, China.
| | - Zhong-Fei Xue
- School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an 710055, China
| | - Md Mizanur Rahman
- Geotechnical Engineering, UniSA STEM, ScaRCE, University of South Australia, SA 5000, Australia
| | - Lin Wang
- School of Civil Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Geotechnical and Underground Space Engineering (XAUAT), Xi'an 710055, China
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Sun B, Zhu R, Shi Y, Zhang W, Zhou Z, Ma D, Wang R, Dai H, Che C. Effects of coal-fired power plants on soil microbial diversity and community structures. J Environ Sci (China) 2024; 137:206-223. [PMID: 37980009 DOI: 10.1016/j.jes.2023.02.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 02/03/2023] [Accepted: 02/07/2023] [Indexed: 11/20/2023]
Abstract
Long-term deposition of atmospheric pollutants emitted from coal combustion and their effects on the eco-environment have been extensively studied around coal-fired power plants. However, the effects of coal-fired power plants on soil microbial communities have received little attention through atmospheric pollutant deposition and coal-stacking. Here, we collected the samples of power plant soils (PS), coal-stacking soils (CSS) and agricultural soils (AS) around three coal-fired power plants and background control soils (BG) in Huainan, a typical mineral resource-based city in East China, and investigated the microbial diversity and community structures through a high-throughput sequencing technique. Coal-stacking significantly increased (p < 0.05) the contents of total carbon, total nitrogen, total sulfur and Mo in the soils, whereas the deposition of atmospheric pollutants enhanced the levels of V, Cu, Zn and Pb. Proteobacteria, Actinobacteria, Thaumarchaeota, Thermoplasmata, Ascomycota and Basidiomycota were the dominant taxa in all soils. The bacterial community showed significant differences (p < 0.05) among PS, CSS, AS and BG, whereas archaeal and fungal communities showed significant differences (p < 0.01) according to soil samples around three coal-fired power plants. The predominant environmental variables affecting soil bacterial, archaeal and fungal communities were Mo-TN-TS, Cu-V-Mo, and organic matter (OM)-Mo, respectively. Certain soil microbial genera were closely related to multiple key factors associated with stacking coal and heavy metal deposition from power plants. This study provided useful insight into better understanding of the relationships between soil microbial communities and long-term disturbances from coal-fired power plants.
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Affiliation(s)
- Bowen Sun
- Institute of Polar Environment & Anhui Key Laboratory of Polar Environment and Global Change, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Renbin Zhu
- Institute of Polar Environment & Anhui Key Laboratory of Polar Environment and Global Change, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China.
| | - Yu Shi
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng 450046, China
| | - Wanying Zhang
- Institute of Polar Environment & Anhui Key Laboratory of Polar Environment and Global Change, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Zeming Zhou
- Institute of Polar Environment & Anhui Key Laboratory of Polar Environment and Global Change, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Dawei Ma
- State Grid Anhui Electric Power Research Institute, Hefei 230601, China
| | - Runfang Wang
- State Grid Anhui Electric Power Research Institute, Hefei 230601, China
| | - Haitao Dai
- Institute of Polar Environment & Anhui Key Laboratory of Polar Environment and Global Change, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Chenshuai Che
- Institute of Polar Environment & Anhui Key Laboratory of Polar Environment and Global Change, School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
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Harpke M, Kothe E. Biofilm formation in Gram-positives as an answer to combined salt and metal stress. J Basic Microbiol 2023. [PMID: 37189214 DOI: 10.1002/jobm.202300149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 04/17/2023] [Accepted: 04/24/2023] [Indexed: 05/17/2023]
Abstract
Biofilm formation can lead to tolerance against stressors like antibiotics, toxic metals, salts, and other environmental contaminants. Halo- and metal-tolerant bacilli and actinomycete strains isolated from a former uranium mining and milling site in Germany were shown to form biofilm in response to salt and metal treatment; specifically, Cs and Sr exposition led to biofilm formation. Since the strains were obtained from soil samples, a more structured environment was tested using expanded clay to provide porous structures resembling the natural environment. There, accumulation of Cs could be shown for Bacillus sp. SB53B, and high Sr accumulation ranging from 75% to 90% was seen with all isolates tested. We could, therefore, show that biofilms in a structured environment like soil will contribute to the water purification obtained by the passage of water through the critical zone of soil, providing an ecosystem benefit that can hardly be overestimated.
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Affiliation(s)
- Marie Harpke
- Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Erika Kothe
- Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
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Sánchez-Porro C. Special Issue “Halophilic Microorganisms”. Microorganisms 2023; 11:microorganisms11030690. [PMID: 36985263 PMCID: PMC10052812 DOI: 10.3390/microorganisms11030690] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 03/03/2023] [Indexed: 03/11/2023] Open
Abstract
Hypersaline environments are mainly represented by aquatic systems, such as solar salt ponds or natural salt lakes, as well as by the sediments of these hypersaline aquatic ecosystems and soils with high salt content [...]
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Affiliation(s)
- Cristina Sánchez-Porro
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla, 41012 Sevilla, Spain
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Xiao X, Zhang YL, Zhou ZA, Wu F, Wang HF, Zong X. Response of sediment microbial communities to different levels of PAC contamination and exposure time. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 861:160683. [PMID: 36481151 DOI: 10.1016/j.scitotenv.2022.160683] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/18/2022] [Accepted: 11/30/2022] [Indexed: 06/17/2023]
Abstract
Coagulants such as polyaluminium chloride (PAC) are widely used for removing phosphorus from eutrophic water, but its application for water treatment can potentially harm the environment. In this study, a four-timepoint exposure experiment was performed at week 1, 3, 7 and 10 to investigate how microbial communities in lake sediments respond to different concentrations of PAC (RS (raw lake water with nothing added), Low, Medium and High). The results showed that, while PAC can efficiently decrease the amount of C, N and P in lake water, the presence of residual aluminum and aluminum precipitates can greatly affect the microbial communities in lake sediments. In particular, different concentrations of PAC and exposure time affected the microbial diversity and structure of lake sediments, with changes being especially obvious at high concentration of PAC after 10 weeks of exposure. Moreover, the use of PAC significantly increased the relative abundances of Gammaproteobacteria and Competibacter, while reducing those of Thermodesulfovibrionia, Vicinamibacterales, and BSV26 in time- and concentration-dependent manners. Network analysis further showed strong correlations between differential bacterial species of PAC in high concentration at 10 weeks, which further suggested that PAC treatment changed the complex structure of microbiota in lake sediment. Finally, correlation analysis indicated a close connection between water parameters and differential species induced by PAC treatment. Overall, PAC contamination changed the microbial communities at different taxonomy levels and influenced the functional pathways to potentiate the P removal, and the results offered interesting insights into the use of PAC in water treatment and its impact on biogeochemical cycling. These results indicated that more attention need to be paid to the potential impact of chemical phosphorus removing reagents on the environment, including eutrophic water.
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Affiliation(s)
- Xiao Xiao
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou 311300, China
| | - Ya-Li Zhang
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou 311300, China; Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Zi-An Zhou
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Fan Wu
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Hou-Feng Wang
- Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
| | - Xin Zong
- Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province, College of Animal Science and Technology, College of Veterinary Medicine, Zhejiang A&F University, Hangzhou 311300, China; Key Laboratory of Animal Nutrition and Feed Science in Eastern China, Ministry of Agriculture, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; Key laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China.
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Boussageon R, van Tuinen D, Lapadatescu C, Trépanier M, Vermersch E, Wipf D, Courty PE. Effects of field inoculation of potato tubers with the arbuscular mycorrhizal fungus Rhizophagus irregularis DAOM 197,198 are cultivar dependent. Symbiosis 2023. [DOI: 10.1007/s13199-023-00908-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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Fu B, Fang C, Xia J, Pan S, Zhou L, Peng Y, Yan Y, Yang Y, He Y, Chen S, Yang H, Wang J. Urbanization alters soil bacterial communities in southern China coastal cities. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2023; 250:114492. [PMID: 36603487 DOI: 10.1016/j.ecoenv.2022.114492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 12/18/2022] [Accepted: 12/29/2022] [Indexed: 06/17/2023]
Abstract
Urbanization carries essential influences to ecosystem of soil bacteria in coastal cities. Comprehending the patterns and drivers of bacterial diversity are essential to understanding how soil ecosystems respond to environmental change. This study aimed to explore how soil bacterial community (SBC) response to distinct urbanization of coastal cities on composition, assembly process and potential function in Guangdong province, south China. 72 samples from 24 sample sites within 3 cities were included in the study. Soil chemical properties were analyzed, and the bacterial community were investigated by high-throughout sequencing. Proteobacteria and Acidobacteria were the main phyla. Assembly processes remained in stochastic processes and co-occurrence network of SBC kept stable, while urbanization altered SBC by influencing the dominant phyla. The indicators of communities in coastal city soils were the genera gamma_proteobacterium and beta_proteobacterium. Urbanized extent was the non-negligible factor which affected soil bacterial community, despite the total carbon was still the most vital. The impact of urbanization on bacterial communities might follow a non-linear pattern. Faprotax function prediction showed different urbanized coastal city soils share similar metabolic potential. Our study improved our understanding of the response of soil bacterial communities to urbanization in subtropical coastal cities and offered a useful strategy to monitor the ecology risk toward the soil under urbanization.
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Affiliation(s)
- Bing Fu
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China; Zhongshan Innovation Center of South China Agricultural University, Zhongshan 528400, China
| | - Chang Fang
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China; Zhongshan Innovation Center of South China Agricultural University, Zhongshan 528400, China
| | - Jun Xia
- Institute of Veterinary Medicine, Xinjiang Academy of Animal Sciences (Research Center for Veterinary Clinical Medicine, Xinjiang Academy of Animal Sciences), Key Laboratory of Herbivore Disease Prevention and Control, Ministry of Agriculture and Rural Affairs, Urumqi 830000, China
| | - Sentao Pan
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China; Zhongshan Innovation Center of South China Agricultural University, Zhongshan 528400, China
| | - Lei Zhou
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Yisheng Peng
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510006, China
| | - Yumeng Yan
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Yan Yang
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China
| | - Yinglin He
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China; Zhongshan Innovation Center of South China Agricultural University, Zhongshan 528400, China
| | - Shijun Chen
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China; Zhongshan Innovation Center of South China Agricultural University, Zhongshan 528400, China.
| | - Huirong Yang
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China; Zhongshan Innovation Center of South China Agricultural University, Zhongshan 528400, China.
| | - Jun Wang
- College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China
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Harpke M, Pietschmann S, Ueberschaar N, Krüger T, Kniemeyer O, Brakhage AA, Nietzsche S, Kothe E. Salt and Metal Tolerance Involves Formation of Guttation Droplets in Species of the Aspergillus versicolor Complex. Genes (Basel) 2022; 13:genes13091631. [PMID: 36140799 PMCID: PMC9498632 DOI: 10.3390/genes13091631] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 09/02/2022] [Accepted: 09/06/2022] [Indexed: 11/16/2022] Open
Abstract
Three strains of the Aspergillus versicolor complex were isolated from a salty marsh at a former uranium mining site in Thuringia, Germany. The strains from a metal-rich environment were not only highly salt tolerant (up to 20% NaCl), but at the same time could sustain elevated Cs and Sr (both up to 100 mM) concentrations as well as other (heavy) metals present in the environment. During growth experiments when screening for differential cell morphology, the occurrence of guttation droplets was observed, specifically when elevated Sr concentrations of 25 mM were present in the media. To analyze the potential of metal tolerance being promoted by these excretions, proteomics and metabolomics of guttation droplets were performed. Indeed, proteins involved in up-regulated metabolic activities as well as in stress responses were identified. The metabolome verified the presence of amino sugars, glucose homeostasis-regulating substances, abscisic acid and bioactive alkaloids, flavones and quinones.
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Affiliation(s)
- Marie Harpke
- Institute of Microbiology, Friedrich Schiller University Jena, Neugasse 25, 07743 Jena, Germany
| | - Sebastian Pietschmann
- Institute of Microbiology, Friedrich Schiller University Jena, Neugasse 25, 07743 Jena, Germany
| | - Nico Ueberschaar
- Mass Spectrometry Platform, Friedrich Schiller University Jena, Humboldtstr. 8, 07743 Jena, Germany
| | - Thomas Krüger
- Leibniz Institute for Natural Product Research and Infection Biology, Department of Molecular and Applied Microbiology, Adolf-Reichwein-St. 23, 07745 Jena, Germany
| | - Olaf Kniemeyer
- Leibniz Institute for Natural Product Research and Infection Biology, Department of Molecular and Applied Microbiology, Adolf-Reichwein-St. 23, 07745 Jena, Germany
| | - Axel A. Brakhage
- Institute of Microbiology, Friedrich Schiller University Jena, Neugasse 25, 07743 Jena, Germany
- Leibniz Institute for Natural Product Research and Infection Biology, Department of Molecular and Applied Microbiology, Adolf-Reichwein-St. 23, 07745 Jena, Germany
| | - Sandor Nietzsche
- Elektronenmikroskopisches Zentrum, Universitätsklinikum Jena, Ziegelmühlenweg 1, 07743 Jena, Germany
| | - Erika Kothe
- Institute of Microbiology, Friedrich Schiller University Jena, Neugasse 25, 07743 Jena, Germany
- Correspondence:
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Extremophile Metal Resistance: Plasmid-Encoded Functions in Streptomyces mirabilis. Appl Environ Microbiol 2022; 88:e0008522. [PMID: 35604229 PMCID: PMC9195940 DOI: 10.1128/aem.00085-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The extreme metal tolerance of up to 130 mM NiSO4 in Streptomyces mirabilis P16B-1 was investigated. Genome sequencing revealed the presence of a large linear plasmid, pI. To identify plasmid-encoded determinants of metal resistance, a newly established transformation system was used to characterize the predicted plasmid-encoded loci nreB, hoxN, and copYZ. Reintroduction into the plasmid-cured S. mirabilis ΔpI confirmed that the predicted metal transporter gene nreB constitutes a nickel resistance factor, which was further supported by its heterologous expression in Escherichia coli. In contrast, the predicted nickel exporter gene hoxN decreased nickel tolerance, while copper tolerance was enhanced. The predicted copper-dependent transcriptional regulator gene copY did not induce tolerance toward either metal. Since genes for transfer were identified on the plasmid, its conjugational transfer to the metal-sensitive Streptomyces lividans TK24 was checked. This resulted in acquired tolerance toward 30 mM nickel and additionally increased the tolerance toward copper and cobalt, while oxidative stress tolerance remained unchanged. Intracellular nickel concentrations decreased in the transconjugant strain. The high extracellular nickel concentrations allowed for biomineralization. Plasmid transfer could also be confirmed into the co-occurring actinomycete Kribbella spp. in soil microcosms. IMPORTANCE Living in extremely metal-rich environments requires specific adaptations, and often, specific metal tolerance genes are encoded on a transferable plasmid. Here, Streptomyces mirabilis P16B-1, isolated from a former mining area and able to grow with up to 130 mM NiSO4, was investigated. The bacterial chromosome, as well as a giant plasmid, was sequenced. The plasmid-borne gene nreB was confirmed to confer metal resistance. A newly established transformation system allowed us to construct a plasmid-cured S. mirabilis as well as an nreB-rescued strain in addition to confirming nreB encoding nickel resistance if heterologously expressed in E. coli. The potential of intra- and interspecific plasmid transfer, together with the presence of metal resistance factors on that plasmid, underlines the importance of plasmids for transfer of resistance factors within a bacterial soil community.
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Biomineralization of Nickel Struvite Linked to Metal Resistance in Streptomyces mirabilis. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27103061. [PMID: 35630535 PMCID: PMC9145468 DOI: 10.3390/molecules27103061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 05/03/2022] [Accepted: 05/05/2022] [Indexed: 11/22/2022]
Abstract
Biomineral formation is a common trait and prominent for soil Actinobacteria, including the genus Streptomyces. We investigated the formation of nickel-containing biominerals in the presence of a heavy-metal-resistant Streptomyces mirabilis P16B-1. Biomineralization was found to occur both in solid and liquid media. Minerals were identified with Raman spectroscopy and TEM-EDX to be either Mg-containing struvite produced in media containing no nickel, or Ni-struvite where Ni replaces the Mg when nickel was present in sufficient concentrations in the media. The precipitation of Ni-struvite reduced the concentration of nickel available in the medium. Therefore, Ni-struvite precipitation is an efficient mechanism for tolerance to nickel. We discuss the contribution of a plasmid-encoded nickel efflux transporter in aiding biomineralization. In the elevated local concentrations of Ni surrounding the cells carrying this plasmid, more biominerals occurred supporting this point of view. The biominerals formed have been quantified, showing that the conditions of growth do influence mineralization. This control is also visible in differences observed to biosynthetically synthesized Ni-struvites, including the use of sterile-filtered culture supernatant. The use of the wildtype S. mirabilis P16B-1 and its plasmid-free derivative, as well as a metal-sensitive recipient, S. lividans, and the same transformed with the plasmid, allowed us to access genetic factors involved in this partial control of biomineral formation.
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