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Grünberger F, Schmid G, El Ahmad Z, Fenk M, Vogl K, Reichelt R, Hausner W, Urlaub H, Lenz C, Grohmann D. Uncovering the temporal dynamics and regulatory networks of thermal stress response in a hyperthermophile using transcriptomics and proteomics. mBio 2023; 14:e0217423. [PMID: 37843364 PMCID: PMC10746257 DOI: 10.1128/mbio.02174-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Accepted: 08/30/2023] [Indexed: 10/17/2023] Open
Abstract
IMPORTANCE Extreme environments provide unique challenges for life, and the study of extremophiles can shed light on the mechanisms of adaptation to such conditions. Pyrococcus furiosus, a hyperthermophilic archaeon, is a model organism for studying thermal stress response mechanisms. In this study, we used an integrated analysis of RNA-sequencing and mass spectrometry data to investigate the transcriptomic and proteomic responses of P. furiosus to heat and cold shock stress and recovery. Our results reveal the rapid and dynamic changes in gene and protein expression patterns associated with these stress responses, as well as the coordinated regulation of different gene sets in response to different stressors. These findings provide valuable insights into the molecular adaptations that facilitate life in extreme environments and advance our understanding of stress response mechanisms in hyperthermophilic archaea.
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Affiliation(s)
- Felix Grünberger
- Institute of Biochemistry, Genetics and Microbiology, Institute of Microbiology and Archaea Centre, Single-Molecule Biochemistry Lab and Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Georg Schmid
- Institute of Biochemistry, Genetics and Microbiology, Institute of Microbiology and Archaea Centre, Single-Molecule Biochemistry Lab and Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Zubeir El Ahmad
- Institute of Biochemistry, Genetics and Microbiology, Institute of Microbiology and Archaea Centre, Single-Molecule Biochemistry Lab and Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Martin Fenk
- Institute of Biochemistry, Genetics and Microbiology, Institute of Microbiology and Archaea Centre, Single-Molecule Biochemistry Lab and Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Katharina Vogl
- Institute of Biochemistry, Genetics and Microbiology, Institute of Microbiology and Archaea Centre, Single-Molecule Biochemistry Lab and Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Robert Reichelt
- Institute of Biochemistry, Genetics and Microbiology, Institute of Microbiology and Archaea Centre, Single-Molecule Biochemistry Lab and Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Winfried Hausner
- Institute of Biochemistry, Genetics and Microbiology, Institute of Microbiology and Archaea Centre, Single-Molecule Biochemistry Lab and Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Department of Clinical Chemistry, University Medical Center Göttingen, Göttingen, Germany
| | - Christof Lenz
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
- Department of Clinical Chemistry, University Medical Center Göttingen, Göttingen, Germany
| | - Dina Grohmann
- Institute of Biochemistry, Genetics and Microbiology, Institute of Microbiology and Archaea Centre, Single-Molecule Biochemistry Lab and Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
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An alternative resource allocation strategy in the chemolithoautotrophic archaeon Methanococcus maripaludis. Proc Natl Acad Sci U S A 2021; 118:2025854118. [PMID: 33879571 DOI: 10.1073/pnas.2025854118] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Most microorganisms in nature spend the majority of time in a state of slow or zero growth and slow metabolism under limited energy or nutrient flux rather than growing at maximum rates. Yet, most of our knowledge has been derived from studies on fast-growing bacteria. Here, we systematically characterized the physiology of the methanogenic archaeon Methanococcus maripaludis during slow growth. M. maripaludis was grown in continuous culture under energy (formate)-limiting conditions at different dilution rates ranging from 0.09 to 0.002 h-1, the latter corresponding to 1% of its maximum growth rate under laboratory conditions (0.23 h-1). While the specific rate of methanogenesis correlated with growth rate as expected, the fraction of cellular energy used for maintenance increased and the maintenance energy per biomass decreased at slower growth. Notably, proteome allocation between catabolic and anabolic pathways was invariant with growth rate. Unexpectedly, cells maintained their maximum methanogenesis capacity over a wide range of growth rates, except for the lowest rates tested. Cell size, cellular DNA, RNA, and protein content as well as ribosome numbers also were largely invariant with growth rate. A reduced protein synthesis rate during slow growth was achieved by a reduction in ribosome activity rather than via the number of cellular ribosomes. Our data revealed a resource allocation strategy of a methanogenic archaeon during energy limitation that is fundamentally different from commonly studied versatile chemoheterotrophic bacteria such as E. coli.
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Shiimori M, Garrett SC, Chambers DP, Glover CVC, Graveley BR, Terns MP. Role of free DNA ends and protospacer adjacent motifs for CRISPR DNA uptake in Pyrococcus furiosus. Nucleic Acids Res 2017; 45:11281-11294. [PMID: 29036456 PMCID: PMC5737086 DOI: 10.1093/nar/gkx839] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/12/2017] [Indexed: 02/06/2023] Open
Abstract
To acquire CRISPR–Cas immunity against invasive mobile genetic elements, prokaryotes must first integrate fragments of foreign DNA into their genomic CRISPR arrays for use in future invader silencing. Here, we found that the hyperthermophilic archaeaon, Pyrococcus furiosus, actively incorporates DNA fragments (spacers) from both plasmid (foreign) and host genome (self) sequences into its seven CRISPR loci. The majority of new spacers were derived from DNA immediately downstream from a 5′-CCN-3′ protospacer adjacent motif (PAM) that is critical for invader targeting. Interestingly, spacers were preferentially acquired from genome or plasmid regions corresponding to active transposons, CRISPR loci, ribosomal RNA genes, rolling circle origins of replication, and areas where plasmids recombined with the host chromosome. A common feature of the highly sampled spacers is that they arise from DNA regions expected to undergo DNA nicking and/or double-strand breaks. Taken together with recent results from bacterial systems, our findings indicate that free DNA termini and PAMs are conserved features important for CRISPR spacer uptake in diverse prokaryotes and CRISPR–Cas systems. Moreover, lethal self-targeting by CRISPR systems may contribute to host genome stability by eliminating cells undergoing active transposon mobility or chromosomal uptake of autonomously replicating foreign mobile genetic elements.
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Affiliation(s)
- Masami Shiimori
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Sandra C Garrett
- Department of Genetics and Genome Sciences, Institute for Systems Genomics, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Dwain P Chambers
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Claiborne V C Glover
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA
| | - Brenton R Graveley
- Department of Genetics and Genome Sciences, Institute for Systems Genomics, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Michael P Terns
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA 30602, USA.,Department of Genetics, University of Georgia, Athens, GA 30602, USA.,Department of Microbiology, University of Georgia, Athens, GA 30602, USA
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Global responses of Methanococcus maripaludis to specific nutrient limitations and growth rate. J Bacteriol 2008; 190:2198-205. [PMID: 18203827 DOI: 10.1128/jb.01805-07] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Continuous culture, transcriptome arrays, and measurements of cellular amino acid pools and tRNA charging levels were used to determine the response of Methanococcus maripaludis to leucine limitation. For comparison, the responses to phosphate and H2 limitations were measured as well. In addition, the effect of growth rate was determined. Leucine limitation resulted in a broad response. tRNA(Leu) charging decreased, but only small increases in mRNA were seen for amino acid biosynthesis genes. However, the cellular levels of free isoleucine and valine showed significant increases, indicating a coordinate regulation of branched-chain amino acids at a post-mRNA level. Leucine limitation also resulted in increased mRNA abundance for ribosomal protein genes, increased rRNA abundance, and decreased mRNA abundance for genes of methanogenesis. In contrast, phosphate limitation induced a specific response, a marked increase in mRNA levels for a phosphate transporter. Some mRNA levels responded to more than one factor; for example, transcripts for flagellum synthesis genes decreased under conditions of leucine limitation and increased under H2 limitation. Increased growth rate resulted in increased mRNA levels for ribosomal protein genes, increased rRNA abundance, and increased mRNA for a gene encoding an S-layer protein.
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Archaeal transcription: function of an alternative transcription factor B from Pyrococcus furiosus. J Bacteriol 2007; 190:157-67. [PMID: 17965161 DOI: 10.1128/jb.01498-07] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The genome of the hyperthermophile archaeon Pyrococcus furiosus encodes two transcription factor B (TFB) paralogs, one of which (TFB1) was previously characterized in transcription initiation. The second TFB (TFB2) is unusual in that it lacks recognizable homology to the archaeal TFB/eukaryotic TFIIB B-finger motif. TFB2 functions poorly in promoter-dependent transcription initiation, but photochemical cross-linking experiments indicated that the orientation and occupancy of transcription complexes formed with TFB2 at the strong gdh promoter are similar to the orientation and occupancy of transcription complexes formed with TFB1. Initiation complexes formed by TFB2 display a promoter opening defect that can be bypassed with a preformed transcription bubble, suggesting a mechanism to explain the low TFB2 transcription activity. Domain swaps between TFB1 and TFB2 showed that the low activity of TFB2 is determined mainly by its N terminus. The low activity of TFB2 in promoter opening and transcription can be partially relieved by transcription factor E (TFE). The results indicate that the TFB N-terminal region, containing conserved Zn ribbon and B-finger motifs, is important in promoter opening and that TFE can compensate for defects in the N terminus through enhancement of promoter opening.
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Bartlett MS. Determinants of transcription initiation by archaeal RNA polymerase. Curr Opin Microbiol 2005; 8:677-84. [PMID: 16249119 DOI: 10.1016/j.mib.2005.10.016] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2005] [Accepted: 10/13/2005] [Indexed: 12/27/2022]
Abstract
Transcription in Archaea is catalyzed by an RNA polymerase that is most similar to eukaryotic RNA polymerases both in subunit composition and in transcription initiation factor requirements. Recent studies on archaeal transcription in diverse members of this domain have contributed new details concerning the functions of promoters and transcription factors in guiding initiation by RNA polymerase, and phylogenetic arguments have allowed modeling of archaeal transcription initiation complexes by comparison with recently described models of eukaryotic and bacterial transcription initiation complexes. Important new advances in reconstitution of archaeal transcription complexes from fully recombinant components is permitting testing of hypotheses derived from and informed by these structural models, and will help bring the study of archaeal transcription to the levels of understanding currently enjoyed by bacterial and eukaryotic RNA polymerase II transcription.
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Affiliation(s)
- Michael S Bartlett
- Department of Biology, Portland State University, SB2 Room 246, 1719 SW 10th Avenue, Portland, OR 97201, USA.
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Kaper T, Verhees CH, Lebbink JH, van Lieshout JF, Kluskens LD, Ward DE, Kengen SW, Beerthuyzen MM, de Vos WM, van der Oost J. Characterization of beta-glycosylhydrolases from Pyrococcus furiosus. Methods Enzymol 2001; 330:329-46. [PMID: 11210512 DOI: 10.1016/s0076-6879(01)30386-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- T Kaper
- Laboratory of Microbiology, Wageningen Agricultural University, Wageningen, NL-6703 CT, The Netherlands
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Ward DE, Kengen SW, van Der Oost J, de Vos WM. Purification and characterization of the alanine aminotransferase from the hyperthermophilic Archaeon pyrococcus furiosus and its role in alanine production. J Bacteriol 2000; 182:2559-66. [PMID: 10762259 PMCID: PMC111321 DOI: 10.1128/jb.182.9.2559-2566.2000] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Alanine aminotransferase (AlaAT) was purified from cell extracts of the hyperthermophilic archaeon Pyrococcus furiosus by multistep chromatography. The enzyme has an apparent molecular mass of 93.5 kDa, as estimated by gel filtration, and consists of two identical subunits of 46 kDa, as deduced by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and the gene sequence. The AlaAT displayed a broader substrate specificity than AlaATs from eukaryal sources and exhibited significant activity with alanine, glutamate, and aspartate with either 2-oxoglutarate or pyruvate as the amino acceptor. Optimal activity was found in the pH range of 6. 5 to 7.8 and at a temperature of over 95 degrees C. The N-terminal amino acid sequence of the purified AlaAT was determined and enabled the identification of the gene encoding AlaAT (aat) in the P. furiosus genome database. The gene was expressed in Escherichia coli, and the recombinant enzyme was purified. The pH and temperature dependence, molecular mass, and kinetic parameters of the recombinant were indistinguishable from those of the native enzyme from P. furiosus. The k(cat)/K(m) values for alanine and pyruvate formation were 41 and 33 s(-1) mM(-1), respectively, suggesting that the enzyme is not biased toward either the formation of pyruvate, or alanine. Northern analysis identified a single 1.2-kb transcript for the aat gene. In addition, both the aat and gdh (encoding the glutamate dehydrogenase) transcripts appear to be coregulated at the transcriptional level, because the expression of both genes was induced when the cells were grown on pyruvate. The coordinated control found for the aat and gdh genes is in good agreement with these enzymes acting in a concerted manner to form an electron sink in P. furiosus.
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Affiliation(s)
- D E Ward
- Laboratory of Microbiology, Wageningen Agricultural University, NL-6703 CT Wageningen, The Netherlands.
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van der Oost J, Ciaramella M, Moracci M, Pisani FM, Rossi M, de Vos WM. Molecular biology of hyperthermophilic Archaea. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 1998; 61:87-115. [PMID: 9670798 DOI: 10.1007/bfb0102290] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The sequences of a number of archaeal genomes have recently been completed, and many more are expected shortly. Consequently, the research of Archaea in general and hyperthermophiles in particular has entered a new phase, with many exciting discoveries to be expected. The wealth of sequence information has already led, and will continue to lead to the identification of many enzymes with unique properties, some of which have potential for industrial applications. Subsequent functional genomics will help reveal fundamental matters such as details concerning the genetic, biochemical and physiological adaptation of extremophiles, and hence give insight into their genomic evolution, polypeptide structure-function relations, and metabolic regulation. In order to optimally exploit many unique features that are now emerging, the development of genetic systems for hyperthermophilic Archaea is an absolute requirement. Such systems would allow the application of this class of Archaea as so-called "cell factories": (i) expression of certain archaeal enzymes for which no suitable conventional (mesophilic bacterial or eukaryal) systems are available, (ii) selection for thermostable variants of potentially interesting enzymes from mesophilic origin, and (iii) the development of in vivo production systems by metabolic engineering. An overview is given of recent insight in the molecular biology of hyperthermophilic Archaea, as well as of a number of promising developments that should result in the generation of suitable genetic systems in the near future.
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Affiliation(s)
- J van der Oost
- Department of Microbiology, Wageningen Agricultural University, The Netherlands
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Nomura N, Sako Y, Uchida A. Molecular characterization and postsplicing fate of three introns within the single rRNA operon of the hyperthermophilic archaeon Aeropyrum pernix K1. J Bacteriol 1998; 180:3635-43. [PMID: 9658008 PMCID: PMC107333 DOI: 10.1128/jb.180.14.3635-3643.1998] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The single rRNA operon (arnS-arnL) of the hyperthermophilic archaeon Aeropyrum pernix K1 was sequenced. The DNA sequence data and detailed RNA analyses disclosed an unusual feature: the presence of three introns at hitherto undescribed insertion positions within the rRNA genes. The 699-nucleotide (nt) intron Ialpha was located at position 908 (Escherichia coli numbering [H. F. Noller, Annu. Rev. Biochem. 53:119-162, 1984]) of the 16S rRNA, while the 202-nt intron Ibeta and 575-nt intron Igamma were located at positions 1085 and 1927 (E. coli numbering), respectively, of the 23S rRNA. They were located within highly conserved sites which have been implicated as crucial for rRNA function in E. coli. All three introns were remarkably AT rich (41.5 to 43.1 mol% G+C) compared with the mature rRNAs (67.7 and 69.2 mol% G+C for 16S and 23S rRNAs, respectively). No obvious primary sequence similarities were detected among them. After splicing from rRNA transcripts in vivo, a large quantity of intronic RNAs were stably retained in the linear monomeric form, whereas a trace of topoisomeric RNA molecules also appeared, as characterized by their behavior in two-dimensional gel electrophoresis. Secondary structural models of the Ialpha-, Ibeta-, and Igamma-containing rRNA precursors agree with the bulge-helix-bulge motif. Two of the introns, Ialpha and Igamma, contained open reading frames whose protein translation exhibited no overall similarity with proteins reported so far. However, both share a LAGLI-DADG motif characteristic of homing endonucleases.
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Affiliation(s)
- N Nomura
- Laboratory of Marine Microbiology, Division of Applied Bioscience, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502,
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Aagaard C, Leviev I, Aravalli RN, Forterre P, Prieur D, Garrett RA. General vectors for archaeal hyperthermophiles: strategies based on a mobile intron and a plasmid. FEMS Microbiol Rev 1996; 18:93-104. [PMID: 8639332 DOI: 10.1111/j.1574-6976.1996.tb00229.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Although there are currently no cloning and expression vectors available for archaeal hyperthermophiles, small cryptic plasmids have been characterized for these organisms as well as viruses and introns capable of spreading between cells. Below, we review the recent progress in adapting these genetic elements as vectors for Pyrococcus furiosus and Sulfolobus acidocaldarius. An efficient and reliable transformation procedure is described for both organisms. The potential of the mobile intron from Desulfurococcus mobilis, inserted into the bacterial vector pUC18 to generate a new type of vector, was investigated in S. acidocaldarius. A polylinker was inserted upstream from the open reading frame encoding the homing enzyme I-DmoI. Both the polylinker and a 276 bp fragment of the tetracycline gene from pBR322 could be inserted into the intron-plasmid construct and spreading still occurred in the culture of S. acidocaldarius. Experiments are in progress to test the co-mobility of the alcohol dehydrogenase and beta-galactosidase genes from Sulfolobus species with the intron. A shuttle vector pCSV1 was also produced by fusing the pGT5 plasmid from Pyrococcus abyssi and the bacterial vector pUC19 which, on transformation, is stable in both organisms without selection. Growth inhibition studies indicate that both P. furiosus and S. acidocaldarius are sensitive to the antibiotics carbomycin, celesticetin, chloramphenicol and thiostrepton as well as butanol and butylic alcohol. Spontaneous mutants resistant to these drugs have been isolated carrying single site mutations in their 23S rRNA gene; they include mutants of S. acidocaldarius resistant to chloramphenicol, carbomycin and celesticetin with the mutation C2452U and thiostrepton-resistant mutants of P. furiosus carrying the mutation A1067G (both numbers corresponding to Escherichia coli 23S rRNA). These mutated genes are being developed as selective markers. Moreover, two beta-galactosidase genes from P. furiosus have been cloned as possible phenotypic markers; one of these exhibits maximum activity at 95 degrees C with O-nitrophenyl beta-D-galactopyranoside as substrate.
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Affiliation(s)
- C Aagaard
- Institute of Molecular Biology, Copenhagen University, Denmark
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Robinson KA, Robb FT, Schreier HJ. Isolation of maltose-regulated genes from the hyperthermophilic archaeum, Pyrococcus furiosus, by subtractive hybridization. Gene 1994; 148:137-41. [PMID: 7523251 DOI: 10.1016/0378-1119(94)90247-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The hyperthermophilic archaeum, Pyrococcus furiosus, utilizes maltose as a preferred carbon source for growth. 32P-labeled complementary DNA (cDNA) probes representing maltose-regulated genes were obtained by a subtractive hybridization procedure that minimized retrieval of ribosomal RNA (rRNA) sequences during screening. Genomic DNA clones were isolated by positive hybridization to these probes. Genes whose expression varied both in the level of transcription, relative to rRNA, as well as in the degree of regulation were obtained; the extent of regulation varied over a wide range, from as little as fivefold to as high as 50-100-fold. DNA sequence analysis of several of these regulated genes indicated that the subtraction library included gene products required for maltose utilization (e.g., pyruvate dikinase), as well as growth-rate-related genes such as those encoding ribosomal proteins and RNA polymerase subunits. Our approach is applicable to studying gene regulation in organisms that are not amenable to classical genetic techniques.
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Affiliation(s)
- K A Robinson
- Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Baltimore 21202
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