101
|
Predominance and Metabolic Potential of Halanaerobium spp. in Produced Water from Hydraulically Fractured Marcellus Shale Wells. Appl Environ Microbiol 2017; 83:AEM.02659-16. [PMID: 28159795 DOI: 10.1128/aem.02659-16] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 01/28/2017] [Indexed: 11/20/2022] Open
Abstract
Microbial activity in the produced water from hydraulically fractured oil and gas wells may potentially interfere with hydrocarbon production and cause damage to the well and surface infrastructure via corrosion, sulfide release, and fouling. In this study, we surveyed the microbial abundance and community structure of produced water sampled from 42 Marcellus Shale wells in southwestern Pennsylvania (well age ranged from 150 to 1,846 days) to better understand the microbial diversity of produced water. We sequenced the V4 region of the 16S rRNA gene to assess taxonomy and utilized quantitative PCR (qPCR) to evaluate the microbial abundance across all 42 produced water samples. Bacteria of the order Halanaerobiales were found to be the most abundant organisms in the majority of the produced water samples, emphasizing their previously suggested role in hydraulic fracturing-related microbial activity. Statistical analyses identified correlations between well age and biocide formulation and the microbial community, in particular, the relative abundance of Halanaerobiales We further investigated the role of members of the order Halanaerobiales in produced water by reconstructing and annotating a Halanaerobium draft genome (named MDAL1), using shotgun metagenomic sequencing and metagenomic binning. The recovered draft genome was found to be closely related to the species H. congolense, an oil field isolate, and Halanaerobium sp. strain T82-1, also recovered from hydraulic fracturing produced water. Reconstruction of metabolic pathways revealed Halanaerobium sp. strain MDAL1 to have the potential for acid production, thiosulfate reduction, and biofilm formation, suggesting it to have the ability to contribute to corrosion, souring, and biofouling events in the hydraulic fracturing infrastructure.IMPORTANCE There are an estimated 15,000 unconventional gas wells in the Marcellus Shale region, each generating up to 8,000 liters of hypersaline produced water per day throughout its lifetime (K. Gregory, R. Vidic, and D. Dzombak, Elements 7:181-186, 2011, https://doi.org/10.2113/gselements.7.3.181; J. Arthur, B. Bohm, and M. Layne, Gulf Coast Assoc Geol Soc Trans 59:49-59, 2009; https://www.marcellusgas.org/index.php). Microbial activity in produced waters could lead to issues with corrosion, fouling, and souring, potentially interfering with hydraulic fracturing operations. Previous studies have found microorganisms contributing to corrosion, fouling, and souring to be abundant across produced water samples from hydraulically fractured wells; however, these findings were based on a limited number of samples and well sites. In this study, we investigated the microbial community structure in produced water samples from 42 unconventional Marcellus Shale wells, confirming the dominance of the genus Halanaerobium in produced water and its metabolic potential for acid and sulfide production and biofilm formation.
Collapse
|
102
|
Nitrate reduction in Haloferax alexandrinus: the case of assimilatory nitrate reductase. Extremophiles 2017; 21:551-561. [DOI: 10.1007/s00792-017-0924-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Accepted: 02/27/2017] [Indexed: 11/25/2022]
|
103
|
Wakai S, Abe A, Fujii S, Nakasone K, Sambongi Y. Pyrophosphate hydrolysis in the extremely halophilic archaeon Haloarcula japonica is catalyzed by a single enzyme with a broad ionic strength range. Extremophiles 2017; 21:471-477. [DOI: 10.1007/s00792-017-0917-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 01/27/2017] [Indexed: 11/30/2022]
|
104
|
Dopson M, Holmes DS, Lazcano M, McCredden TJ, Bryan CG, Mulroney KT, Steuart R, Jackaman C, Watkin ELJ. Multiple Osmotic Stress Responses in Acidihalobacter prosperus Result in Tolerance to Chloride Ions. Front Microbiol 2017; 7:2132. [PMID: 28111571 PMCID: PMC5216662 DOI: 10.3389/fmicb.2016.02132] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/19/2016] [Indexed: 11/16/2022] Open
Abstract
Extremely acidophilic microorganisms (pH optima for growth of ≤3) are utilized for the extraction of metals from sulfide minerals in the industrial biotechnology of “biomining.” A long term goal for biomining has been development of microbial consortia able to withstand increased chloride concentrations for use in regions where freshwater is scarce. However, when challenged by elevated salt, acidophiles experience both osmotic stress and an acidification of the cytoplasm due to a collapse of the inside positive membrane potential, leading to an influx of protons. In this study, we tested the ability of the halotolerant acidophile Acidihalobacter prosperus to grow and catalyze sulfide mineral dissolution in elevated concentrations of salt and identified chloride tolerance mechanisms in Ac. prosperus as well as the chloride susceptible species, Acidithiobacillus ferrooxidans. Ac. prosperus had optimum iron oxidation at 20 g L−1 NaCl while At. ferrooxidans iron oxidation was inhibited in the presence of 6 g L−1 NaCl. The tolerance to chloride in Ac. prosperus was consistent with electron microscopy, determination of cell viability, and bioleaching capability. The Ac. prosperus proteomic response to elevated chloride concentrations included the production of osmotic stress regulators that potentially induced production of the compatible solute, ectoine uptake protein, and increased iron oxidation resulting in heightened electron flow to drive proton export by the F0F1 ATPase. In contrast, At. ferrooxidans responded to low levels of Cl− with a generalized stress response, decreased iron oxidation, and an increase in central carbon metabolism. One potential adaptation to high chloride in the Ac. prosperus Rus protein involved in ferrous iron oxidation was an increase in the negativity of the surface potential of Rus Form I (and Form II) that could help explain how it can be active under elevated chloride concentrations. These data have been used to create a model of chloride tolerance in the salt tolerant and susceptible species Ac. prosperus and At. ferrooxidans, respectively.
Collapse
Affiliation(s)
- Mark Dopson
- Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University Kalmar, Sweden
| | - David S Holmes
- Facultad de Ciencias Biologicas, Universidad Andres BelloSantiago, Chile; Center for Bioinformatics and Genome Biology, Fundacion Ciencia y VidaSantiago, Chile
| | - Marcelo Lazcano
- Facultad de Ciencias Biologicas, Universidad Andres BelloSantiago, Chile; Center for Bioinformatics and Genome Biology, Fundacion Ciencia y VidaSantiago, Chile
| | - Timothy J McCredden
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University Perth, WA, Australia
| | - Christopher G Bryan
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University Perth, WA, Australia
| | - Kieran T Mulroney
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University Perth, WA, Australia
| | - Robert Steuart
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University Perth, WA, Australia
| | - Connie Jackaman
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University Perth, WA, Australia
| | - Elizabeth L J Watkin
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University Perth, WA, Australia
| |
Collapse
|
105
|
Harding T, Brown MW, Simpson AGB, Roger AJ. Osmoadaptative Strategy and Its Molecular Signature in Obligately Halophilic Heterotrophic Protists. Genome Biol Evol 2016; 8:2241-58. [PMID: 27412608 PMCID: PMC4987115 DOI: 10.1093/gbe/evw152] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/22/2016] [Indexed: 01/17/2023] Open
Abstract
Halophilic microbes living in hypersaline environments must counteract the detrimental effects of low water activity and salt interference. Some halophilic prokaryotes equilibrate their intracellular osmotic strength with the extracellular milieu by importing inorganic solutes, mainly potassium. These "salt-in" organisms characteristically have proteins that are highly enriched with acidic and hydrophilic residues. In contrast, "salt-out" halophiles accumulate large amounts of organic solutes like amino acids, sugars and polyols, and lack a strong signature of halophilicity in the amino acid composition of cytoplasmic proteins. Studies to date have examined halophilic prokaryotes, yeasts, or algae, thus virtually nothing is known about the molecular adaptations of the other eukaryotic microbes, that is, heterotrophic protists (protozoa), that also thrive in hypersaline habitats. We conducted transcriptomic investigations to unravel the molecular adaptations of two obligately halophilic protists, Halocafeteria seosinensis and Pharyngomonas kirbyi Their predicted cytoplasmic proteomes showed increased hydrophilicity compared with marine protists. Furthermore, analysis of reconstructed ancestral sequences suggested that, relative to mesophiles, proteins in halophilic protists have undergone fewer substitutions from hydrophilic to hydrophobic residues since divergence from their closest relatives. These results suggest that these halophilic protists have a higher intracellular salt content than marine protists. However, absence of the acidic signature of salt-in microbes suggests that Haloc. seosinensis and P. kirbyi utilize organic osmolytes to maintain osmotic equilibrium. We detected increased expression of enzymes involved in synthesis and transport of organic osmolytes, namely hydroxyectoine and myo-inositol, at maximal salt concentration for growth in Haloc. seosinensis, suggesting possible candidates for these inferred organic osmolytes.
Collapse
Affiliation(s)
- Tommy Harding
- Department of Biochemistry and Molecular Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Matthew W Brown
- Department of Biological Sciences, Mississippi State University
| | - Alastair G B Simpson
- Department of Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Andrew J Roger
- Department of Biochemistry and Molecular Biology, Centre for Comparative Genomics and Evolutionary Bioinformatics, Dalhousie University, Halifax, Nova Scotia, Canada
| |
Collapse
|
106
|
Exopolysaccharides of Halophilic Microorganisms: An Overview. Ind Biotechnol (New Rochelle N Y) 2016. [DOI: 10.1201/b19347-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
107
|
Oren A. Hans Georg Trüper (1936-2016) and His Contributions to Halophile Research. Life (Basel) 2016; 6:E19. [PMID: 27187481 PMCID: PMC4931456 DOI: 10.3390/life6020019] [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] [Received: 04/28/2016] [Revised: 05/06/2016] [Accepted: 05/06/2016] [Indexed: 11/17/2022] Open
Abstract
Prof. Hans Georg Trüper, one of the most important scientists in the field of halophile research, passed away on 9 March 2016 at the age of 79. I here present a brief obituary with special emphasis on Prof. Trüper's contributions to our understanding of the halophilic prokaryotes and their adaptations to life in hypersaline environments. He has pioneered the study of the halophilic anoxygenic phototrophic sulfur bacteria of the Ectothiorhodospira-Halorhodospira group. Some of the species he and his group isolated from hypersaline and haloalkaline environments have become model organisms for the study of the mechanisms of haloadaptation: the functions of three major organic compounds - glycine betaine, ectoine, and trehalose - known to serve as "compatible solutes" in halophilic members of the Bacteria domain, were discovered during studies of these anoxygenic phototrophs. Prof. Trüper's studies of hypersaline alkaline environments in Egypt also led to the isolation of the first known extremely halophilic archaeon (Natronomonas pharaonis). The guest editors dedicate this special volume of Life to the memory of Prof. Hans Georg Trüper.
Collapse
Affiliation(s)
- Aharon Oren
- Department of Plant and Environmental Sciences, The Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem 91904, Israel.
| |
Collapse
|
108
|
Scholz A, Stahl J, de Berardinis V, Müller V, Averhoff B. Osmotic stress response in Acinetobacter baylyi: identification of a glycine-betaine biosynthesis pathway and regulation of osmoadaptive choline uptake and glycine-betaine synthesis through a choline-responsive BetI repressor. ENVIRONMENTAL MICROBIOLOGY REPORTS 2016; 8:316-322. [PMID: 26910138 DOI: 10.1111/1758-2229.12382] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 11/21/2015] [Indexed: 06/05/2023]
Abstract
Acinetobacter baylyi, a ubiquitous soil bacterium, can cope with high salinity by uptake of choline as precursor of the compatible solute glycine betaine. Here, we report on the identification of a choline dehydrogenase (BetA) and a glycine betaine aldehyde dehydrogenase (BetB) mediating the oxidation of choline to glycine betaine. The betAB genes were found to form an operon together with the potential transcriptional regulator betI. The transcription of the betIBA operon and the two recently identified choline transporters was upregulated in response to choline and choline plus salt. The finding that the osmo-independent transporter BetT1 undergoes a higher upregulation in response to choline alone than betT2 suggests that BetT1 does not primarily function in osmoadaptation. Electrophoretic mobility shift assays led to the conclusion that BetI mediates transcriptional regulation of both, the betIBA gene operon and the choline transporters. BetI was released from the DNA in response to choline which together with the transcriptional upregulation of the bet genes in the presence of choline suggests that BetI is a choline sensing transcriptional repressor.
Collapse
Affiliation(s)
- Anica Scholz
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Julia Stahl
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt, Frankfurt am Main, Germany
| | | | - Volker Müller
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Beate Averhoff
- Department of Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Johann Wolfgang Goethe University Frankfurt, Frankfurt am Main, Germany
| |
Collapse
|
109
|
de la Vega M, Sayago A, Ariza J, Barneto AG, León R. Characterization of a bacterioruberin-producing Haloarchaea isolated from the marshlands of the Odiel river in the southwest of Spain. Biotechnol Prog 2016; 32:592-600. [DOI: 10.1002/btpr.2248] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 02/08/2016] [Indexed: 11/08/2022]
Affiliation(s)
- Marta de la Vega
- Dept. of Chemistry; Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR) and CEICAMBIO, University of Huelva; Huelva Spain
| | - Ana Sayago
- Dept. of Chemistry; Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR) and CEICAMBIO, University of Huelva; Huelva Spain
| | - José Ariza
- Dept. of Chemistry; Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR) and CEICAMBIO, University of Huelva; Huelva Spain
| | - Agustín G. Barneto
- Dept. of Chemistry; Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR) and CEICAMBIO, University of Huelva; Huelva Spain
| | - Rosa León
- Dept. of Chemistry; Faculty of Experimental Sciences, Marine International Campus of Excellence (CEIMAR) and CEICAMBIO, University of Huelva; Huelva Spain
| |
Collapse
|
110
|
Vavourakis CD, Ghai R, Rodriguez-Valera F, Sorokin DY, Tringe SG, Hugenholtz P, Muyzer G. Metagenomic Insights into the Uncultured Diversity and Physiology of Microbes in Four Hypersaline Soda Lake Brines. Front Microbiol 2016; 7:211. [PMID: 26941731 PMCID: PMC4766312 DOI: 10.3389/fmicb.2016.00211] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 02/08/2016] [Indexed: 11/13/2022] Open
Abstract
Soda lakes are salt lakes with a naturally alkaline pH due to evaporative concentration of sodium carbonates in the absence of major divalent cations. Hypersaline soda brines harbor microbial communities with a high species- and strain-level archaeal diversity and a large proportion of still uncultured poly-extremophiles compared to neutral brines of similar salinities. We present the first "metagenomic snapshots" of microbial communities thriving in the brines of four shallow soda lakes from the Kulunda Steppe (Altai, Russia) covering a salinity range from 170 to 400 g/L. Both amplicon sequencing of 16S rRNA fragments and direct metagenomic sequencing showed that the top-level taxa abundance was linked to the ambient salinity: Bacteroidetes, Alpha-, and Gamma-proteobacteria were dominant below a salinity of 250 g/L, Euryarchaeota at higher salinities. Within these taxa, amplicon sequences related to Halorubrum, Natrinema, Gracilimonas, purple non-sulfur bacteria (Rhizobiales, Rhodobacter, and Rhodobaca) and chemolithotrophic sulfur oxidizers (Thioalkalivibrio) were highly abundant. Twenty-four draft population genomes from novel members and ecotypes within the Nanohaloarchaea, Halobacteria, and Bacteroidetes were reconstructed to explore their metabolic features, environmental abundance and strategies for osmotic adaptation. The Halobacteria- and Bacteroidetes-related draft genomes belong to putative aerobic heterotrophs, likely with the capacity to ferment sugars in the absence of oxygen. Members from both taxonomic groups are likely involved in primary organic carbon degradation, since some of the reconstructed genomes encode the ability to hydrolyze recalcitrant substrates, such as cellulose and chitin. Putative sodium-pumping rhodopsins were found in both a Flavobacteriaceae- and a Chitinophagaceae-related draft genome. The predicted proteomes of both the latter and a Rhodothermaceae-related draft genome were indicative of a "salt-in" strategy of osmotic adaptation. The primary catabolic and respiratory pathways shared among all available reference genomes of Nanohaloarchaea and our novel genome reconstructions remain incomplete, but point to a primarily fermentative lifestyle. Encoded xenorhodopsins found in most drafts suggest that light plays an important role in the ecology of Nanohaloarchaea. Putative encoded halolysins and laccase-like oxidases might indicate the potential for extracellular degradation of proteins and peptides, and phenolic or aromatic compounds.
Collapse
Affiliation(s)
- Charlotte D. Vavourakis
- Microbial Systems Ecology, Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of AmsterdamAmsterdam, Netherlands
| | - Rohit Ghai
- Evolutionary Genomics Group, Departamento de Producción Vegetal y Microbiología, Universidad Miguel HernándezSan Juan de Alicante, Spain
- Department of Aquatic Microbial Ecology, Biology Centre of the Czech Academy of Sciences, Institute of HydrobiologyČeské Budějovice, Czech Republic
| | - Francisco Rodriguez-Valera
- Evolutionary Genomics Group, Departamento de Producción Vegetal y Microbiología, Universidad Miguel HernándezSan Juan de Alicante, Spain
| | - Dimitry Y. Sorokin
- Research Centre of Biotechnology, Winogradsky Institute of Microbiology, Russian Academy of SciencesMoscow, Russia
- Department of Biotechnology, Delft University of TechnologyDelft, Netherlands
| | | | - Philip Hugenholtz
- Australian Centre for Ecogenomics, School of Chemistry and Molecular Biosciences and Institute for Molecular Bioscience, The University of QueenslandBrisbane, QLD, Australia
| | - Gerard Muyzer
- Microbial Systems Ecology, Department of Aquatic Microbiology, Institute for Biodiversity and Ecosystem Dynamics, University of AmsterdamAmsterdam, Netherlands
| |
Collapse
|
111
|
Sánchez-Nieves R, Facciotti M, Saavedra-Collado S, Dávila-Santiago L, Rodríguez-Carrero R, Montalvo-Rodríguez R. Draft genome of Haloarcula rubripromontorii strain SL3, a novel halophilic archaeon isolated from the solar salterns of Cabo Rojo, Puerto Rico. GENOMICS DATA 2016; 7:287-9. [PMID: 26981428 PMCID: PMC4778667 DOI: 10.1016/j.gdata.2016.02.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 02/05/2016] [Indexed: 11/30/2022]
Abstract
The genus Haloarcula belongs to the family Halobacteriaceae which currently has 10 valid species. Here we report the draft genome sequence of strain SL3, a new species within this genus, isolated from the Solar Salterns of Cabo Rojo, Puerto Rico. Genome assembly performed using NGEN Assembler resulted in 18 contigs (N50 = 601,911 bp), the largest of which contains 1,023,775 bp. The genome consists of 3.97 MB and has a GC content of 61.97%. Like all species of Haloarcula, the genome encodes heterogeneous copies of the small subunit ribosomal RNA. In addition, the genome includes 6 rRNAs, 48 tRNAs, and 3797 protein coding sequences. Several carbohydrate-active enzymes genes were found, as well as enzymes involved in the dihydroxyacetone processing pathway which are not found in other Haloarcula species. The NCBI accession number for this genome is LIUF00000000 and the strain deposit number is CECT9001.
Collapse
Affiliation(s)
- Rubén Sánchez-Nieves
- Biology Department, University of Puerto Rico, Mayaguez, Box 9000, 00681-9000, Puerto Rico
| | - Marc Facciotti
- Biomedical Engineering and Genome Center, 451 Health Sciences Drive, Davis, CA, 95618, United States
| | - Sofía Saavedra-Collado
- Biology Department, University of Puerto Rico, Mayaguez, Box 9000, 00681-9000, Puerto Rico
| | | | - Roy Rodríguez-Carrero
- Biology Department, University of Puerto Rico, Mayaguez, Box 9000, 00681-9000, Puerto Rico
| | | |
Collapse
|
112
|
Widderich N, Czech L, Elling FJ, Könneke M, Stöveken N, Pittelkow M, Riclea R, Dickschat JS, Heider J, Bremer E. Strangers in the archaeal world: osmostress-responsive biosynthesis of ectoine and hydroxyectoine by the marine thaumarchaeon Nitrosopumilus maritimus. Environ Microbiol 2016; 18:1227-48. [PMID: 26636559 DOI: 10.1111/1462-2920.13156] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 11/19/2015] [Accepted: 11/27/2015] [Indexed: 11/29/2022]
Abstract
Ectoine and hydroxyectoine are compatible solutes widely synthesized by members of the Bacteria to cope with high osmolarity surroundings. Inspection of 557 archaeal genomes revealed that only 12 strains affiliated with the Nitrosopumilus, Methanothrix or Methanobacterium genera harbour ectoine/hydroxyectoine gene clusters. Phylogenetic considerations suggest that these Archaea have acquired these genes through horizontal gene transfer events. Using the Thaumarchaeon 'Candidatus Nitrosopumilus maritimus' as an example, we demonstrate that the transcription of its ectABCD genes is osmotically induced and functional since it leads to the production of both ectoine and hydroxyectoine. The ectoine synthase and the ectoine hydroxylase were biochemically characterized, and their properties resemble those of their counterparts from Bacteria. Transcriptional analysis of osmotically stressed 'Ca. N. maritimus' cells demonstrated that they possess an ectoine/hydroxyectoine gene cluster (hyp-ectABCD-mscS) different from those recognized previously since it contains a gene for an MscS-type mechanosensitive channel. Complementation experiments with an Escherichia coli mutant lacking all known mechanosensitive channel proteins demonstrated that the (Nm)MscS protein is functional. Hence, 'Ca. N. maritimus' cells cope with high salinity not only through enhanced synthesis of osmostress-protective ectoines but they already prepare themselves simultaneously for an eventually occurring osmotic down-shock by enhancing the production of a safety-valve (NmMscS).
Collapse
Affiliation(s)
- Nils Widderich
- Laboratory for Molecular Microbiology, Department of Biology, Philipps-University, Karl-von-Frisch Str. 8, D-35043, Marburg, Germany
| | - Laura Czech
- Laboratory for Molecular Microbiology, Department of Biology, Philipps-University, Karl-von-Frisch Str. 8, D-35043, Marburg, Germany
| | - Felix J Elling
- Organic Geochemistry Group, MARUM - Center for Marine Environmental Sciences, University of Bremen, PO Box 330 440, D-28334, Bremen, Germany
| | - Martin Könneke
- Organic Geochemistry Group, MARUM - Center for Marine Environmental Sciences, University of Bremen, PO Box 330 440, D-28334, Bremen, Germany
| | - Nadine Stöveken
- Laboratory for Molecular Microbiology, Department of Biology, Philipps-University, Karl-von-Frisch Str. 8, D-35043, Marburg, Germany.,LOEWE-Center for Synthetic Microbiology, Philipps-University Marburg, Hans-Meerwein-Str. 6, D-35043, Marburg, Germany
| | - Marco Pittelkow
- Laboratory for Molecular Microbiology, Department of Biology, Philipps-University, Karl-von-Frisch Str. 8, D-35043, Marburg, Germany
| | - Ramona Riclea
- Kekulé-Institut for Organic Chemistry and Biochemistry, Friedrich-Wilhelms-University Bonn, Gerhard-Domagk Str. 1, D-53121, Bonn, Germany.,Institute of Organic Chemistry, TU Braunschweig, Hagenring 30, D-38106, Braunschweig, Germany
| | - Jeroen S Dickschat
- Kekulé-Institut for Organic Chemistry and Biochemistry, Friedrich-Wilhelms-University Bonn, Gerhard-Domagk Str. 1, D-53121, Bonn, Germany.,Institute of Organic Chemistry, TU Braunschweig, Hagenring 30, D-38106, Braunschweig, Germany
| | - Johann Heider
- Laboratory for Molecular Microbiology, Department of Biology, Philipps-University, Karl-von-Frisch Str. 8, D-35043, Marburg, Germany.,LOEWE-Center for Synthetic Microbiology, Philipps-University Marburg, Hans-Meerwein-Str. 6, D-35043, Marburg, Germany
| | - Erhard Bremer
- Laboratory for Molecular Microbiology, Department of Biology, Philipps-University, Karl-von-Frisch Str. 8, D-35043, Marburg, Germany.,LOEWE-Center for Synthetic Microbiology, Philipps-University Marburg, Hans-Meerwein-Str. 6, D-35043, Marburg, Germany
| |
Collapse
|
113
|
Mwirichia R, Alam I, Rashid M, Vinu M, Ba-Alawi W, Anthony Kamau A, Kamanda Ngugi D, Göker M, Klenk HP, Bajic V, Stingl U. Metabolic traits of an uncultured archaeal lineage--MSBL1--from brine pools of the Red Sea. Sci Rep 2016; 6:19181. [PMID: 26758088 PMCID: PMC4725937 DOI: 10.1038/srep19181] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 12/04/2015] [Indexed: 11/24/2022] Open
Abstract
The candidate Division MSBL1 (Mediterranean Sea Brine Lakes 1) comprises a monophyletic group of uncultured archaea found in different hypersaline environments. Previous studies propose methanogenesis as the main metabolism. Here, we describe a metabolic reconstruction of MSBL1 based on 32 single-cell amplified genomes from Brine Pools of the Red Sea (Atlantis II, Discovery, Nereus, Erba and Kebrit). Phylogeny based on rRNA genes as well as conserved single copy genes delineates the group as a putative novel lineage of archaea. Our analysis shows that MSBL1 may ferment glucose via the Embden-Meyerhof-Parnas pathway. However, in the absence of organic carbon, carbon dioxide may be fixed via the ribulose bisphosphate carboxylase, Wood-Ljungdahl pathway or reductive TCA cycle. Therefore, based on the occurrence of genes for glycolysis, absence of the core genes found in genomes of all sequenced methanogens and the phylogenetic position, we hypothesize that the MSBL1 are not methanogens, but probably sugar-fermenting organisms capable of autotrophic growth. Such a mixotrophic lifestyle would confer survival advantage (or possibly provide a unique narrow niche) when glucose and other fermentable sugars are not available.
Collapse
Affiliation(s)
- Romano Mwirichia
- Red Sea Research Center, King Abdullah University of Science and
Technology (KAUST), Thuwal, Saudi Arabia
| | - Intikhab Alam
- Computational Bioscience Research Center, King Abdullah
University of Science and Technology (KAUST), Thuwal,
Saudi Arabia
| | - Mamoon Rashid
- Red Sea Research Center, King Abdullah University of Science and
Technology (KAUST), Thuwal, Saudi Arabia
| | - Manikandan Vinu
- Red Sea Research Center, King Abdullah University of Science and
Technology (KAUST), Thuwal, Saudi Arabia
| | - Wail Ba-Alawi
- Computational Bioscience Research Center, King Abdullah
University of Science and Technology (KAUST), Thuwal,
Saudi Arabia
| | - Allan Anthony Kamau
- Computational Bioscience Research Center, King Abdullah
University of Science and Technology (KAUST), Thuwal,
Saudi Arabia
| | - David Kamanda Ngugi
- Red Sea Research Center, King Abdullah University of Science and
Technology (KAUST), Thuwal, Saudi Arabia
| | - Markus Göker
- German Collection for Microorganisms and Cell Cultures GmbH
(DSMZ), Inhoffenstraße 7b, 38124
Braunschweig, Germany
| | - Hans-Peter Klenk
- School of Biology, Newcastle University, Newcastle
upon Tyne, United Kingdom
| | - Vladimir Bajic
- Computational Bioscience Research Center, King Abdullah
University of Science and Technology (KAUST), Thuwal,
Saudi Arabia
| | - Ulrich Stingl
- Red Sea Research Center, King Abdullah University of Science and
Technology (KAUST), Thuwal, Saudi Arabia
| |
Collapse
|
114
|
Dopson M, Ni G, Sleutels THJA. Possibilities for extremophilic microorganisms in microbial electrochemical systems. FEMS Microbiol Rev 2015; 40:164-81. [PMID: 26474966 PMCID: PMC4802824 DOI: 10.1093/femsre/fuv044] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2015] [Indexed: 11/12/2022] Open
Abstract
Microbial electrochemical systems exploit the metabolism of microorganisms to generate electrical energy or a useful product. In the past couple of decades, the application of microbial electrochemical systems has increased from the use of wastewaters to produce electricity to a versatile technology that can use numerous sources for the extraction of electrons on the one hand, while on the other hand these electrons can be used to serve an ever increasing number of functions. Extremophilic microorganisms grow in environments that are hostile to most forms of life and their utilization in microbial electrochemical systems has opened new possibilities to oxidize substrates in the anode and produce novel products in the cathode. For example, extremophiles can be used to oxidize sulfur compounds in acidic pH to remediate wastewaters, generate electrical energy from marine sediment microbial fuel cells at low temperatures, desalinate wastewaters and act as biosensors of low amounts of organic carbon. In this review, we will discuss the recent advances that have been made in using microbial catalysts under extreme conditions and show possible new routes that extremophilic microorganisms open for microbial electrochemical systems.
Collapse
Affiliation(s)
- Mark Dopson
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, SE-391 82 Kalmar, Sweden
| | - Gaofeng Ni
- Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, SE-391 82 Kalmar, Sweden
| | - Tom H J A Sleutels
- Wetsus, European Centre of Excellence for Sustainable Water Technology, 8911 MA Leeuwarden, The Netherlands
| |
Collapse
|
115
|
Mirete S, Mora-Ruiz MR, Lamprecht-Grandío M, de Figueras CG, Rosselló-Móra R, González-Pastor JE. Salt resistance genes revealed by functional metagenomics from brines and moderate-salinity rhizosphere within a hypersaline environment. Front Microbiol 2015; 6:1121. [PMID: 26528268 PMCID: PMC4602150 DOI: 10.3389/fmicb.2015.01121] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 09/28/2015] [Indexed: 11/13/2022] Open
Abstract
Hypersaline environments are considered one of the most extreme habitats on earth and microorganisms have developed diverse molecular mechanisms of adaptation to withstand these conditions. The present study was aimed at identifying novel genes from the microbial communities of a moderate-salinity rhizosphere and brine from the Es Trenc saltern (Mallorca, Spain), which could confer increased salt resistance to Escherichia coli. The microbial diversity assessed by pyrosequencing of 16S rRNA gene libraries revealed the presence of communities that are typical in such environments and the remarkable presence of three bacterial groups never revealed as major components of salt brines. Metagenomic libraries from brine and rhizosphere samples, were transferred to the osmosensitive strain E. coli MKH13, and screened for salt resistance. Eleven genes that conferred salt resistance were identified, some encoding for well-known proteins previously related to osmoadaptation such as a glycerol transporter and a proton pump, whereas others encoded proteins not previously related to this function in microorganisms such as DNA/RNA helicases, an endonuclease III (Nth) and hypothetical proteins of unknown function. Furthermore, four of the retrieved genes were cloned and expressed in Bacillus subtilis and they also conferred salt resistance to this bacterium, broadening the spectrum of bacterial species in which these genes can function. This is the first report of salt resistance genes recovered from metagenomes of a hypersaline environment.
Collapse
Affiliation(s)
- Salvador Mirete
- Laboratory of Molecular Adaptation, Department of Molecular Evolution, Centro de Astrobiología, Consejo Superior de Investigaciones Científicas - Instituto Nacional de Técnica Aeroespacial, Madrid Spain
| | - Merit R Mora-Ruiz
- Marine Microbiology Group, Department of Ecology and Marine Resources, Mediterranean Institute for Advanced Studies, Consejo Superior de Investigaciones Científicas - Universidad de las Islas Baleares, Esporles Spain
| | - María Lamprecht-Grandío
- Laboratory of Molecular Adaptation, Department of Molecular Evolution, Centro de Astrobiología, Consejo Superior de Investigaciones Científicas - Instituto Nacional de Técnica Aeroespacial, Madrid Spain
| | - Carolina G de Figueras
- Laboratory of Molecular Adaptation, Department of Molecular Evolution, Centro de Astrobiología, Consejo Superior de Investigaciones Científicas - Instituto Nacional de Técnica Aeroespacial, Madrid Spain
| | - Ramon Rosselló-Móra
- Marine Microbiology Group, Department of Ecology and Marine Resources, Mediterranean Institute for Advanced Studies, Consejo Superior de Investigaciones Científicas - Universidad de las Islas Baleares, Esporles Spain
| | - José E González-Pastor
- Laboratory of Molecular Adaptation, Department of Molecular Evolution, Centro de Astrobiología, Consejo Superior de Investigaciones Científicas - Instituto Nacional de Técnica Aeroespacial, Madrid Spain
| |
Collapse
|
116
|
Rodrigo-Baños M, Garbayo I, Vílchez C, Bonete MJ, Martínez-Espinosa RM. Carotenoids from Haloarchaea and Their Potential in Biotechnology. Mar Drugs 2015; 13:5508-32. [PMID: 26308012 PMCID: PMC4584337 DOI: 10.3390/md13095508] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/02/2015] [Accepted: 08/10/2015] [Indexed: 12/02/2022] Open
Abstract
The production of pigments by halophilic archaea has been analysed during the last half a century. The main reasons that sustains this research are: (i) many haloarchaeal species possess high carotenoids production availability; (ii) downstream processes related to carotenoid isolation from haloarchaea is relatively quick, easy and cheap; (iii) carotenoids production by haloarchaea can be improved by genetic modification or even by modifying several cultivation aspects such as nutrition, growth pH, temperature, etc.; (iv) carotenoids are needed to support plant and animal life and human well-being; and (v) carotenoids are compounds highly demanded by pharmaceutical, cosmetic and food markets. Several studies about carotenoid production by haloarchaea have been reported so far, most of them focused on pigments isolation or carotenoids production under different culture conditions. However, the understanding of carotenoid metabolism, regulation, and roles of carotenoid derivatives in this group of extreme microorganisms remains mostly unrevealed. The uses of those haloarchaeal pigments have also been poorly explored. This work summarises what has been described so far about carotenoids production by haloarchaea and their potential uses in biotechnology and biomedicine. In particular, new scientific evidence of improved carotenoid production by one of the better known haloarchaeon (Haloferax mediterranei) is also discussed.
Collapse
Affiliation(s)
- Montserrat Rodrigo-Baños
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
| | - Inés Garbayo
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - Carlos Vílchez
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - María José Bonete
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
| | - Rosa María Martínez-Espinosa
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
| |
Collapse
|
117
|
Raddadi N, Cherif A, Daffonchio D, Neifar M, Fava F. Biotechnological applications of extremophiles, extremozymes and extremolytes. Appl Microbiol Biotechnol 2015; 99:7907-13. [PMID: 26272092 DOI: 10.1007/s00253-015-6874-9] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Revised: 07/20/2015] [Accepted: 07/22/2015] [Indexed: 11/24/2022]
Abstract
In the last decade, attention to extreme environments has increased because of interests to isolate previously unknown extremophilic microorganisms in pure culture and to profile their metabolites. Microorganisms that live in extreme environments produce extremozymes and extremolytes that have the potential to be valuable resources for the development of a bio-based economy through their application to white, red, and grey biotechnologies. Here, we provide an overview of extremophile ecology, and we review the most recent applications of microbial extremophiles and the extremozymes and extremolytes they produce to biotechnology.
Collapse
Affiliation(s)
- Noura Raddadi
- Department of Civil, Chemical, Environmental and Materials Engineering (DICAM), University of Bologna, via Terracini 28, 40131, Bologna, Italy,
| | | | | | | | | |
Collapse
|
118
|
DasSarma S, DasSarma P. Halophiles and their enzymes: negativity put to good use. Curr Opin Microbiol 2015; 25:120-6. [PMID: 26066288 PMCID: PMC4729366 DOI: 10.1016/j.mib.2015.05.009] [Citation(s) in RCA: 141] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 04/20/2015] [Accepted: 05/15/2015] [Indexed: 12/24/2022]
Abstract
Halophilic microorganisms possess stable enzymes that function in very high salinity, an extreme condition that leads to denaturation, aggregation, and precipitation of most other proteins. Genomic and structural analyses have established that the enzymes of halophilic Archaea and many halophilic Bacteria are negatively charged due to an excess of acidic over basic residues, and altered hydrophobicity, which enhance solubility and promote function in low water activity conditions. Here, we provide an update on recent bioinformatic analysis of predicted halophilic proteomes as well as experimental molecular studies on individual halophilic enzymes. Recent efforts on discovery and utilization of halophiles and their enzymes for biotechnology, including biofuel applications are also considered.
Collapse
Affiliation(s)
- Shiladitya DasSarma
- Institute of Marine and Environmental Technology, Department of Microbiology and Immunology, University of Maryland School of Medicine, 701 East Pratt Street, Columbus Center, Baltimore, MD 21202, USA.
| | - Priya DasSarma
- Institute of Marine and Environmental Technology, Department of Microbiology and Immunology, University of Maryland School of Medicine, 701 East Pratt Street, Columbus Center, Baltimore, MD 21202, USA
| |
Collapse
|
119
|
Papke RT, Corral P, Ram-Mohan N, de la Haba RR, Sánchez-Porro C, Makkay A, Ventosa A. Horizontal gene transfer, dispersal and haloarchaeal speciation. Life (Basel) 2015; 5:1405-26. [PMID: 25997110 PMCID: PMC4500145 DOI: 10.3390/life5021405] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 05/08/2015] [Accepted: 05/11/2015] [Indexed: 11/28/2022] Open
Abstract
The Halobacteria are a well-studied archaeal class and numerous investigations are showing how their diversity is distributed amongst genomes and geographic locations. Evidence indicates that recombination between species continuously facilitates the arrival of new genes, and within species, it is frequent enough to spread acquired genes amongst all individuals in the population. To create permanent independent diversity and generate new species, barriers to recombination are probably required. The data support an interpretation that rates of evolution (e.g., horizontal gene transfer and mutation) are faster at creating geographically localized variation than dispersal and invasion are at homogenizing genetic differences between locations. Therefore, we suggest that recurrent episodes of dispersal followed by variable periods of endemism break the homogenizing forces of intrapopulation recombination and that this process might be the principal stimulus leading to divergence and speciation in Halobacteria.
Collapse
Affiliation(s)
- R. Thane Papke
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, USA; E-Mails: (N.R.-M.); (A.M.)
- Author to whom correspondence should be addressed; E-Mail:
| | - Paulina Corral
- Department of Microbiology and Parasitology, University of Seville, 41004 Seville, Spain; E-Mails: (P.C.); (R.R.H.); (C.S.-P.); (A.V.)
| | - Nikhil Ram-Mohan
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, USA; E-Mails: (N.R.-M.); (A.M.)
| | - Rafael R. de la Haba
- Department of Microbiology and Parasitology, University of Seville, 41004 Seville, Spain; E-Mails: (P.C.); (R.R.H.); (C.S.-P.); (A.V.)
| | - Cristina Sánchez-Porro
- Department of Microbiology and Parasitology, University of Seville, 41004 Seville, Spain; E-Mails: (P.C.); (R.R.H.); (C.S.-P.); (A.V.)
| | - Andrea Makkay
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, USA; E-Mails: (N.R.-M.); (A.M.)
| | - Antonio Ventosa
- Department of Microbiology and Parasitology, University of Seville, 41004 Seville, Spain; E-Mails: (P.C.); (R.R.H.); (C.S.-P.); (A.V.)
| |
Collapse
|
120
|
Papke RT. Preface to the proceedings of Halophiles 2013. Front Microbiol 2015; 6:341. [PMID: 25954264 PMCID: PMC4406061 DOI: 10.3389/fmicb.2015.00341] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 04/07/2015] [Indexed: 12/14/2022] Open
Affiliation(s)
- R Thane Papke
- Department of Molecular and Cell Biology, University of Connecticut Storrs, CT, USA
| |
Collapse
|
121
|
Structural changes in halophilic and non-halophilic proteases in response to chaotropic reagents. Protein J 2015; 33:394-402. [PMID: 25008068 DOI: 10.1007/s10930-014-9571-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Halophilic enzymes have been established for their stability and catalytic abilities under harsh operational conditions. These have been documented to withstand denaturation at high temperature, pH, organic solvents, and chaotropic agents. However, this stability is modulated by salt. The present study targets an important aspect in understanding protein-urea/GdmCl interactions using proteases from halophilic Bacillus sp. EMB9 and non-halophilic subtilisin (Carlsberg) from Bacillus licheniformis as model systems. While, halophilic protease containing 1 % (w/v) NaCl (0.17 M) retained full activity towards urea (8 M), non-halophilic protease lost about 90 % activity under similar conditions. The secondary and tertiary structure were lost in non-halophilic but preserved for halophilic protein. This effect could be due to the possible charge screening and shielding of the protein surface by Ca(2+) and Na(+) ions rendering it stable against denaturation. The dialyzed halophilic protease almost behaved like the non-halophilic counterpart. Incorporation of NaCl (up to 5 %, w/v or 0.85 M) in dialyzed EMB9 protease containing urea/GdmCl, not only helped regain of proteolytic activity but also evaded denaturing action. Deciphering the basis of this salt modulated stability amidst a denaturing milieu will provide guidelines and templates for engineering stable proteins/enzymes for biotechnological applications.
Collapse
|
122
|
Kamanda Ngugi D, Blom J, Alam I, Rashid M, Ba-Alawi W, Zhang G, Hikmawan T, Guan Y, Antunes A, Siam R, El Dorry H, Bajic V, Stingl U. Comparative genomics reveals adaptations of a halotolerant thaumarchaeon in the interfaces of brine pools in the Red Sea. THE ISME JOURNAL 2015; 9:396-411. [PMID: 25105904 PMCID: PMC4303633 DOI: 10.1038/ismej.2014.137] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 05/29/2014] [Accepted: 06/21/2014] [Indexed: 02/05/2023]
Abstract
The bottom of the Red Sea harbors over 25 deep hypersaline anoxic basins that are geochemically distinct and characterized by vertical gradients of extreme physicochemical conditions. Because of strong changes in density, particulate and microbial debris get entrapped in the brine-seawater interface (BSI), resulting in increased dissolved organic carbon, reduced dissolved oxygen toward the brines and enhanced microbial activities in the BSI. These features coupled with the deep-sea prevalence of ammonia-oxidizing archaea (AOA) in the global ocean make the BSI a suitable environment for studying the osmotic adaptations and ecology of these important players in the marine nitrogen cycle. Using phylogenomic-based approaches, we show that the local archaeal community of five different BSI habitats (with up to 18.2% salinity) is composed mostly of a single, highly abundant Nitrosopumilus-like phylotype that is phylogenetically distinct from the bathypelagic thaumarchaea; ammonia-oxidizing bacteria were absent. The composite genome of this novel Nitrosopumilus-like subpopulation (RSA3) co-assembled from multiple single-cell amplified genomes (SAGs) from one such BSI habitat further revealed that it shares ∼54% of its predicted genomic inventory with sequenced Nitrosopumilus species. RSA3 also carries several, albeit variable gene sets that further illuminate the phylogenetic diversity and metabolic plasticity of this genus. Specifically, it encodes for a putative proline-glutamate 'switch' with a potential role in osmotolerance and indirect impact on carbon and energy flows. Metagenomic fragment recruitment analyses against the composite RSA3 genome, Nitrosopumilus maritimus, and SAGs of mesopelagic thaumarchaea also reiterate the divergence of the BSI genotypes from other AOA.
Collapse
Affiliation(s)
- David Kamanda Ngugi
- Red Sea Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus Liebig University, Giessen, Germany
| | - Intikhab Alam
- Computational Bioscience Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Mamoon Rashid
- Red Sea Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Wail Ba-Alawi
- Computational Bioscience Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Guishan Zhang
- Red Sea Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Tyas Hikmawan
- Red Sea Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Yue Guan
- Red Sea Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Andre Antunes
- Red Sea Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Rania Siam
- Department of Biology, American University in Cairo, Cairo, Egypt
| | - Hamza El Dorry
- Department of Biology, American University in Cairo, Cairo, Egypt
| | - Vladimir Bajic
- Computational Bioscience Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Ulrich Stingl
- Red Sea Research Centre, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| |
Collapse
|
123
|
Lievens B, Hallsworth JE, Pozo MI, Belgacem ZB, Stevenson A, Willems KA, Jacquemyn H. Microbiology of sugar-rich environments: diversity, ecology and system constraints. Environ Microbiol 2014; 17:278-98. [PMID: 25041632 DOI: 10.1111/1462-2920.12570] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2014] [Revised: 07/04/2014] [Accepted: 07/12/2014] [Indexed: 12/18/2022]
Abstract
Microbial habitats that contain an excess of carbohydrate in the form of sugar are widespread in the microbial biosphere. Depending on the type of sugar, prevailing water activity and other substances present, sugar-rich environments can be highly dynamic or relatively stable, osmotically stressful, and/or destabilizing for macromolecular systems, and can thereby strongly impact the microbial ecology. Here, we review the microbiology of different high-sugar habitats, including their microbial diversity and physicochemical parameters, which act to impact microbial community assembly and constrain the ecosystem. Saturated sugar beet juice and floral nectar are used as case studies to explore the differences between the microbial ecologies of low and higher water-activity habitats respectively. Nectar is a paradigm of an open, dynamic and biodiverse habitat populated by many microbial taxa, often yeasts and bacteria such as, amongst many others, Metschnikowia spp. and Acinetobacter spp., respectively. By contrast, thick juice is a relatively stable, species-poor habitat and is typically dominated by a single, xerotolerant bacterium (Tetragenococcus halophilus). A number of high-sugar habitats contain chaotropic solutes (e.g. ethyl acetate, phenols, ethanol, fructose and glycerol) and hydrophobic stressors (e.g. ethyl octanoate, hexane, octanol and isoamyl acetate), all of which can induce chaotropicity-mediated stresses that inhibit or prevent multiplication of microbes. Additionally, temperature, pH, nutrition, microbial dispersion and habitat history can determine or constrain the microbiology of high-sugar milieux. Findings are discussed in relation to a number of unanswered scientific questions.
Collapse
Affiliation(s)
- Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM), Department of Microbial and Molecular Systems (M2S), KU Leuven, B-2860, Sint-Katelijne-Waver, Belgium
| | | | | | | | | | | | | |
Collapse
|
124
|
Sorokin DY, Berben T, Melton ED, Overmars L, Vavourakis CD, Muyzer G. Microbial diversity and biogeochemical cycling in soda lakes. Extremophiles 2014; 18:791-809. [PMID: 25156418 PMCID: PMC4158274 DOI: 10.1007/s00792-014-0670-9] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 06/26/2014] [Indexed: 01/26/2023]
Abstract
Soda lakes contain high concentrations of sodium carbonates resulting in a stable elevated pH, which provide a unique habitat to a rich diversity of haloalkaliphilic bacteria and archaea. Both cultivation-dependent and -independent methods have aided the identification of key processes and genes in the microbially mediated carbon, nitrogen, and sulfur biogeochemical cycles in soda lakes. In order to survive in this extreme environment, haloalkaliphiles have developed various bioenergetic and structural adaptations to maintain pH homeostasis and intracellular osmotic pressure. The cultivation of a handful of strains has led to the isolation of a number of extremozymes, which allow the cell to perform enzymatic reactions at these extreme conditions. These enzymes potentially contribute to biotechnological applications. In addition, microbial species active in the sulfur cycle can be used for sulfur remediation purposes. Future research should combine both innovative culture methods and state-of-the-art 'meta-omic' techniques to gain a comprehensive understanding of the microbes that flourish in these extreme environments and the processes they mediate. Coupling the biogeochemical C, N, and S cycles and identifying where each process takes place on a spatial and temporal scale could unravel the interspecies relationships and thereby reveal more about the ecosystem dynamics of these enigmatic extreme environments.
Collapse
Affiliation(s)
- Dimitry Y. Sorokin
- Winogradsky Institute of Microbiology, RAS, Moscow, Russia
- Department of Biotechnology, Delft University of Technology, Delft, The Netherlands
| | - Tom Berben
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Emily Denise Melton
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Lex Overmars
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Charlotte D. Vavourakis
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Gerard Muyzer
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| |
Collapse
|
125
|
León MJ, Fernández AB, Ghai R, Sánchez-Porro C, Rodriguez-Valera F, Ventosa A. From metagenomics to pure culture: isolation and characterization of the moderately halophilic bacterium Spiribacter salinus gen. nov., sp. nov. Appl Environ Microbiol 2014; 80:3850-7. [PMID: 24747894 PMCID: PMC4054224 DOI: 10.1128/aem.00430-14] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Accepted: 04/12/2014] [Indexed: 11/20/2022] Open
Abstract
Recent metagenomic studies on saltern ponds with intermediate salinities have determined that their microbial communities are dominated by both Euryarchaeota and halophilic bacteria, with a gammaproteobacterium closely related to the genera Alkalilimnicola and Arhodomonas being one of the most predominant microorganisms, making up to 15% of the total prokaryotic population. Here we used several strategies and culture media in order to isolate this organism in pure culture. We report the isolation and taxonomic characterization of this new, never before cultured microorganism, designated M19-40(T), isolated from a saltern located in Isla Cristina, Spain, using a medium with a mixture of 15% salts, yeast extract, and pyruvic acid as the carbon source. Morphologically small curved cells (young cultures) with a tendency to form long spiral cells in older cultures were observed in pure cultures. The organism is a Gram-negative, nonmotile bacterium that is strictly aerobic, non-endospore forming, heterotrophic, and moderately halophilic, and it is able to grow at 10 to 25% (wt/vol) NaCl, with optimal growth occurring at 15% (wt/vol) NaCl. Phylogenetic analysis based on 16S rRNA gene sequence comparison showed that strain M19-40(T) has a low similarity with other previously described bacteria and shows the closest phylogenetic similarity with species of the genera Alkalilimnicola (94.9 to 94.5%), Alkalispirillum (94.3%), and Arhodomonas (93.9%) within the family Ectothiorhodospiraceae. The phenotypic, genotypic, and chemotaxonomic features of this new bacterium showed that it constitutes a new genus and species, for which the name Spiribacter salinus gen. nov., sp. nov., is proposed, with strain M19-40(T) (= CECT 8282(T) = IBRC-M 10768(T) = LMG 27464(T)) being the type strain.
Collapse
Affiliation(s)
- María José León
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, Seville, Spain
| | - Ana B Fernández
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, Seville, Spain
| | - Rohit Ghai
- Evolutionary Genomics Group, Division of Microbiology, Miguel Hernández University, San Juan, Alicante, Spain
| | - Cristina Sánchez-Porro
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, Seville, Spain
| | - Francisco Rodriguez-Valera
- Evolutionary Genomics Group, Division of Microbiology, Miguel Hernández University, San Juan, Alicante, Spain
| | - Antonio Ventosa
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Seville, Seville, Spain
| |
Collapse
|
126
|
Fernández AB, Vera-Gargallo B, Sánchez-Porro C, Ghai R, Papke RT, Rodriguez-Valera F, Ventosa A. Comparison of prokaryotic community structure from Mediterranean and Atlantic saltern concentrator ponds by a metagenomic approach. Front Microbiol 2014; 5:196. [PMID: 24847316 PMCID: PMC4021199 DOI: 10.3389/fmicb.2014.00196] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Accepted: 04/12/2014] [Indexed: 12/02/2022] Open
Abstract
We analyzed the prokaryotic community structure of a saltern pond with 21% total salts located in Isla Cristina, Huelva, Southwest Spain, close to the Atlantic ocean coast. For this purpose, we constructed a metagenome (designated as IC21) obtained by pyrosequencing consisting of 486 Mb with an average read length of 397 bp and compared it with other metagenomic datasets obtained from ponds with 19, 33, and 37% total salts acquired from Santa Pola marine saltern, located in Alicante, East Spain, on the Mediterranean coast. Although the salinity in IC21 is closer to the pond with 19% total salts from Santa Pola saltern (designated as SS19), IC21 is more similar at higher taxonomic levels to the pond with 33% total salts from Santa Pola saltern (designated as SS33), since both are predominated by the phylum Euryarchaeota. However, there are significant differences at lower taxonomic levels where most sequences were related to the genus Halorubrum in IC21 and to Haloquadratum in SS33. Within the Bacteroidetes, the genus Psychroflexus is the most abundant in IC21 while Salinibacter dominates in SS33. Sequences related to bacteriorhodopsins and halorhodopsins correlate with the abundance of Haloquadratum in Santa Pola SS19 to SS33 and of Halorubrum in Isla Cristina IC21 dataset, respectively. Differences in composition might be attributed to local ecological conditions since IC21 showed a decrease in the number of sequences related to the synthesis of compatible solutes and in the utilization of phosphonate.
Collapse
Affiliation(s)
- Ana B Fernández
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla Sevilla, Spain
| | - Blanca Vera-Gargallo
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla Sevilla, Spain
| | - Cristina Sánchez-Porro
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla Sevilla, Spain
| | - Rohit Ghai
- Evolutionary Genomics Group, Departamento de Producción Vegetal y Microbiología, Universidad Miguel Hernández, San Juan de Alicante Alicante, Spain
| | - R Thane Papke
- Department of Molecular and Cell Biology, University of Connecticut Storrs, CT, USA
| | - Francisco Rodriguez-Valera
- Evolutionary Genomics Group, Departamento de Producción Vegetal y Microbiología, Universidad Miguel Hernández, San Juan de Alicante Alicante, Spain
| | - Antonio Ventosa
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla Sevilla, Spain
| |
Collapse
|
127
|
Fernández AB, Ghai R, Martin-Cuadrado AB, Sánchez-Porro C, Rodriguez-Valera F, Ventosa A. Prokaryotic taxonomic and metabolic diversity of an intermediate salinity hypersaline habitat assessed by metagenomics. FEMS Microbiol Ecol 2014; 88:623-35. [PMID: 24661078 DOI: 10.1111/1574-6941.12329] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 03/11/2014] [Accepted: 03/12/2014] [Indexed: 11/28/2022] Open
Abstract
A metagenome was obtained by pyrosequencing the total prokaryotic DNA from the water of a pond with intermediate salinity (13% salts) from a saltern located in Santa Pola, Spain. We analyzed and compared the phylogenomic and metabolic diversity of this saltern pond with respect to other two metagenomes obtained previously from the same saltern (ponds with 19% and 37% salts, respectively) and two reference metagenomes from marine and coastal lagoon habitats. A large microbial diversity, representing seven major higher taxa (Euryarchaeota, Gammaproteobacteria, Alphaproteobacteria, Actinobacteria, Bacteroidetes, Verrucomicrobia and Betaproteobacteria), was found. However, most sequences (57%) were not assigned to any previously described genus. Principal component analysis of tetranucleotide frequencies of assembled contigs showed the presence of new groups of Euryarchaeota, different from those previously described but related to Haloquadratum walsbyi and other members of the Halobacteriaceae. Besides, some new Gammaproteobacteria, several closely related to the recently isolated bacterium 'Spiribacter salinus' were observed. Metabolically, the nitrogen and carbon cycles appear to be very simplified in this extreme habitat. Light is extensively used as energy source by bacteriorhodopsins and other rhodopsins. Microorganisms known to use the 'salt-in' strategy are probably able to combine the accumulation of potassium ions and of compatible solutes.
Collapse
Affiliation(s)
- Ana B Fernández
- Department of Microbiology and Parasitology, Faculty of Pharmacy, University of Sevilla, Sevilla, Spain
| | | | | | | | | | | |
Collapse
|
128
|
Sinha R, Khare SK. Protective role of salt in catalysis and maintaining structure of halophilic proteins against denaturation. Front Microbiol 2014; 5:165. [PMID: 24782853 PMCID: PMC3988381 DOI: 10.3389/fmicb.2014.00165] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 03/27/2014] [Indexed: 11/23/2022] Open
Abstract
Search for new industrial enzymes having novel properties continues to be a desirable pursuit in enzyme research. The halophilic organisms inhabiting under saline/ hypersaline conditions are considered as promising source of useful enzymes. Their enzymes are structurally adapted to perform efficient catalysis under saline environment wherein n0n-halophilic enzymes often lose their structure and activity. Haloenzymes have been documented to be polyextremophilic and withstand high temperature, pH, organic solvents, and chaotropic agents. However, this stability is modulated by salt. Although vast amount of information have been generated on salt mediated protection and structure function relationship in halophilic proteins, their clear understanding and correct perspective still remain incoherent. Furthermore, understanding their protein architecture may give better clue for engineering stable enzymes which can withstand harsh industrial conditions. The article encompasses the current level of understanding about haloadaptations and analyzes structural basis of their enzyme stability against classical denaturants.
Collapse
Affiliation(s)
- Rajeshwari Sinha
- Department of Chemistry, Indian Institute of Technology Delhi Delhi, India
| | - Sunil K Khare
- Department of Chemistry, Indian Institute of Technology Delhi Delhi, India
| |
Collapse
|
129
|
Talon R, Coquelle N, Madern D, Girard E. An experimental point of view on hydration/solvation in halophilic proteins. Front Microbiol 2014; 5:66. [PMID: 24600446 PMCID: PMC3930881 DOI: 10.3389/fmicb.2014.00066] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Accepted: 02/04/2014] [Indexed: 11/23/2022] Open
Abstract
Protein-solvent interactions govern the behaviors of proteins isolated from extreme halophiles. In this work, we compared the solvent envelopes of two orthologous tetrameric malate dehydrogenases (MalDHs) from halophilic and non-halophilic bacteria. The crystal structure of the MalDH from the non-halophilic bacterium Chloroflexus aurantiacus (Ca MalDH) solved, de novo, at 1.7 Å resolution exhibits numerous water molecules in its solvation shell. We observed that a large number of these water molecules are arranged in pentagonal polygons in the first hydration shell of Ca MalDH. Some of them are clustered in large networks, which cover non-polar amino acid surface. The crystal structure of MalDH from the extreme halophilic bacterium Salinibacter ruber (Sr) solved at 1.55 Å resolution shows that its surface is strongly enriched in acidic amino acids. The structural comparison of these two models is the first direct observation of the relative impact of acidic surface enrichment on the water structure organization between a halophilic protein and its non-adapted counterpart. The data show that surface acidic amino acids disrupt pentagonal water networks in the hydration shell. These crystallographic observations are discussed with respect to halophilic protein behaviors in solution
Collapse
Affiliation(s)
- Romain Talon
- Institut de Biologie Structurale, Université Grenoble Alpes Grenoble, France ; CEA, DSV, Institut de Biologie Structurale Grenoble, France ; Institut de Biologie Structurale, Centre National de la Recherche Scientifique Grenoble, France
| | - Nicolas Coquelle
- Institut de Biologie Structurale, Université Grenoble Alpes Grenoble, France ; CEA, DSV, Institut de Biologie Structurale Grenoble, France ; Institut de Biologie Structurale, Centre National de la Recherche Scientifique Grenoble, France
| | - Dominique Madern
- Institut de Biologie Structurale, Université Grenoble Alpes Grenoble, France ; CEA, DSV, Institut de Biologie Structurale Grenoble, France ; Institut de Biologie Structurale, Centre National de la Recherche Scientifique Grenoble, France
| | - Eric Girard
- Institut de Biologie Structurale, Université Grenoble Alpes Grenoble, France ; CEA, DSV, Institut de Biologie Structurale Grenoble, France ; Institut de Biologie Structurale, Centre National de la Recherche Scientifique Grenoble, France
| |
Collapse
|