1
|
Liew KJ, Shahar S, Shamsir MS, Shaharuddin NB, Liang CH, Chan KG, Pointing SB, Sani RK, Goh KM. Integrating multi-platform assembly to recover MAGs from hot spring biofilms: insights into microbial diversity, biofilm formation, and carbohydrate degradation. ENVIRONMENTAL MICROBIOME 2024; 19:29. [PMID: 38706006 PMCID: PMC11071339 DOI: 10.1186/s40793-024-00572-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 04/22/2024] [Indexed: 05/07/2024]
Abstract
BACKGROUND Hot spring biofilms provide a window into the survival strategies of microbial communities in extreme environments and offer potential for biotechnological applications. This study focused on green and brown biofilms thriving on submerged plant litter within the Sungai Klah hot spring in Malaysia, characterised by temperatures of 58-74 °C. Using Illumina shotgun metagenomics and Nanopore ligation sequencing, we investigated the microbial diversity and functional potential of metagenome-assembled genomes (MAGs) with specific focus on biofilm formation, heat stress response, and carbohydrate catabolism. RESULTS Leveraging the power of both Illumina short-reads and Nanopore long-reads, we employed an Illumina-Nanopore hybrid assembly approach to construct MAGs with enhanced quality. The dereplication process, facilitated by the dRep tool, validated the efficiency of the hybrid assembly, yielding MAGs that reflected the intricate microbial diversity of these extreme ecosystems. The comprehensive analysis of these MAGs uncovered intriguing insights into the survival strategies of thermophilic taxa in the hot spring biofilms. Moreover, we examined the plant litter degradation potential within the biofilms, shedding light on the participation of diverse microbial taxa in the breakdown of starch, cellulose, and hemicellulose. We highlight that Chloroflexota and Armatimonadota MAGs exhibited a wide array of glycosyl hydrolases targeting various carbohydrate substrates, underscoring their metabolic versatility in utilisation of carbohydrates at elevated temperatures. CONCLUSIONS This study advances understanding of microbial ecology on plant litter under elevated temperature by revealing the functional adaptation of MAGs from hot spring biofilms. In addition, our findings highlight potential for biotechnology application through identification of thermophilic lignocellulose-degrading enzymes. By demonstrating the efficiency of hybrid assembly utilising Illumina-Nanopore reads, we highlight the value of combining multiple sequencing methods for a more thorough exploration of complex microbial communities.
Collapse
Grants
- FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4 Malaysia Fundamental Research Grant Scheme (FRGS)
- FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4 Malaysia Fundamental Research Grant Scheme (FRGS)
- FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4 Malaysia Fundamental Research Grant Scheme (FRGS)
- FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4 Malaysia Fundamental Research Grant Scheme (FRGS)
- FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4 Malaysia Fundamental Research Grant Scheme (FRGS)
- 4J549 UTM QuickWin grant
- 4J549 UTM QuickWin grant
- T2EP30123-0028 Singapore Ministry of Education ARC Tier 2 fund
- 1736255, 1849206, and 1920954 National Science Foundation
Collapse
Affiliation(s)
- Kok Jun Liew
- Codon Genomics, 42300 Seri Kembangan, Selangor, Malaysia
| | - Saleha Shahar
- Faculty of Science, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
| | - Mohd Shahir Shamsir
- Faculty of Science, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
| | - Nawal Binti Shaharuddin
- School of Professional and Continuing Education, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
| | - Chee Hung Liang
- Faculty of Science, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia
| | - Kok-Gan Chan
- Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Stephen Brian Pointing
- Department of Biological Sciences, National University of Singapore, Singapore, Singapore
| | - Rajesh Kumar Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology, Rapid City, SD, 57701, USA.
| | - Kian Mau Goh
- Faculty of Science, Universiti Teknologi Malaysia, 81310, Skudai, Johor, Malaysia.
| |
Collapse
|
2
|
Dedysh SN. Describing difficult-to-culture bacteria: Taking a shortcut or investing time to discover something new? Syst Appl Microbiol 2023; 46:126439. [PMID: 37413783 DOI: 10.1016/j.syapm.2023.126439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 06/17/2023] [Accepted: 06/29/2023] [Indexed: 07/08/2023]
Abstract
Despite the growing interest in isolating representatives of poorly studied and as-yet-uncultivated bacterial phylogenetic groups, these microorganisms remain difficult objects for taxonomic studies. The time required for describing one of these fastidious bacteria is commonly measured in several years. What is even more problematic, many routine laboratory tests, which were originally developed for fast-growing and fast-responding microorganisms, are not fully suitable for many environmentally relevant, slow-growing bacteria. Standard techniques used in chemotaxonomic analyses do not identify unique lipids produced by these bacteria. A common practice of preparing taxonomic descriptions that report a minimal set of features to name a newly isolated organism deepens a gap between microbial ecologists and taxonomists. By contrast, investing time in detailed analysis of cell biology and experimental verification of genome-encoded capabilities of newly isolated microorganisms opens a window for novel, unexpected findings, which may shape our ideas about the functional role of these microbes in the environment.
Collapse
Affiliation(s)
- Svetlana N Dedysh
- Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia.
| |
Collapse
|
3
|
Structure of the Acidobacteria homodimeric reaction center bound with cytochrome c. Nat Commun 2022; 13:7745. [PMID: 36517472 PMCID: PMC9751088 DOI: 10.1038/s41467-022-35460-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 12/02/2022] [Indexed: 12/23/2022] Open
Abstract
Photosynthesis converts light energy to chemical energy to fuel life on earth. Light energy is harvested by antenna pigments and transferred to reaction centers (RCs) to drive the electron transfer (ET) reactions. Here, we present cryo-electron microscopy (cryo-EM) structures of two forms of the RC from the microaerophilic Chloracidobacterium thermophilum (CabRC): one containing 10 subunits, including two different cytochromes; and the other possessing two additional subunits, PscB and PscZ. The larger form contained 2 Zn-bacteriochlorophylls, 16 bacteriochlorophylls, 10 chlorophylls, 2 lycopenes, 2 hemes, 3 Fe4S4 clusters, 12 lipids, 2 Ca2+ ions and 6 water molecules, revealing a type I RC with an ET chain involving two hemes and a hybrid antenna containing bacteriochlorophylls and chlorophylls. Our results provide a structural basis for understanding the excitation energy and ET within the CabRC and offer evolutionary insights into the origin and adaptation of photosynthetic RCs.
Collapse
|
4
|
Microbial Communities of Ferromanganese Sedimentary Layers and Nodules of Lake Baikal (Bolshoy Ushkany Island). DIVERSITY 2022. [DOI: 10.3390/d14100868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Ferromanganese (Fe-Mn) sedimentary layers and nodules occur at different depths within sediments at deep basins and ridges of Lake Baikal. We studied Fe-Mn nodules and host sediments recovered at the slope of Bolshoy Ushkany Island. Layer-by-layer 230Th/U dating analysis determined the initial age of the Fe-Mn nodule formation scattered in the sediments as 96 ± 5–131 ± 8 Ka. The distribution profiles of the main ions in the pore waters of the studied sediment are similar to those observed in the deep-sea areas of Lake Baikal, while the chemical composition of Fe-Mn nodules indicates their diagenetic formation with hydrothermal influence. Among the bacteria in microbial communities of sediments, members of organoheterotrophic Gammaproteobacteria, Chloroflexi, Actinobacteriota, Acidobacteriota, among them Archaea—chemolithoautotrophic ammonia-oxidizing archaea Nitrososphaeria, dominated. About 13% of the bacterial 16S rRNA gene sequences in Fe-Mn layers belonged to Methylomirabilota representatives which use nitrite ions as electron acceptors for the anaerobic oxidation of methane (AOM). Nitrospirota comprised up to 9% of the layers of Bolshoy Ushkany Island. In bacterial communities of Fe-Mn nodule, a large percentage of sequences were attributed to Alphaproteobacteria, Actinobacteriota and Firmicutes, as well as a variety of OTUs with a small number of sequences characteristic of hydrothermal ecosystems. The contribution of representatives of Methylomirabilota and Nitrospirota in communities of Fe-Mn nodule was minor. Our data support the hypothesis that chemolithoautotrophs associated with ammonium-oxidizing archaea and nitrite-oxidizing bacteria can potentially play an important role as primary producers of Fe-Mn substrates in freshwater Lake Baikal.
Collapse
|
5
|
Ruhl IA, Sheremet A, Furgason CC, Krause S, Bowers RM, Jarett JK, Tran TM, Grasby SE, Woyke T, Dunfield PF. GAL08, an Uncultivated Group of Acidobacteria, Is a Dominant Bacterial Clade in a Neutral Hot Spring. Front Microbiol 2022; 12:787651. [PMID: 35087491 PMCID: PMC8787282 DOI: 10.3389/fmicb.2021.787651] [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: 10/01/2021] [Accepted: 11/29/2021] [Indexed: 11/28/2022] Open
Abstract
GAL08 are bacteria belonging to an uncultivated phylogenetic cluster within the phylum Acidobacteria. We detected a natural population of the GAL08 clade in sediment from a pH-neutral hot spring located in British Columbia, Canada. To shed light on the abundance and genomic potential of this clade, we collected and analyzed hot spring sediment samples over a temperature range of 24.2–79.8°C. Illumina sequencing of 16S rRNA gene amplicons and qPCR using a primer set developed specifically to detect the GAL08 16S rRNA gene revealed that absolute and relative abundances of GAL08 peaked at 65°C along three temperature gradients. Analysis of sediment collected over multiple years and locations revealed that the GAL08 group was consistently a dominant clade, comprising up to 29.2% of the microbial community based on relative read abundance and up to 4.7 × 105 16S rRNA gene copy numbers per gram of sediment based on qPCR. Using a medium quality threshold, 25 single amplified genomes (SAGs) representing these bacteria were generated from samples taken at 65 and 77°C, and seven metagenome-assembled genomes (MAGs) were reconstructed from samples collected at 45–77°C. Based on average nucleotide identity (ANI), these SAGs and MAGs represented three separate species, with an estimated average genome size of 3.17 Mb and GC content of 62.8%. Phylogenetic trees constructed from 16S rRNA gene sequences and a set of 56 concatenated phylogenetic marker genes both placed the three GAL08 bacteria as a distinct subgroup of the phylum Acidobacteria, representing a candidate order (Ca. Frugalibacteriales) within the class Blastocatellia. Metabolic reconstructions from genome data predicted a heterotrophic metabolism, with potential capability for aerobic respiration, as well as incomplete denitrification and fermentation. In laboratory cultivation efforts, GAL08 counts based on qPCR declined rapidly under atmospheric levels of oxygen but increased slightly at 1% (v/v) O2, suggesting a microaerophilic lifestyle.
Collapse
Affiliation(s)
- Ilona A Ruhl
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Andriy Sheremet
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Chantel C Furgason
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Susanne Krause
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Robert M Bowers
- U.S. Department of Energy Joint Genome Institute, Berkeley, CA, United States
| | - Jessica K Jarett
- U.S. Department of Energy Joint Genome Institute, Berkeley, CA, United States
| | - Triet M Tran
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Stephen E Grasby
- Department of Geoscience, University of Calgary, Calgary, AB, Canada.,Geological Survey of Canada, Calgary, AB, Canada
| | - Tanja Woyke
- U.S. Department of Energy Joint Genome Institute, Berkeley, CA, United States
| | - Peter F Dunfield
- Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| |
Collapse
|
6
|
Flieder M, Buongiorno J, Herbold CW, Hausmann B, Rattei T, Lloyd KG, Loy A, Wasmund K. Novel taxa of Acidobacteriota implicated in seafloor sulfur cycling. THE ISME JOURNAL 2021; 15:3159-3180. [PMID: 33981000 PMCID: PMC8528874 DOI: 10.1038/s41396-021-00992-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 04/05/2021] [Accepted: 04/15/2021] [Indexed: 02/03/2023]
Abstract
Acidobacteriota are widespread and often abundant in marine sediments, yet their metabolic and ecological properties are poorly understood. Here, we examined metabolisms and distributions of Acidobacteriota in marine sediments of Svalbard by functional predictions from metagenome-assembled genomes (MAGs), amplicon sequencing of 16S rRNA and dissimilatory sulfite reductase (dsrB) genes and transcripts, and gene expression analyses of tetrathionate-amended microcosms. Acidobacteriota were the second most abundant dsrB-harboring (averaging 13%) phylum after Desulfobacterota in Svalbard sediments, and represented 4% of dsrB transcripts on average. Meta-analysis of dsrAB datasets also showed Acidobacteriota dsrAB sequences are prominent in marine sediments worldwide, averaging 15% of all sequences analysed, and represent most of the previously unclassified dsrAB in marine sediments. We propose two new Acidobacteriota genera, Candidatus Sulfomarinibacter (class Thermoanaerobaculia, "subdivision 23") and Ca. Polarisedimenticola ("subdivision 22"), with distinct genetic properties that may explain their distributions in biogeochemically distinct sediments. Ca. Sulfomarinibacter encode flexible respiratory routes, with potential for oxygen, nitrous oxide, metal-oxide, tetrathionate, sulfur and sulfite/sulfate respiration, and possibly sulfur disproportionation. Potential nutrients and energy include cellulose, proteins, cyanophycin, hydrogen, and acetate. A Ca. Polarisedimenticola MAG encodes various enzymes to degrade proteins, and to reduce oxygen, nitrate, sulfur/polysulfide and metal-oxides. 16S rRNA gene and transcript profiling of Svalbard sediments showed Ca. Sulfomarinibacter members were relatively abundant and transcriptionally active in sulfidic fjord sediments, while Ca. Polarisedimenticola members were more relatively abundant in metal-rich fjord sediments. Overall, we reveal various physiological features of uncultured marine Acidobacteriota that indicate fundamental roles in seafloor biogeochemical cycling.
Collapse
Affiliation(s)
- Mathias Flieder
- grid.10420.370000 0001 2286 1424Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Joy Buongiorno
- grid.411461.70000 0001 2315 1184Department of Microbiology, University of Tennessee, Knoxville, TN USA ,grid.421147.50000 0000 8528 5498Present Address: Division of Natural Sciences, Maryville College, Maryville, TN USA
| | - Craig W. Herbold
- grid.10420.370000 0001 2286 1424Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Bela Hausmann
- grid.10420.370000 0001 2286 1424Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria ,grid.10420.370000 0001 2286 1424Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, Vienna, Austria ,grid.22937.3d0000 0000 9259 8492Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Thomas Rattei
- grid.10420.370000 0001 2286 1424Division of Computational Systems Biology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria
| | - Karen G. Lloyd
- grid.411461.70000 0001 2315 1184Department of Microbiology, University of Tennessee, Knoxville, TN USA
| | - Alexander Loy
- grid.10420.370000 0001 2286 1424Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria ,grid.10420.370000 0001 2286 1424Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, Vienna, Austria ,grid.465498.2Austrian Polar Research Institute, Vienna, Austria
| | - Kenneth Wasmund
- grid.10420.370000 0001 2286 1424Division of Microbial Ecology, Centre for Microbiology and Environmental Systems Science, University of Vienna, Vienna, Austria ,grid.465498.2Austrian Polar Research Institute, Vienna, Austria ,grid.5117.20000 0001 0742 471XCenter for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| |
Collapse
|
7
|
Yadav A, Borrelli JC, Elshahed MS, Youssef NH. Genomic Analysis of Family UBA6911 (Group 18 Acidobacteria) Expands the Metabolic Capacities of the Phylum and Highlights Adaptations to Terrestrial Habitats. Appl Environ Microbiol 2021; 87:e0094721. [PMID: 34160232 PMCID: PMC8357285 DOI: 10.1128/aem.00947-21] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 06/14/2021] [Indexed: 12/19/2022] Open
Abstract
Approaches for recovering and analyzing genomes belonging to novel, hitherto-unexplored bacterial lineages have provided invaluable insights into the metabolic capabilities and ecological roles of yet-uncultured taxa. The phylum Acidobacteria is one of the most prevalent and ecologically successful lineages on Earth, yet currently, multiple lineages within this phylum remain unexplored. Here, we utilize genomes recovered from Zodletone Spring, an anaerobic sulfide and sulfur-rich spring in southwestern Oklahoma, as well as from multiple disparate soil and nonsoil habitats, to examine the metabolic capabilities and ecological role of members of family UBA6911 (group 18) Acidobacteria. The analyzed genomes clustered into five distinct genera, with genera Gp18_AA60 and QHZH01 recovered from soils, genus Ga0209509 from anaerobic digestors, and genera Ga0212092 and UBA6911 from freshwater habitats. All genomes analyzed suggested that members of Acidobacteria group 18 are metabolically versatile heterotrophs capable of utilizing a wide range of proteins, amino acids, and sugars as carbon sources, possess respiratory and fermentative capacities, and display few auxotrophies. Soil-dwelling genera were characterized by larger genome sizes, higher numbers of CRISPR loci, an expanded carbohydrate active enzyme (CAZyme) machinery enabling debranching of specific sugars from polymers, possession of a C1 (methanol and methylamine) degradation machinery, and a sole dependence on aerobic respiration. In contrast, nonsoil genomes encoded a more versatile respiratory capacity for oxygen, nitrite, sulfate, and trimethylamine N-oxide (TMAO) respiration, as well as the potential for utilizing the Wood-Ljungdahl (WL) pathway as an electron sink during heterotrophic growth. Our results not only expand our knowledge of the metabolism of a yet-uncultured bacterial lineage but also provide interesting clues on how terrestrialization and niche adaptation drive metabolic specialization within the Acidobacteria. IMPORTANCE Members of the Acidobacteria are important players in global biogeochemical cycles, especially in soils. A wide range of acidobacterial lineages remain currently unexplored. We present a detailed genomic characterization of genomes belonging to family UBA6911 (also known as group 18) within the phylum Acidobacteria. The genomes belong to different genera and were obtained from soil (genera Gp18_AA60 and QHZH01), freshwater habitats (genera Ga0212092 and UBA6911), and an anaerobic digestor (genus Ga0209509). While all members of the family shared common metabolic features, e.g., heterotrophic respiratory abilities, broad substrate utilization capacities, and few auxotrophies, distinct differences between soil and nonsoil genera were observed. Soil genera were characterized by expanded genomes, higher numbers of CRISPR loci, a larger carbohydrate active enzyme (CAZyme) repertoire enabling monomer extractions from polymer side chains, and methylotrophic (methanol and methylamine) degradation capacities. In contrast, nonsoil genera encoded more versatile respiratory capacities for utilizing nitrite, sulfate, TMAO, and the WL pathway, in addition to oxygen as electron acceptors. Our results not only broaden our understanding of the metabolic capacities within the Acidobacteria but also provide interesting clues on how terrestrialization shaped Acidobacteria evolution and niche adaptation.
Collapse
Affiliation(s)
- Archana Yadav
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Jenna C. Borrelli
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Mostafa S. Elshahed
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Noha H. Youssef
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, Oklahoma, USA
| |
Collapse
|
8
|
Saini MK, Sebastian A, Shirotori Y, Soulier NT, Garcia Costas AM, Drautz-Moses DI, Schuster SC, Albert I, Haruta S, Hanada S, Thiel V, Tank M, Bryant DA. Genomic and Phenotypic Characterization of Chloracidobacterium Isolates Provides Evidence for Multiple Species. Front Microbiol 2021; 12:704168. [PMID: 34220789 PMCID: PMC8245765 DOI: 10.3389/fmicb.2021.704168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 05/21/2021] [Indexed: 11/16/2022] Open
Abstract
Chloracidobacterium is the first and until now the sole genus in the phylum Acidobacteriota (formerly Acidobacteria) whose members perform chlorophyll-dependent phototrophy (i.e., chlorophototrophy). An axenic isolate of Chloracidobacterium thermophilum (strain B T ) was previously obtained by using the inferred genome sequence from an enrichment culture and diel metatranscriptomic profiling analyses in situ to direct adjustments to the growth medium and incubation conditions, and thereby a defined growth medium for Chloracidobacterium thermophilum was developed. These advances allowed eight additional strains of Chloracidobacterium spp. to be isolated from microbial mat samples collected from Mushroom Spring, Yellowstone National Park, United States, at temperatures of 41, 52, and 60°C; an axenic strain was also isolated from Rupite hot spring in Bulgaria. All isolates are obligately photoheterotrophic, microaerophilic, non-motile, thermophilic, rod-shaped bacteria. Chloracidobacterium spp. synthesize multiple types of (bacterio-)chlorophylls and have type-1 reaction centers like those of green sulfur bacteria. Light harvesting is accomplished by the bacteriochlorophyll a-binding, Fenna-Matthews-Olson protein and chlorosomes containing bacteriochlorophyll c. Their genomes are approximately 3.7 Mbp in size and comprise two circular chromosomes with sizes of approximately 2.7 Mbp and 1.0 Mbp. Comparative genomic studies and phenotypic properties indicate that the nine isolates represent three species within the genus Chloracidobacterium. In addition to C. thermophilum, the microbial mats at Mushroom Spring contain a second species, tentatively named Chloracidobacterium aggregatum, which grows as aggregates in liquid cultures. The Bulgarian isolate, tentatively named Chloracidobacterium validum, will be proposed as the type species of the genus, Chloracidobacterium. Additionally, Chloracidobacterium will be proposed as the type genus of a new family, Chloracidobacteriaceae, within the order Blastocatellales, the class Blastocatellia, and the phylum Acidobacteriota.
Collapse
Affiliation(s)
- Mohit Kumar Saini
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Japan
| | - Aswathy Sebastian
- The Huck Institutes for the Life Sciences, The Pennsylvania State University, University Park, PA, United States
| | - Yoshiki Shirotori
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Japan
| | - Nathan T. Soulier
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States
| | - Amaya M. Garcia Costas
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States
- Department of Biology, Colorado State University-Pueblo, Pueblo, CO, United States
| | - Daniela I. Drautz-Moses
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Stephan C. Schuster
- Singapore Centre for Environmental Life Sciences Engineering, Nanyang Technological University, Singapore, Singapore
| | - Istvan Albert
- The Huck Institutes for the Life Sciences, The Pennsylvania State University, University Park, PA, United States
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States
| | - Shin Haruta
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Japan
| | - Satoshi Hanada
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Japan
| | - Vera Thiel
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Japan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States
- DSMZ – German Culture Collection of Microorganisms and Cell Cultures, GmbH, Braunschweig, Germany
| | - Marcus Tank
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Japan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States
- DSMZ – German Culture Collection of Microorganisms and Cell Cultures, GmbH, Braunschweig, Germany
| | - Donald A. Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, United States
| |
Collapse
|
9
|
Kalam S, Basu A, Ahmad I, Sayyed RZ, El-Enshasy HA, Dailin DJ, Suriani NL. Recent Understanding of Soil Acidobacteria and Their Ecological Significance: A Critical Review. Front Microbiol 2020; 11:580024. [PMID: 33193209 PMCID: PMC7661733 DOI: 10.3389/fmicb.2020.580024] [Citation(s) in RCA: 209] [Impact Index Per Article: 52.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 10/08/2020] [Indexed: 11/13/2022] Open
Abstract
Acidobacteria represents an underrepresented soil bacterial phylum whose members are pervasive and copiously distributed across nearly all ecosystems. Acidobacterial sequences are abundant in soils and represent a significant fraction of soil microbial community. Being recalcitrant and difficult-to-cultivate under laboratory conditions, holistic, polyphasic approaches are required to study these refractive bacteria extensively. Acidobacteria possesses an inventory of genes involved in diverse metabolic pathways, as evidenced by their pan-genomic profiles. Because of their preponderance and ubiquity in the soil, speculations have been made regarding their dynamic roles in vital ecological processes viz., regulation of biogeochemical cycles, decomposition of biopolymers, exopolysaccharide secretion, and plant growth promotion. These bacteria are expected to have genes that might help in survival and competitive colonization in the rhizosphere, leading to the establishment of beneficial relationships with plants. Exploration of these genetic attributes and more in-depth insights into the belowground mechanics and dynamics would lead to a better understanding of the functions and ecological significance of this enigmatic phylum in the soil-plant environment. This review is an effort to provide a recent update into the diversity of genes in Acidobacteria useful for characterization, understanding ecological roles, and future biotechnological perspectives.
Collapse
Affiliation(s)
- Sadaf Kalam
- Department of Biochemistry, St. Ann's College for Women, Hyderabad, India
| | - Anirban Basu
- Department of Plant Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Iqbal Ahmad
- Department of Agricultural Microbiology, Aligarh Muslim University, Aligarh, India
| | - R Z Sayyed
- Department of Microbiology, PSGVP Mandal's, Arts, Science and Commerce College, Shahada, India
| | - Hesham Ali El-Enshasy
- Institute of Bioproduct Development, Universiti Teknologi Malaysia (UTM), Skudai, Malaysia.,School of Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Skudai, Malaysia.,City of Scientific Research and Technological Applications, New Borg El-Arab, Egypt
| | - Daniel Joe Dailin
- Institute of Bioproduct Development, Universiti Teknologi Malaysia (UTM), Skudai, Malaysia.,School of Chemical and Energy Engineering, Faculty of Engineering, Universiti Teknologi Malaysia (UTM), Skudai, Malaysia
| | - Ni Luh Suriani
- Biology Department, Faculty of Mathematics and Natural Science, Udayana University, Bali, Indonesia
| |
Collapse
|
10
|
Kitoh-Nishioka H, Shigeta Y, Itoh S, Kimura A. Excitonic Coupling on a Heliobacterial Symmetrical Type-I Reaction Center: Comparison with Photosystem I. J Phys Chem B 2019; 124:389-403. [DOI: 10.1021/acs.jpcb.9b11290] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Hirotaka Kitoh-Nishioka
- JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
- Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan
| | - Yasuteru Shigeta
- Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8571, Japan
| | - Shigeru Itoh
- Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Akihiro Kimura
- Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| |
Collapse
|
11
|
Martinez JN, Nishihara A, Lichtenberg M, Trampe E, Kawai S, Tank M, Kühl M, Hanada S, Thiel V. Vertical Distribution and Diversity of Phototrophic Bacteria within a Hot Spring Microbial Mat (Nakabusa Hot Springs, Japan). Microbes Environ 2019; 34:374-387. [PMID: 31685759 PMCID: PMC6934398 DOI: 10.1264/jsme2.me19047] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Phototrophic microbial mats are assemblages of vertically layered microbial populations dominated by photosynthetic microorganisms. In order to elucidate the vertical distribution and diversity of phototrophic microorganisms in a hot spring-associated microbial mat in Nakabusa (Japan), we analyzed the 16S rRNA gene amplicon sequences of the microbial mat separated into five depth horizons, and correlated them with microsensor measurements of O2 and spectral scalar irradiance. A stable core community and high diversity of phototrophic organisms dominated by the filamentous anoxygenic phototrophs, Roseiflexus castenholzii and Chloroflexus aggregans were identified together with the spectral signatures of bacteriochlorophylls (BChls) a and c absorption in all mat layers. In the upper mat layers, a high abundance of cyanobacteria (Thermosynechococcus sp.) correlated with strong spectral signatures of chlorophyll a and phycobiliprotein absorption near the surface in a zone of high O2 concentrations during the day. Deeper mat layers were dominated by uncultured chemotrophic Chlorobi such as the novel putatively sulfate-reducing “Ca. Thermonerobacter sp.”, which showed increasing abundance with depth correlating with low O2 in these layers enabling anaerobic metabolism. Oxygen tolerance and requirements for the novel phototroph “Ca. Chloroanaerofilum sp.” and the uncultured chemotrophic Armatimonadetes member type OS-L detected in Nakabusa hot springs, Japan appeared to differ from previously suggested lifestyles for close relatives identified in hot springs in Yellowstone National Park, USA. The present study identified various microenvironmental gradients and niche differentiation enabling the co-existence of diverse chlorophototrophs in metabolically diverse communities in hot springs.
Collapse
Affiliation(s)
- Joval N Martinez
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University.,Department of Natural Sciences, College of Arts and Sciences, University of St. La Salle
| | - Arisa Nishihara
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University.,Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Mads Lichtenberg
- Marine Biological Section, Department of Biology, University of Copenhagen
| | - Erik Trampe
- Marine Biological Section, Department of Biology, University of Copenhagen
| | - Shigeru Kawai
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University
| | - Marcus Tank
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University
| | - Michael Kühl
- Marine Biological Section, Department of Biology, University of Copenhagen
| | - Satoshi Hanada
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University
| | - Vera Thiel
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University
| |
Collapse
|
12
|
He Z, Ferlez B, Kurashov V, Tank M, Golbeck JH, Bryant DA. Reaction centers of the thermophilic microaerophile, Chloracidobacterium thermophilum (Acidobacteria) I: biochemical and biophysical characterization. PHOTOSYNTHESIS RESEARCH 2019; 142:87-103. [PMID: 31161318 DOI: 10.1007/s11120-019-00650-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 05/27/2019] [Indexed: 06/09/2023]
Abstract
Chloracidobacterium thermophilum is a microaerophilic, anoxygenic member of the green chlorophototrophic bacteria. This bacterium is the first characterized oxygen-requiring chlorophototroph with chlorosomes, the FMO protein, and homodimeric type-1 reaction centers (RCs). The RCs of C. thermophilum are also unique because they contain three types of chlorophylls, bacteriochlorophyll aP esterified with phytol, Chl aPD esterified with Δ2,6-phytadienol, and Zn-BChl aP' esterified with phytol, in the approximate molar ratio 32:24:4. The light-induced difference spectrum of these RCs had a bleaching maximum at 839 nm and also revealed an electrochromic bandshift that is probably derived from a BChl a molecule near P840+. The FX [4Fe-4S] cluster had a midpoint potential of ca. - 581 mV, and the spectroscopic properties of the P+ F X - spin-polarized radical pair were very similar to those of reaction centers of heliobacteria and green sulfur bacteria. The data further indicate that electron transfer occurs directly from A0- to FX, as occurs in other homodimeric type-1 RCs. Washing experiments with isolated membranes suggested that the PscB subunit of these reaction centers is more tightly bound than PshB in heliobacteria. Thus, the reaction centers of C. thermophilum have some properties that resemble other homodimeric reaction centers but also have specific properties that are more similar to those of Photosystem I. These differences probably contribute to protection of the electron transfer chain from oxygen, contributing to the oxygen tolerance of this microaerophile.
Collapse
Affiliation(s)
- Zhihui He
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
| | - Bryan Ferlez
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI, 48824, USA
| | - Vasily Kurashov
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
| | - Marcus Tank
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo, 192-0397, Japan
| | - John H Golbeck
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, S-002 Frear Building, University Park, PA, 16802, USA.
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717, USA.
| |
Collapse
|
13
|
Roy C, Bakshi U, Rameez MJ, Mandal S, Haldar PK, Pyne P, Ghosh W. Phylogenomics of an uncultivated, aerobic and thermophilic, photoheterotrophic member of Chlorobia sheds light into the evolution of the phylum Chlorobi. Comput Biol Chem 2019; 80:206-216. [DOI: 10.1016/j.compbiolchem.2019.04.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 03/31/2019] [Accepted: 04/01/2019] [Indexed: 11/28/2022]
|
14
|
Soil bacterial diversity is positively associated with air temperature in the maritime Antarctic. Sci Rep 2019; 9:2686. [PMID: 30804443 PMCID: PMC6389919 DOI: 10.1038/s41598-019-39521-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 01/25/2019] [Indexed: 02/01/2023] Open
Abstract
Terrestrial ecosystems in the maritime Antarctic experienced rapid warming during the latter half of the 20th century. While warming ceased at the turn of the millennium, significant increases in air temperature are expected later this century, with predicted positive effects on soil fungal diversity, plant growth and ecosystem productivity. Here, by sequencing 16S ribosomal RNA genes in 40 soils sampled from along a 1,650 km climatic gradient through the maritime Antarctic, we determine whether rising air temperatures might similarly influence the diversity of soil bacteria. Of 22 environmental factors, mean annual surface air temperature was the strongest and most consistent predictor of soil bacterial diversity. Significant, but weaker, associations between bacterial diversity and soil moisture content, C:N ratio, and Ca, Mg, PO43− and dissolved organic C concentrations were also detected. These findings indicate that further rises in air temperature in the maritime Antarctic may enhance terrestrial ecosystem productivity through positive effects on soil bacterial diversity.
Collapse
|
15
|
Orf GS, Gisriel C, Redding KE. Evolution of photosynthetic reaction centers: insights from the structure of the heliobacterial reaction center. PHOTOSYNTHESIS RESEARCH 2018; 138:11-37. [PMID: 29603081 DOI: 10.1007/s11120-018-0503-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 03/22/2018] [Indexed: 05/24/2023]
Abstract
The proliferation of phototrophy within early-branching prokaryotes represented a significant step forward in metabolic evolution. All available evidence supports the hypothesis that the photosynthetic reaction center (RC)-the pigment-protein complex in which electromagnetic energy (i.e., photons of visible or near-infrared light) is converted to chemical energy usable by an organism-arose once in Earth's history. This event took place over 3 billion years ago and the basic architecture of the RC has diversified into the distinct versions that now exist. Using our recent 2.2-Å X-ray crystal structure of the homodimeric photosynthetic RC from heliobacteria, we have performed a robust comparison of all known RC types with available structural data. These comparisons have allowed us to generate hypotheses about structural and functional aspects of the common ancestors of extant RCs and to expand upon existing evolutionary schemes. Since the heliobacterial RC is homodimeric and loosely binds (and reduces) quinones, we support the view that it retains more ancestral features than its homologs from other groups. In the evolutionary scenario we propose, the ancestral RC predating the division between Type I and Type II RCs was homodimeric, loosely bound two mobile quinones, and performed an inefficient disproportionation reaction to reduce quinone to quinol. The changes leading to the diversification into Type I and Type II RCs were separate responses to the need to optimize this reaction: the Type I lineage added a [4Fe-4S] cluster to facilitate double reduction of a quinone, while the Type II lineage heterodimerized and specialized the two cofactor branches, fixing the quinone in the QA site. After the Type I/II split, an ancestor to photosystem I fixed its quinone sites and then heterodimerized to bind PsaC as a new subunit, as responses to rising O2 after the appearance of the oxygen-evolving complex in an ancestor of photosystem II. These pivotal events thus gave rise to the diversity that we observe today.
Collapse
Affiliation(s)
- Gregory S Orf
- School of Molecular Sciences, Arizona State University, Tempe, AZ, 85287, USA
- Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, AZ, 85287, USA
| | - Christopher Gisriel
- School of Molecular Sciences, Arizona State University, Tempe, AZ, 85287, USA
- Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, AZ, 85287, USA
- The Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ, 85287, USA
| | - Kevin E Redding
- School of Molecular Sciences, Arizona State University, Tempe, AZ, 85287, USA.
- Center for Bioenergy and Photosynthesis, Arizona State University, Tempe, AZ, 85287, USA.
| |
Collapse
|
16
|
The type IV pilus assembly motor PilB is a robust hexameric ATPase with complex kinetics. Biochem J 2018; 475:1979-1993. [PMID: 29717025 DOI: 10.1042/bcj20180167] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 04/23/2018] [Accepted: 05/01/2018] [Indexed: 01/06/2023]
Abstract
The bacterial type IV pilus (T4P) is a versatile nanomachine that functions in pathogenesis, biofilm formation, motility, and horizontal gene transfer. T4P assembly is powered by the motor ATPase PilB which is proposed to hydrolyze ATP by a symmetrical rotary mechanism. This mechanism, which is deduced from the structure of PilB, is untested. Here, we report the first kinetic studies of the PilB ATPase, supporting co-ordination among the protomers of this hexameric enzyme. Analysis of the genome sequence of Chloracidobacterium thermophilum identified a pilB gene whose protein we then heterologously expressed. This PilB formed a hexamer in solution and exhibited highly robust ATPase activity. It displays complex steady-state kinetics with an incline followed by a decline over an ATP concentration range of physiological relevance. The incline is multiphasic and the decline signifies substrate inhibition. These observations suggest that variations in intracellular ATP concentrations may regulate T4P assembly and T4P-mediated functions in vivo in accordance with the physiological state of bacteria with unanticipated complexity. We also identified a mutant pilB gene in the genomic DNA of C. thermophilum from an enrichment culture. The mutant PilB variant, which is significantly less active, exhibited similar inhibition of its ATPase activity by high concentrations of ATP. Our findings here with the PilB ATPase from C. thermophilum provide the first line of biochemical evidence for the co-ordination among PilB protomers consistent with the symmetrical rotary model of catalysis based on structural studies.
Collapse
|
17
|
Hausmann B, Pelikan C, Herbold CW, Köstlbacher S, Albertsen M, Eichorst SA, Glavina Del Rio T, Huemer M, Nielsen PH, Rattei T, Stingl U, Tringe SG, Trojan D, Wentrup C, Woebken D, Pester M, Loy A. Peatland Acidobacteria with a dissimilatory sulfur metabolism. THE ISME JOURNAL 2018; 12:1729-1742. [PMID: 29476143 PMCID: PMC6018796 DOI: 10.1038/s41396-018-0077-1] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 12/21/2017] [Accepted: 01/20/2018] [Indexed: 12/25/2022]
Abstract
Sulfur-cycling microorganisms impact organic matter decomposition in wetlands and consequently greenhouse gas emissions from these globally relevant environments. However, their identities and physiological properties are largely unknown. By applying a functional metagenomics approach to an acidic peatland, we recovered draft genomes of seven novel Acidobacteria species with the potential for dissimilatory sulfite (dsrAB, dsrC, dsrD, dsrN, dsrT, dsrMKJOP) or sulfate respiration (sat, aprBA, qmoABC plus dsr genes). Surprisingly, the genomes also encoded DsrL, which so far was only found in sulfur-oxidizing microorganisms. Metatranscriptome analysis demonstrated expression of acidobacterial sulfur-metabolism genes in native peat soil and their upregulation in diverse anoxic microcosms. This indicated an active sulfate respiration pathway, which, however, might also operate in reverse for dissimilatory sulfur oxidation or disproportionation as proposed for the sulfur-oxidizing Desulfurivibrio alkaliphilus. Acidobacteria that only harbored genes for sulfite reduction additionally encoded enzymes that liberate sulfite from organosulfonates, which suggested organic sulfur compounds as complementary energy sources. Further metabolic potentials included polysaccharide hydrolysis and sugar utilization, aerobic respiration, several fermentative capabilities, and hydrogen oxidation. Our findings extend both, the known physiological and genetic properties of Acidobacteria and the known taxonomic diversity of microorganisms with a DsrAB-based sulfur metabolism, and highlight new fundamental niches for facultative anaerobic Acidobacteria in wetlands based on exploitation of inorganic and organic sulfur molecules for energy conservation.
Collapse
Affiliation(s)
- Bela Hausmann
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
- Department of Biology, University of Konstanz, Konstanz, Germany
| | - Claus Pelikan
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| | - Craig W Herbold
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| | - Stephan Köstlbacher
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| | - Mads Albertsen
- Department of Chemistry and Bioscience, Center for Microbial Communities, Aalborg University, Aalborg, Denmark
| | - Stephanie A Eichorst
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| | | | - Martin Huemer
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| | - Per H Nielsen
- Department of Chemistry and Bioscience, Center for Microbial Communities, Aalborg University, Aalborg, Denmark
| | - Thomas Rattei
- Division of Computational Systems Biology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| | - Ulrich Stingl
- Department for Microbiology and Cell Science, Fort Lauderdale Research and Education Center, UF/IFAS, University of Florida, Davie, FL, USA
| | - Susannah G Tringe
- US Department of Energy Joint Genome Institute, Walnut Creek, CA, USA
| | - Daniela Trojan
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| | - Cecilia Wentrup
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| | - Dagmar Woebken
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| | - Michael Pester
- Department of Biology, University of Konstanz, Konstanz, Germany.
- Leibniz Institute DSMZ, Braunschweig, Germany.
| | - Alexander Loy
- Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, Research Network Chemistry meets Microbiology, University of Vienna, Vienna, Austria
| |
Collapse
|
18
|
Thiel V, Tank M, Bryant DA. Diversity of Chlorophototrophic Bacteria Revealed in the Omics Era. ANNUAL REVIEW OF PLANT BIOLOGY 2018; 69:21-49. [PMID: 29505738 DOI: 10.1146/annurev-arplant-042817-040500] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Because of recent advances in omics methodologies, knowledge of chlorophototrophy (i.e., chlorophyll-based phototrophy) in bacteria has rapidly increased. Chlorophototrophs currently are known to occur in seven bacterial phyla: Cyanobacteria, Proteobacteria, Chlorobi, Chloroflexi, Firmicutes, Acidobacteria, and Gemmatimonadetes. Other organisms that can produce chlorophylls and photochemical reaction centers may still be undiscovered. Here we summarize the current status of the taxonomy and phylogeny of chlorophototrophic bacteria as revealed by genomic methods. In specific cases, we briefly describe important ecophysiological and metabolic insights that have been gained from the application of genomic methods to these bacteria. In the 20 years since the completion of the Synechocystis sp. PCC 6803 genome in 1996, approximately 1,100 genomes have been sequenced, which represents nearly the complete diversity of known chlorophototrophic bacteria. These data are leading to new insights into many important processes, including photosynthesis, nitrogen and carbon fixation, cellular differentiation and development, symbiosis, and ecosystem functionality.
Collapse
Affiliation(s)
- Vera Thiel
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan; ,
| | - Marcus Tank
- Department of Biological Sciences, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397, Japan; ,
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA;
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, USA
| |
Collapse
|
19
|
Lee LS, Goh KM, Chan CS, Annie Tan GY, Yin WF, Chong CS, Chan KG. Microbial diversity of thermophiles with biomass deconstruction potential in a foliage-rich hot spring. Microbiologyopen 2018; 7:e00615. [PMID: 29602271 PMCID: PMC6291792 DOI: 10.1002/mbo3.615] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 01/29/2018] [Accepted: 02/12/2018] [Indexed: 11/12/2022] Open
Abstract
The ability of thermophilic microorganisms and their enzymes to decompose biomass have attracted attention due to their quick reaction time, thermostability, and decreased risk of contamination. Exploitation of efficient thermostable glycoside hydrolases (GHs) could accelerate the industrialization of biofuels and biochemicals. However, the full spectrum of thermophiles and their enzymes that are important for biomass degradation at high temperatures have not yet been thoroughly studied. We examined a Malaysian Y-shaped Sungai Klah hot spring located within a wooded area. The fallen foliage that formed a thick layer of biomass bed under the heated water of the Y-shaped Sungai Klah hot spring was an ideal environment for the discovery and analysis of microbial biomass decay communities. We sequenced the hypervariable regions of bacterial and archaeal 16S rRNA genes using total community DNA extracted from the hot spring. Data suggested that 25 phyla, 58 classes, 110 orders, 171 families, and 328 genera inhabited this hot spring. Among the detected genera, members of Acidimicrobium, Aeropyrum, Caldilinea, Caldisphaera, Chloracidobacterium, Chloroflexus, Desulfurobacterium, Fervidobacterium, Geobacillus, Meiothermus, Melioribacter, Methanothermococcus, Methanotorris, Roseiflexus, Thermoanaerobacter, Thermoanaerobacterium, Thermoanaerobaculum, and Thermosipho were the main thermophiles containing various GHs that play an important role in cellulose and hemicellulose breakdown. Collectively, the results suggest that the microbial community in this hot spring represents a good source for isolating efficient biomass degrading thermophiles and thermozymes.
Collapse
Affiliation(s)
- Li Sin Lee
- ISB (Genetics), Faculty of Science, University of Malaysia, Kuala Lumpur, Malaysia
| | - Kian Mau Goh
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia
| | - Chia Sing Chan
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia
| | - Geok Yuan Annie Tan
- ISB (Genetics), Faculty of Science, University of Malaysia, Kuala Lumpur, Malaysia
| | - Wai-Fong Yin
- ISB (Genetics), Faculty of Science, University of Malaysia, Kuala Lumpur, Malaysia
| | - Chun Shiong Chong
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia
| | - Kok-Gan Chan
- ISB (Genetics), Faculty of Science, University of Malaysia, Kuala Lumpur, Malaysia.,Jiangsu University, Zhenjiang, China
| |
Collapse
|
20
|
Eichorst SA, Trojan D, Roux S, Herbold C, Rattei T, Woebken D. Genomic insights into the Acidobacteria reveal strategies for their success in terrestrial environments. Environ Microbiol 2018; 20:1041-1063. [PMID: 29327410 PMCID: PMC5900883 DOI: 10.1111/1462-2920.14043] [Citation(s) in RCA: 149] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 12/16/2017] [Accepted: 01/08/2018] [Indexed: 12/11/2022]
Abstract
Members of the phylum Acidobacteria are abundant and ubiquitous across soils. We performed a large-scale comparative genome analysis spanning subdivisions 1, 3, 4, 6, 8 and 23 (n = 24) with the goal to identify features to help explain their prevalence in soils and understand their ecophysiology. Our analysis revealed that bacteriophage integration events along with transposable and mobile elements influenced the structure and plasticity of these genomes. Low- and high-affinity respiratory oxygen reductases were detected in multiple genomes, suggesting the capacity for growing across different oxygen gradients. Among many genomes, the capacity to use a diverse collection of carbohydrates, as well as inorganic and organic nitrogen sources (such as via extracellular peptidases), was detected - both advantageous traits in environments with fluctuating nutrient environments. We also identified multiple soil acidobacteria with the potential to scavenge atmospheric concentrations of H2 , now encompassing mesophilic soil strains within the subdivision 1 and 3, in addition to a previously identified thermophilic strain in subdivision 4. This large-scale acidobacteria genome analysis reveal traits that provide genomic, physiological and metabolic versatility, presumably allowing flexibility and versatility in the challenging and fluctuating soil environment.
Collapse
Affiliation(s)
- Stephanie A. Eichorst
- Division of Microbial Ecology, Department of Microbiology and Ecosystem ScienceResearch Network “Chemistry Meets Biology”, University of ViennaViennaAustria
| | - Daniela Trojan
- Division of Microbial Ecology, Department of Microbiology and Ecosystem ScienceResearch Network “Chemistry Meets Biology”, University of ViennaViennaAustria
| | - Simon Roux
- Department of EnergyJoint Genome InstituteWalnut CreekCAUSA
| | - Craig Herbold
- Division of Microbial Ecology, Department of Microbiology and Ecosystem ScienceResearch Network “Chemistry Meets Biology”, University of ViennaViennaAustria
| | - Thomas Rattei
- Division of Computational Systems Biology, Department of Microbiology and Ecosystem ScienceResearch Network “Chemistry Meets Biology”, University of ViennaViennaAustria
| | - Dagmar Woebken
- Division of Microbial Ecology, Department of Microbiology and Ecosystem ScienceResearch Network “Chemistry Meets Biology”, University of ViennaViennaAustria
| |
Collapse
|
21
|
Martin WF, Bryant DA, Beatty JT. A physiological perspective on the origin and evolution of photosynthesis. FEMS Microbiol Rev 2018; 42:205-231. [PMID: 29177446 PMCID: PMC5972617 DOI: 10.1093/femsre/fux056] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/20/2017] [Indexed: 12/22/2022] Open
Abstract
The origin and early evolution of photosynthesis are reviewed from an ecophysiological perspective. Earth's first ecosystems were chemotrophic, fueled by geological H2 at hydrothermal vents and, required flavin-based electron bifurcation to reduce ferredoxin for CO2 fixation. Chlorophyll-based phototrophy (chlorophototrophy) allowed autotrophs to generate reduced ferredoxin without electron bifurcation, providing them access to reductants other than H2. Because high-intensity, short-wavelength electromagnetic radiation at Earth's surface would have been damaging for the first chlorophyll (Chl)-containing cells, photosynthesis probably arose at hydrothermal vents under low-intensity, long-wavelength geothermal light. The first photochemically active pigments were possibly Zn-tetrapyrroles. We suggest that (i) after the evolution of red-absorbing Chl-like pigments, the first light-driven electron transport chains reduced ferredoxin via a type-1 reaction center (RC) progenitor with electrons from H2S; (ii) photothioautotrophy, first with one RC and then with two, was the bridge between H2-dependent chemolithoautotrophy and water-splitting photosynthesis; (iii) photothiotrophy sustained primary production in the photic zone of Archean oceans; (iv) photosynthesis arose in an anoxygenic cyanobacterial progenitor; (v) Chl a is the ancestral Chl; and (vi), anoxygenic chlorophototrophic lineages characterized so far acquired, by horizontal gene transfer, RCs and Chl biosynthesis with or without autotrophy, from the architects of chlorophototrophy-the cyanobacterial lineage.
Collapse
Affiliation(s)
- William F Martin
- Institute for Molecular Evolution, University of Düsseldorf, D-40225 Düsseldorf, Germany
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA
| | - J Thomas Beatty
- Department of Microbiology and Immunology, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| |
Collapse
|
22
|
Val Del Rio A, Pichel A, Fernandez-Gonzalez N, Pedrouso A, Fra-Vázquez A, Morales N, Mendez R, Campos JL, Mosquera-Corral A. Performance and microbial features of the partial nitritation-anammox process treating fish canning wastewater with variable salt concentrations. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 208:112-121. [PMID: 29253740 DOI: 10.1016/j.jenvman.2017.12.007] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Revised: 10/31/2017] [Accepted: 12/04/2017] [Indexed: 06/07/2023]
Abstract
The partial nitritation-anammox (PN-AMX) process applied to wastewaters with high NaCl concentration was studied until now using simulated media, without considering the effect of organic matter concentration and the shift in microbial populations. This research work presents results on the application of this process to the treatment of saline industrial wastewater. Obtained results indicated that the PN-AMX process has the capability to recover its initial activity after a sudden/acute salt inhibition event (up to 16 g NaCl/L). With a progressive salt concentration increase for 150 days, the PN-AMX process was able to remove the 80% of the nitrogen at 7-9 g NaCl/L. The microbiological data indicated that NaCl and ammonia concentrations and temperature are important factors shaping PN-AMX communities. Thus, the NOB abundance (Nitrospira) decreases with the increase of the salt concentration, while heterotrophic denitrifiers are able to outcompete anammox after a peak of organic matter in the feeding.
Collapse
Affiliation(s)
- Angeles Val Del Rio
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, E- 15705 Santiago de Compostela, Spain.
| | - Andres Pichel
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, E- 15705 Santiago de Compostela, Spain.
| | - Nuria Fernandez-Gonzalez
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, E- 15705 Santiago de Compostela, Spain.
| | - Alba Pedrouso
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, E- 15705 Santiago de Compostela, Spain.
| | - Andrea Fra-Vázquez
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, E- 15705 Santiago de Compostela, Spain.
| | - Nicolas Morales
- Aqualia, Guillarei WWTP, Camino de la Veiga s/n, E-36720 Tui, Spain.
| | - Ramon Mendez
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, E- 15705 Santiago de Compostela, Spain.
| | - Jose Luis Campos
- Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Avda Padre Hurtado 750, Viña del Mar, E- 2503500, Chile.
| | - Anuska Mosquera-Corral
- Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, E- 15705 Santiago de Compostela, Spain.
| |
Collapse
|
23
|
Pierella Karlusich JJ, Carrillo N. Evolution of the acceptor side of photosystem I: ferredoxin, flavodoxin, and ferredoxin-NADP + oxidoreductase. PHOTOSYNTHESIS RESEARCH 2017; 134:235-250. [PMID: 28150152 DOI: 10.1007/s11120-017-0338-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 01/12/2017] [Indexed: 05/21/2023]
Abstract
The development of oxygenic photosynthesis by primordial cyanobacteria ~2.7 billion years ago led to major changes in the components and organization of photosynthetic electron transport to cope with the challenges of an oxygen-enriched atmosphere. We review herein, following the seminal contributions as reported by Jaganathan et al. (Functional genomics and evolution of photosynthetic systems, vol 33, advances in photosynthesis and respiration, Springer, Dordrecht, 2012), how these changes affected carriers and enzymes at the acceptor side of photosystem I (PSI): the electron shuttle ferredoxin (Fd), its isofunctional counterpart flavodoxin (Fld), their redox partner ferredoxin-NADP+ reductase (FNR), and the primary PSI acceptors F x and F A/F B. Protection of the [4Fe-4S] centers of these proteins from oxidative damage was achieved by strengthening binding between the F A/F B polypeptide and the reaction center core containing F x, therefore impairing O2 access to the clusters. Immobilization of F A/F B in the PSI complex led in turn to the recruitment of new soluble electron shuttles. This function was fulfilled by oxygen-insensitive [2Fe-2S] Fd, in which the reactive sulfide atoms of the cluster are shielded from solvent by the polypeptide backbone, and in some algae and cyanobacteria by Fld, which employs a flavin as prosthetic group and is tolerant to oxidants and iron limitation. Tight membrane binding of FNR allowed solid-state electron transfer from PSI bridged by Fd/Fld. Fine tuning of FNR catalytic mechanism led to formidable increases in turnover rates compared with FNRs acting in heterotrophic pathways, favoring Fd/Fld reduction instead of oxygen reduction.
Collapse
Affiliation(s)
- Juan José Pierella Karlusich
- Instituto de Biología Molecular y Celular de Rosario (IBR-UNR/CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda, 2000, Rosario, Argentina
| | - Néstor Carrillo
- Instituto de Biología Molecular y Celular de Rosario (IBR-UNR/CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda, 2000, Rosario, Argentina.
| |
Collapse
|
24
|
Draft Genome Sequence of Anoxybacillusayderensis Strain MT-Cab ( Firmicutes). GENOME ANNOUNCEMENTS 2017; 5:5/26/e00547-17. [PMID: 28663291 PMCID: PMC5638275 DOI: 10.1128/genomea.00547-17] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The draft genome of the Gram-positive spore-forming Anoxybacillus ayderensis strain MT-Cab (Firmicutes), isolated from an enrichment culture of Chloracidobacterium thermophilum, was sequenced and comprises 2,577,015 bp in 92 contigs. The draft genome is predicted to consist of 2,699 protein-coding genes, 73 tRNA-coding genes, and an estimated 8 rRNA operons.
Collapse
|
25
|
Damsté JSS, Rijpstra WIC, Dedysh SN, Foesel BU, Villanueva L. Pheno- and Genotyping of Hopanoid Production in Acidobacteria. Front Microbiol 2017; 8:968. [PMID: 28642737 PMCID: PMC5462960 DOI: 10.3389/fmicb.2017.00968] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 05/15/2017] [Indexed: 11/28/2022] Open
Abstract
Hopanoids are pentacyclic triterpenoid lipids synthesized by different bacterial groups. Methylated hopanoids were believed to be exclusively synthesized by cyanobacteria and aerobic methanotrophs until the genes encoding for the methylation at the C-2 and C-3 position (hpnP and hpnR) were found to be widespread in the bacterial domain, invalidating their use as specific biomarkers. These genes have been detected in the genome of the Acidobacterium "Ca. Koribacter versatilis," but our knowledge of the synthesis of hopanoids and the presence of genes of their biosynthetic pathway in other member of the Acidobacteria is limited. We analyzed 38 different strains of seven Acidobacteria subdivisions (SDs 1, 3, 4, 6, 8, 10, and 23) for the presence of C30 hopenes and C30+ bacteriohopane polyols (BHPs) using the Rohmer reaction. BHPs and/or C30 hopenes were detected in all strains of SD1 and SD3 but not in SD4 (excepting Chloracidobacterium thermophilum), 6, 8, 10, and 23. This is in good agreement with the presence of genes required for hopanoid biosynthesis in the 31 available whole genomes of cultivated Acidobacteria. All genomes encode the enzymes involved in the non-mevalonate pathway ultimately leading to farnesyl diphosphate but only SD1 and 3 Acidobacteria and C. thermophilum encode all three enzymes required for the synthesis of squalene, its cyclization (shc), and addition and modification of the extended side chain (hpnG, hpnH, hpnI, hpnJ, hpnO). In almost all strains, only tetrafunctionalized BHPs were detected; three strains contained variable relative abundances (up to 45%) of pentafunctionalized BHPs. Only "Ca. K. versatilis" contained methylated hopanoids (i.e., 2,3-dimethyl bishomohopanol), although in low (<10%) amounts. These genes are not present in any other Acidobacterium, consistent with the absence of methylated BHPs in the other examined strains. These data are in agreement with the scattered occurrence of methylated BHPs in other bacterial phyla such as the Alpha-, Beta-, and Gammaproteobacteria and the Cyanobacteria, limiting their biomarker potential. Metagenomes of Acidobacteria were also examined for the presence of genes required for hopanoid biosynthesis. The complete pathway for BHP biosynthesis was evident in SD2 Acidobacteria and a group phylogenetically related to SD1 and SD3, in line with the limited occurrence of BHPs in acidobacterial cultures.
Collapse
Affiliation(s)
- Jaap S. Sinninghe Damsté
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, Utrecht UniversityDen Burg, Netherlands
- Department of Earth Sciences, Geochemistry, Faculty of Geosciences, Utrecht UniversityUtrecht, Netherlands
| | - W. Irene C. Rijpstra
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, Utrecht UniversityDen Burg, Netherlands
| | - Svetlana N. Dedysh
- S. N. Winogradsky Institute of Microbiology, Research Center of Biotechnology of Russian Academy of SciencesMoscow, Russia
| | - Bärbel U. Foesel
- Department of Microbial Ecology and Diversity Research, German Collection of Microorganisms and Cell Cultures (LG)Braunschweig, Germany
| | - Laura Villanueva
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, Utrecht UniversityDen Burg, Netherlands
| |
Collapse
|
26
|
Thiel V, Hügler M, Ward DM, Bryant DA. The Dark Side of the Mushroom Spring Microbial Mat: Life in the Shadow of Chlorophototrophs. II. Metabolic Functions of Abundant Community Members Predicted from Metagenomic Analyses. Front Microbiol 2017. [PMID: 28634470 PMCID: PMC5459899 DOI: 10.3389/fmicb.2017.00943] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microbial mat communities in the effluent channels of Octopus and Mushroom Springs within the Lower Geyser Basin of Yellowstone National Park have been extensively characterized. Previous studies have focused on the chlorophototrophic organisms of the phyla Cyanobacteria and Chloroflexi. However, the diversity and metabolic functions of the other portion of the community in the microoxic/anoxic region of the mat are poorly understood. We recently described the diverse but extremely uneven microbial assemblage in the undermat of Mushroom Spring based on 16S rRNA amplicon sequences, which was dominated by Roseiflexus members, filamentous anoxygenic chlorophototrophs. In this study, we analyzed the orange-colored undermat portion of the community of Mushroom Spring mats in a genome-centric approach and discuss the metabolic potentials of the major members. Metagenome binning recovered partial genomes of all abundant community members, ranging in completeness from ~28 to 96%, and allowed affiliation of function with taxonomic identity even for representatives of novel and Candidate phyla. Less complete metagenomic bins correlated with high microdiversity. The undermat portion of the community was found to be a mixture of phototrophic and chemotrophic organisms, which use bicarbonate as well as organic carbon sources derived from different cell components and fermentation products. The presence of rhodopsin genes in many taxa strengthens the hypothesis that light energy is of major importance. Evidence for the usage of all four bacterial carbon fixation pathways was found in the metagenome. Nitrogen fixation appears to be limited to Synechococcus spp. in the upper mat layer and Thermodesulfovibrio sp. in the undermat, and nitrate/nitrite metabolism was limited. A closed sulfur cycle is indicated by biological sulfate reduction combined with the presence of genes for sulfide oxidation mainly in phototrophs. Finally, a variety of undermat microorganisms have genes for hydrogen production and consumption, which leads to the observed diel hydrogen concentration patterns.
Collapse
Affiliation(s)
- Vera Thiel
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University ParkPA, United States
| | - Michael Hügler
- Department Microbiology and Molecular Biology, DVGW-Technologiezentrum WasserKarlsruhe, Germany
| | - David M Ward
- Department of Land Resources and Environmental Sciences, Montana State UniversityBozeman, MT, United States
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University ParkPA, United States.,Department of Chemistry and Biochemistry, Montana State UniversityBozeman, MT, United States
| |
Collapse
|
27
|
Agrawal S, Karst SM, Gilbert EM, Horn H, Nielsen PH, Lackner S. The role of inoculum and reactor configuration for microbial community composition and dynamics in mainstream partial nitritation anammox reactors. Microbiologyopen 2017; 6. [PMID: 28296352 PMCID: PMC5552961 DOI: 10.1002/mbo3.456] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/09/2017] [Accepted: 01/25/2017] [Indexed: 11/10/2022] Open
Abstract
Implementation of partial nitritation anammox (PNA) in the mainstream (municipal wastewater treatment) is still under investigation. Microbial community structure and reactor type can influence the performance of PNA reactor; yet, little is known about the role of the community composition of the inoculum and the reactor configuration under mainstream conditions. Therefore, this study investigated the community structure of inocula of different origin and their consecutive community dynamics in four different lab‐scale PNA reactors with 16S rRNA gene amplicon sequencing. These reactors were operated for almost 1 year and subjected to realistic seasonal temperature fluctuations as in moderate climate regions, that is, from 20°C in summer to 10°C in winter. The sequencing analysis revealed that the bacterial community in the reactors comprised: (1) a nitrifying community (consisting of anaerobic ammonium‐oxidizing bacteria (AnAOB), ammonia‐oxidizing bacteria (AOB), and nitrite‐oxidizing bacteria (NOB)); (2) different heterotrophic denitrifying bacteria and other putative heterotrophic bacteria (HB). The nitrifying community was the same in all four reactors at the genus level, although the biomasses were of different origin. Community dynamics revealed a stable community in the moving bed biofilm reactors (MBBR) in contrast to the sequencing batch reactors (SBR) at the genus level. Moreover, the reactor design seemed to influence the community dynamics, and reactor operation significantly influenced the overall community composition. The MBBR seems to be the reactor type of choice for mainstream wastewater treatment.
Collapse
Affiliation(s)
- Shelesh Agrawal
- Technische Universität Darmstadt, Institute IWAR, Chair of Wastewater Engineering, Darmstadt, Germany.,Karlsruhe Institute of Technology, Engler-Bunte-Institut, Chair for Water Chemistry and Water Technology, Karlsruhe, Germany
| | - Søren M Karst
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Eva M Gilbert
- Karlsruhe Institute of Technology, Engler-Bunte-Institut, Chair for Water Chemistry and Water Technology, Karlsruhe, Germany.,EnviroChemie GmbH, Rossdorf, Germany
| | - Harald Horn
- Karlsruhe Institute of Technology, Engler-Bunte-Institut, Chair for Water Chemistry and Water Technology, Karlsruhe, Germany
| | - Per H Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Aalborg, Denmark
| | - Susanne Lackner
- Technische Universität Darmstadt, Institute IWAR, Chair of Wastewater Engineering, Darmstadt, Germany.,Karlsruhe Institute of Technology, Engler-Bunte-Institut, Chair for Water Chemistry and Water Technology, Karlsruhe, Germany
| |
Collapse
|
28
|
Draft Genome Sequence of Hydrogenibacillus schlegelii MA48, a Deep-Branching Member of the Bacilli Class of Firmicutes. GENOME ANNOUNCEMENTS 2017; 5:5/3/e00380-16. [PMID: 28104644 PMCID: PMC5255923 DOI: 10.1128/genomea.00380-16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We report here the draft genome sequence of Hydrogenibacillus schlegelii MA48, a thermophilic facultative anaerobe that can oxidize hydrogen aerobically. H. schlegelii MA48 belongs to a deep-branching clade of the Bacilli class and provides important insight into the acquisition of aerobic respiration within the Firmicutes phylum.
Collapse
|
29
|
Bouhajja E, McGuire M, Liles MR, Bataille G, Agathos SN, George IF. Identification of novel toluene monooxygenase genes in a hydrocarbon-polluted sediment using sequence- and function-based screening of metagenomic libraries. Appl Microbiol Biotechnol 2016; 101:797-808. [PMID: 27785541 DOI: 10.1007/s00253-016-7934-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 10/06/2016] [Accepted: 10/12/2016] [Indexed: 11/25/2022]
Abstract
The microbial potential for toluene degradation within sediments from a tar oil-contaminated site in Flingern, Germany, was assessed using a metagenomic approach. High molecular weight environmental DNA from contaminated sediments was extracted, purified, and cloned into fosmid and BAC vectors and transformed into Escherichia coli. The fosmid library was screened by hybridization with a PCR amplicon of the α-subunit of the toluene 4-monooxygenase gene to identify genes and pathways encoding toluene degradation. Fourteen clones were recovered from the fosmid library, among which 13 were highly divergent from known tmoA genes and several had the closest relatives among Acinetobacter species. The BAC library was transferred to the heterologous hosts Cupriavidus metallidurans (phylum Proteobacteria) and Edaphobacter aggregans (phylum Acidobacteria). The resulting libraries were screened for expression of toluene degradation in the non-degradative hosts. From expression in C. metallidurans, three novel toluene monooxygenase-encoding operons were identified that were located on IncP1 plasmids. The E. aggregans-hosted BAC library led to the isolation of a cloned genetic locus putatively derived from an Acidobacteria taxon that contained genes involved in aerobic and anaerobic toluene degradation. These data suggest the important role of plasmids in the spread of toluene degradative capacity and indicate putative novel tmoA genes present in this hydrocarbon-polluted environment.
Collapse
Affiliation(s)
- E Bouhajja
- Earth and Life Institute, Laboratoire de Génie Biologique, Université catholique de Louvain, Place Croix du Sud 2, boite L7.05.19, 1348, Louvain-la-Neuve, Belgium
| | - M McGuire
- Department of Biological Sciences, Auburn University, 101 Rouse Life Science Building, Auburn, Alabama, 36849, USA
| | - M R Liles
- Department of Biological Sciences, Auburn University, 101 Rouse Life Science Building, Auburn, Alabama, 36849, USA
| | - G Bataille
- Earth and Life Institute, Biodiversity Research Centre, Université catholique de Louvain, Place Croix du Sud 4-5, Bte L.7.07.04, 1348, Louvain-la-Neuve, Belgium
| | - S N Agathos
- Earth and Life Institute, Laboratoire de Génie Biologique, Université catholique de Louvain, Place Croix du Sud 2, boite L7.05.19, 1348, Louvain-la-Neuve, Belgium.,School of Life Sciences and Biotechnology, Yachay Tech University, San Miguel de Urcuquí, Ecuador
| | - I F George
- Laboratoire d'Ecologie des Systèmes Aquatiques, Université libre de Bruxelles, Campus de la Plaine CP 221, Boulevard du Triomphe, 1050, Brussels, Belgium.
| |
Collapse
|
30
|
Thiel V, Wood JM, Olsen MT, Tank M, Klatt CG, Ward DM, Bryant DA. The Dark Side of the Mushroom Spring Microbial Mat: Life in the Shadow of Chlorophototrophs. I. Microbial Diversity Based on 16S rRNA Gene Amplicons and Metagenomic Sequencing. Front Microbiol 2016; 7:919. [PMID: 27379049 PMCID: PMC4911352 DOI: 10.3389/fmicb.2016.00919] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 05/27/2016] [Indexed: 11/13/2022] Open
Abstract
Microbial-mat communities in the effluent channels of Octopus and Mushroom Springs within the Lower Geyser Basin at Yellowstone National Park have been studied for nearly 50 years. The emphasis has mostly focused on the chlorophototrophic bacterial organisms of the phyla Cyanobacteria and Chloroflexi. In contrast, the diversity and metabolic functions of the heterotrophic community in the microoxic/anoxic region of the mat are not well understood. In this study we analyzed the orange-colored undermat of the microbial community of Mushroom Spring using metagenomic and rRNA-amplicon (iTag) analyses. Our analyses disclosed a highly diverse community exhibiting a high degree of unevenness, strongly dominated by a single taxon, the filamentous anoxygenic phototroph, Roseiflexus spp. The second most abundant organisms belonged to the Thermotogae, which have been hypothesized to be a major source of H2 from fermentation that could enable photomixotrophic metabolism by Chloroflexus and Roseiflexus spp. Other abundant organisms include two members of the Armatimonadetes (OP10); Thermocrinis sp.; and phototrophic and heterotrophic members of the Chloroflexi. Further, an Atribacteria (OP9/JS1) member; a sulfate-reducing Thermodesulfovibrio sp.; a Planctomycetes member; a member of the EM3 group tentatively affiliated with the Thermotogae, as well as a putative member of the Arminicenantes (OP8) represented ≥1% of the reads. Archaea were not abundant in the iTag analysis, and no metagenomic bin representing an archaeon was identified. A high microdiversity of 16S rRNA gene sequences was identified for the dominant taxon, Roseiflexus spp. Previous studies demonstrated that highly similar Synechococcus variants in the upper layer of the mats represent ecological species populations with specific ecological adaptations. This study suggests that similar putative ecotypes specifically adapted to different niches occur within the undermat community, particularly for Roseiflexus spp.
Collapse
Affiliation(s)
- Vera Thiel
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University University Park, PA, USA
| | - Jason M Wood
- Department of Land Resources and Environmental Sciences, Montana State University Bozeman, MT, USA
| | - Millie T Olsen
- Department of Land Resources and Environmental Sciences, Montana State University Bozeman, MT, USA
| | - Marcus Tank
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University University Park, PA, USA
| | - Christian G Klatt
- Department of Land Resources and Environmental Sciences, Montana State UniversityBozeman, MT, USA; Agricultural Research Service, United States Department of Agriculture, University of MinnesotaSaint Paul, MN, USA
| | - David M Ward
- Department of Land Resources and Environmental Sciences, Montana State University Bozeman, MT, USA
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, The Pennsylvania State UniversityUniversity Park, PA, USA; Department of Chemistry and Biochemistry, Montana State UniversityBozeman, MT, USA
| |
Collapse
|
31
|
Kielak AM, Barreto CC, Kowalchuk GA, van Veen JA, Kuramae EE. The Ecology of Acidobacteria: Moving beyond Genes and Genomes. Front Microbiol 2016; 7:744. [PMID: 27303369 PMCID: PMC4885859 DOI: 10.3389/fmicb.2016.00744] [Citation(s) in RCA: 459] [Impact Index Per Article: 57.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 05/03/2016] [Indexed: 12/01/2022] Open
Abstract
The phylum Acidobacteria is one of the most widespread and abundant on the planet, yet remarkably our knowledge of the role of these diverse organisms in the functioning of terrestrial ecosystems remains surprisingly rudimentary. This blatant knowledge gap stems to a large degree from the difficulties associated with the cultivation of these bacteria by classical means. Given the phylogenetic breadth of the Acidobacteria, which is similar to the metabolically diverse Proteobacteria, it is clear that detailed and functional descriptions of acidobacterial assemblages are necessary. Fortunately, recent advances are providing a glimpse into the ecology of members of the phylum Acidobacteria. These include novel cultivation and enrichment strategies, genomic characterization and analyses of metagenomic DNA from environmental samples. Here, we couple the data from these complementary approaches for a better understanding of their role in the environment, thereby providing some initial insights into the ecology of this important phylum. All cultured acidobacterial type species are heterotrophic, and members of subdivisions 1, 3, and 4 appear to be more versatile in carbohydrate utilization. Genomic and metagenomic data predict a number of ecologically relevant capabilities for some acidobacteria, including the ability to: use of nitrite as N source, respond to soil macro-, micro nutrients and soil acidity, express multiple active transporters, degrade gellan gum and produce exopolysaccharide (EPS). Although these predicted properties allude to a competitive life style in soil, only very few of these prediction shave been confirmed via physiological studies. The increased availability of genomic and physiological information, coupled to distribution data in field surveys and experiments, should direct future progress in unraveling the ecology of this important but still enigmatic phylum.
Collapse
Affiliation(s)
- Anna M Kielak
- Department of Microbial Ecology, The Netherlands Institute of Ecology - Koninklijke Nederlandse Akademie van Wetenschappen Wageningen, Netherlands
| | - Cristine C Barreto
- Graduate Program in Genomic Sciences and Biotechnology, Universidade Católica de Brasília Brasília, Brazil
| | - George A Kowalchuk
- Ecology and Biodiversity Group, University of Utrecht Utrecht, Netherlands
| | - Johannes A van Veen
- Department of Microbial Ecology, The Netherlands Institute of Ecology - Koninklijke Nederlandse Akademie van Wetenschappen Wageningen, Netherlands
| | - Eiko E Kuramae
- Department of Microbial Ecology, The Netherlands Institute of Ecology - Koninklijke Nederlandse Akademie van Wetenschappen Wageningen, Netherlands
| |
Collapse
|
32
|
Conjugative transfer of broad host range plasmids to an acidobacterial strain, Edaphobacter aggregans. J Biotechnol 2016; 221:107-13. [DOI: 10.1016/j.jbiotec.2016.01.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 01/18/2016] [Accepted: 01/20/2016] [Indexed: 01/19/2023]
|
33
|
Draft Genome Sequence of the Photoheterotrophic Chloracidobacterium thermophilum Strain OC1 Found in a Mat at Ojo Caliente. GENOME ANNOUNCEMENTS 2016; 4:4/1/e01570-15. [PMID: 26893414 PMCID: PMC4759061 DOI: 10.1128/genomea.01570-15] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Metagenomics of an enrichment culture from a New Mexico hot spring allowed the description of a draft genome of a Chloracidobacterium thermophilum strain for the first time outside Yellowstone National Park with a surprisingly high degree of identity with the type strain.
Collapse
|
34
|
Eloe-Fadrosh EA, Paez-Espino D, Jarett J, Dunfield PF, Hedlund BP, Dekas AE, Grasby SE, Brady AL, Dong H, Briggs BR, Li WJ, Goudeau D, Malmstrom R, Pati A, Pett-Ridge J, Rubin EM, Woyke T, Kyrpides NC, Ivanova NN. Global metagenomic survey reveals a new bacterial candidate phylum in geothermal springs. Nat Commun 2016; 7:10476. [PMID: 26814032 PMCID: PMC4737851 DOI: 10.1038/ncomms10476] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 12/07/2015] [Indexed: 01/01/2023] Open
Abstract
Analysis of the increasing wealth of metagenomic data collected from diverse environments can lead to the discovery of novel branches on the tree of life. Here we analyse 5.2 Tb of metagenomic data collected globally to discover a novel bacterial phylum (‘Candidatus Kryptonia') found exclusively in high-temperature pH-neutral geothermal springs. This lineage had remained hidden as a taxonomic ‘blind spot' because of mismatches in the primers commonly used for ribosomal gene surveys. Genome reconstruction from metagenomic data combined with single-cell genomics results in several high-quality genomes representing four genera from the new phylum. Metabolic reconstruction indicates a heterotrophic lifestyle with conspicuous nutritional deficiencies, suggesting the need for metabolic complementarity with other microbes. Co-occurrence patterns identifies a number of putative partners, including an uncultured Armatimonadetes lineage. The discovery of Kryptonia within previously studied geothermal springs underscores the importance of globally sampled metagenomic data in detection of microbial novelty, and highlights the extraordinary diversity of microbial life still awaiting discovery. The analysis of existing metagenomic data can lead to discovery of new microorganisms. Here, Eloe-Fadrosh et al. perform a large-scale analysis of global metagenomic data, followed by genome reconstruction and single-cell genomics, to describe a new bacterial phylum that inhabits geothermal springs.
Collapse
Affiliation(s)
| | - David Paez-Espino
- Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Jessica Jarett
- Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Peter F Dunfield
- Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada
| | - Brian P Hedlund
- School of Life Sciences, University of Nevada, Las Vegas, Las Vegas, Nevada 89154, USA
| | - Anne E Dekas
- Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | | | - Allyson L Brady
- School of Geography &Earth Sciences, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Hailiang Dong
- Department of Geology and Environmental Earth Sciences, Miami University, Oxford, Ohio 45056, USA
| | - Brandon R Briggs
- Department of Biological Sciences, University of Alaska-Anchorage, Anchorage, Alaska 99508, USA
| | - Wen-Jun Li
- School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Danielle Goudeau
- Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Rex Malmstrom
- Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Amrita Pati
- Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | | | - Edward M Rubin
- Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA.,Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Tanja Woyke
- Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Nikos C Kyrpides
- Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| | - Natalia N Ivanova
- Department of Energy Joint Genome Institute, Walnut Creek, California 94598, USA
| |
Collapse
|
35
|
López-López O, Knapik K, Cerdán ME, González-Siso MI. Metagenomics of an Alkaline Hot Spring in Galicia (Spain): Microbial Diversity Analysis and Screening for Novel Lipolytic Enzymes. Front Microbiol 2015; 6:1291. [PMID: 26635759 PMCID: PMC4653306 DOI: 10.3389/fmicb.2015.01291] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 11/04/2015] [Indexed: 01/23/2023] Open
Abstract
A fosmid library was constructed with the metagenomic DNA from the water of the Lobios hot spring (76°C, pH = 8.2) located in Ourense (Spain). Metagenomic sequencing of the fosmid library allowed the assembly of 9722 contigs ranging in size from 500 to 56,677 bp and spanning ~18 Mbp. 23,207 ORFs (Open Reading Frames) were predicted from the assembly. Biodiversity was explored by taxonomic classification and it revealed that bacteria were predominant, while the archaea were less abundant. The six most abundant bacterial phyla were Deinococcus-Thermus, Proteobacteria, Firmicutes, Acidobacteria, Aquificae, and Chloroflexi. Within the archaeal superkingdom, the phylum Thaumarchaeota was predominant with the dominant species “Candidatus Caldiarchaeum subterraneum.” Functional classification revealed the genes associated to one-carbon metabolism as the most abundant. Both taxonomic and functional classifications showed a mixture of different microbial metabolic patterns: aerobic and anaerobic, chemoorganotrophic and chemolithotrophic, autotrophic and heterotrophic. Remarkably, the presence of genes encoding enzymes with potential biotechnological interest, such as xylanases, galactosidases, proteases, and lipases, was also revealed in the metagenomic library. Functional screening of this library was subsequently done looking for genes encoding lipolytic enzymes. Six genes conferring lipolytic activity were identified and one was cloned and characterized. This gene was named LOB4Est and it was expressed in a yeast mesophilic host. LOB4Est codes for a novel esterase of family VIII, with sequence similarity to β-lactamases, but with unusual wide substrate specificity. When the enzyme was purified from the mesophilic host it showed half-life of 1 h and 43 min at 50°C, and maximal activity at 40°C and pH 7.5 with p-nitrophenyl-laurate as substrate. Interestingly, the enzyme retained more than 80% of maximal activity in a broad range of pH from 6.5 to 8.
Collapse
Affiliation(s)
- Olalla López-López
- Grupo EXPRELA, Departamento de Bioloxía Celular e Molecular, Facultade de Ciencias, Centro de Investigacións Científicas Avanzadas, Universidade da Coruña A Coruña, Spain
| | - Kamila Knapik
- Grupo EXPRELA, Departamento de Bioloxía Celular e Molecular, Facultade de Ciencias, Centro de Investigacións Científicas Avanzadas, Universidade da Coruña A Coruña, Spain
| | - Maria-Esperanza Cerdán
- Grupo EXPRELA, Departamento de Bioloxía Celular e Molecular, Facultade de Ciencias, Centro de Investigacións Científicas Avanzadas, Universidade da Coruña A Coruña, Spain
| | - María-Isabel González-Siso
- Grupo EXPRELA, Departamento de Bioloxía Celular e Molecular, Facultade de Ciencias, Centro de Investigacións Científicas Avanzadas, Universidade da Coruña A Coruña, Spain
| |
Collapse
|
36
|
Lee KCY, Morgan XC, Power JF, Dunfield PF, Huttenhower C, Stott MB. Complete genome sequence of the thermophilic Acidobacteria, Pyrinomonas methylaliphatogenes type strain K22(T). Stand Genomic Sci 2015; 10:101. [PMID: 26568784 PMCID: PMC4644332 DOI: 10.1186/s40793-015-0099-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2015] [Accepted: 11/10/2015] [Indexed: 11/10/2022] Open
Abstract
Strain K22(T) is the type species of the recently- described genus Pyrinomonas, in subdivision 4 of the phylum Acidobacteria (Int J Syst Evol Micr. 2014; 64(1):220-7). It was isolated from geothermally-heated soil from Mt. Ngauruhoe, New Zealand, using low-nutrient medium. P. methylaliphatogenes K22(T) has a chemoheterotrophic metabolism; it can hydrolyze a limited range of simple carbohydrates and polypeptides. Its cell membrane is dominated by iso-branching fatty acids, and up to 40 % of its lipid content is membrane-spanning and ether lipids. It is obligately aerobic, thermophilic, moderately acidophilic, and non-spore-forming. The 3,788,560 bp genome of P. methylaliphatogenes K22(T) has a G + C content of 59.36 % and contains 3,189 protein-encoding and 55 non-coding RNA genes. Genomic analysis was consistent with nutritional requirements; in particular, the identified transporter classes reflect the oligotrophic nature of this strain.
Collapse
Affiliation(s)
- Kevin C Y Lee
- GNS Science, Extremophiles Research Group, Taupō, New Zealand
| | - Xochitl C Morgan
- Department of Biostatistics, Harvard School of Public Health, Boston, MA USA ; Broad Institute of Harvard and MIT, Cambridge, MA USA
| | - Jean F Power
- GNS Science, Extremophiles Research Group, Taupō, New Zealand
| | - Peter F Dunfield
- Department of Biological Sciences, University of Calgary, Calgary, Canada
| | - Curtis Huttenhower
- Department of Biostatistics, Harvard School of Public Health, Boston, MA USA ; Broad Institute of Harvard and MIT, Cambridge, MA USA
| | - Matthew B Stott
- GNS Science, Extremophiles Research Group, Taupō, New Zealand
| |
Collapse
|
37
|
Ji M, van Dorst J, Bissett A, Brown MV, Palmer AS, Snape I, Siciliano SD, Ferrari BC. Microbial diversity at Mitchell Peninsula, Eastern Antarctica: a potential biodiversity “hotspot”. Polar Biol 2015. [DOI: 10.1007/s00300-015-1776-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
38
|
Hedlund BP, Murugapiran SK, Alba TW, Levy A, Dodsworth JA, Goertz GB, Ivanova N, Woyke T. Uncultivated thermophiles: current status and spotlight on 'Aigarchaeota'. Curr Opin Microbiol 2015; 25:136-45. [PMID: 26113243 DOI: 10.1016/j.mib.2015.06.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 06/03/2015] [Accepted: 06/03/2015] [Indexed: 01/28/2023]
Abstract
Meta-analysis of cultivation-independent sequence data shows that geothermal systems host an abundance of novel organisms, representing a vast unexplored phylogenetic and functional diversity among yet-uncultivated thermophiles. A number of thermophiles have recently been interrogated using metagenomic and/or single-cell genomic approaches, including members of taxonomic groups that inhabit both thermal and non-thermal environments, such as 'Acetothermia' (OP1) and 'Atribacteria' (OP9/JS1), as well as the exclusively thermophilic lineages 'Korarchaeota', 'Calescamantes' (EM19), 'Fervidibacteria' (OctSpA1-106), and 'Aigarchaeota' (HWCG-I). The 'Aigarchaeota', a sister lineage to the Thaumarchaeota, likely includes both hyperthermophiles and moderate thermophiles. They inhabit terrestrial, marine, and subsurface thermal environments and comprise at least nine genus-level lineages, several of which are globally distributed.
Collapse
Affiliation(s)
- Brian P Hedlund
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154, USA; Nevada Institute of Personalized Medicine, University of Nevada Las Vegas, Las Vegas, NV 89154, USA.
| | | | - Timothy W Alba
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154, USA
| | - Asaf Levy
- DOE Joint Genome Institute, Walnut Creek, CA 94598, USA
| | - Jeremy A Dodsworth
- Department of Biology, California State University, San Bernardino, CA 92407, USA
| | - Gisele B Goertz
- School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV 89154, USA
| | | | - Tanja Woyke
- DOE Joint Genome Institute, Walnut Creek, CA 94598, USA
| |
Collapse
|
39
|
Gasc C, Ribière C, Parisot N, Beugnot R, Defois C, Petit-Biderre C, Boucher D, Peyretaillade E, Peyret P. Capturing prokaryotic dark matter genomes. Res Microbiol 2015; 166:814-30. [PMID: 26100932 DOI: 10.1016/j.resmic.2015.06.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 06/02/2015] [Accepted: 06/03/2015] [Indexed: 11/18/2022]
Abstract
Prokaryotes are the most diverse and abundant cellular life forms on Earth. Most of them, identified by indirect molecular approaches, belong to microbial dark matter. The advent of metagenomic and single-cell genomic approaches has highlighted the metabolic capabilities of numerous members of this dark matter through genome reconstruction. Thus, linking functions back to the species has revolutionized our understanding of how ecosystem function is sustained by the microbial world. This review will present discoveries acquired through the illumination of prokaryotic dark matter genomes by these innovative approaches.
Collapse
Affiliation(s)
- Cyrielle Gasc
- Clermont Université, Université d'Auvergne, EA 4678 CIDAM, BP 10448, F-63001 Clermont-Ferrand, France.
| | - Céline Ribière
- Clermont Université, Université d'Auvergne, EA 4678 CIDAM, BP 10448, F-63001 Clermont-Ferrand, France.
| | - Nicolas Parisot
- Biologie Fonctionnelle Insectes et Interactions, UMR203 BF2I, INRA, INSA-Lyon, Université de Lyon, Villeurbanne, France.
| | - Réjane Beugnot
- Clermont Université, Université d'Auvergne, EA 4678 CIDAM, BP 10448, F-63001 Clermont-Ferrand, France.
| | - Clémence Defois
- Clermont Université, Université d'Auvergne, EA 4678 CIDAM, BP 10448, F-63001 Clermont-Ferrand, France.
| | - Corinne Petit-Biderre
- Université Blaise Pascal, Laboratoire Microorganismes, Génome et Environnement, Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 6023, F-63171 Aubière, France.
| | - Delphine Boucher
- Clermont Université, Université d'Auvergne, EA 4678 CIDAM, BP 10448, F-63001 Clermont-Ferrand, France.
| | - Eric Peyretaillade
- Clermont Université, Université d'Auvergne, EA 4678 CIDAM, BP 10448, F-63001 Clermont-Ferrand, France.
| | - Pierre Peyret
- Clermont Université, Université d'Auvergne, EA 4678 CIDAM, BP 10448, F-63001 Clermont-Ferrand, France.
| |
Collapse
|
40
|
Tank M, Bryant DA. Chloracidobacterium thermophilum gen. nov., sp. nov.: an anoxygenic microaerophilic chlorophotoheterotrophic acidobacterium. Int J Syst Evol Microbiol 2015; 65:1426-1430. [DOI: 10.1099/ijs.0.000113] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A novel anoxygenic photoheterotrophic member of the phylum
Acidobacteria
, Chloracidobacterium thermophilum strain B sp. nov., was isolated from a cyanobacterial enrichment culture derived from microbial mats associated with Octopus Spring, Yellowstone National Park, WY. C. thermophilum sp. nov. was a Gram-stain-negative rod (diameter, approximately 0.8–1.0 µm; variable length, approximately 2.5 µm), which formed greenish-brown liquid suspension cultures. It was a moderately thermophilic microaerophile and grew in a defined medium at 51 °C (Topt; range 44 to 58 °C) and in the pH range 5.5 to 9.5 (pHopt = ~7.0). The DNA G+C content was 61.3 mol%, and phylogenetic analysis, based on the 16S rRNA sequence, showed that C. thermophilum sp. nov. belongs to subdivision 4 (
Acidobacteriaceae
) of the
Acidobacteria
. C. thermophilum sp. nov. was unable to synthesize branched-chain amino acids, l-lysine, and vitamin B12, which were required for growth. Although the organism lacked genes/enzymes for autotrophic carbon fixation, bicarbonate was required. Growth was stimulated by other amino acids and 2-oxoglutarate. Cells produced chlorosomes containing a diverse mixture of bacteriochlorophyll (BChl) c derivatives, and additionally, synthesized BChl a
P, Chl a
PD, and Zn-BChl a′P, which occurred in type-1 homodimeric reaction centres. The carotenoids included echinenone, canthaxanthin, lycopene, γ-carotene and β-carotene. C. thermophilum sp. nov. produced iso-diabolic acid as its major fatty acid and synthesized three hopanoids (diploptene, bacteriohopanetetrol and bacteriohopanetetrol cyclitol ether). Based upon its phenotypic and genotypic properties, the name Chloracidobacterium thermophilum gen. nov., sp. nov. is proposed for this isolate; the type strain is C. thermophilum strain BT (ATCC BAA-2647 = JCM 30199).
Collapse
Affiliation(s)
- Marcus Tank
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802 USA
| | - Donald A. Bryant
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT, 59717 USA
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802 USA
| |
Collapse
|
41
|
Urbieta MS, Donati ER, Chan KG, Shahar S, Sin LL, Goh KM. Thermophiles in the genomic era: Biodiversity, science, and applications. Biotechnol Adv 2015; 33:633-47. [PMID: 25911946 DOI: 10.1016/j.biotechadv.2015.04.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 12/18/2014] [Accepted: 04/14/2015] [Indexed: 01/30/2023]
Abstract
Thermophiles and hyperthermophiles are present in various regions of the Earth, including volcanic environments, hot springs, mud pots, fumaroles, geysers, coastal thermal springs, and even deep-sea hydrothermal vents. They are also found in man-made environments, such as heated compost facilities, reactors, and spray dryers. Thermophiles, hyperthermophiles, and their bioproducts facilitate various industrial, agricultural, and medicinal applications and offer potential solutions to environmental damages and the demand for biofuels. Intensified efforts to sequence the entire genome of hyperthermophiles and thermophiles are increasing rapidly, as evidenced by the fact that over 120 complete genome sequences of the hyperthermophiles Aquificae, Thermotogae, Crenarchaeota, and Euryarchaeota are now available. In this review, we summarise the major current applications of thermophiles and thermozymes. In addition, emphasis is placed on recent progress in understanding the biodiversity, genomes, transcriptomes, metagenomes, and single-cell sequencing of thermophiles in the genomic era.
Collapse
Affiliation(s)
- M Sofía Urbieta
- CINDEFI (CCT La Plata-CONICET, UNLP), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, 1900 La Plata, Argentina
| | - Edgardo R Donati
- CINDEFI (CCT La Plata-CONICET, UNLP), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Calle 47 y 115, 1900 La Plata, Argentina
| | - Kok-Gan Chan
- Division of Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Saleha Shahar
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia
| | - Lee Li Sin
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia
| | - Kian Mau Goh
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Malaysia.
| |
Collapse
|
42
|
Tank M, Bryant DA. Nutrient requirements and growth physiology of the photoheterotrophic Acidobacterium, Chloracidobacterium thermophilum. Front Microbiol 2015; 6:226. [PMID: 25870589 PMCID: PMC4376005 DOI: 10.3389/fmicb.2015.00226] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 03/06/2015] [Indexed: 11/13/2022] Open
Abstract
A novel thermophilic, microaerophilic, anoxygenic, and chlorophototrophic member of the phylum Acidobacteria, Chloracidobacterium thermophilum strain B(T), was isolated from a cyanobacterial enrichment culture derived from microbial mats associated with Octopus Spring, Yellowstone National Park, Wyoming. C. thermophilum is strictly dependent on light and oxygen and grows optimally as a photoheterotroph at irradiance values between 20 and 50 μmol photons m(-2) s(-1). C. thermophilum is unable to synthesize branched-chain amino acids (AAs), l-lysine, and vitamin B12, which are required for growth. Although the organism lacks genes for autotrophic carbon fixation, bicarbonate is also required. Mixtures of other AAs and 2-oxoglutarate stimulate growth. As suggested from genomic sequence data, C. thermophilum requires a reduced sulfur source such as thioglycolate, cysteine, methionine, or thiosulfate. The organism can be grown in a defined medium at 51(∘)C (Topt; range 44-58(∘)C) in the pH range 5.5-9.5 (pHopt = ∼7.0). Using the defined growth medium and optimal conditions, it was possible to isolate new C. thermophilum strains directly from samples of hot spring mats in Yellowstone National Park, Wyoming. The new isolates differ from the type strain with respect to pigment composition, morphology in liquid culture, and temperature adaptation.
Collapse
Affiliation(s)
- Marcus Tank
- Department of Biochemistry and Molecular Biology, Eberly College of Science, The Pennsylvania State University PA, USA
| | - Donald A Bryant
- Department of Biochemistry and Molecular Biology, Eberly College of Science, The Pennsylvania State University PA, USA ; Department of Chemistry and Biochemistry, Montana State University Bozeman, MT, USA
| |
Collapse
|
43
|
Chan CS, Chan KG, Tay YL, Chua YH, Goh KM. Diversity of thermophiles in a Malaysian hot spring determined using 16S rRNA and shotgun metagenome sequencing. Front Microbiol 2015; 6:177. [PMID: 25798135 PMCID: PMC4350410 DOI: 10.3389/fmicb.2015.00177] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 02/17/2015] [Indexed: 02/04/2023] Open
Abstract
The Sungai Klah (SK) hot spring is the second hottest geothermal spring in Malaysia. This hot spring is a shallow, 150-m-long, fast-flowing stream, with temperatures varying from 50 to 110°C and a pH range of 7.0–9.0. Hidden within a wooded area, the SK hot spring is continually fed by plant litter, resulting in a relatively high degree of total organic content (TOC). In this study, a sample taken from the middle of the stream was analyzed at the 16S rRNA V3-V4 region by amplicon metagenome sequencing. Over 35 phyla were detected by analyzing the 16S rRNA data. Firmicutes and Proteobacteria represented approximately 57% of the microbiome. Approximately 70% of the detected thermophiles were strict anaerobes; however, Hydrogenobacter spp., obligate chemolithotrophic thermophiles, represented one of the major taxa. Several thermophilic photosynthetic microorganisms and acidothermophiles were also detected. Most of the phyla identified by 16S rRNA were also found using the shotgun metagenome approaches. The carbon, sulfur, and nitrogen metabolism within the SK hot spring community were evaluated by shotgun metagenome sequencing, and the data revealed diversity in terms of metabolic activity and dynamics. This hot spring has a rich diversified phylogenetic community partly due to its natural environment (plant litter, high TOC, and a shallow stream) and geochemical parameters (broad temperature and pH range). It is speculated that symbiotic relationships occur between the members of the community.
Collapse
Affiliation(s)
- Chia Sing Chan
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia Skudai, Malaysia
| | - Kok-Gan Chan
- Division of Genetics and Molecular Biology, Faculty of Science, Institute of Biological Sciences, University of Malaya Kuala Lumpur, Malaysia
| | | | | | - Kian Mau Goh
- Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia Skudai, Malaysia
| |
Collapse
|
44
|
Challacombe J, Kuske C. Mobile genetic elements in the bacterial phylum Acidobacteria. Mob Genet Elements 2014; 2:179-183. [PMID: 23087842 PMCID: PMC3469429 DOI: 10.4161/mge.21943] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Analysis of the genome of Candidatus Solibacter usitatus Ellin6076, a member of the phylum Acidobacteria, revealed a large number of genes associated with mobile genetic elements. These genes encoded transposases, insertion sequence elements and phage integrases. When the amino acid sequences of the mobile element-associated genes were compared, many of them had high (90–100%) amino acid sequence identities, suggesting that these genes may have recently duplicated and dispersed throughout the genome. Although phage integrase encoding genes were prevalent in the Can. S. usitatus Ellin6076 genome, no intact prophage regions were found. This suggests that the Can. S. usitatus Ellin6076 large genome arose by horizontal gene transfer via ancient bacteriophage and/or plasmid-mediated transduction, followed by widespread small-scale gene duplications, resulting in an increased number of paralogs encoding traits that could provide selective metabolic, defensive and regulatory advantages in the soil environment. Here we examine the mobile element repertoire of Can. S. usitatus Ellin6076 in comparison to other genomes from the Acidobacteria phylum, reviewing published studies and contributing some new analyses. We also discuss the presence and potential roles of mobile elements in members of this phylum that inhabit a variety of environments.
Collapse
Affiliation(s)
- Jean Challacombe
- Los Alamos National Laboratory; Bioscience Division; Los Alamos NM USA
| | | |
Collapse
|
45
|
Zhang Z, Liu S. Insight into the overconsumption of ammonium by anammox consortia under anaerobic conditions. J Appl Microbiol 2014; 117:1830-8. [DOI: 10.1111/jam.12649] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Revised: 09/05/2014] [Accepted: 09/05/2014] [Indexed: 11/30/2022]
Affiliation(s)
- Z. Zhang
- Department of Environmental Engineering; Peking University; Beijing China
- Key Laboratory of Water and Sediment Sciences; Ministry of Education of China; Beijing China
| | - S. Liu
- Department of Environmental Engineering; Peking University; Beijing China
- Key Laboratory of Water and Sediment Sciences; Ministry of Education of China; Beijing China
| |
Collapse
|
46
|
Dick JM, Shock EL. A metastable equilibrium model for the relative abundances of microbial phyla in a hot spring. PLoS One 2013; 8:e72395. [PMID: 24023738 PMCID: PMC3759468 DOI: 10.1371/journal.pone.0072395] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Accepted: 07/10/2013] [Indexed: 11/29/2022] Open
Abstract
Many studies link the compositions of microbial communities to their environments, but the energetics of organism-specific biomass synthesis as a function of geochemical variables have rarely been assessed. We describe a thermodynamic model that integrates geochemical and metagenomic data for biofilms sampled at five sites along a thermal and chemical gradient in the outflow channel of the hot spring known as “Bison Pool” in Yellowstone National Park. The relative abundances of major phyla in individual communities sampled along the outflow channel are modeled by computing metastable equilibrium among model proteins with amino acid compositions derived from metagenomic sequences. Geochemical conditions are represented by temperature and activities of basis species, including pH and oxidation-reduction potential quantified as the activity of dissolved hydrogen. By adjusting the activity of hydrogen, the model can be tuned to closely approximate the relative abundances of the phyla observed in the community profiles generated from BLAST assignments. The findings reveal an inverse relationship between the energy demand to form the proteins at equal thermodynamic activities and the abundance of phyla in the community. The distance from metastable equilibrium of the communities, assessed using an equation derived from energetic considerations that is also consistent with the information-theoretic entropy change, decreases along the outflow channel. Specific divergences from metastable equilibrium, such as an underprediction of the relative abundances of phototrophic organisms at lower temperatures, can be explained by considering additional sources of energy and/or differences in growth efficiency. Although the metabolisms used by many members of these communities are driven by chemical disequilibria, the results support the possibility that higher-level patterns of chemotrophic microbial ecosystems are shaped by metastable equilibrium states that depend on both the composition of biomass and the environmental conditions.
Collapse
Affiliation(s)
- Jeffrey M. Dick
- Department of Chemistry and Department of Applied Geology, Curtin University, Perth, Western Australia, Australia
- * E-mail:
| | - Everett L. Shock
- School of Earth and Space Exploration and Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona, United States of America
| |
Collapse
|
47
|
Klatt CG, Liu Z, Ludwig M, Kühl M, Jensen SI, Bryant DA, Ward DM. Temporal metatranscriptomic patterning in phototrophic Chloroflexi inhabiting a microbial mat in a geothermal spring. THE ISME JOURNAL 2013; 7:1775-89. [PMID: 23575369 PMCID: PMC3749495 DOI: 10.1038/ismej.2013.52] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Revised: 02/10/2013] [Accepted: 02/13/2013] [Indexed: 11/09/2022]
Abstract
Filamentous anoxygenic phototrophs (FAPs) are abundant members of microbial mat communities inhabiting neutral and alkaline geothermal springs. Natural populations of FAPs related to Chloroflexus spp. and Roseiflexus spp. have been well characterized in Mushroom Spring, where they occur with unicellular cyanobacteria related to Synechococcus spp. strains A and B'. Metatranscriptomic sequencing was applied to the microbial community to determine how FAPs regulate their gene expression in response to fluctuating environmental conditions and resource availability over a diel period. Transcripts for genes involved in the biosynthesis of bacteriochlorophylls (BChls) and photosynthetic reaction centers were much more abundant at night. Both Roseiflexus spp. and Chloroflexus spp. expressed key genes involved in the 3-hydroxypropionate (3-OHP) carbon dioxide fixation bi-cycle during the day, when these FAPs have been thought to perform primarily photoheterotrophic and/or aerobic chemoorganotrophic metabolism. The expression of genes for the synthesis and degradation of storage polymers, including glycogen, polyhydroxyalkanoates and wax esters, suggests that FAPs produce and utilize these compounds at different times during the diel cycle. We summarize these results in a proposed conceptual model for temporal changes in central carbon metabolism and energy production of FAPs living in a natural environment. The model proposes that, at night, Chloroflexus spp. and Roseiflexus spp. synthesize BChl, components of the photosynthetic apparatus, polyhydroxyalkanoates and wax esters in concert with fermentation of glycogen. It further proposes that, in daytime, polyhydroxyalkanoates and wax esters are degraded and used as carbon and electron reserves to support photomixotrophy via the 3-OHP bi-cycle.
Collapse
Affiliation(s)
- Christian G Klatt
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Skogsmarksgra¨nd, Umea°, Va¨sterbotten SE-90183, Sweden.
| | | | | | | | | | | | | |
Collapse
|
48
|
Adams PG, Cadby AJ, Robinson B, Tsukatani Y, Tank M, Wen J, Blankenship RE, Bryant DA, Hunter CN. Comparison of the physical characteristics of chlorosomes from three different phyla of green phototrophic bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2013; 1827:1235-44. [PMID: 23867748 DOI: 10.1016/j.bbabio.2013.07.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 07/05/2013] [Accepted: 07/08/2013] [Indexed: 11/18/2022]
Abstract
Chlorosomes, the major antenna complexes in green sulphur bacteria, filamentous anoxygenic phototrophs, and phototrophic acidobacteria, are attached to the cytoplasmic side of the inner cell membrane and contain thousands of bacteriochlorophyll (BChl) molecules that harvest light and channel the energy to membrane-bound reaction centres. Chlorosomes from phototrophs representing three different phyla, Chloroflexus (Cfx.) aurantiacus, Chlorobaculum (Cba.) tepidum and the newly discovered "Candidatus (Ca.) Chloracidobacterium (Cab.) thermophilum" were analysed using PeakForce Tapping atomic force microscopy (PFT-AFM). Gentle PFT-AFM imaging in buffered solutions that maintained the chlorosomes in a near-native state revealed ellipsoids of variable size, with surface bumps and undulations that differ between individual chlorosomes. Cba. tepidum chlorosomes were the largest (133×57×36nm; 141,000nm(3) volume), compared with chlorosomes from Cfx. aurantiacus (120×44×30nm; 84,000nm(3)) and Ca. Cab. thermophilum (99×40×31nm; 65,000nm(3)). Reflecting the contributions of thousands of pigment-pigment stacking interactions to the stability of these supramolecular assemblies, analysis by nanomechanical mapping shows that chlorosomes are highly stable and that their integrity is disrupted only by very strong forces of 1000-2000pN. AFM topographs of Ca. Cab. thermophilum chlorosomes that had retained their attachment to the cytoplasmic membrane showed that this membrane dynamically changes shape and is composed of protrusions of up to 30nm wide and 6nm above the mica support, possibly representing different protein domains. Spectral imaging revealed significant heterogeneity in the fluorescence emission of individual chlorosomes, likely reflecting the variations in BChl c homolog composition and internal arrangements of the stacked BChls within each chlorosome.
Collapse
Affiliation(s)
- Peter G Adams
- Department of Molecular Biology and Biotechnology, University of Sheffield, Sheffield S10 2TN, UK
| | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Sousa FL, Shavit-Grievink L, Allen JF, Martin WF. Chlorophyll biosynthesis gene evolution indicates photosystem gene duplication, not photosystem merger, at the origin of oxygenic photosynthesis. Genome Biol Evol 2013; 5:200-16. [PMID: 23258841 PMCID: PMC3595025 DOI: 10.1093/gbe/evs127] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
An open question regarding the evolution of photosynthesis is how cyanobacteria came to possess the two reaction center (RC) types, Type I reaction center (RCI) and Type II reaction center (RCII). The two main competing theories in the foreground of current thinking on this issue are that either 1) RCI and RCII are related via lineage divergence among anoxygenic photosynthetic bacteria and became merged in cyanobacteria via an event of large-scale lateral gene transfer (also called "fusion" theories) or 2) the two RC types are related via gene duplication in an ancestral, anoxygenic but protocyanobacterial phototroph that possessed both RC types before making the transition to using water as an electron donor. To distinguish between these possibilities, we studied the evolution of the core (bacterio)chlorophyll biosynthetic pathway from protoporphyrin IX (Proto IX) up to (bacterio)chlorophyllide a. The results show no dichotomy of chlorophyll biosynthesis genes into RCI- and RCII-specific chlorophyll biosynthetic clades, thereby excluding models of fusion at the origin of cyanobacteria and supporting the selective-loss hypothesis. By considering the cofactor demands of the pathway and the source genes from which several steps in chlorophyll biosynthesis are derived, we infer that the cell that first synthesized chlorophyll was a cobalamin-dependent, heme-synthesizing, diazotrophic anaerobe.
Collapse
Affiliation(s)
- Filipa L Sousa
- Institute of Molecular Evolution, University of Düsseldorf, Düsseldorf, Germany.
| | | | | | | |
Collapse
|
50
|
Klatt CG, Inskeep WP, Herrgard MJ, Jay ZJ, Rusch DB, Tringe SG, Niki Parenteau M, Ward DM, Boomer SM, Bryant DA, Miller SR. Community structure and function of high-temperature chlorophototrophic microbial mats inhabiting diverse geothermal environments. Front Microbiol 2013; 4:106. [PMID: 23761787 PMCID: PMC3669762 DOI: 10.3389/fmicb.2013.00106] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Accepted: 04/13/2013] [Indexed: 11/13/2022] Open
Abstract
Six phototrophic microbial mat communities from different geothermal springs (YNP) were studied using metagenome sequencing and geochemical analyses. The primary goals of this work were to determine differences in community composition of high-temperature phototrophic mats distributed across the Yellowstone geothermal ecosystem, and to identify metabolic attributes of predominant organisms present in these communities that may correlate with environmental attributes important in niche differentiation. Random shotgun metagenome sequences from six phototrophic communities (average ∼53 Mbp/site) were subjected to multiple taxonomic, phylogenetic, and functional analyses. All methods, including G + C content distribution, MEGAN analyses, and oligonucleotide frequency-based clustering, provided strong support for the dominant community members present in each site. Cyanobacteria were only observed in non-sulfidic sites; de novo assemblies were obtained for Synechococcus-like populations at Chocolate Pots (CP_7) and Fischerella-like populations at White Creek (WC_6). Chloroflexi-like sequences (esp. Roseiflexus and/or Chloroflexus spp.) were observed in all six samples and contained genes involved in bacteriochlorophyll biosynthesis and the 3-hydroxypropionate carbon fixation pathway. Other major sequence assemblies were obtained for a Chlorobiales population from CP_7 (proposed family Thermochlorobacteriaceae), and an anoxygenic, sulfur-oxidizing Thermochromatium-like (Gamma-proteobacteria) population from Bath Lake Vista Annex (BLVA_20). Additional sequence coverage is necessary to establish more complete assemblies of other novel bacteria in these sites (e.g., Bacteroidetes and Firmicutes); however, current assemblies suggested that several of these organisms play important roles in heterotrophic and fermentative metabolisms. Definitive linkages were established between several of the dominant phylotypes present in these habitats and important functional processes such as photosynthesis, carbon fixation, sulfur oxidation, and fermentation.
Collapse
Affiliation(s)
- Christian G Klatt
- Department of Land Resources and Environmental Sciences, Montana State University , Bozeman, MT , USA ; Thermal Biology Institute, Montana State University , Bozeman, MT , USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|