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Coker JA. 'All About' Extremophiles. Fac Rev 2023; 12:27. [PMID: 38027090 PMCID: PMC10630985 DOI: 10.12703/r/12-27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023] Open
Abstract
Despite common perception, most of Earth is what is often referred to as an 'extreme environment.' Yet to the organisms that call these places home, it is simply that (home). They have adapted to thrive in these environments and, in the process, have evolved many unique adaptations at the molecular- and 'omic-level. Scientists' interest in these organisms has typically been in how they and their products can be harnessed for biotechnological applications and the environments where they are found, while the general public's veers more toward a fascination with their deviation from the 'norm'. However, these organisms have so much more to tell us about Life and the myriad ways there are to perform 'simple' biological processes.
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Affiliation(s)
- James A Coker
- Center for Biotechnology Education, Advanced Academic Programs, Krieger School of Arts and Sciences, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA
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2
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Prathiviraj R, Chellapandi P. Modeling a global regulatory network of Methanothermobacter thermautotrophicus strain ∆H. ACTA ACUST UNITED AC 2020. [DOI: 10.1007/s13721-020-0223-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Abstract
Despite the typical human notion that the Earth is a habitable planet, over three quarters of our planet is uninhabitable by us without assistance. The organisms that live and thrive in these “inhospitable” environments are known by the name extremophiles and are found in all Domains of Life. Despite our general lack of knowledge about them, they have already assisted humans in many ways and still have much more to give. In this review, I describe how they have adapted to live/thrive/survive in their niches, helped scientists unlock major scientific discoveries, advance the field of biotechnology, and inform us about the boundaries of Life and where we might find it in the Universe.
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Affiliation(s)
- James A Coker
- Department of Sciences, University of Maryland Global Campus, Adelphi, MD, USA
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Li J, Zhang B, Zhou L, Qi L, Yue L, Zhang W, Cheng H, Whitman WB, Dong X. The archaeal RNA chaperone TRAM0076 shapes the transcriptome and optimizes the growth of Methanococcus maripaludis. PLoS Genet 2019; 15:e1008328. [PMID: 31404065 PMCID: PMC6705878 DOI: 10.1371/journal.pgen.1008328] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 08/22/2019] [Accepted: 07/22/2019] [Indexed: 11/27/2022] Open
Abstract
TRAM is a conserved domain among RNA modification proteins that are widely distributed in various organisms. In Archaea, TRAM occurs frequently as a standalone protein with in vitro RNA chaperone activity; however, its biological significance and functional mechanism remain unknown. This work demonstrated that TRAM0076 is an abundant standalone TRAM protein in the genetically tractable methanoarcheaon Methanococcus maripaludis. Deletion of MMP0076, the gene encoding TRAM0076, markedly reduced the growth and altered transcription of 55% of the genome. Substitution mutations of Phe39, Phe42, Phe63, Phe65 and Arg35 in the recombinant TRAM0076 decreased the in vitro duplex RNA unfolding activity. These mutations also prevented complementation of the growth defect of the MMP0076 deletion mutant, indicating that the duplex RNA unfolding activity was essential for its physiological function. A genome-wide mapping of transcription start sites identified many 5' untranslated regions (5'UTRs) of 20-60 nt which could be potential targets of a RNA chaperone. TRAM0076 unfolded three representative 5'UTR structures in vitro and facilitated the in vivo expression of a mCherry reporter system fused to the 5'UTRs, thus behaving like a transcription anti-terminator. Flag-tagged-TRAM0076 co-immunoprecipitated a large number of cellular RNAs, suggesting that TRAM0076 plays multiple roles in addition to unfolding incorrect RNA structures. This work demonstrates that the conserved archaeal RNA chaperone TRAM globally affects gene expression and may represent a transcriptional element in ancient life of the RNA world.
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Affiliation(s)
- Jie Li
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, PR China
| | - Bo Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, PR China
- University of Chinese Academy of Sciences, Shijingshan District, Beijing, China
| | - Liguang Zhou
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, PR China
- University of Chinese Academy of Sciences, Shijingshan District, Beijing, China
| | - Lei Qi
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, PR China
| | - Lei Yue
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, PR China
- University of Chinese Academy of Sciences, Shijingshan District, Beijing, China
| | - Wenting Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, PR China
- University of Chinese Academy of Sciences, Shijingshan District, Beijing, China
| | - Huicai Cheng
- Biology Institute, Hebei Academy of Sciences, Shijiazhuang, China
| | - William B. Whitman
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - Xiuzhu Dong
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, PR China
- University of Chinese Academy of Sciences, Shijingshan District, Beijing, China
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5
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Martinez-Pastor M, Tonner PD, Darnell CL, Schmid AK. Transcriptional Regulation in Archaea: From Individual Genes to Global Regulatory Networks. Annu Rev Genet 2018; 51:143-170. [PMID: 29178818 DOI: 10.1146/annurev-genet-120116-023413] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Archaea are major contributors to biogeochemical cycles, possess unique metabolic capabilities, and resist extreme stress. To regulate the expression of genes encoding these unique programs, archaeal cells use gene regulatory networks (GRNs) composed of transcription factor proteins and their target genes. Recent developments in genetics, genomics, and computational methods used with archaeal model organisms have enabled the mapping and prediction of global GRN structures. Experimental tests of these predictions have revealed the dynamical function of GRNs in response to environmental variation. Here, we review recent progress made in this area, from investigating the mechanisms of transcriptional regulation of individual genes to small-scale subnetworks and genome-wide global networks. At each level, archaeal GRNs consist of a hybrid of bacterial, eukaryotic, and uniquely archaeal mechanisms. We discuss this theme from the perspective of the role of individual transcription factors in genome-wide regulation, how these proteins interact to compile GRN topological structures, and how these topologies lead to emergent, high-level GRN functions. We conclude by discussing how systems biology approaches are a fruitful avenue for addressing remaining challenges, such as discovering gene function and the evolution of GRNs.
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Affiliation(s)
| | - Peter D Tonner
- Department of Biology, Duke University, Durham, North Carolina 27708, USA.,Graduate Program in Computational Biology and Bioinformatics, Duke University, Durham, North Carolina 27708, USA
| | - Cynthia L Darnell
- Department of Biology, Duke University, Durham, North Carolina 27708, USA
| | - Amy K Schmid
- Department of Biology, Duke University, Durham, North Carolina 27708, USA.,Graduate Program in Computational Biology and Bioinformatics, Duke University, Durham, North Carolina 27708, USA.,Center for Genomic and Computational Biology, Duke University, Durham, North Carolina 27708, USA;
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6
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Blombach F, Grohmann D. Same same but different: The evolution of TBP in archaea and their eukaryotic offspring. Transcription 2017; 8:162-168. [PMID: 28340330 PMCID: PMC5501381 DOI: 10.1080/21541264.2017.1289879] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Transcription factors TBP and TF(II)B assemble with RNA polymerase at the promoter DNA forming the initiation complex. Despite a high degree of conservation, the molecular binding mechanisms of archaeal and eukaryotic TBP and TF(II)B differ significantly. Based on recent biophysical data, we speculate how the mechanisms co-evolved with transcription regulation and TBP multiplicity.
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Affiliation(s)
- Fabian Blombach
- a RNAP Laboratory , University College London, Institute of Structural and Molecular Biology, Division of Biosciences , London , UK
| | - Dina Grohmann
- b Department of Biochemistry, Genetics and Microbiology , Institute of Microbiology, University of Regensburg , Regensburg , Germany
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Peterson JR, Thor S, Kohler L, Kohler PR, Metcalf WW, Luthey-Schulten Z. Genome-wide gene expression and RNA half-life measurements allow predictions of regulation and metabolic behavior in Methanosarcina acetivorans. BMC Genomics 2016; 17:924. [PMID: 27852217 PMCID: PMC5112694 DOI: 10.1186/s12864-016-3219-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 10/26/2016] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND While a few studies on the variations in mRNA expression and half-lives measured under different growth conditions have been used to predict patterns of regulation in bacterial organisms, the extent to which this information can also play a role in defining metabolic phenotypes has yet to be examined systematically. Here we present the first comprehensive study for a model methanogen. RESULTS We use expression and half-life data for the methanogen Methanosarcina acetivorans growing on fast- and slow-growth substrates to examine the regulation of its genes. Unlike Escherichia coli where only small shifts in half-lives were observed, we found that most mRNA have significantly longer half-lives for slow growth on acetate compared to fast growth on methanol or trimethylamine. Interestingly, half-life shifts are not uniform across functional classes of enzymes, suggesting the existence of a selective stabilization mechanism for mRNAs. Using the transcriptomics data we determined whether transcription or degradation rate controls the change in transcript abundance. Degradation was found to control abundance for about half of the metabolic genes underscoring its role in regulating metabolism. Genes involved in half of the metabolic reactions were found to be differentially expressed among the substrates suggesting the existence of drastically different metabolic phenotypes that extend beyond just the methanogenesis pathways. By integrating expression data with an updated metabolic model of the organism (iST807) significant differences in pathway flux and production of metabolites were predicted for the three growth substrates. CONCLUSIONS This study provides the first global picture of differential expression and half-lives for a class II methanogen, as well as provides the first evidence in a single organism that drastic genome-wide shifts in RNA half-lives can be modulated by growth substrate. We determined which genes in each metabolic pathway control the flux and classified them as regulated by transcription (e.g. transcription factor) or degradation (e.g. post-transcriptional modification). We found that more than half of genes in metabolism were controlled by degradation. Our results suggest that M. acetivorans employs extensive post-transcriptional regulation to optimize key metabolic steps, and more generally that degradation could play a much greater role in optimizing an organism's metabolism than previously thought.
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Affiliation(s)
- Joseph R. Peterson
- Department of Chemistry, University of Illinois at Urbana-Champaign, 505 S Mathews Ave, Urbana, 60801 IL USA
| | - ShengShee Thor
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 1110 W Green St, Urbana, 60801 IL USA
| | - Lars Kohler
- Department of Chemistry, University of Illinois at Urbana-Champaign, 505 S Mathews Ave, Urbana, 60801 IL USA
| | - Petra R.A. Kohler
- Department of Microbiology, University of Illinois at Urbana-Champaign, 601 S Goodwin AveIL, Urbana, 60801 USA
| | - William W. Metcalf
- Department of Microbiology, University of Illinois at Urbana-Champaign, 601 S Goodwin AveIL, Urbana, 60801 USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 W Gregory DrIL, Urbana, 60801 USA
| | - Zaida Luthey-Schulten
- Department of Chemistry, University of Illinois at Urbana-Champaign, 505 S Mathews Ave, Urbana, 60801 IL USA
- Center for Biophysics and Computational Biology, University of Illinois at Urbana-Champaign, 1110 W Green St, Urbana, 60801 IL USA
- Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 W Gregory DrIL, Urbana, 60801 USA
- Beckman Institute, University of Illinois at Urbana-Champaign, 405 N Mathews Ave, Urbana, 60801 IL USA
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Abstract
The known diversity of metabolic strategies and physiological adaptations of archaeal species to extreme environments is extraordinary. Accurate and responsive mechanisms to ensure that gene expression patterns match the needs of the cell necessitate regulatory strategies that control the activities and output of the archaeal transcription apparatus. Archaea are reliant on a single RNA polymerase for all transcription, and many of the known regulatory mechanisms employed for archaeal transcription mimic strategies also employed for eukaryotic and bacterial species. Novel mechanisms of transcription regulation have become apparent by increasingly sophisticated in vivo and in vitro investigations of archaeal species. This review emphasizes recent progress in understanding archaeal transcription regulatory mechanisms and highlights insights gained from studies of the influence of archaeal chromatin on transcription.
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Rodríguez-Lima O, García-Gutierrez P, Jiménez L, Zarain-Herzberg Á, Lazzarini R, Landa A. Molecular Cloning of a cDNA Encoding for Taenia solium TATA-Box Binding Protein 1 (TsTBP1) and Study of Its Interactions with the TATA-Box of Actin 5 and Typical 2-Cys Peroxiredoxin Genes. PLoS One 2015; 10:e0141818. [PMID: 26529408 PMCID: PMC4631506 DOI: 10.1371/journal.pone.0141818] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 10/13/2015] [Indexed: 11/18/2022] Open
Abstract
TATA-box binding protein (TBP) is an essential regulatory transcription factor for the TATA-box and TATA-box-less gene promoters. We report the cloning and characterization of a full-length cDNA that encodes a Taenia solium TATA-box binding protein 1 (TsTBP1). Deduced amino acid composition from its nucleotide sequence revealed that encodes a protein of 238 residues with a predicted molecular weight of 26.7 kDa, and a theoretical pI of 10.6. The NH2-terminal domain shows no conservation when compared with to pig and human TBP1s. However, it shows high conservation in size and amino acid identity with taeniids TBP1s. In contrast, the TsTBP1 COOH-terminal domain is highly conserved among organisms, and contains the amino acids involved in interactions with the TATA-box, as well as with TFIIA and TFIIB. In silico TsTBP1 modeling reveals that the COOH-terminal domain forms the classical saddle structure of the TBP family, with one α-helix at the end, not present in pig and human. Native TsTBP1 was detected in T. solium cysticerci´s nuclear extract by western blot using rabbit antibodies generated against two synthetic peptides located in the NH2 and COOH-terminal domains of TsTBP1. These antibodies, through immunofluorescence technique, identified the TBP1 in the nucleus of cells that form the bladder wall of cysticerci of Taenia crassiceps, an organism close related to T. solium. Electrophoretic mobility shift assays using nuclear extracts from T. solium cysticerci and antibodies against the NH2-terminal domain of TsTBP1 showed the interaction of native TsTBP1 with the TATA-box present in T. solium actin 5 (pAT5) and 2-Cys peroxiredoxin (Ts2-CysPrx) gene promoters; in contrast, when antibodies against the anti-COOH-terminal domain of TsTBP1 were used, they inhibited the binding of TsTBP1 to the TATA-box of the pAT5 promoter gene.
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Affiliation(s)
- Oscar Rodríguez-Lima
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, México D.F., México
| | | | - Lucía Jiménez
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, México D.F., México
| | - Ángel Zarain-Herzberg
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, México D.F., México
| | - Roberto Lazzarini
- Departamento de Biología Experimental, Universidad Autónoma Metropolitana–Iztapalapa, México D.F., México
| | - Abraham Landa
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, México D.F., México
- * E-mail:
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Phylogenetically driven sequencing of extremely halophilic archaea reveals strategies for static and dynamic osmo-response. PLoS Genet 2014; 10:e1004784. [PMID: 25393412 PMCID: PMC4230888 DOI: 10.1371/journal.pgen.1004784] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 09/29/2014] [Indexed: 12/19/2022] Open
Abstract
Organisms across the tree of life use a variety of mechanisms to respond to stress-inducing fluctuations in osmotic conditions. Cellular response mechanisms and phenotypes associated with osmoadaptation also play important roles in bacterial virulence, human health, agricultural production and many other biological systems. To improve understanding of osmoadaptive strategies, we have generated 59 high-quality draft genomes for the haloarchaea (a euryarchaeal clade whose members thrive in hypersaline environments and routinely experience drastic changes in environmental salinity) and analyzed these new genomes in combination with those from 21 previously sequenced haloarchaeal isolates. We propose a generalized model for haloarchaeal management of cytoplasmic osmolarity in response to osmotic shifts, where potassium accumulation and sodium expulsion during osmotic upshock are accomplished via secondary transport using the proton gradient as an energy source, and potassium loss during downshock is via a combination of secondary transport and non-specific ion loss through mechanosensitive channels. We also propose new mechanisms for magnesium and chloride accumulation. We describe the expansion and differentiation of haloarchaeal general transcription factor families, including two novel expansions of the TATA-binding protein family, and discuss their potential for enabling rapid adaptation to environmental fluxes. We challenge a recent high-profile proposal regarding the evolutionary origins of the haloarchaea by showing that inclusion of additional genomes significantly reduces support for a proposed large-scale horizontal gene transfer into the ancestral haloarchaeon from the bacterial domain. The combination of broad (17 genera) and deep (≥5 species in four genera) sampling of a phenotypically unified clade has enabled us to uncover both highly conserved and specialized features of osmoadaptation. Finally, we demonstrate the broad utility of such datasets, for metagenomics, improvements to automated gene annotation and investigations of evolutionary processes. The ability to adjust to changing osmotic conditions (osmoadaptation) is crucial to the survival of organisms across the tree of life. However, significant gaps still exist in our understanding of this important phenomenon. To help fill some of these gaps, we have produced high-quality draft genomes for 59 osmoadaptation “experts” (extreme halophiles of the euryarchaeal family Halobacteriaceae). We describe the dispersal of osmoadaptive protein families across the haloarchaeal evolutionary tree. We use this data to suggest a generalized model for haloarchaeal ion transport in response to changing osmotic conditions, including proposed new mechanisms for magnesium and chloride accumulation. We describe the evolutionary expansion and differentiation of haloarchaeal general transcription factor families and discuss their potential for enabling rapid adaptation to environmental fluxes. Lastly, we challenge a recent high-profile proposal regarding the evolutionary origins of the haloarchaea by showing that inclusion of additional genomes significantly reduces support for a proposed large-scale horizontal gene transfer into the ancestral haloarchaeon from the bacterial domain. This result highlights the power of our dataset for making evolutionary inferences, a feature which will make it useful to the broader evolutionary community. We distribute our genomic dataset through a user-friendly graphical interface.
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Different roles of two transcription factor B proteins in the hyperthermophilic archaeon Thermococcus kodakarensis. Extremophiles 2014; 18:573-88. [DOI: 10.1007/s00792-014-0638-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 03/03/2014] [Indexed: 11/26/2022]
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Towards a computational model of a methane producing archaeum. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2014; 2014:898453. [PMID: 24729742 PMCID: PMC3960522 DOI: 10.1155/2014/898453] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 12/18/2013] [Indexed: 11/17/2022]
Abstract
Progress towards a complete model of the methanogenic archaeum Methanosarcina acetivorans is reported. We characterized size distribution of the cells using differential interference contrast microscopy, finding them to be ellipsoidal with mean length and width of 2.9 μm and 2.3 μm, respectively, when grown on methanol and 30% smaller when grown on acetate. We used the single molecule pull down (SiMPull) technique to measure average copy number of the Mcr complex and ribosomes. A kinetic model for the methanogenesis pathways based on biochemical studies and recent metabolic reconstructions for several related methanogens is presented. In this model, 26 reactions in the methanogenesis pathways are coupled to a cell mass production reaction that updates enzyme concentrations. RNA expression data (RNA-seq) measured for cell cultures grown on acetate and methanol is used to estimate relative protein production per mole of ATP consumed. The model captures the experimentally observed methane production rates for cells growing on methanol and is most sensitive to the number of methyl-coenzyme-M reductase (Mcr) and methyl-tetrahydromethanopterin:coenzyme-M methyltransferase (Mtr) proteins. A draft transcriptional regulation network based on known interactions is proposed which we intend to integrate with the kinetic model to allow dynamic regulation.
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13
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Grohmann D, Werner F. Recent advances in the understanding of archaeal transcription. Curr Opin Microbiol 2011; 14:328-34. [DOI: 10.1016/j.mib.2011.04.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 04/13/2011] [Accepted: 04/13/2011] [Indexed: 01/12/2023]
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Ferry JG. Fundamentals of methanogenic pathways that are key to the biomethanation of complex biomass. Curr Opin Biotechnol 2011; 22:351-7. [PMID: 21555213 DOI: 10.1016/j.copbio.2011.04.011] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Accepted: 04/18/2011] [Indexed: 12/17/2022]
Abstract
The conversion of biomass to CH4 (biomethanation) involves an anaerobic microbial food chain composed of at least three metabolic groups of which the first two decompose the complex biomass primarily to acetate, formate, and H2. The thermodynamics of these conversions are unfavorable requiring a symbiosis with the CH4-producing group (methanogens) that metabolize the decomposition products to favorable concentrations. The methanogens produce CH4 by two major pathways, conversion of the methyl group of acetate and reduction of CO2 coupled to the oxidation of formate or H2. This review covers recent advances in the fundamental understanding of both methanogenic pathways with the view of stimulating research towards improving the rate and reliability of the overall biomethanation process.
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Affiliation(s)
- James G Ferry
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16801, United States.
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15
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Jun SH, Reichlen MJ, Tajiri M, Murakami KS. Archaeal RNA polymerase and transcription regulation. Crit Rev Biochem Mol Biol 2011; 46:27-40. [PMID: 21250781 DOI: 10.3109/10409238.2010.538662] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
To elucidate the mechanism of transcription by cellular RNA polymerases (RNAPs), high-resolution X-ray crystal structures together with structure-guided biochemical, biophysical, and genetics studies are essential. The recently solved X-ray crystal structures of archaeal RNAP allow a structural comparison of the transcription machinery among all three domains of life. The archaea were once thought of closely related to bacteria, but they are now considered to be more closely related to the eukaryote at the molecular level than bacteria. According to these structures, the archaeal transcription apparatus, which includes RNAP and general transcription factors (GTFs), is similar to the eukaryotic transcription machinery. Yet, the transcription regulators, activators and repressors, encoded by archaeal genomes are closely related to bacterial factors. Therefore, archaeal transcription appears to possess an intriguing hybrid of eukaryotic-type transcription apparatus and bacterial-like regulatory mechanisms. Elucidating the transcription mechanism in archaea, which possesses a combination of bacterial and eukaryotic transcription mechanisms that are commonly regarded as separate and mutually exclusive, can provide data that will bring basic transcription mechanisms across all life forms.
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Affiliation(s)
- Sung-Hoon Jun
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
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An engineered methanogenic pathway derived from the domains Bacteria and Archaea. mBio 2010; 1. [PMID: 21060738 PMCID: PMC2975365 DOI: 10.1128/mbio.00243-10] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Accepted: 10/05/2010] [Indexed: 01/09/2023] Open
Abstract
A plasmid-based expression system wherein mekB was fused to a constitutive Methanosarcina acetivorans promoter was used to express MekB, a broad-specificity esterase from Pseudomonas veronii, in M. acetivorans. The engineered strain had 80-fold greater esterase activity than wild-type M. acetivorans. Methyl acetate and methyl propionate esters served as the sole carbon and energy sources, resulting in robust growth and methane formation, with consumption of >97% of the substrates. Methanol was undetectable at the end of growth with methyl acetate, whereas acetate accumulated, a result consistent with methanol as the more favorable substrate. Acetate was consumed, and growth continued after a period of adaptation. Similar results were obtained with methyl propionate, except propionate was not metabolized.
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17
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Hot Transcriptomics. ARCHAEA 2010; 2010:897585. [PMID: 21350598 PMCID: PMC3038420 DOI: 10.1155/2010/897585] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 11/19/2010] [Accepted: 12/20/2010] [Indexed: 12/14/2022]
Abstract
DNA microarray technology allows for a quick and easy comparison of complete transcriptomes, resulting in improved molecular insight in fluctuations of gene expression. After emergence of the microarray technology about a decade ago, the technique has now matured and has become routine in many molecular biology laboratories. Numerous studies have been performed that have provided global transcription patterns of many organisms under a wide range of conditions. Initially, implementation of this high-throughput technology has lead to high expectations for ground breaking discoveries. Here an evaluation is performed of the insight that transcriptome analysis has brought about in the field of hyperthermophilic archaea. The examples that will be discussed have been selected on the basis of their impact, in terms of either biological insight or technological progress.
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