1
|
Torres-Rojas F, Muñoz D, Pía Canales C, Vargas IT. Bioprospecting for electrochemically active perchlorate-reducing microorganisms. Bioelectrochemistry 2022; 147:108171. [DOI: 10.1016/j.bioelechem.2022.108171] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 05/23/2022] [Accepted: 05/28/2022] [Indexed: 11/29/2022]
|
2
|
Cycil LM, DasSarma S, Pecher W, McDonald R, AbdulSalam M, Hasan F. Metagenomic Insights Into the Diversity of Halophilic Microorganisms Indigenous to the Karak Salt Mine, Pakistan. Front Microbiol 2020; 11:1567. [PMID: 32793134 PMCID: PMC7386132 DOI: 10.3389/fmicb.2020.01567] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 06/16/2020] [Indexed: 11/13/2022] Open
Abstract
Hypersaline regions are terrestrial analogs of the Earth’s primitive ecosystem and extraterrestrial environment. The salt range in Pakistan is considered among a few of the ancient salt deposits in the subcontinent. Karak salt mine is situated at the Northwest end in Pakistan. Despite the fact that halophiles initiated the formation of terrestrial ecosystems, their products and identities remain hidden. Some preliminary studies limited to culture-dependent isolations have been reported. Characterizing the microbiome that spans over centuries of ecosystem development is crucial, given their role in shaping landscape succession and biogeochemical cycles. Here, we used metagenomics techniques to explore the microbial diversity of the Karak salt mine. We used 16S rRNA Illumina amplicon sequencing to characterize the halophilic communities entrapped in Karak mine. The results were interpreted using Illumina Basespace, QIIME, and Cytoscape. Cultures were isolated at 16–25% salinity. Metagenomics data was consistent with our preliminary culturing data, indicating remarkable species to strain-level diversity of unique halophiles. A total of 107,099 (brine) and 122,679 (salt) reads were obtained. 16S rRNA based sequencing revealed a microbiome with bacteria (66% brine and 72% salt) dominated by Bacteroidetes and Proteobacteria with a strikingly high abundance of Archaea (18% brine and 13% salt). Alpha diversity has higher values in salt than in the brine. The study of the halophiles in the Karak salt mine provides clues for species contributing to the maintenance of biogeochemical cycles of the ecosystem. This is the first report of a metagenomic study of any hypersaline region of Pakistan.
Collapse
Affiliation(s)
- Leena Mavis Cycil
- Applied Environmental and Geomicrobiology Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan.,Institute of Marine and Environmental Technology, Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Shiladitya DasSarma
- Institute of Marine and Environmental Technology, Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Wolf Pecher
- Institute of Marine and Environmental Technology, Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, United States.,Yale Gordon College of Arts and Sciences, University of Baltimore, Baltimore, MD, United States
| | - Ryan McDonald
- Institute of Marine and Environmental Technology, Department of Marine Biotechnology, University of Maryland, Baltimore County, Baltimore, MD, United States
| | - Maria AbdulSalam
- Applied Environmental and Geomicrobiology Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Fariha Hasan
- Applied Environmental and Geomicrobiology Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan
| |
Collapse
|
3
|
Alqahtani MF, Bajracharya S, Katuri KP, Ali M, Ragab A, Michoud G, Daffonchio D, Saikaly PE. Enrichment of Marinobacter sp. and Halophilic Homoacetogens at the Biocathode of Microbial Electrosynthesis System Inoculated With Red Sea Brine Pool. Front Microbiol 2019; 10:2563. [PMID: 31787955 PMCID: PMC6855130 DOI: 10.3389/fmicb.2019.02563] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 10/23/2019] [Indexed: 11/13/2022] Open
Abstract
Homoacetogens are efficient CO2 fixing bacteria using H2 as electron donor to produce acetate. These organisms can be enriched at the biocathode of microbial electrosynthesis (MES) for electricity-driven CO2 reduction to acetate. Studies exploring homoacetogens in MES are mainly conducted using pure or mix-culture anaerobic inocula from samples with standard environmental conditions. Extreme marine environments host unique microbial communities including homoacetogens that may have unique capabilities due to their adaptation to harsh environmental conditions. Anaerobic deep-sea brine pools are hypersaline and metalliferous environments and homoacetogens can be expected to live in these environments due to their remarkable metabolic flexibility and energy-efficient biosynthesis. However, brine pools have never been explored as inocula for the enrichment of homacetogens in MES. Here we used the saline water from a Red Sea brine pool as inoculum for the enrichment of halophilic homoacetogens at the biocathode (-1 V vs. Ag/AgCl) of MES. Volatile fatty acids, especially acetate, along with hydrogen gas were produced in MES systems operated at 25 and 10% salinity. Acetate concentration increased when MES was operated at a lower salinity ∼3.5%, representing typical seawater salinity. Amplicon sequencing and genome-centric metagenomics of matured cathodic biofilm showed dominance of the genus Marinobacter and phylum Firmicutes at all tested salinities. Seventeen high-quality draft metagenome-assembled genomes (MAGs) were extracted from the biocathode samples. The recovered MAGs accounted for 87 ± 4% of the quality filtered sequence reads. Genome analysis of the MAGs suggested CO2 fixation via Wood-Ljundahl pathway by members of the phylum Firmicutes and the fixed CO2 was possibly utilized by Marinobacter sp. for growth by consuming O2 escaping from the anode to the cathode for respiration. The enrichment of Marinobacter sp. with homoacetogens was only possible because of the specific cathodic environment in MES. These findings suggest that in organic carbon-limited saline environments, Marinobacter spp. can live in consortia with CO2 fixing bacteria such as homoacetogens, which can provide them with fixed carbon as a source of carbon and energy.
Collapse
Affiliation(s)
- Manal F Alqahtani
- King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Biological and Environmental Science and Engineering Division, Thuwal, Saudi Arabia
| | - Suman Bajracharya
- King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Biological and Environmental Science and Engineering Division, Thuwal, Saudi Arabia
| | - Krishna P Katuri
- King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Biological and Environmental Science and Engineering Division, Thuwal, Saudi Arabia
| | - Muhammad Ali
- King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Biological and Environmental Science and Engineering Division, Thuwal, Saudi Arabia
| | - Ala'a Ragab
- King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Biological and Environmental Science and Engineering Division, Thuwal, Saudi Arabia
| | - Grégoire Michoud
- King Abdullah University of Science and Technology, Red Sea Research Center, Biological and Environmental Science and Engineering Division, Thuwal, Saudi Arabia
| | - Daniele Daffonchio
- King Abdullah University of Science and Technology, Red Sea Research Center, Biological and Environmental Science and Engineering Division, Thuwal, Saudi Arabia
| | - Pascal E Saikaly
- King Abdullah University of Science and Technology, Water Desalination and Reuse Center, Biological and Environmental Science and Engineering Division, Thuwal, Saudi Arabia
| |
Collapse
|
4
|
Bird LJ, Wang Z, Malanoski AP, Onderko EL, Johnson BJ, Moore MH, Phillips DA, Chu BJ, Doyle JF, Eddie BJ, Glaven SM. Development of a Genetic System for Marinobacter atlanticus CP1 ( sp. nov.), a Wax Ester Producing Strain Isolated From an Autotrophic Biocathode. Front Microbiol 2018; 9:3176. [PMID: 30622527 PMCID: PMC6308636 DOI: 10.3389/fmicb.2018.03176] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 12/07/2018] [Indexed: 11/13/2022] Open
Abstract
Here, we report on the development of a genetic system for Marinobacter sp. strain CP1, previously isolated from the Biocathode MCL community and shown to oxidize iron and grow as a cathodic biofilm. Sequence analysis of the small and large subunits of the 16S rRNA gene of CP1, as well as comparison of select conserved proteins, indicate that it is most closely related to Marinobacter adhaerens HP15 and Marinobacter sp. ES.042. In silico DNA–DNA hybridization using the genome-to-genome distance calculator (GGDC) predicts CP1 to be a new species of Marinobacter described here as Marinobacter atlanticus. CP1 is competent for transformation with plasmid DNA using conjugation with Escherichia coli donor strain WM3064 and constitutive expression of green fluorescent protein (GFP) is stable in the absence of antibiotic selection. Targeted double deletion mutagenesis of homologs for the M. aquaeoli fatty acyl-CoA reductase (acrB) and fatty aldehyde reductase (farA) genes resulted in a loss of production of wax esters; however, single deletion mutants for either gene resulted in an increase in total wax esters recovered. Genetic tools presented here for CP1 will enable further exploration of wax ester synthesis for biotechnological applications, as well as furthering our efforts to understand the role of CP1 within the Biocathode MCL community.
Collapse
Affiliation(s)
- Lina J Bird
- National Research Council, Washington, DC, United States
| | - Zheng Wang
- Center for Biomolecular Science and Engineering, United States Naval Research Laboratory, Washington, DC, United States
| | - Anthony P Malanoski
- Center for Biomolecular Science and Engineering, United States Naval Research Laboratory, Washington, DC, United States
| | | | - Brandy J Johnson
- Center for Biomolecular Science and Engineering, United States Naval Research Laboratory, Washington, DC, United States
| | - Martin H Moore
- Center for Biomolecular Science and Engineering, United States Naval Research Laboratory, Washington, DC, United States
| | - Daniel A Phillips
- American Society For Engineering Education, Washington, DC, United States
| | - Brandon J Chu
- Fischell Department of Bioengineering, University of Maryland, College Park, College Park, MD, United States
| | | | - Brian J Eddie
- Center for Biomolecular Science and Engineering, United States Naval Research Laboratory, Washington, DC, United States
| | - Sarah M Glaven
- Center for Biomolecular Science and Engineering, United States Naval Research Laboratory, Washington, DC, United States
| |
Collapse
|
5
|
Draft Genome Sequence of Marinobacter vinifirmus Type Strain FB1. GENOME ANNOUNCEMENTS 2017; 5:5/39/e01058-17. [PMID: 28963221 PMCID: PMC5624767 DOI: 10.1128/genomea.01058-17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The gammaproteobacterium Marinobacter vinifirmus is associated with moderately saline environments and is often found in marine ecosystems. Here, we report the draft genome sequence of M. vinifirmus type strain FB1 (3.8 Mbp, 3,588 predicted genes). The presented sequence will improve our understanding of the taxonomy and evolution of the genus Marinobacter.
Collapse
|
6
|
Okpala GN, Chen C, Fida T, Voordouw G. Effect of Thermophilic Nitrate Reduction on Sulfide Production in High Temperature Oil Reservoir Samples. Front Microbiol 2017; 8:1573. [PMID: 28900416 PMCID: PMC5581841 DOI: 10.3389/fmicb.2017.01573] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Accepted: 08/03/2017] [Indexed: 01/25/2023] Open
Abstract
Oil fields can experience souring, the reduction of sulfate to sulfide by sulfate-reducing microorganisms. At the Terra Nova oil field near Canada's east coast, with a reservoir temperature of 95°C, souring was indicated by increased hydrogen sulfide in produced waters (PW). Microbial community analysis by 16S rRNA gene sequencing showed the hyperthermophilic sulfate-reducing archaeon Archaeoglobus in Terra Nova PWs. Growth enrichments in sulfate-containing media at 55-70°C with lactate or volatile fatty acids yielded the thermophilic sulfate-reducing bacterium (SRB) Desulfotomaculum. Enrichments at 30-45°C in nitrate-containing media indicated the presence of mesophilic nitrate-reducing bacteria (NRB), which reduce nitrate without accumulation of nitrite, likely to N2. Thermophilic NRB (tNRB) of the genera Marinobacter and Geobacillus were detected and isolated at 30-50°C and 40-65°C, respectively, and only reduced nitrate to nitrite. Added nitrite strongly inhibited the isolated thermophilic SRB (tSRB) and tNRB and SRB could not be maintained in co-culture. Inhibition of tSRB by nitrate in batch and continuous cultures required inoculation with tNRB. The results suggest that nitrate injected into Terra Nova is reduced to N2 at temperatures up to 45°C but to nitrite only in zones from 45 to 65°C. Since the hotter zones of the reservoir (65-80°C) are inhabited by thermophilic and hyperthermophilic sulfate reducers, souring at these temperatures might be prevented by nitrite production if nitrate-reducing zones of the system could be maintained at 45-65°C.
Collapse
Affiliation(s)
- Gloria N. Okpala
- Petroleum Microbiology Research Group, Department of Biological Sciences, University of Calgary, CalgaryAB, Canada
| | - Chuan Chen
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of TechnologyHarbin, China
| | - Tekle Fida
- Petroleum Microbiology Research Group, Department of Biological Sciences, University of Calgary, CalgaryAB, Canada
| | - Gerrit Voordouw
- Petroleum Microbiology Research Group, Department of Biological Sciences, University of Calgary, CalgaryAB, Canada
| |
Collapse
|