1
|
Mijnendonckx K, Rogiers T, Giménez Del Rey FJ, Merroun ML, Williamson A, Ali MM, Charlier D, Leys N, Boon N, Van Houdt R. PrsQ 2, a small periplasmic protein involved in increased uranium resistance in the bacterium Cupriavidus metallidurans. JOURNAL OF HAZARDOUS MATERIALS 2023; 444:130410. [PMID: 36413896 DOI: 10.1016/j.jhazmat.2022.130410] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/10/2022] [Accepted: 11/14/2022] [Indexed: 06/16/2023]
Abstract
Uranium contamination is a widespread problem caused by natural and anthropogenic activities. Although microorganisms thrive in uranium-contaminated environments, little is known about the actual molecular mechanisms mediating uranium resistance. Here, we investigated the resistance mechanisms driving the adaptation of Cupriavidus metallidurans NA4 to toxic uranium concentrations. We selected a spontaneous mutant able to grow in the presence of 1 mM uranyl nitrate compared to 250 µM for the parental strain. The increased uranium resistance was acquired via the formation of periplasmic uranium-phosphate precipitates facilitated by the increased expression of a genus-specific small periplasmic protein, PrsQ2, regulated as non-cognate target of the CzcS2-CzcR2 two-component system. This study shows that bacteria can adapt to toxic uranium concentrations and explicates the complete genetic circuit behind the adaptation.
Collapse
Affiliation(s)
- Kristel Mijnendonckx
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
| | - Tom Rogiers
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
| | - Francisco J Giménez Del Rey
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium; Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Mohamed L Merroun
- Campus Fuentenueva, Department of Microbiology, University of Granada, Granada, Spain.
| | - Adam Williamson
- Center for Microbial Ecology and Technology, UGent, Ghent, Belgium.
| | - Md Muntasir Ali
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
| | - Daniel Charlier
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Natalie Leys
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
| | - Nico Boon
- Center for Microbial Ecology and Technology, UGent, Ghent, Belgium.
| | - Rob Van Houdt
- Microbiology Unit, Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK CEN, Mol, Belgium.
| |
Collapse
|
2
|
DNA-Binding Properties of a Novel Crenarchaeal Chromatin-Organizing Protein in Sulfolobus acidocaldarius. Biomolecules 2022; 12:biom12040524. [PMID: 35454113 PMCID: PMC9025068 DOI: 10.3390/biom12040524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/17/2022] [Accepted: 03/24/2022] [Indexed: 02/06/2023] Open
Abstract
In archaeal microorganisms, the compaction and organization of the chromosome into a dynamic but condensed structure is mediated by diverse chromatin-organizing proteins in a lineage-specific manner. While many archaea employ eukaryotic-type histones for nucleoid organization, this is not the case for the crenarchaeal model species Sulfolobus acidocaldarius and related species in Sulfolobales, in which the organization appears to be mostly reliant on the action of small basic DNA-binding proteins. There is still a lack of a full understanding of the involved proteins and their functioning. Here, a combination of in vitro and in vivo methodologies is used to study the DNA-binding properties of Sul12a, an uncharacterized small basic protein conserved in several Sulfolobales species displaying a winged helix–turn–helix structural motif and annotated as a transcription factor. Genome-wide chromatin immunoprecipitation and target-specific electrophoretic mobility shift assays demonstrate that Sul12a of S. acidocaldarius interacts with DNA in a non-sequence specific manner, while atomic force microscopy imaging of Sul12a–DNA complexes indicate that the protein induces structural effects on the DNA template. Based on these results, and a contrario to its initial annotation, it can be concluded that Sul12a is a novel chromatin-organizing protein.
Collapse
|
3
|
Sybers D, Joka Bernauw A, El Masri D, Ramadan Maklad H, Charlier D, De Mey M, Bervoets I, Peeters E. Engineering transcriptional regulation in Escherichia coli using an archaeal TetR-family transcription factor. Gene 2022; 809:146010. [PMID: 34688814 DOI: 10.1016/j.gene.2021.146010] [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: 05/31/2021] [Revised: 07/28/2021] [Accepted: 10/11/2021] [Indexed: 11/24/2022]
Abstract
Synthetic biology requires well-characterized biological parts that can be combined into functional modules. One type of biological parts are transcriptional regulators and their cognate operator elements, which enable to either generate an input-specific response or are used as actuator modules. A range of regulators has already been characterized and used for orthogonal gene expression engineering, however, previous efforts have mostly focused on bacterial regulators. This work aims to design and explore the use of an archaeal TetR family regulator, FadRSa from Sulfolobus acidocaldarius, in a bacterial system, namely Escherichia coli. This is a challenging objective given the fundamental difference between the bacterial and archaeal transcription machinery and the lack of a native TetR-like FadR regulatory system in E. coli. The synthetic σ70-dependent bacterial promoter proD was used as a starting point to design hybrid bacterial/archaeal promoter/operator regions, in combination with the mKate2 fluorescent reporter enabling a readout. Four variations of proD containing FadRSa binding sites were constructed and characterized. While expressional activity of the modified promoter proD was found to be severely diminished for two of the constructs, constructs in which the binding site was introduced adjacent to the -35 promoter element still displayed sufficient basal transcriptional activity and showed up to 7-fold repression upon expression of FadRSa. Addition of acyl-CoA has been shown to disrupt FadRSa binding to the DNA in vitro. However, extracellular concentrations of up to 2 mM dodecanoate, subsequently converted to acyl-CoA by the cell, did not have a significant effect on repression in the bacterial system. This work demonstrates that archaeal transcription regulators can be used to generate actuator elements for use in E. coli, although the lack of ligand response underscores the challenge of maintaining biological function when transferring parts to a phylogenetically divergent host.
Collapse
Affiliation(s)
- David Sybers
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Amber Joka Bernauw
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Diala El Masri
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Hassan Ramadan Maklad
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Daniel Charlier
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Marjan De Mey
- Centre for Synthetic Biology, Department of Biotechnology, Ghent University, Coupure Links 653, B-9000 Gent, Belgium
| | - Indra Bervoets
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | - Eveline Peeters
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
| |
Collapse
|
4
|
Lewis AM, Recalde A, Bräsen C, Counts JA, Nussbaum P, Bost J, Schocke L, Shen L, Willard DJ, Quax TEF, Peeters E, Siebers B, Albers SV, Kelly RM. The biology of thermoacidophilic archaea from the order Sulfolobales. FEMS Microbiol Rev 2021; 45:fuaa063. [PMID: 33476388 PMCID: PMC8557808 DOI: 10.1093/femsre/fuaa063] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 11/26/2020] [Indexed: 12/13/2022] Open
Abstract
Thermoacidophilic archaea belonging to the order Sulfolobales thrive in extreme biotopes, such as sulfuric hot springs and ore deposits. These microorganisms have been model systems for understanding life in extreme environments, as well as for probing the evolution of both molecular genetic processes and central metabolic pathways. Thermoacidophiles, such as the Sulfolobales, use typical microbial responses to persist in hot acid (e.g. motility, stress response, biofilm formation), albeit with some unusual twists. They also exhibit unique physiological features, including iron and sulfur chemolithoautotrophy, that differentiate them from much of the microbial world. Although first discovered >50 years ago, it was not until recently that genome sequence data and facile genetic tools have been developed for species in the Sulfolobales. These advances have not only opened up ways to further probe novel features of these microbes but also paved the way for their potential biotechnological applications. Discussed here are the nuances of the thermoacidophilic lifestyle of the Sulfolobales, including their evolutionary placement, cell biology, survival strategies, genetic tools, metabolic processes and physiological attributes together with how these characteristics make thermoacidophiles ideal platforms for specialized industrial processes.
Collapse
Affiliation(s)
- April M Lewis
- Department of Chemical and Biomolecular Engineering, North Carolina State University. Raleigh, NC 27695, USA
| | - Alejandra Recalde
- Institute for Biology, Molecular Biology of Archaea, University of Freiburg, 79104 Freiburg, Germany
| | - Christopher Bräsen
- Department of Molecular Enzyme Technology and Biochemistry, Environmental Microbiology and Biotechnology, and Centre for Water and Environmental Research, University of Duisburg-Essen, 45117 Essen, Germany
| | - James A Counts
- Department of Chemical and Biomolecular Engineering, North Carolina State University. Raleigh, NC 27695, USA
| | - Phillip Nussbaum
- Institute for Biology, Molecular Biology of Archaea, University of Freiburg, 79104 Freiburg, Germany
| | - Jan Bost
- Institute for Biology, Molecular Biology of Archaea, University of Freiburg, 79104 Freiburg, Germany
| | - Larissa Schocke
- Department of Molecular Enzyme Technology and Biochemistry, Environmental Microbiology and Biotechnology, and Centre for Water and Environmental Research, University of Duisburg-Essen, 45117 Essen, Germany
| | - Lu Shen
- Department of Molecular Enzyme Technology and Biochemistry, Environmental Microbiology and Biotechnology, and Centre for Water and Environmental Research, University of Duisburg-Essen, 45117 Essen, Germany
| | - Daniel J Willard
- Department of Chemical and Biomolecular Engineering, North Carolina State University. Raleigh, NC 27695, USA
| | - Tessa E F Quax
- Archaeal Virus–Host Interactions, Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Eveline Peeters
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, 1050 Brussels, Belgium
| | - Bettina Siebers
- Department of Molecular Enzyme Technology and Biochemistry, Environmental Microbiology and Biotechnology, and Centre for Water and Environmental Research, University of Duisburg-Essen, 45117 Essen, Germany
| | - Sonja-Verena Albers
- Institute for Biology, Molecular Biology of Archaea, University of Freiburg, 79104 Freiburg, Germany
| | - Robert M Kelly
- Department of Chemical and Biomolecular Engineering, North Carolina State University. Raleigh, NC 27695, USA
| |
Collapse
|
5
|
Lemmens L, Tilleman L, De Koning E, Valegård K, Lindås AC, Van Nieuwerburgh F, Maes D, Peeters E. YtrA Sa, a GntR-Family Transcription Factor, Represses Two Genetic Loci Encoding Membrane Proteins in Sulfolobus acidocaldarius. Front Microbiol 2019; 10:2084. [PMID: 31552000 PMCID: PMC6746942 DOI: 10.3389/fmicb.2019.02084] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 08/23/2019] [Indexed: 11/25/2022] Open
Abstract
In bacteria, the GntR family is a widespread family of transcription factors responsible for the regulation of a myriad of biological processes. In contrast, despite their occurrence in archaea only a little information is available on the function of GntR-like transcription factors in this domain of life. The thermoacidophilic crenarchaeon Sulfolobus acidocaldarius harbors a GntR-like regulator belonging to the YtrA subfamily, encoded as the first gene in an operon with a second gene encoding a putative membrane protein. Here, we present a detailed characterization of this regulator, named YtrASa, with a focus on regulon determination and mechanistic analysis with regards to DNA binding. Genome-wide chromatin immunoprecipitation and transcriptome experiments, the latter employing a ytrASa overexpression strain, demonstrate that the regulator acts as a repressor on a very restricted regulon, consisting of only two targets including the operon encoding its own gene and a distinct genetic locus encoding another putative membrane protein. For both targets, a conserved 14-bp semi-palindromic binding motif was delineated that covers the transcriptional start site and that is surrounded by additional half-site motifs. The crystallographic structure of YtrASa was determined, revealing a compact dimeric structure in which the DNA-binding motifs are oriented ideally to enable a specific high-affinity interaction with the core binding motif. This study provides new insights into the functioning of a YtrA-like regulator in the archaeal domain of life.
Collapse
Affiliation(s)
- Liesbeth Lemmens
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Laurentijn Tilleman
- Laboratory for Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Ezra De Koning
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Karin Valegård
- Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
| | - Ann-Christin Lindås
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Filip Van Nieuwerburgh
- Laboratory for Pharmaceutical Biotechnology, Faculty of Pharmaceutical Sciences, Ghent University, Ghent, Belgium
| | - Dominique Maes
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Eveline Peeters
- Research Group of Microbiology, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| |
Collapse
|
6
|
Li L, Banerjee A, Bischof LF, Maklad HR, Hoffmann L, Henche AL, Veliz F, Bildl W, Schulte U, Orell A, Essen LO, Peeters E, Albers SV. Wing phosphorylation is a major functional determinant of the Lrs14-type biofilm and motility regulator AbfR1 in Sulfolobus acidocaldarius. Mol Microbiol 2017. [PMID: 28628237 DOI: 10.1111/mmi.13735] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
In response to a variety of environmental cues, prokaryotes can switch between a motile and a sessile, biofilm-forming mode of growth. The regulatory mechanisms and signaling pathways underlying this switch are largely unknown in archaea but involve small winged helix-turn-helix DNA-binding proteins of the archaea-specific Lrs14 family. Here, we study the Lrs14 member AbfR1 of Sulfolobus acidocaldarius. Small-angle X-ray scattering data are presented, which are consistent with a model of dimeric AbfR1 in which dimerization occurs via an antiparallel coiled coil as suggested by homology modeling. Furthermore, solution structure data of AbfR1-DNA complexes suggest that upon binding DNA, AbfR1 induces deformations in the DNA. The wing residues tyrosine 84 and serine 87, which are phosphorylated in vivo, are crucial to establish stable protein-DNA contacts and their substitution with a negatively charged glutamate or aspartate residue inhibits formation of a nucleoprotein complex. Furthermore, mutation abrogates the cellular abundance and transcription regulatory function of AbfR1 and thus affects the resulting biofilm and motility phenotype of S. acidocaldarius. This work establishes a novel wHTH DNA-binding mode for Lrs14-like proteins and hints at an important role for protein phosphorylation as a signal transduction mechanism for the control of biofilm formation and motility in archaea.
Collapse
Affiliation(s)
- Lingling Li
- Molecular Biology of Archaea, Institute of Biology II, University of Freiburg, Freiburg, Germany
| | - Ankan Banerjee
- Structural Biochemistry, Department of Chemistry, Philipps University of Marburg, Marburg, Germany
| | - Lisa Franziska Bischof
- Molecular Biology of Archaea, Institute of Biology II, University of Freiburg, Freiburg, Germany.,Spemann Graduate School of Biology and Medicine, Freiburg, Germany
| | - Hassan Ramadan Maklad
- Research Group of Microbiology, Department of Bio-engineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Lena Hoffmann
- Molecular Biology of Archaea, Institute of Biology II, University of Freiburg, Freiburg, Germany
| | - Anna-Lena Henche
- Molecular Biology of Archaea, Institute of Biology II, University of Freiburg, Freiburg, Germany
| | - Fabian Veliz
- Molecular Microbiology of Extremophiles Group, Centre for Genomics and Bioinformatics, Faculty of Sciences, University Mayor, Santiago, Chile
| | - Wolfgang Bildl
- Institute of Physiology, University of Freiburg, Freiburg, Germany
| | - Uwe Schulte
- Institute of Physiology, University of Freiburg, Freiburg, Germany.,Center for Biological Signaling Studies (BIOSS), Freiburg, Germany
| | - Alvaro Orell
- Molecular Biology of Archaea, Institute of Biology II, University of Freiburg, Freiburg, Germany.,Molecular Microbiology of Extremophiles Group, Centre for Genomics and Bioinformatics, Faculty of Sciences, University Mayor, Santiago, Chile.,Max Planck Institute of Terrestrial Microbiology, Marburg, Germany
| | - Lars-Oliver Essen
- Structural Biochemistry, Department of Chemistry, Philipps University of Marburg, Marburg, Germany.,LOEWE Center for Synthetic Microbiology, Marburg, Germany
| | - Eveline Peeters
- Research Group of Microbiology, Department of Bio-engineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Sonja-Verena Albers
- Molecular Biology of Archaea, Institute of Biology II, University of Freiburg, Freiburg, Germany
| |
Collapse
|
7
|
Transcription Factor-Mediated Gene Regulation in Archaea. RNA METABOLISM AND GENE EXPRESSION IN ARCHAEA 2017. [DOI: 10.1007/978-3-319-65795-0_2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
|
8
|
Novel stand-alone RAM domain protein-mediated catalytic control of anthranilate phosphoribosyltransferase in tryptophan biosynthesis in Thermus thermophilus. Extremophiles 2016; 21:73-83. [DOI: 10.1007/s00792-016-0884-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 10/10/2016] [Indexed: 10/20/2022]
|
9
|
Pseudomonas aeruginosa LysR PA4203 regulator NmoR acts as a repressor of the PA4202 nmoA gene, encoding a nitronate monooxygenase. J Bacteriol 2014; 197:1026-39. [PMID: 25384477 DOI: 10.1128/jb.01991-14] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The PA4203 gene encodes a LysR regulator and lies between the ppgL gene (PA4204), which encodes a periplasmic gluconolactonase, and, in the opposite orientation, the PA4202 (nmoA) gene, coding for a nitronate monooxygenase, and ddlA (PA4201), encoding a d-alanine alanine ligase. The intergenic regions between PA4203 and ppgL and between PA4203 and nmoA are very short (79 and 107 nucleotides, respectively). Here we show that PA4203 (nmoR) represses its own transcription and the expression of nmoA. A chromatin immunoprecipitation analysis showed the presence of a single NmoR binding site between nmoA and nmoR, which was confirmed by electrophoretic mobility shift assays (EMSAs) with the purified NmoR protein. Despite this observation, a transcriptome analysis revealed more genes to be affected in an nmoR mutant, including genes known to be part of the MexT LysR activator regulon. The PA1225 gene, encoding a quinone oxidoreductase, was the most highly upregulated gene in the nmoR deletion mutant, independently of MexT. Finally, deletion of the nmoA gene resulted in an increased sensitivity of the cells to 3-nitropropionic acid (3-NPA), confirming the role of the nitronate monooxygenase protein in the detoxification of nitronate.
Collapse
|
10
|
AxyR, an AraC Family Transcriptional Activator of the Xylanase 3 Gene, Requires Xylo-Oligosaccharides as a Cofactor for DNA Binding inPaenibacillussp. Strain W-61. Biosci Biotechnol Biochem 2014; 76:1051-4. [DOI: 10.1271/bbb.120165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
11
|
Liu H, Orell A, Maes D, van Wolferen M, Lindås AC, Bernander R, Albers SV, Charlier D, Peeters E. BarR, an Lrp-type transcription factor in Sulfolobus acidocaldarius, regulates an aminotransferase gene in a β-alanine responsive manner. Mol Microbiol 2014; 92:625-39. [PMID: 24646198 DOI: 10.1111/mmi.12583] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/15/2014] [Indexed: 12/29/2022]
Abstract
In archaea, nothing is known about the β-alanine degradation pathway or its regulation. In this work, we identify and characterize BarR, a novel Lrp-like transcription factor and the first one that has a non-proteinogenic amino acid ligand. BarR is conserved in Sulfolobus acidocaldarius and Sulfolobus tokodaii and is located in a divergent operon with a gene predicted to encode β-alanine aminotransferase. Deletion of barR resulted in a reduced exponential growth rate in the presence of β-alanine. Furthermore, qRT-PCR and promoter activity assays demonstrated that BarR activates the expression of the adjacent aminotransferase gene, but only upon β-alanine supplementation. In contrast, auto-activation proved to be β-alanine independent. Heterologously produced BarR is an octamer in solution and forms a single complex by interacting with multiple sites in the 170 bp long intergenic region separating the divergently transcribed genes. In vitro, DNA binding is specifically responsive to β-alanine and site-mutant analyses indicated that β-alanine directly interacts with the ligand-binding pocket. Altogether, this work contributes to the growing body of evidence that in archaea, Lrp-like transcription factors have physiological roles that go beyond the regulation of α-amino acid metabolism.
Collapse
Affiliation(s)
- Han Liu
- Research Group of Microbiology, Department of Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050, Brussels, Belgium
| | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Abstract
The ability of organisms to sense and respond to their environment is essential to their survival. This is no different for members of the third domain of life, the Archaea. Archaea are found in diverse and often extreme habitats. However, their ability to sense and respond to their environment at the level of gene expression has been understudied when compared to bacteria and eukaryotes. Over the last decade, the field has expanded, and a variety of unique and interesting regulatory schemes have been unraveled. In this review, the current state of knowledge of archaeal transcription regulation is explored.
Collapse
|
13
|
Nguyen-Duc T, van Oeffelen L, Song N, Hassanzadeh-Ghassabeh G, Muyldermans S, Charlier D, Peeters E. The genome-wide binding profile of the Sulfolobus solfataricus transcription factor Ss-LrpB shows binding events beyond direct transcription regulation. BMC Genomics 2013; 14:828. [PMID: 24274039 PMCID: PMC4046817 DOI: 10.1186/1471-2164-14-828] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 11/15/2013] [Indexed: 11/18/2022] Open
Abstract
Background Gene regulatory processes are largely resulting from binding of transcription factors to specific genomic targets. Leucine-responsive Regulatory Protein (Lrp) is a prevalent transcription factor family in prokaryotes, however, little information is available on biological functions of these proteins in archaea. Here, we study genome-wide binding of the Lrp-like transcription factor Ss-LrpB from Sulfolobus solfataricus. Results Chromatin immunoprecipitation in combination with DNA microarray analysis (ChIP-chip) has revealed that Ss-LrpB interacts with 36 additional loci besides the four previously identified local targets. Only a subset of the newly identified binding targets, concentrated in a highly variable IS-dense genomic region, is also bound in vitro by pure Ss-LrpB. There is no clear relationship between the in vitro measured DNA-binding specificity of Ss-LrpB and the in vivo association suggesting a limited permissivity of the crenarchaeal chromatin for transcription factor binding. Of 37 identified binding regions, 29 are co-bound by LysM, another Lrp-like transcription factor in S. solfataricus. Comparative gene expression analysis in an Ss-lrpB mutant strain shows no significant Ss-LrpB-mediated regulation for most targeted genes, with exception of the CRISPR B cluster, which is activated by Ss-LrpB through binding to a specific motif in the leader region. Conclusions The genome-wide binding profile presented here implies that Ss-LrpB is associated at additional genomic binding sites besides the local gene targets, but acts as a specific transcription regulator in the tested growth conditions. Moreover, we have provided evidence that two Lrp-like transcription factors in S. solfataricus, Ss-LrpB and LysM, interact in vivo. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-14-828) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
| | | | | | | | | | | | - Eveline Peeters
- Research group of Microbiology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
| |
Collapse
|
14
|
Contursi P, Fusco S, Limauro D, Fiorentino G. Host and viral transcriptional regulators in Sulfolobus: an overview. Extremophiles 2013; 17:881-95. [PMID: 24085522 DOI: 10.1007/s00792-013-0586-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 09/16/2013] [Indexed: 12/29/2022]
Abstract
The genus Sulfolobus includes microorganisms belonging to the domain Archaea, sub-kingdom Crenarchaeota, living in geographically distant acidic hot springs. Their adaptation to such particular habitats requires finely regulated mechanisms of gene expression, among which, those modulated by sequence-specific transcription factors (TFs) play a key role. In this review, we summarize the current knowledge on the repertoires of TFs found in Sulfolobus spp. and their viruses, focusing on the description of their DNA-binding domains and their structure-function relationship.
Collapse
Affiliation(s)
- Patrizia Contursi
- Dipartimento di Biologia, Università di Napoli Federico II, via Cinthia, Edificio 7, 80126, Napoli, Italy
| | | | | | | |
Collapse
|
15
|
Peeters E, van Oeffelen L, Nadal M, Forterre P, Charlier D. A thermodynamic model of the cooperative interaction between the archaeal transcription factor Ss-LrpB and its tripartite operator DNA. Gene 2013; 524:330-40. [PMID: 23603352 DOI: 10.1016/j.gene.2013.03.118] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 03/07/2013] [Indexed: 10/26/2022]
Abstract
Ss-LrpB is a transcription factor of the archaeon Sulfolobus solfataricus that belongs to the leucine-responsive regulatory protein family. This protein binds to three distinct binding sites in the control region of its own gene, suggestive of autoregulation. Here, we present a detailed study of the thermodynamic and conformational rules that govern the interaction between Ss-LrpB and its tripartite operator DNA. Lane-per-lane partition analysis of macroscopic binding state populations in electrophoretic mobility shift assays, probing binding to full-length, truncated and mutated forms of the operator, allowed determination of equilibrium association constants and cooperativity parameters. The resulting thermodynamic model demonstrates that the Ss-LrpB-operator regulatory complex is formed with a significant positive cooperativity, which is mostly arising from dimer-dimer interactions between pairs of adjacent binding sites. There is a constraint on the spacing between these binding sites, with a preference for a cis-alignment on the DNA helix and with a 16-bp linker yielding maximal pairwise cooperativity. DNase I footprinting assays demonstrated that the extent of Ss-LrpB-induced DNA deformations depends on linker length. The knowledge of the thermodynamic principles underlying the Ss-LrpB-operator interaction, presented here, will contribute to unraveling of the cis-regulatory code of Ss-LrpB autoregulation.
Collapse
Affiliation(s)
- Eveline Peeters
- Research group of Microbiology, Department of Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium.
| | | | | | | | | |
Collapse
|
16
|
Song N, Nguyen Duc T, van Oeffelen L, Muyldermans S, Peeters E, Charlier D. Expanded target and cofactor repertoire for the transcriptional activator LysM from Sulfolobus. Nucleic Acids Res 2013; 41:2932-49. [PMID: 23355617 PMCID: PMC3597687 DOI: 10.1093/nar/gkt021] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Previously, Lrp-like transcriptional regulator LysM from the hyperthermoacidophilic crenarchaeon Sulfolobus solfataricus was proposed to have a single target, the lysWXJK operon of lysine biosynthesis, and a single effector molecule, l-lysine. Here we identify ∼70 novel binding sites for LysM in the S. solfataricus genome with a LysM-specific nanobody-based chromatin immunoprecipitation assay coupled to microarray hybridization (ChIP-chip) and in silico target site prediction using an energy-based position weight matrix, and validate these findings with in vitro binding. LysM binds to intergenic and coding regions, including promoters of various amino acid biosynthesis and transport genes. We confirm that l-lysine is the most potent effector molecule that reduces, but does not completely abolish, LysM binding, and show that several other amino acids and derivatives, including d-lysine, l-arginine, l-homoarginine, l-glutamine and l-methionine and branched-chain amino acids l-leucine, l-isoleucine and l-valine, significantly affect DNA-binding properties of LysM. Therefore, it appears from this study that LysM is a much more versatile regulator than previously thought, and that it uses a variety of amino acids to sense nutritional quality of the environment and to modulate expression of the metabolic machinery of Sulfolobus accordingly.
Collapse
Affiliation(s)
- Ningning Song
- Research Group of Microbiology, Department of Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | | | | | | | | | | |
Collapse
|
17
|
Nguyen-Duc T, Peeters E, Muyldermans S, Charlier D, Hassanzadeh-Ghassabeh G. Nanobody(R)-based chromatin immunoprecipitation/micro-array analysis for genome-wide identification of transcription factor DNA binding sites. Nucleic Acids Res 2012; 41:e59. [PMID: 23275538 PMCID: PMC3597646 DOI: 10.1093/nar/gks1342] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Nanobodies® are single-domain antibody fragments derived from camelid heavy-chain antibodies. Because of their small size, straightforward production in Escherichia coli, easy tailoring, high affinity, specificity, stability and solubility, nanobodies® have been exploited in various biotechnological applications. A major challenge in the post-genomics and post-proteomics era is the identification of regulatory networks involving nucleic acid-protein and protein-protein interactions. Here, we apply a nanobody® in chromatin immunoprecipitation followed by DNA microarray hybridization (ChIP-chip) for genome-wide identification of DNA-protein interactions. The Lrp-like regulator Ss-LrpB, arguably one of the best-studied specific transcription factors of the hyperthermophilic archaeon Sulfolobus solfataricus, was chosen for this proof-of-principle nanobody®-assisted ChIP. Three distinct Ss-LrpB-specific nanobodies®, each interacting with a different epitope, were generated for ChIP. Genome-wide ChIP-chip with one of these nanobodies® identified the well-established Ss-LrpB binding sites and revealed several unknown target sequences. Furthermore, these ChIP-chip profiles revealed auxiliary operator sites in the open reading frame of Ss-lrpB. Our work introduces nanobodies® as a novel class of affinity reagents for ChIP. Taking into account the unique characteristics of nanobodies®, in particular, their short generation time, nanobody®-based ChIP is expected to further streamline ChIP-chip and ChIP-Seq experiments, especially in organisms with no (or limited) possibility of genetic manipulation.
Collapse
Affiliation(s)
- Trong Nguyen-Duc
- Research group of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | | | | | | | | |
Collapse
|
18
|
Vassart A, Van Wolferen M, Orell A, Hong Y, Peeters E, Albers SV, Charlier D. Sa-Lrp from Sulfolobus acidocaldarius is a versatile, glutamine-responsive, and architectural transcriptional regulator. Microbiologyopen 2012; 2:75-93. [PMID: 23255531 PMCID: PMC3584215 DOI: 10.1002/mbo3.58] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 11/12/2012] [Accepted: 11/13/2012] [Indexed: 11/30/2022] Open
Abstract
Sa-Lrp is a member of the leucine-responsive regulatory protein (Lrp)-like family of transcriptional regulators in Sulfolobus acidocaldarius. Previously, we demonstrated the binding of Sa-Lrp to the control region of its own gene in vitro. However, the function and cofactor of Sa-Lrp remained an enigma. In this work, we demonstrate that glutamine is the cofactor of Sa-Lrp by inducing the formation of octamers and increasing the DNA-binding affinity and sequence specificity. In vitro protein-DNA interaction assays indicate that Sa-Lrp binds to promoter regions of genes with a variety of functions including ammonia assimilation, transcriptional control, and UV-induced pili synthesis. DNA binding occurs with a specific affinity for AT-rich binding sites, and the protein induces DNA bending and wrapping upon binding, indicating an architectural role of the regulator. Furthermore, by analyzing an Sa-lrp deletion mutant, we demonstrate that the protein affects transcription of some of the genes of which the promoter region is targeted and that it is an important determinant of the cellular aggregation phenotype. Taking all these results into account, we conclude that Sa-Lrp is a glutamine-responsive global transcriptional regulator with an additional architectural role.
Collapse
Affiliation(s)
- Amelia Vassart
- Research Group of Microbiology, Faculty of Sciences and Bio-engineering Sciences, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium
| | | | | | | | | | | | | |
Collapse
|
19
|
Agustiandari H, Peeters E, de Wit JG, Charlier D, Driessen AJM. LmrR-mediated gene regulation of multidrug resistance in Lactococcus lactis. MICROBIOLOGY-SGM 2011; 157:1519-1530. [PMID: 21330438 DOI: 10.1099/mic.0.048025-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Multidrug resistance (MDR) in Lactococcus lactis is due to the expression of the membrane ATP-binding cassette (ABC) transporter LmrCD. In the absence of drugs, the transcriptional regulator LmrR prevents expression of the lmrCD operon by binding to its operator site. Through an autoregulatory mechanism LmrR also suppresses its own expression. Although the lmrR and lmrCD genes have their own promoters, primer extension analysis showed the presence of a long transcript spanning the entire lmrR-lmrCD cluster, in addition to various shorter transcripts harbouring the lmrCD genes only. 'In-gel' Cu-phenanthroline footprinting analysis indicated an extensive interaction between LmrR and the lmrR promoter/operator region. Atomic force microscopy imaging of the binding of LmrR to the control region of lmrR DNA showed severe deformations indicative of DNA wrapping and looping, while LmrR binding to a fragment containing the lmrCD control region induced DNA bending. The results further suggest a drug-dependent regulation mechanism in which the lmrCD genes are co-transcribed with lmrR as a polycistronic messenger. This leads to an LmrR-mediated regulation of lmrCD expression that is exerted from two different locations and by distinct regulatory mechanisms.
Collapse
Affiliation(s)
- Herfita Agustiandari
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and The Kluyver Centre for the Genomics of Industrial Fermentation, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Eveline Peeters
- Erfelijkheidsleer en Microbiologie, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| | - Janny G de Wit
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and The Kluyver Centre for the Genomics of Industrial Fermentation, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| | - Daniel Charlier
- Erfelijkheidsleer en Microbiologie, Vrije Universiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
| | - Arnold J M Driessen
- Department of Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute and The Kluyver Centre for the Genomics of Industrial Fermentation, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
| |
Collapse
|
20
|
The Lrp family of transcription regulators in archaea. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2010; 2010:750457. [PMID: 21151646 PMCID: PMC2995911 DOI: 10.1155/2010/750457] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Accepted: 10/20/2010] [Indexed: 11/26/2022]
Abstract
Archaea possess a eukaryotic-type basal transcription apparatus that is regulated by bacteria-like transcription regulators. A universal and abundant family of transcription regulators are the bacterial/archaeal Lrp-like regulators. The Lrp family is one of the best studied regulator families in archaea, illustrated by investigations of proteins from the archaeal model organisms: Sulfolobus, Pyrococcus, Methanocaldococcus, and Halobacterium. These regulators are extremely versatile in their DNA-binding properties, response to effector molecules, and molecular regulatory mechanisms. Besides being involved in the regulation of the amino acid metabolism, they also regulate central metabolic processes. It appears that these regulatory proteins are also involved in large regulatory networks, because of hierarchical regulations and the possible combinatorial use of different Lrp-like proteins. Here, we discuss the recent developments in our understanding of this important class of regulators.
Collapse
|
21
|
Schwaiger R, Schwarz C, Furtwängler K, Tarasov V, Wende A, Oesterhelt D. Transcriptional control by two leucine-responsive regulatory proteins in Halobacterium salinarum R1. BMC Mol Biol 2010; 11:40. [PMID: 20509863 PMCID: PMC2894021 DOI: 10.1186/1471-2199-11-40] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Accepted: 05/28/2010] [Indexed: 12/26/2022] Open
Abstract
Background Archaea combine bacterial-as well as eukaryotic-like features to regulate cellular processes. Halobacterium salinarum R1 encodes eight leucine-responsive regulatory protein (Lrp)-homologues. The function of two of them, Irp (OE3923F) and lrpA1 (OE2621R), were analyzed by gene deletion and overexpression, including genome scale impacts using microarrays. Results It was shown that Lrp affects the transcription of multiple target genes, including those encoding enzymes involved in amino acid synthesis, central metabolism, transport processes and other regulators of transcription. In contrast, LrpA1 regulates transcription in a more specific manner. The aspB3 gene, coding for an aspartate transaminase, was repressed by LrpA1 in the presence of L-aspartate. Analytical DNA-affinity chromatography was adapted to high salt, and demonstrated binding of LrpA1 to its own promoter, as well as L-aspartate dependent binding to the aspB3 promoter. Conclusion The gene expression profiles of two archaeal Lrp-homologues report in detail their role in H. salinarum R1. LrpA1 and Lrp show similar functions to those already described in bacteria, but in addition they play a key role in regulatory networks, such as controlling the transcription of other regulators. In a more detailed analysis ligand dependent binding of LrpA1 was demonstrated to its target gene aspB3.
Collapse
Affiliation(s)
- Rita Schwaiger
- Max Planck Institute of Biochemistry, Department of Membrane Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | | | | | | | | | | |
Collapse
|
22
|
Peeters E, Albers SV, Vassart A, Driessen AJM, Charlier D. Ss-LrpB, a transcriptional regulator fromSulfolobus solfataricus, regulates a gene cluster with a pyruvate ferredoxin oxidoreductase-encoding operon and permease genes. Mol Microbiol 2009; 71:972-88. [DOI: 10.1111/j.1365-2958.2008.06578.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
23
|
Reddy MCM, Gokulan K, Jacobs WR, Ioerger TR, Sacchettini JC. Crystal structure of Mycobacterium tuberculosis LrpA, a leucine-responsive global regulator associated with starvation response. Protein Sci 2008; 17:159-70. [PMID: 18042675 PMCID: PMC2144582 DOI: 10.1110/ps.073192208] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 09/22/2007] [Accepted: 09/27/2007] [Indexed: 10/22/2022]
Abstract
The bacterial leucine-responsive regulatory protein (Lrp) is a global transcriptional regulator that controls the expression of many genes during starvation and the transition to stationary phase. The Mycobacterium tuberculosis gene Rv3291c encodes a 150-amino acid protein (designated here as Mtb LrpA) with homology with Escherichia coli Lrp. The crystal structure of the native form of Mtb LrpA was solved at 2.1 A. The Mtb LrpA structure shows an N-terminal DNA-binding domain with a helix-turn-helix (HTH) motif, and a C-terminal regulatory domain. In comparison to the complex of E. coli AsnC with asparagine, the effector-binding pocket (including loop 100-106) in LrpA appears to be largely preserved, with hydrophobic substitutions consistent with its specificity for leucine. The effector-binding pocket is formed at the interface between adjacent dimers, with an opening to the core of the octamer as in AsnC, and an additional substrate-access channel opening to the outer surface of the octamer. Using electrophoretic mobility shift assays, purified Mtb LrpA protein was shown to form a protein-DNA complex with the lat promoter, demonstrating that the lat operon is a direct target of LrpA. Using computational analysis, a putative motif is identified in this region that is also present upstream of other operons differentially regulated under starvation. This study provides insights into the potential role of LrpA as a global regulator in the transition of M. tuberculosis to a persistent state.
Collapse
Affiliation(s)
- Manchi C M Reddy
- Department of Biochemistry and Biophysics, Texas A and M University, College Station, Texas 77843-2128, USA
| | | | | | | | | |
Collapse
|
24
|
First characterisation of the active oligomer form of sulfur oxygenase reductase from the bacterium Aquifex aeolicus. Extremophiles 2007; 12:205-15. [PMID: 18060346 DOI: 10.1007/s00792-007-0119-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Accepted: 10/08/2007] [Indexed: 10/22/2022]
Abstract
Sulfur oxygenase reductase (SOR) enzyme is responsible for the initial oxidation step of elemental sulfur in archaea. Curiously, Aquifex aeolicus, a hyperthermophilic, chemolithoautotrophic and microaerophilic bacterium, has the SOR-encoding gene in its genome. We showed, for the first time the presence of the SOR enzyme in A. aeolicus, its gene was cloned and recombinantly expressed in Escherichia coli and the protein was purified and characterised. It is a 16 homo-oligomer of approximately 600 kDa that contains iron atoms indispensable for the enzyme activity. The optimal temperature of SOR activity is 80 degrees C and it is inactive at 20 degrees C. Studies of the factors involved in getting the fully active molecule at high temperature show clearly that (1) incubation at high temperature induces more homogeneous form of the enzyme, (2) conformational changes observed at high temperature are required to get the fully active molecule and (3) acquisition of an active conformation induced by the temperature seems to be more important than the subunit number. Differences between A. aeolicus SOR and the archaea SORs are described.
Collapse
|
25
|
Shinkai A, Sekine SI, Urushibata A, Terada T, Shirouzu M, Yokoyama S. The putative DNA-binding protein Sto12a from the thermoacidophilic archaeon Sulfolobus tokodaii contains intrachain and interchain disulfide bonds. J Mol Biol 2007; 372:1293-304. [PMID: 17720190 DOI: 10.1016/j.jmb.2007.07.051] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2007] [Revised: 07/20/2007] [Accepted: 07/23/2007] [Indexed: 11/24/2022]
Abstract
The Sto12a protein, from the thermoacidophilic archaeon Sulfolobus tokodaii, has been identified as a small putative DNA-binding protein. Most of the proteins with a high level of amino acid sequence homology to this protein are derived from members of the Sulfolobaceae family, including a transcriptional regulator. We determined the crystal structure of Sto12a at 2.05 A resolution by multiple-wavelength anomalous dispersion phasing from the selenomethionine-containing protein crystal. This is the first structure of a member of this family of DNA-binding proteins. The Sto12a protein forms a homodimer, and the structure is composed of an N-terminal alpha-helix, a winged-helix-turn-helix domain, and a C-terminal alpha-helix that forms an interchain antiparallel coiled coil. The two winged-helix domains are located at both ends of the coiled coil, with putative DNA-recognition helices separated by approximately 34 A. A structural homology search indicated that the winged-helix domain shared a high level of homology with those found in B-DNA- or Z-DNA-binding proteins from various species, including archaea, bacteria, and human, despite a low level of sequence similarity. The unique structural features of the Sto12a protein include intrachain and interchain disulfide bonds, which stabilize the chain and homodimer structures. There are three cysteine residues: Cys15 and Cys16 in the N-terminal alpha-helix, and Cys100 in the C-terminal alpha-helix. Cys15 is involved in an interchain disulfide bridge with the other Cys15, and Cys16 forms an intrachain disulfide bridge with Cys100. This is a novel fold among winged-helix DNA-binding proteins. Possible DNA-binding interactions of the Sto12a protein are discussed based on the crystal structure of Sto12a and comparisons to other winged-helix DNA-binding proteins.
Collapse
Affiliation(s)
- Akeo Shinkai
- RIKEN SPring-8 Center, Harima Institute, 1-1-1 Kouto, Sayo, Hyogo 679-5148, Japan
| | | | | | | | | | | |
Collapse
|
26
|
Peeters E, Wartel C, Maes D, Charlier D. Analysis of the DNA-binding sequence specificity of the archaeal transcriptional regulator Ss-LrpB from Sulfolobus solfataricus by systematic mutagenesis and high resolution contact probing. Nucleic Acids Res 2006; 35:623-33. [PMID: 17178749 PMCID: PMC1802622 DOI: 10.1093/nar/gkl1095] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
To determine the sequence specificity of dimeric Ss-LrpB, a high resolution contact map was constructed and a saturation mutagenesis conducted on one half of the palindromic consensus box. Premodification binding interference indicates that Ss-LrpB establishes most of its tightest contacts with a single strand of two major groove segments and interacts with the minor groove at the center of the box. The requirement for bending is reflected in the preference for an A+T rich center and confirmed with C·G and C·I substitutions. The saturation mutagenesis indicates that major groove contacts with C·G at position 5 and its symmetrical counterpart are most critical for the specificity and strength of the interaction. Conservation at the remaining positions improved the binding. Hydrogen bonding to the O6 and N7 acceptor atoms of the G5′ residue play a major role in complex formation. Unlike many other DNA-binding proteins Ss-LrpB does not establish hydrophobic interactions with the methyls of thymine residues. The binding energies determined from the saturation mutagenesis were used to construct a sequence logo, which pin-points the overwhelming importance of C·G at position 5. The knowledge of the DNA-binding specificity will constitute a precious tool for the search of new physiologically relevant binding sites for Ss-LrpB in the genome.
Collapse
Affiliation(s)
| | | | - Dominique Maes
- Laboratorium voor Ultrastructuur, Vrije Universiteit Brussel and Vlaams interuniversitair Instituut voor Biotechnologie (VIB)Pleinlaan 2, B-1050 Brussel, Belgium
| | - Daniel Charlier
- To whom correspondence should be addressed. Tel: +32 2 629 13 42; Fax: +32 2 629 13 45;
| |
Collapse
|
27
|
Lubelska JM, Jonuscheit M, Schleper C, Albers SV, Driessen AJM. Regulation of expression of the arabinose and glucose transporter genes in the thermophilic archaeon Sulfolobus solfataricus. Extremophiles 2006; 10:383-91. [PMID: 16604273 DOI: 10.1007/s00792-006-0510-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Accepted: 01/04/2006] [Indexed: 10/24/2022]
Abstract
Sugar uptake in Sulfolobus solfataricus, a thermoacidophilic archaeon, occurs through high-affinity binding of protein-dependent ABC transporters. We have investigated the expression patterns of two sugar transport operons, that is, the glucose and arabinose transporters. Analysis of the araS promoter activity, and the mRNA and protein levels in S. solfataricus cells grown on different carbon sources showed that expression of the arabinose transporter gene cluster is highly regulated and dependent on the presence of arabinose in the medium. Glucose in the growth medium repressed the expression of the arabinose transport genes. By means of primer extension, the transcriptional start site for the arabinose operon was mapped. Interestingly, expression of the arabinose transporter is down-regulated by addition of a selective set of amino acids to the medium. Expression of the glucose transporter genes appeared constitutive. These data confirm the earlier observation of a catabolite repression-like system in S. solfataricus.
Collapse
Affiliation(s)
- Joanna M Lubelska
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9751 NN Haren, The Netherlands
| | | | | | | | | |
Collapse
|
28
|
Yokoyama K, Ishijima SA, Clowney L, Koike H, Aramaki H, Tanaka C, Makino K, Suzuki M. Feast/famine regulatory proteins (FFRPs): Escherichia coli Lrp, AsnC and related archaeal transcription factors. FEMS Microbiol Rev 2006; 30:89-108. [PMID: 16438681 DOI: 10.1111/j.1574-6976.2005.00005.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Feast/famine regulatory proteins comprise a diverse family of transcription factors, which have been referred to in various individual identifications, including Escherichia coli leucine-responsive regulatory protein and asparagine synthase C gene product. A full length feast/famine regulatory protein consists of the N-terminal DNA-binding domain and the C-domain, which is involved in dimerization and further assembly, thereby producing, for example, a disc or a chromatin-like cylinder. Various ligands of the size of amino acids bind at the interface between feast/famine regulatory protein dimers, thereby altering their assembly forms. Also, the combination of feast/famine regulatory protein subunits forming the same assembly is altered. In this way, a small number of feast/famine regulatory proteins are able to regulate a large number of genes in response to various environmental changes. Because feast/famine regulatory proteins are shared by archaea and eubacteria, the genome-wide regulation by feast/famine regulatory proteins is traceable back to their common ancestor, being the prototype of highly differentiated transcription regulatory mechanisms found in organisms nowadays.
Collapse
Affiliation(s)
- Katsushi Yokoyama
- National Institute of Advanced Industrial Science and Technology, AIST Tsukuba Center, Tsukuba, Japan
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Chen L, Brügger K, Skovgaard M, Redder P, She Q, Torarinsson E, Greve B, Awayez M, Zibat A, Klenk HP, Garrett RA. The genome of Sulfolobus acidocaldarius, a model organism of the Crenarchaeota. J Bacteriol 2005; 187:4992-9. [PMID: 15995215 PMCID: PMC1169522 DOI: 10.1128/jb.187.14.4992-4999.2005] [Citation(s) in RCA: 237] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sulfolobus acidocaldarius is an aerobic thermoacidophilic crenarchaeon which grows optimally at 80 degrees C and pH 2 in terrestrial solfataric springs. Here, we describe the genome sequence of strain DSM639, which has been used for many seminal studies on archaeal and crenarchaeal biology. The circular genome carries 2,225,959 bp (37% G+C) with 2,292 predicted protein-encoding genes. Many of the smaller genes were identified for the first time on the basis of comparison of three Sulfolobus genome sequences. Of the protein-coding genes, 305 are exclusive to S. acidocaldarius and 866 are specific to the Sulfolobus genus. Moreover, 82 genes for untranslated RNAs were identified and annotated. Owing to the probable absence of active autonomous and nonautonomous mobile elements, the genome stability and organization of S. acidocaldarius differ radically from those of Sulfolobus solfataricus and Sulfolobus tokodaii. The S. acidocaldarius genome contains an integrated, and probably encaptured, pARN-type conjugative plasmid which may facilitate intercellular chromosomal gene exchange in S. acidocaldarius. Moreover, it contains genes for a characteristic restriction modification system, a UV damage excision repair system, thermopsin, and an aromatic ring dioxygenase, all of which are absent from genomes of other Sulfolobus species. However, it lacks genes for some of their sugar transporters, consistent with it growing on a more limited range of carbon sources. These results, together with the many newly identified protein-coding genes for Sulfolobus, are incorporated into a public Sulfolobus database which can be accessed at http://dac.molbio.ku.dk/dbs/Sulfolobus.
Collapse
Affiliation(s)
- Lanming Chen
- Danish Archaea Centre, Institute of Molecular Biology, Copenhagen University
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Peeters E, Thia-Toong TL, Gigot D, Maes D, Charlier D. Ss-LrpB, a novel Lrp-like regulator of Sulfolobus solfataricus P2, binds cooperatively to three conserved targets in its own control region. Mol Microbiol 2005; 54:321-36. [PMID: 15469506 DOI: 10.1111/j.1365-2958.2004.04274.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Ss-LrpB, a novel Lrp-like DNA-binding protein from the hyperthermophilic crenarchaeon Sulfolobus solfataricus, was shown to bind cooperatively to three regularly spaced targets in its own control region, with as consensus the 15 bp palindrome 5'-TTGYAW WWWWTRCAA-3'. Binding to the border sites occurred with high affinity; the target in the middle proved to be a low affinity site which is stably bound only when both flanking sites are occupied. Ss-LrpB contacts two major groove segments and the intervening minor groove of each site, all aligned on one face of the helix. The operator shows intrinsic bending and is increasingly deformed upon binding of Ss-LrpB to one, two and three targets. Complex formation relies therefore on DNA conformability, protein-DNA and protein-protein contacts. Mobility-shift assays and in gel footprinting indicate that Ss-LrpB and the transcription factors TATA-box binding protein (TBP) and transcription factor B (TFB) can bind simultaneously to the control region. Based on these findings we present a model for the construction of the higher order nucleoprotein complexes and a hypothesis for the autoregulatory process. The latter is based on the concentration-dependent formation of distinct complexes exhibiting different stoichiometries and conformations, which could positively and negatively affect promoter activity.
Collapse
Affiliation(s)
- Eveline Peeters
- Erfelijkheidsleer en Microbiologie, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
| | | | | | | | | |
Collapse
|
31
|
Gregor D, Pfeifer F. In vivo analyses of constitutive and regulated promoters in halophilic archaea. MICROBIOLOGY-SGM 2005; 151:25-33. [PMID: 15632422 DOI: 10.1099/mic.0.27541-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The two gvpA promoters P(cA) and P(pA) of Halobacterium salinarum, and the P(mcA) promoter of Haloferax mediterranei were investigated with respect to growth-phase-dependent expression and regulation in Haloferax volcanii transformants using the bgaH reading frame encoding BgaH, an enzyme with beta-galactosidase activity, as reporter. For comparison, the P(fdx) promoter of the ferredoxin gene of Hbt. salinarum and the P(bgaH) promoter of Haloferax lucentense (formerly Haloferax alicantei) were analysed. P(fdx), driving the expression of a house-keeping gene, was highly active during the exponential growth phase, whereas P(bgaH) and the three gvpA promoters yielded the largest activities during the stationary growth phase. Compared to P(fdx), the basal promoter activities of P(pA) and P(mcA) were rather low, and larger activities were only detected in the presence of the endogenous transcriptional activator protein GvpE. The P(cA) promoter does not yield a detectable basal promoter activity and is only active in the presence of the homologous cGvpE. To investigate whether the P(cA)-TATA box and the BRE element were the reason for the lack of the basal P(cA) activity, these elements and also sequences further upstream were substituted with the respective sequences of the stronger P(pA) promoter and investigated in Hfx. volcanii transformants. All these promoter chimera did not yield a detectable basal promoter activity. However, whenever the P(pA)-BRE element was substituted for the P(cA)-BRE, an enhanced cGvpE-mediated activation was observed. The promoter chimeras harbouring P(pA)-BRE plus 5 (or more) bp further upstream also gained activation by the heterologous pGvpE and mcGvpE proteins. The sequence required for the GvpE-mediated activation was determined by a 4 bp scanning mutagenesis with the 45 bp region upstream of P(mcA)-BRE. None of these alterations influenced the basal promoter activity, but the sequence TGAAACGG-n4-TGAACCAA was important for the GvpE-mediated activation of P(mcA).
Collapse
Affiliation(s)
- Dagmar Gregor
- Institut für Mikrobiologie und Genetik, Technische Universität Darmstadt, Schnittspahnstr. 10, D-64287 Darmstadt, Germany
| | - Felicitas Pfeifer
- Institut für Mikrobiologie und Genetik, Technische Universität Darmstadt, Schnittspahnstr. 10, D-64287 Darmstadt, Germany
| |
Collapse
|
32
|
Hofacker A, Schmitz KM, Cichonczyk A, Sartorius-Neef S, Pfeifer F. GvpE- and GvpD-mediated transcription regulation of the p-gvp genes encoding gas vesicles in Halobacterium salinarum. Microbiology (Reading) 2004; 150:1829-1838. [PMID: 15184569 DOI: 10.1099/mic.0.27078-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The transcription of the 14 p-gvp genes involved in gas vesicle formation of Halobacterium salinarum PHH1 is driven by the four promoters pA, pD, pF and pO. The regulation of these promoters was investigated in Haloferax volcanii transformants with respect to the endogenous regulatory proteins GvpE and GvpD. Northern analyses demonstrated that the transcription derived from the pA and pD promoters was enhanced by GvpE, whereas the activities of the pF and pO promoters were not affected. Similar results were obtained using promoter fusions with the bgaH reporter gene encoding an enzyme with β-galactosidase activity. The largest amount of specific β-galactosidase activity was determined for pA-bgaH transformants, followed by pF-bgaH and pD-bgaH transformants. The presence of GvpE resulted in a severalfold induction of the pA and pD promoter, whereas the pF promoter was not affected. A lower GvpE-induced pA promoter activity was seen in the presence of GvpD in the pA-bgaH/DEex transformants, suggesting a function of GvpD in repression. To determine the DNA sequences involved in the GvpE-mediated activation, a 50-nucleotide region of the pA promoter was investigated by 4-nucleotide scanning mutagenesis. Some of these mutations affected the basal transcription, especially mutations in the region of the TATA box and the putative BRE sequence element, and also around position −10. Mutant E, harbouring a sequence with greater identity to the consensus BRE element, showed a significantly enhanced basal promoter activity compared to wild-type. Mutations not affecting basal transcription, but yielding a reduced GvpE-mediated activation, were located immediately upstream of BRE. These results suggested that the transcription activation by GvpE is in close contact with the core transcription machinery.
Collapse
Affiliation(s)
- Annette Hofacker
- Institut für Mikrobiologie und Genetik, Technische Universität Darmstadt, Schnittspahnstr. 10, D-64287 Darmstadt, Germany
| | - Kerstin-Maike Schmitz
- Institut für Mikrobiologie und Genetik, Technische Universität Darmstadt, Schnittspahnstr. 10, D-64287 Darmstadt, Germany
| | - Alexander Cichonczyk
- Institut für Mikrobiologie und Genetik, Technische Universität Darmstadt, Schnittspahnstr. 10, D-64287 Darmstadt, Germany
| | - Simone Sartorius-Neef
- Institut für Mikrobiologie und Genetik, Technische Universität Darmstadt, Schnittspahnstr. 10, D-64287 Darmstadt, Germany
| | - Felicitas Pfeifer
- Institut für Mikrobiologie und Genetik, Technische Universität Darmstadt, Schnittspahnstr. 10, D-64287 Darmstadt, Germany
| |
Collapse
|
33
|
Sun J, Klein A. A lysR-type regulator is involved in the negative regulation of genes encoding selenium-free hydrogenases in the archaeon Methanococcus voltae. Mol Microbiol 2004; 52:563-71. [PMID: 15066041 DOI: 10.1111/j.1365-2958.2004.03998.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The archaeon Methanococcus voltae encodes two pairs of NiFe-hydrogenase isoenzymes. One hydrogenase of each pair contains selenium in the active site, whereas the other one is selenium-free. The gene groups for the selenium-free hydrogenases, called vhc and frc, are linked by a common intergenic region. They are only transcribed under selenium limitation. A protein binding to a negative regulatory element involved in the regulation of the two operons was purified by DNA-affinity chromatography. Through the identification of the corresponding gene the protein was found to be a LysR-type regulator. It was named HrsM (hydrogenase gene regulator, selenium dependent in M. voltae). hrsM knockout mutants constitutively transcribed the vhc and frc operons in the presence of selenium. A putative HrsM binding site was also detected in the intergenic region in front of the hrsM gene. Northern blot analysis indicated that the hrsM gene might be autoregulated.
Collapse
Affiliation(s)
- Junsong Sun
- Genetics, Department of Biology, Philipps-University of Marburg, D-35032 Marburg, Germany
| | | |
Collapse
|
34
|
Zimmermann P, Pfeifer F. Regulation of the expression of gas vesicle genes in Haloferax mediterranei: interaction of the two regulatory proteins GvpD and GvpE. Mol Microbiol 2003; 49:783-94. [PMID: 12864859 DOI: 10.1046/j.1365-2958.2003.03593.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The gas vesicle formation in Haloferax mediterranei occurs in the stationary growth phase and involves the 14 genes mc-gvpACNO and mc-gvpDEFGHIJKLM. The appearance of the two regulatory proteins GvpD and GvpE, and also of GvpF, was investigated during the growth of H. mediterranei. GvpD was only found during the stationary growth phase, GvpE was present from the late exponential to stationary growth phase, and GvpF was present only during the exponential growth, although the three genes were co-transcribed. The impact of GvpD and GvpE on the activity of the promoter of the mc-gvpACNO gene cluster encoding the gas vesicle structural proteins was analysed in H. volcanii transformants containing the mc-gvpA gene or a fusion of the mcA promoter with the bgaH reading frame encoding a halobacterial beta-galactosidase as reporter. The experiments proved that GvpE is a transcriptional activator, whereas GvpD is involved in the repression. Protein-protein affinity chromatography was used to search for putative binding partners of GvpD and GvpE. Both proteins were synthesized in Escherichia coli as his-tagged proteins, isolated under denaturing conditions and refolded by dialysis against buffers containing decreasing urea and increasing KCl concentrations up to 2.5 M. The Ni-NTA matrix tagged with GvpD-his or GvpE-his was incubated with soluble proteins of gas vesicle producing H. mediterranei cells. A 21 kDa protein was purified using the matrix tagged with GvpD-his which proved to be GvpE by Western analysis. Vice versa, GvpD was purified using the GvpE-his-Ni-NTA matrix. These results strongly suggested that GvpD and GvpE were able to interact and might constitute a regulatory system.
Collapse
Affiliation(s)
- Peter Zimmermann
- Institut für Mikrobiologie und Genetik, Technische Universität Darmstadt, Darmstadt, Germany
| | | |
Collapse
|
35
|
Abstract
Genome analysis has revealed that members of the Lrp family of transcriptional regulators are widely distributed among prokaryotes, both bacteria and archaea. The archetype Leucine-responsive Regulatory Protein from Escherichia coli is a global regulator involved in modulating a variety of metabolic functions, including the catabolism and anabolism of amino acids as well as pili synthesis. Most Lrp homologues, however, appear to act as specific regulators of amino acid metabolism-related genes. Like most prokaryotic transcriptional regulators, Lrp-like regulators consist of a DNA-binding domain and a ligand-binding domain. The crystal structure of the Pyrococcus furiosus LrpA revealed an N-terminal domain with a common helix-turn-helix fold, and a C-terminal domain with a typical alphabeta-sandwich fold. The latter regulatory domain constitutes a novel ligand-binding site and has been designated RAM. Database analysis reveals that the RAM domain is present in many prokaryotic genomes, potentially encoding (1) Lrp-homologues, when fused to a DNA-binding domain (2) enzymes, when fused as a potential regulatory domain to a catalytic domain, and (3) stand-alone RAM modules with unknown function. The architecture of Lrp regulators with two distinct domains that harbour the regulatory (effector-binding) site and the active (DNA-binding) site, and their separation by a flexible hinge region, suggests a general allosteric switch of Lrp-like regulators.
Collapse
Affiliation(s)
- Arie B Brinkman
- Laboratory of Microbiology, Wageningen University, Hesselink van Suchtelenweg 4, NL-6307 CT Wageningen, The Netherlands
| | | | | | | |
Collapse
|
36
|
Lee SJ, Engelmann A, Horlacher R, Qu Q, Vierke G, Hebbeln C, Thomm M, Boos W. TrmB, a sugar-specific transcriptional regulator of the trehalose/maltose ABC transporter from the hyperthermophilic archaeon Thermococcus litoralis. J Biol Chem 2003; 278:983-90. [PMID: 12426307 DOI: 10.1074/jbc.m210236200] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report the characterization of TrmB, a protein of 38,800 apparent molecular weight, that is involved in the maltose-specific regulation of a gene cluster in Thermococcus litoralis, malE malF malG orf trmB malK, encoding a binding protein-dependent ABC transporter for trehalose and maltose. TrmB binds maltose and trehalose half-maximally at 20 microm and 0.5 mm sugar concentration, respectively. Binding of maltose but not of trehalose showed indications of sigmoidality and quenched the intrinsic tryptophan fluorescence by 15%, indicating a conformational change on maltose binding. TrmB causes a shift in electrophoretic mobility of DNA fragments harboring the promoter and upstream regulatory motif identified by footprinting. Band shifting by TrmB can be prevented by maltose. In vitro transcription assays with purified components from Pyrococcus furiosus have been established to show pmalE promoter-dependent transcription at 80 degrees C. TrmB specifically inhibits transcription, and this inhibition is counteracted by maltose and trehalose. These data characterize TrmB as a maltose-specific repressor for the trehalose/maltose transport operon of Thermococcus litoralis.
Collapse
Affiliation(s)
- Sung-Jae Lee
- Department of Biology, University of Konstanz, Germany
| | | | | | | | | | | | | | | |
Collapse
|
37
|
Enoru-Eta J, Gigot D, Glansdorff N, Charlier D. High resolution contact probing of the Lrp-like DNA-binding protein Ss-Lrp from the hyperthermoacidophilic crenarchaeote Sulfolobus solfataricus P2. Mol Microbiol 2002; 45:1541-55. [PMID: 12354224 DOI: 10.1046/j.1365-2958.2002.03136.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Ss-Lrp, from Sulfolobus solfataricus, is an archaeal homologue of the global bacterial regulator Lrp (Leucine-responsive regulatory protein), which out of all genome-encoded proteins is most similar to Escherichia coli Lrp (E-value of 5.6 e-14). The recombinant protein has been purified as a 68 kDa homotetramer. The specific binding of Ss-Lrp to its own control region is suggestive of negative autoregulation. A high resolution contact map of Ss-Lrp binding was established by DNase I and hydroxyl radical footprinting, small non-intercalating groove-specific ligand-binding interference, and various base-specific premodification and base removal binding interference techniques. We show that Ss-Lrp binds one face of the DNA helix and establishes the most salient contacts with two major groove segments and the intervening minor groove, in a region that overlaps the TATA-box and BRE promoter elements. Therefore, Ss-Lrp most likely exerts autoregulation by preventing promoter recognition by TBP and TFB. Moreover, the results demonstrate profound Ss-Lrp induced structural alterations of sequence stretches flanking the core contact site, and reveal that the deformability of these regions significantly contributes to binding selectivity.
Collapse
Affiliation(s)
- Julius Enoru-Eta
- Erfelijkheidsleer en Microbiologie, Vrije Universiteit Brussels, Belgium
| | | | | | | |
Collapse
|
38
|
Brinkman AB, Bell SD, Lebbink RJ, de Vos WM, van der Oost J. The Sulfolobus solfataricus Lrp-like protein LysM regulates lysine biosynthesis in response to lysine availability. J Biol Chem 2002; 277:29537-49. [PMID: 12042311 DOI: 10.1074/jbc.m203528200] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although the archaeal transcription apparatus resembles the eukaryal RNA polymerase II system, many bacterial-like regulators can be found in archaea. Particularly, all archaeal genomes sequenced to date contain genes encoding homologues of Lrp (leucine-responsive regulatory protein). Whereas Lrp-like proteins in bacteria are involved in regulation of amino acid metabolism, their physiological role in archaea is unknown. Although several archaeal Lrp-like proteins have been characterized recently, no target genes apart from their own coding genes have been discovered yet, and no ligands for these regulators have been identified so far. In this study, we show that the Lrp-like protein LysM from Sulfolobus solfataricus is involved in the regulation of lysine and possibly also arginine biosynthesis, encoded by the lys gene cluster. Exogenous lysine is the regulatory signal for lys gene expression and specifically serves as a ligand for LysM by altering its DNA binding affinity. LysM binds directly upstream of the TFB-responsive element of the intrinsically weak lysW promoter, and DNA binding is favored in the absence of lysine, when lysWXJK transcription is maximal. The combined in vivo and in vitro data are most compatible with a model in which the bacterial-like LysM activates the eukarya-like transcriptional machinery. As with transcriptional activation by Escherichia coli Lrp, activation by LysM is apparently dependent on a co-activator, which remains to be identified.
Collapse
Affiliation(s)
- Arie B Brinkman
- Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University, Hesselink van Suchtelenweg 4, 6703 CT Wageningen, The Netherlands.
| | | | | | | | | |
Collapse
|
39
|
Thia-Toong TL, Roovers M, Durbecq V, Gigot D, Glansdorff N, Charlier D. Genes of de novo pyrimidine biosynthesis from the hyperthermoacidophilic crenarchaeote Sulfolobus acidocaldarius: novel organization in a bipolar operon. J Bacteriol 2002; 184:4430-41. [PMID: 12142413 PMCID: PMC135248 DOI: 10.1128/jb.184.16.4430-4441.2002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2002] [Accepted: 05/31/2002] [Indexed: 11/20/2022] Open
Abstract
Sequencing a 8,519-bp segment of the Sulfolobus acidocaldarius genome revealed the existence of a tightly packed bipolar pyrimidine gene cluster encoding the enzymes of de novo UMP synthesis. The G+C content of 35.3% is comparable to that of the entire genome, but intergenic regions exhibit a considerably lower percentage of strong base pairs. Coding regions harbor the classical excess of purines on the coding strand, whereas intergenic regions do not show this bias. Reverse transcription-PCR and primer extension experiments demonstrated the existence of two polycistronic messengers, pyrEF-orf8 and pyrBI-orf1-pyrCD-orf2-orf3-orf4, initiated from a pair of divergent and partially overlapping promoters. The gene order and the grouping in two wings of a bipolar operon constitute a novel organization of pyr genes that also occurs in the recently determined genome sequences of Sulfolobus solfataricus P2 and Sulfolobus tokodaii strain 7; the configuration appears therefore characteristic of Sulfolobus. The quasi-leaderless pyrE and pyrB genes do not bear a Shine-Dalgarno sequence, whereas the initiation codon of promoter-distal genes is preceded at an appropriate distance by a sequence complementary to the 3' end of 16S rRNA. The polycistronic nature of the pyr messengers and the existence of numerous overlaps between contiguous open reading frames suggests the existence of translational coupling. pyrB transcription was shown to be approximately twofold repressed in the presence of uracil. The mechanism underlying this modulation is as yet unknown, but it appears to be of a type different from the various attenuation-like mechanisms that regulate pyrB transcription in bacteria. In contrast, the pyrE-pyrB promoter/control region harbors direct repeats and imperfect palindromes reminiscent of target sites for the binding of a hypothetical regulatory protein(s).
Collapse
Affiliation(s)
- Thia-Lin Thia-Toong
- Erfelijkheidsleer en Microbiologie, Vrije Universiteit Brussel, B-1070 Brussels, Belgium
| | | | | | | | | | | |
Collapse
|
40
|
Affiliation(s)
- J Soppa
- Institute for Microbiology, Biocentre Niederursel, J. W. Goethe University Frankfurt, D-60439 Frankfurt, Germany
| |
Collapse
|
41
|
Dahlke I, Thomm M. A Pyrococcus homolog of the leucine-responsive regulatory protein, LrpA, inhibits transcription by abrogating RNA polymerase recruitment. Nucleic Acids Res 2002; 30:701-10. [PMID: 11809882 PMCID: PMC100285 DOI: 10.1093/nar/30.3.701] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The genomes of Archaea harbor homologs of the global bacterial regulator leucine-responsive regulatory protein (Lrp). Archaeal Lrp homologs are helix-turn-helix DNA-binding proteins that specifically repress the transcription of their own genes in vitro. Here, we analyze the interaction of Pyrococcus LrpA with components of the archaeal transcriptional machinery at the lrpA promoter. DNA-protein complexes can be isolated by electrophoretic mobility shift assays that contain both LrpA and the two archaeal transcription factors TBP and TFB. Phenanthroline-copper footprinting experiments showed that the DNA-binding sites of LrpA and TBP/TFB do not overlap. These results and the finding that association of RNA polymerase with the TBP-TFB promoter complex was inhibited in the presence of LrpA indicate that Pyrococcus LrpA interferes with RNA polymerase recruitment. A DNA motif required for the LrpA-DNA interaction was inferred from dimethylsulfate methylation interference experiments.
Collapse
Affiliation(s)
- Isabell Dahlke
- Institut für Allgemeine Mikrobiologie, Universität Kiel, Am Botanischen Garten 1-9, 24118 Kiel, Germany
| | | |
Collapse
|
42
|
Napoli A, Kvaratskelia M, White MF, Rossi M, Ciaramella M. A novel member of the bacterial-archaeal regulator family is a nonspecific dna-binding protein and induces positive supercoiling. J Biol Chem 2001; 276:10745-52. [PMID: 11148211 DOI: 10.1074/jbc.m010611200] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In hyperthermophilic Archaea genomic DNA is from relaxed to positively supercoiled in vivo because of the action of the enzyme reverse gyrase, and this peculiarity is believed to be related to stabilization of DNA against denaturation. We report the identification and characterization of Smj12, a novel protein of Sulfolobus solfataricus, which is homologous to members of the so-called Bacterial-Archaeal family of regulators, found in multiple copies in Eubacteria and Archaea. Whereas other members of the family are sequence-specific DNA- binding proteins and have been implicated in transcriptional regulation, Smj12 is a nonspecific DNA-binding protein that stabilizes the double helix and induces positive supercoiling. Smj12 is not abundant, suggesting that it is not a general architectural protein, but rather has a specialized function and/or localization. Smj12 is the first protein with the described features identified in Archaea and might participate in control of superhelicity during DNA transactions.
Collapse
Affiliation(s)
- A Napoli
- Institute of Protein Biochemistry and Enzymology, Consiglio Nazionale delle Ricerche, Via Marconi 10, 80125 Naples, Italy
| | | | | | | | | |
Collapse
|
43
|
Abstract
The archaeal basal transcription machinery resembles the core components of the eucaryal RNA polymerase II apparatus. Thus, studies of the archaeal basal machinery over the last few years have shed light on fundamentally conserved aspects of the mechanisms of transcription pre-initiation complex assembly in both eucarya and archaea. Intriguingly, it has become increasingly apparent that regulators of archaeal transcription resemble regulators initially identified in bacteria. The presence of these shared bacterial-archaeal regulators has given insight into the evolution of gene regulatory processes in all three domains of life.
Collapse
Affiliation(s)
- S D Bell
- Wellcome Trust and Cancer Research Campaign Institute of Cancer and Developmental Biology and Department of Zoology, University of Cambridge, Tennis Court Road, CB2 1QR, Cambridge, UK.
| | | |
Collapse
|
44
|
Ouhammouch M, Geiduschek EP. A thermostable platform for transcriptional regulation: the DNA-binding properties of two Lrp homologs from the hyperthermophilic archaeon Methanococcus jannaschii. EMBO J 2001; 20:146-56. [PMID: 11226165 PMCID: PMC140199 DOI: 10.1093/emboj/20.1.146] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The hyperthermophilic archaeon Methanococcus jannaschii encodes two putative transcription regulators, Ptr1 and Ptr2, related to the bacterial Lrp/AsnC family of transcriptional regulators. We show that these two small helix-turn-helix proteins are specific DNA-binding proteins recognizing sites in their respective promoter regions. In vitro selection at high temperature has been used to isolate sets of high- affinity DNA sites that define a palindromic consensus binding sequence for each protein. Ptr1 and Ptr2 bind these cognate sites from one side of the DNA helix, as dimers, with each protein monomer making base- specific contacts in the major groove. As the first archaeal DNA-binding proteins with clearly defined specificities, Ptr1 and Ptr2 provide a thermostable DNA-binding platform for analysis of effector interactions with the core archaeal transcription apparatus; a platform allowing manipulation of promoter structure and examination of mechanisms of action at heterologous promoters.
Collapse
Affiliation(s)
- M Ouhammouch
- Division of Biology and Center for Molecular Genetics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0634, USA.
| | | |
Collapse
|