Mercury Reduction by Bacteria Isolated from Informal Mining Zones

The aim of this research was the selection of bacterial strains resistant to mercury, as well as to demonstrate their capacity to reduce mercury in solution when they are inoculated in pure and mixed cultures. Samples of soil from informal mining gold sites in Peru were collected and fifteen mercury resistant bacteria were isolated. Strains RM6, RM7, RM9, RM11, RM12 and RM13 were selected for their capacity to reduce mercury in solution. The six bacterial strains belong to the genus Pseudomonas. Inoculated in pure cultures, these strains reduce mercury in solution although in different percentages: RM9, RM11 an RM12 reduce 93% to 97% of the mercury, while strains RM6, RM7 y RM13 reduce 80% to 85%. The consortium of all six bacterial strains showed a mercury reduction of 84%. Approximately 91% of mercury in solution was reduced in 1 hour and this reaction was not associated to bacterial growth. Using specific primers, the merA gene was amplified from genomic DNA of the bacterial strains, which would suggest the activity of the mer operon as a mechanism of mercury resistance. Due to their ability to reduce mercury in solution, it is advisable to carry out more research on the selected strains since they could be useful in future bioremediation processes.

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Isolation and characterization of mercury-resistant bacteria from wastewater sources in Egypt

Canadian Journal of Microbiology ◽

10.1139/cjm-2018-0379 ◽

2019 ◽

Vol 65 (4) ◽

pp. 308-321 ◽

Cited By ~ 3

Author(s):

Martha M. Naguib ◽

Ahmed S. Khairalla ◽

Ahmed O. El-Gendy ◽

Walid F. Elkhatib

Keyword(s):

Elemental Mercury ◽

Resistant Bacteria ◽

Bacterial Strains ◽

Gram Negative ◽

Isolation And Characterization ◽

High Mercury ◽

Mercury Tolerance ◽

High Degree ◽

Mera Gene ◽

Mercury Resistant Bacteria

An important mechanism for microbial resistance to mercury is its reduction into elemental mercury (facilitated by the merA gene). Thirty-eight microbial isolates from a variety of wastewater sources in Egypt were collected. Approximately 14 of the 38 isolates exhibited not only a high degree of tolerance to mercury (up to 160 ppm) but also a high degree of resistance to other tested heavy metals (Cu, Co, Ni, and Zn). From these 14, the 10 most resistant isolates were selected for further study and were found to include 9 Gram-negative and 1 Gram-positive bacterial strains. Multi-antibiotic-resistance profiles were detected for 6 out of the 10 selected isolates. All the tested Gram-negative isolates (n = 9) harbored a plasmid-encoded merA gene. The mercury removal effectiveness for the 10 selected isolates ranged between 50% and 99.9%, among which Stenotrophomonas maltophilia ADW10 recorded the highest rate (99.9%; at an initial mercury concentration of 20 ppm). To the best of our knowledge, this is the first study to (i) demonstrate the presence of a multimetal-resistant S. maltophilia bacterium with a high mercury tolerance capacity that would make it a suitable candidate for future bioremediation efforts in heavy-metal-polluted areas in Egypt and (ii) report Pseudomonas otitidis as one of the mercury-resistant bacteria.

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Potential risks of antibiotic resistant bacteria and genes in bioremediation of petroleum hydrocarbon contaminated soils

Environmental Science Processes & Impacts ◽

10.1039/c9em00606k ◽

2020 ◽

Vol 22 (5) ◽

pp. 1110-1124 ◽

Cited By ~ 2

Author(s):

Colin J. Cunningham ◽

Maria S. Kuyukina ◽

Irena B. Ivshina ◽

Alexandr I. Konev ◽

Tatyana A. Peshkur ◽

...

Keyword(s):

Antibiotic Resistance ◽

Contaminated Soil ◽

Contaminated Soils ◽

Petroleum Hydrocarbon ◽

Resistant Bacteria ◽

Careful Selection ◽

Bacterial Strains ◽

Antibiotic Resistant ◽

Potential Risks ◽

Selection Of

The problems associated with potential risks of antibiotic resistance spreading during bioremediation of oil-contaminated soil are discussed. Careful selection of bacterial strains and pretreatment of organic wastes used as fertilizers are suggested.

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EPS production and bioremoval of heavy metals by mixed and pure bacterial cultures isolated from Ankara Stream

Water Science & Technology ◽

10.2166/wst.2015.365 ◽

2015 ◽

Vol 72 (9) ◽

pp. 1488-1494 ◽

Cited By ~ 6

Author(s):

Nur Koçberber Kiliç ◽

Güliz Kürkçü ◽

Durna Kumruoğlu ◽

Gönül Dönmez

Keyword(s):

Heavy Metal ◽

Metal Removal ◽

Heavy Metal Removal ◽

Mixed Cultures ◽

Resistant Bacteria ◽

Bacterial Strains ◽

Bacterial Cultures ◽

Removal Capacity ◽

Pure Cultures ◽

Pure Bacterial Cultures

This study is focused on isolation of Ni(II), Cu(II) and Cr(VI) resistant bacteria to assess their exopolysaccharide (EPS) production and related bioremoval capacities. Mixed cultures had higher heavy metal removal capacity in media with molasses (MAS) than the control cultures lacking this carbon (AS) containing 50 mg/l of heavy metal. The yields were 32%, 75.7%, and 51.1% in MAS, while the corresponding values were 29%, 55.1%, and 34.5% in AS, respectively. Purification of the strains 1, 5 and 6 present in the mixed cultures decreased the bioremoval capacities of the mixed culture samples, although these strains produced higher EPS amounts in MAS agar. Strain 5 had the highest Cu(II) (69.1%) and Cr(VI) (43.1%) removal rates at 25 mg/l initial concentration of each pollutant with EPS amounts of 0.74 g/l and 1.05 g/l, respectively. This strain was identified as Stenotrophomonas maltophilia. The presented data show that especially mixed and also pure cultures of bacterial strains isolated from Ankara Stream could be assessed as potential bioremoval agents in the treatment of Cu(II) or Cr(VI) containing wastewaters.

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Pengaruh pH dan Suhu terhadap Aktivitas Pereduksi Merkuri Bakteri Resisten Merkuri Tinggi Bacillus cereus yang Diisolasi dari Urin Pasien dengan Amalgam Gigi

e-GIGI ◽

10.35790/eg.8.1.2020.28291 ◽

2020 ◽

Vol 8 (1) ◽

Author(s):

Billy J. Kepel ◽

Widdhi Bodhi ◽

. Fatimawali

Keyword(s):

Bacillus Cereus ◽

Incubation Temperature ◽

Mercury Resistance ◽

Resistant Bacteria ◽

Growth Media ◽

Mercury Compounds ◽

Reducing Activity ◽

Mercury Detoxification ◽

Incubation Temperatures ◽

Mercury Resistant Bacteria

Abstract: Mercury is a very toxic compound to humans, therefore, a method to overcome its presence in the environment is required. Detoxification of mercury can be done by using mercury resistant bacteria. Mercury-resistant bacteria Bacillus cereus isolate FUA have been obtained from the urine of patients with dental mercury amalgam. This study was aimed to determine the mercury detoxification activity of Bacillus cereus isolate FUA at varying pH medium and incubation temperature. The study was carried out by growing Bacillus cereus isolate FUA on oblique media, then were planted in the growth media of LB broth containing mercury compounds of 10 ppm HgCl2 with varying pHs of 5, 7, and 9 and incubation temperatures of 15, 25 and 35oC. The amount of bacterial growth was analyzed by using spectrophotometer and mercury levels were analyzed by using CV-AAS method. The results showed that the growth and mercury reducing activity of Bacillus cereus isolate FUA were optimum at pH 7 and incubation temperature of 35oC. In conclusion, the growth of Bacillus cereus isolate FUA and its mercury reducing activity were optimum at pH 7 and temperature of 35oC. It is expected that the results of this study can be the basis for further research on the process of mercury detoxificationKeywords: Bacillus cereus, urine, mercury resistance, pH, temperature Abstrak: Merkuri adalah senyawa yang sangat beracun bagi manusia sehingga diperlukan metode untuk mengatasi keberadaannya di lingkungan. Detoksifikasi merkuri dapat dilakukan dengan menggunakan bakteri resisten merkuri. Bakteri yang resisten merkuri Bacillus cereus isolat FUA telah diperoleh dari urin pasien dengan amalgam gigi. Penelitian ini bertujuan untuk mengetahui aktivitas detoksifikasi merkuri Bacillus cereus isolat FUA pada berbagai variasi pH medium dan suhu inkubasi. Bakteri Bacillus cereus isolat FUA ditumbuhkan pada media miring, kemudian ditanam pada media pertumbuhan bakteri LB broth yang mengandung senyawa merkuri 10 ppm HgCl2 dengan berbagai pH 5, 7 dan 9 dan suhu inkubasi 15, 25 dan 35oC. Jumlah pertumbuhan bakteri dianalisis menggunakan spektrofotometer dan kadar merkuri dianalisis menggunakan metode CV-AAS. Hasil penelitian menunjukkan bahwa aktivitas pertumbuhan dan aktivitas pereduksi merkuri Bacillus cereus isolat FUA optimum pada lingkungan pertumbuhan dengan pH 7 dan suhu inkubasi 35oC. Simpulan penelitian ini ialah aktivitas pertumbuhan dan pereduksi merkuri Bacillus cereus isolat FUA yang optimum pada pH 7 dan suhu 35oC. Diharapkan hasil penelitian ini dapat menjadi dasar untuk penelitian lebih lanjut tentang proses detoksifikasi merkuri.Kata kunci: Bacillus cereus, urin, resistensi merkuri, pH, suhu

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Cultivation of Hard-To-Culture Subsurface Mercury-Resistant Bacteria and Discovery of New merA Gene Sequences

Applied and Environmental Microbiology ◽

10.1128/aem.00049-08 ◽

2008 ◽

Vol 74 (12) ◽

pp. 3795-3803 ◽

Cited By ~ 33

Author(s):

L. D. Rasmussen ◽

C. Zawadsky ◽

S. J. Binnerup ◽

G. Øregaard ◽

S. J. Sørensen ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Molecular Techniques ◽

Resistant Bacteria ◽

Rrna Gene ◽

Gene Sequences ◽

16S Rrna Gene Sequences ◽

Direct Plating ◽

Mercury Reduction ◽

Mercury Resistant Bacteria

ABSTRACT Mercury-resistant bacteria may be important players in mercury biogeochemistry. To assess the potential for mercury reduction by two subsurface microbial communities, resistant subpopulations and their merA genes were characterized by a combined molecular and cultivation-dependent approach. The cultivation method simulated natural conditions by using polycarbonate membranes as a growth support and a nonsterile soil slurry as a culture medium. Resistant bacteria were pregrown to microcolony-forming units (mCFU) before being plated on standard medium. Compared to direct plating, culturability was increased up to 2,800 times and numbers of mCFU were similar to the total number of mercury-resistant bacteria in the soils. Denaturing gradient gel electrophoresis analysis of DNA extracted from membranes suggested stimulation of growth of hard-to-culture bacteria during the preincubation. A total of 25 different 16S rRNA gene sequences were observed, including Alpha-, Beta-, and Gammaproteobacteria; Actinobacteria; Firmicutes; and Bacteroidetes. The diversity of isolates obtained by direct plating included eight different 16S rRNA gene sequences (Alpha- and Betaproteobacteria and Actinobacteria). Partial sequencing of merA of selected isolates led to the discovery of new merA sequences. With phylum-specific merA primers, PCR products were obtained for Alpha- and Betaproteobacteria and Actinobacteria but not for Bacteroidetes and Firmicutes. The similarity to known sequences ranged between 89 and 95%. One of the sequences did not result in a match in the BLAST search. The results illustrate the power of integrating advanced cultivation methodology with molecular techniques for the characterization of the diversity of mercury-resistant populations and assessing the potential for mercury reduction in contaminated environments.

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ISOLASI DAN IDENTIFIKASI BAKTERI RESISTEN MERKURI DARI MUARA SUNGAI SARIO YANG DAPAT DIGUNAKAN UNTUK DETOKSIFIKASI LIMBAH MERKURI

JURNAL ILMIAH SAINS ◽

10.35799/jis.11.2.2011.220 ◽

2011 ◽

Vol 15 (1) ◽

pp. 282 ◽

Cited By ~ 1

Author(s):

Fatimawali Fatimawali ◽

Fatmawaty Badaruddin ◽

Irawan Yusuf

Keyword(s):

Klebsiella Pneumoniae ◽

Pure Culture ◽

Culture Media ◽

Inorganic Mercury ◽

River Estuary ◽

Nutrient Broth ◽

Resistant Bacteria ◽

Bacterial Strains ◽

Isolation And Identification ◽

Mercury Resistant Bacteria

ISOLASI DAN IDENTIFIKASI BAKTERI RESISTEN MERKURI DARI MUARA SUNGAI SARIO YANG DAPAT DIGUNAKAN UNTUK DETOKSIFIKASI LIMBAH MERKURI Fatimawali1), Fatmawaty Badaruddin2), Irawan Yusuf 2) 1)Dosen Fakultas Kedokteran Unsrat Manado dan Mahasiswa Program Doktor Fakultas Kedokteran Universitas Hasanuddin Makassar; 2)Dosen Fakultas Kedokteran Universitas Hasanuddin Makassar ABSTRAK Merkuri adalah logam berat yang bersifat sangat toksik, mempunyai afinitas terhadap gugus thiol protein. Keberadaan merkuri dilingkungan, karena secara alamiah maupun karena aktifitas antrofogenik. Di Kabupaten Bolaang Mongondow terdapat beberapa penambang emas rakyat yang menggunakan merkuri untuk mengekstrak emas dari batuan atau ore dan membuang limbah merkuri secara bebas ke lingkungan dan terbawa air hujan sampai kepada perairan. Sedimen perairan yang terkontaminasi merkuri dapat ditumbuhi bakteri resisten merkuri. Bakteri resisten merkuri anorhanik dapat digunakan untuk bioremediasi perairan, karena bakteri tersebut mampu mereduksi merkuri anorganik menjadi logam merkuri yang mudah menguap dan kurangtoksik. Dan merupakan sumber pencemaran merkuri. Bakteri resisten merkuri mempunyai operon mer yang biasanya terkandung dalam plasmid. Penelitian ini bertujuan untuk mengisolasi bakteri resisten merkuri anorganik, dan menganalisis kemampuannya dalam mereduksi HgCl2 dalam media nutrient broth. Bakteri resisten merkuri tinggi, dilakukan analisis Gen 16S rRNAnya untuk mengetahuis pesiesnya. Hasil penelitian menunjukkan bahwa isolat A1.1.1 merupakan bakteri spesies Klebsiella pneumoniae, mampu mereduksi HgCl2 75% dalam waktu 1 jam, 92% dalam waktu 12 jam dan 99,4% dalam waktu 24 jam Kata Kunci: bakteri, detoksifikasi, HgCl2, Klebsiella pneumoniae ISOLATION AND IDENTIFICATION OF MERCURY-RESISTANT BACTERIUM FROM SARIO RIVER ESTUARY THAT CAN BE USED TO DETOXIFY INORGANIK MERCURY WASTES ABSTRACT Mercury (Hg) is well known for its high toxicity and strong affinity toward the thiol group of proteins. When Hg released into the environment in substantial quantities through natural events and anthropogenic activities . In District of Bolaang Mongondow, many miners who are a source of mercury pollution of aquatic environments to which they use to extract gold from the rock or ore. Waters sediment contaminated with mercury, can be overgrown with microorganism such as bacteria that are resistant to mercury. Mercury-resistant bacteria can be used for bioremediation of waters due to the ability of these bacteria to reduce toxic inorganic mercury into mercury metal which is volatile and less toxic. Mercury-resistant bacteria has mer Operon which usually contained in the plasmid. The aim of this study was the selection of bacterial strains resistant to inorganic mercury, as well as to show their capacity to reduce mercury in pure culture media Nutrient Broth. Twelve isolate bacteria was selected for its capacity to reduce mercury HgCl2 in culture media nutrient broth. The one bacterial strains belong to the spesies Klebsiella pneumoniae. Inoculated in pure culture, these strain showed a mercury reduction of 75% in 1 hour, 92% in 12 hours, and 99,4% in 24 hours. Keywords : bacteria , detoxification, HgCl2 , Klebsiella pneumoniae

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Sorption Mechanism and Optimization Study for the Bioremediation of Pb(II) and Cd(II) Contamination by Two Novel Isolated Strains Q3 and Q5 of Bacillus sp.

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17114059 ◽

2020 ◽

Vol 17 (11) ◽

pp. 4059 ◽

Cited By ~ 1

Author(s):

Parviz Heidari ◽

Antonio Panico

Keyword(s):

Chemical Precipitation ◽

Bacillus Species ◽

Strongly Correlated ◽

Bacillus Sp ◽

Bacterial Strains ◽

Natural Ecosystems ◽

Optimization Study ◽

Initial Ph ◽

Pure Cultures ◽

Bioremediation Processes

The use of bacterial strains as agents in bioremediation processes could reduce the harmfulness of potential toxic elements (PTEs) from water and soil with low or even no impact on the natural ecosystems. In this study, two new metal resistant-bacterial strains (Q3 and Q5) of Bacillus sp. were isolated from a sulfurous spring and their potential (as pure cultures or mixed) to remove Pb(II) and Cd(II) from an aqueous matrix was evaluated and optimized using response surface methodology (RSM). The optimal conditions for Cd(II) removal from all tested strains combinations were observed at an initial pH 5, a temperature of 38 °C, and an initial Cd(II) concentration of 50 mg L−1, while the performance of bacterial strains on Pb(II) removal was strongly correlated to initial pH and temperature conditions. Moreover, the efficiency of bacterial strains in removing both PTEs, Pb(II) and Cd(II), from an aqueous matrix was considerably higher when they were used as a mixed culture rather than pure. According to field emission SEM (FESEM) and EDS analysis, the two bacterial strains showed different mechanisms in removing Cd(II): Bacillus sp. Q5 bio-accumulated Cd(II) in its periplasmic space, whereas Bacillus sp. Q3 bio-accumulated Cd(II) on its cell surface. On the other hand, Pb(II) is removed by chemical precipitation (lead sulfide) induced by both Bacillus sp. Q3 and Q5. This study discloses new aspects of Pb(II) and Cd(II) bioremediation mechanisms in Bacillus species that can be extremely useful for designing and operating novel PTEs bioremediation processes.

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Identification and characterization of anaerobic mercury-resistant bacteria isolated from mercury-polluted sediment

Water Science & Technology ◽

10.2166/wst.2000.0366 ◽

2000 ◽

Vol 42 (3-4) ◽

pp. 109-114 ◽

Cited By ~ 1

Author(s):

M. Narita ◽

C.C. Huang ◽

T. Koizumi ◽

T. Yamagata ◽

G. Endo

Keyword(s):

Nucleotide Sequence ◽

Inorganic Mercury ◽

Mercury Resistance ◽

Nucleotide Sequence Analysis ◽

Resistant Bacteria ◽

Chromosomal Dna ◽

Genetic Characteristics ◽

Polluted Sediment ◽

Minamata Bay ◽

Mercury Resistant Bacteria

To develop biotechnology for biological treatment of mercury-contaminated wastes or for bioremediation of mercury-polluted sites, mercury-resistant microorganisms have been isolated and characterized. However, understanding of the mercury resistance mechanism by anaerobic bacteria is lacking. In this study, we tried to isolate anaerobic mercury-resistant bacteria from mercury-polluted sediment in Minamata Bay, Japan. One strain of the bacterial isolates, designated Mersaru, was used for the identification and for the growth capability of mercurials. We also analyzed genetic characteristics of mercury resistance genes (merA and merB gene) from the strain Mersaru. The strain Mersaru, which was isolated from Minamata Bay sediment, was identified as Clostridium butyricum and showed resistance to both inorganic mercury and organomercurials. Furthermore, nucleotide sequence analysis showed that merA and merB genes of the strain Mersaru were identical to those of the B. cereus RC607 an aerobic mercury-resistant bacterium in the nucleotide sequence level. From the pulsed field gel electrophoresis analysis, it is suggest that the mer operon of the strain Mersaru is located on chromosomal DNA.

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STUDI POPULASI BAKTERI RESISTEN MERKURI DI DAERAH ALIRAN SUNGAI TONDANO, KELURAHAN KETANG BARU, MANADO

JURNAL ILMIAH SAINS ◽

10.35799/jis.11.1.2011.36 ◽

2011 ◽

Vol 11 (1) ◽

pp. 26

Author(s):

Aaltje E. Manampiring ◽

Billy J. Keppel

Keyword(s):

Escherichia Coli ◽

Mercury Resistance ◽

Resistant Bacteria ◽

Cross Sectional ◽

Watershed Area ◽

Descriptive Research ◽

Mercury Resistant Bacteria

Kadar merkuri yang tinggi di perairan umumnya dapat mempengaruhi keadaan biota termasuk bakteri yang resisten terhadap merkuri. Penelitian deskriptif yang menggunakan metode cross sectional bertujuan untuk menguji resistensi bakteri di aliran sungai Tondano, Kelurahan Ketang Baru, Manado terhadap merkuri. Escherichia coli dan Bacillus careus (isolat1,1 dan 2,2) hanya dapar tumbuh pada konsentrasi HgCl2 0,02%. Lactobacillus sp. dan Veillonella parvula (isolat 1,2 2,1 3,1 dan 3,2) tumbuh pada konsentrasi HgCl2 0,06%. Lactobacillus sp. (isolat 3,1) saja yang tumbuh pada konsentrasi HgCl2 0,1% dan tidak ada bakteri yang mampu tumbuh pada konsentrasi HgCl2 0,2%. STUDY ON POPULATION OF MERCURY-RESISTANT BACTERIAIN THE WATERSHED AREA OF TONDANO RIVER,KELURAHAN KETANG BARU, MANADOHigh concentration of mercury in the watershed area can affect biota condition, including mercury-resistant bacteria. This descriptive research with cross-sectional method aimed to evaluate the mercury-resistance of bacteria in watershed area of Tondano, Kelurahan Ketang Baru, Manado. Escherichia coli and Bacillus careus (isolates 1,1, dan 2,2) were able to grow in HgCl2 0,02%. Lactobacillus sp. and Veillonella parvula (isolates 1,2 2,1 3,1 and 3,2) grow in HgCl2 0,06%. Lactobacilus sp. (isolate 3,1) only grow in HgCl2 0,1% and none of bacteria could grow in HgCl2 0,2%.

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Efficacy of Photodynamic Inactivation against the Major Human Antibiotic-Resistant Uropathogens

Photonics ◽

10.3390/photonics8110495 ◽

2021 ◽

Vol 8 (11) ◽

pp. 495

Author(s):

Nadezhda Ignatova ◽

Tatiana Ivanova ◽

Artem Antonyan ◽

Ivan Budruev ◽

Olga Streltsova ◽

...

Keyword(s):

Renal Calculi ◽

Diffusion Method ◽

Resistant Bacteria ◽

Photodynamic Inactivation ◽

Bacterial Strains ◽

Antibiotic Resistant ◽

Drug Resistant Bacteria ◽

Complex Approach ◽

And Staphylococcus Aureus ◽

Selection Of

Photodynamic inactivation (PDI) is considered to be an effective method of prevention of postoperative complications of urolithiasis. The present study shows a complex approach to assess the efficacy of PDI of drug resistant bacteria associated with renal calculi. Bacterial strains associated with renal calculi were isolated and identified using standard methods of bacteriological analysis and tested for drug resistance to 10 antibiotics by the disco-diffusion method. Uropathogenic bacterial strains present in 78.7 ± 5.2% of the infected samples from the total number of analyzed calculi. The most frequent representatives belonged to the genera Staphylococcus, Escherichia, and Enterococcus. All tested strains showed high antibiotic resistance. Representatives of the most common bacterial genera in the calculi were used as models for the selection of PD exposure modes. It was found that the maximum time of photosensitizer accumulation depends on the structure of the bacterial cell wall: 30 min for Gram-negative strains and 60 min for Gram-positive ones. Optimal modes of PD exposure to antibiotic-resistant uropathogenic microorganisms were selected: 50 µg/mL Fotoditazin and 150 mW laser power. The maximal bactericidal activity of PDI against uropathogenic microorganisms was shown for Enterococcus faecalis, and Staphylococcus aureus. The bacteriostatic effect was found against Escherichia coli and Proteus mirabilis.

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