1
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Blombach F, Werner F. Chromatin and gene regulation in archaea. Mol Microbiol 2024. [PMID: 39096085 DOI: 10.1111/mmi.15302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Revised: 07/12/2024] [Accepted: 07/16/2024] [Indexed: 08/04/2024]
Abstract
The chromatinisation of DNA by nucleoid-associated proteins (NAPs) in archaea 'formats' the genome structure in profound ways, revealing both striking differences and analogies to eukaryotic chromatin. However, the extent to which archaeal NAPs actively regulate gene expression remains poorly understood. The dawn of quantitative chromatin mapping techniques and first NAP-specific occupancy profiles in different archaea promise a more accurate view. A picture emerges where in diverse archaea with very different NAP repertoires chromatin maintains access to regulatory motifs including the gene promoter independently of transcription activity. Our re-analysis of genome-wide occupancy data of the crenarchaeal NAP Cren7 shows that these chromatin-free regions are flanked by increased Cren7 binding across the transcription start site. While bacterial NAPs often form heterochromatin-like regions across islands with xenogeneic genes that are transcriptionally silenced, there is little evidence for similar structures in archaea and data from Haloferax show that the promoters of xenogeneic genes remain accessible. Local changes in chromatinisation causing wide-ranging effects on transcription restricted to one chromosomal interaction domain (CID) in Saccharolobus islandicus hint at a higher-order level of organisation between chromatin and transcription. The emerging challenge is to integrate results obtained at microscale and macroscale, reconciling molecular structure and function with dynamic genome-wide chromatin landscapes.
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Affiliation(s)
- Fabian Blombach
- Division of Biosciences, RNAP Laboratory, Institute of Structural and Molecular Biology (ISMB), University College London, London, UK
| | - Finn Werner
- Division of Biosciences, RNAP Laboratory, Institute of Structural and Molecular Biology (ISMB), University College London, London, UK
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2
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Özer H, Wasser D, Sandner L, Soppa J. Intermolecular Gene Conversion for the Equalization of Genome Copies in the Polyploid Haloarchaeon Haloferax volcanii: Identification of Important Proteins. Genes (Basel) 2024; 15:861. [PMID: 39062640 PMCID: PMC11276520 DOI: 10.3390/genes15070861] [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: 05/10/2024] [Revised: 06/18/2024] [Accepted: 06/20/2024] [Indexed: 07/28/2024] Open
Abstract
The model haloarchaeon Haloferax volcanii is polyploid with about 20 copies of its major chromosome. Recently it has been described that highly efficient intermolecular gene conversion operates in H. volcanii to equalize the chromosomal copies. In the current study, 24 genes were selected that encode proteins with orthologs involved in gene conversion or homologous recombination in archaea, bacteria, or eukaryotes. Single gene deletion strains of 22 genes and a control gene were constructed in two parent strains for a gene conversion assay; only radA and radB were shown to be essential. Protoplast fusions were used to generate strains that were heterozygous for the gene HVO_2528, encoding an enzyme for carotinoid biosynthesis. It was revealed that a lack of six of the proteins did not influence the efficiency of gene conversion, while sixteen mutants had severe gene conversion defects. Notably, lack of paralogous proteins of gene families had very different effects, e.g., mutant Δrad25b had no phenotype, while mutants Δrad25a, Δrad25c, and Δrad25d were highly compromised. Generation of a quadruple rad25 and a triple sph deletion strain also indicated that the paralogs have different functions, in contrast to sph2 and sph4, which cannot be deleted simultaneously. There was no correlation between the severity of the phenotypes and the respective transcript levels under non-stressed conditions, indicating that gene expression has to be induced at the onset of gene conversion. Phylogenetic trees of the protein families Rad3/25, MutL/S, and Sph/SMC/Rad50 were generated to unravel the history of the paralogous proteins of H. volcanii. Taken together, unselected intermolecular gene conversion in H. volcanii involves at least 16 different proteins, the molecular roles of which can be studied in detail in future projects.
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Affiliation(s)
| | | | | | - Jörg Soppa
- Biocentre, Institute for Molecular Biosciences, Goethe University, Max-von-Laue-Str. 9, D-60439 Frankfurt, Germany; (H.Ö.); (D.W.); (L.S.)
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3
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Gulati P, Singh A, Patra S, Bhat S, Verma A. Restriction modification systems in archaea: A panoramic outlook. Heliyon 2024; 10:e27382. [PMID: 38644887 PMCID: PMC11033074 DOI: 10.1016/j.heliyon.2024.e27382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 02/19/2024] [Accepted: 02/28/2024] [Indexed: 04/23/2024] Open
Abstract
Restriction modification (RM) systems are one of the ubiquitous yet primitive defense responses employed by bacteria and archaea with the primary role of safeguarding themselves against invading bacteriophages. Protection of the host occurs by the cleavage of the invading foreign DNA via restriction endonucleases with concomitant methylation of host DNA with the aid of a methyltransferase counterpart. RM systems have been extensively studied in bacteria, however, in the case of archaea there are limited reports of RM enzymes that are investigated to date owing to their inhospitable growth demands. This review aims to broaden the knowledge about what is known about the diversity of RM systems in archaea and encapsulate the current knowledge on restriction and modification enzymes characterized in archaea so far and the role of RM systems in the milieu of archaeal biology.
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Affiliation(s)
- Pallavi Gulati
- Department of Microbiology, Ram Lal Anand College, University of Delhi South Campus, New Delhi 110021, India
| | - Ashish Singh
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India
| | - Sandeep Patra
- Department of Microbiology, Ram Lal Anand College, University of Delhi South Campus, New Delhi 110021, India
| | - Shreyas Bhat
- Department of Microbiology, Ram Lal Anand College, University of Delhi South Campus, New Delhi 110021, India
| | - Anil Verma
- Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA-15213, USA
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4
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Martinez Pastor M, Sakrikar S, Hwang S, Hackley R, Soborowski A, Maupin-Furlow J, Schmid A. TroR is the primary regulator of the iron homeostasis transcription network in the halophilic archaeon Haloferax volcanii. Nucleic Acids Res 2024; 52:125-140. [PMID: 37994787 PMCID: PMC10783522 DOI: 10.1093/nar/gkad997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 10/10/2023] [Accepted: 10/23/2023] [Indexed: 11/24/2023] Open
Abstract
Maintaining the intracellular iron concentration within the homeostatic range is vital to meet cellular metabolic needs and reduce oxidative stress. Previous research revealed that the haloarchaeon Halobacterium salinarum encodes four diphtheria toxin repressor (DtxR) family transcription factors (TFs) that together regulate the iron response through an interconnected transcriptional regulatory network (TRN). However, the conservation of the TRN and the metal specificity of DtxR TFs remained poorly understood. Here we identified and characterized the TRN of Haloferax volcanii for comparison. Genetic analysis demonstrated that Hfx. volcanii relies on three DtxR transcriptional regulators (Idr, SirR, and TroR), with TroR as the primary regulator of iron homeostasis. Bioinformatics and molecular approaches revealed that TroR binds a conserved cis-regulatory motif located ∼100 nt upstream of the start codon of iron-related target genes. Transcriptomics analysis demonstrated that, under conditions of iron sufficiency, TroR repressed iron uptake and induced iron storage mechanisms. TroR repressed the expression of one other DtxR TF, Idr. This reduced DtxR TRN complexity relative to that of Hbt. salinarum appeared correlated with natural variations in iron availability. Based on these data, we hypothesize that variable environmental conditions such as iron availability appear to select for increasing TRN complexity.
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Affiliation(s)
| | - Saaz Sakrikar
- Center for Genomics and System Biology at NYU Department of Biology, New York University, NY, NY 10003, USA
| | - Sungmin Hwang
- Division of Practical Research, Honam National Institute of Biological Resources, Jeollanam-do, Mokpo-si 58762, Republic of Korea
| | - Rylee K Hackley
- Department of Biology, Duke University, Durham, NC 27708, USA
- University Program in Genetics and Genomics, Duke University, Durham, NC 27708, USA
| | - Andrew L Soborowski
- Department of Biology, Duke University, Durham, NC 27708, USA
- Computational Biology and Bioinformatics graduate program, Duke University, Durham, NC 27708, USA
| | - Julie A Maupin-Furlow
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
- Genetics Institute, University of Florida, Gainesville, FL 32611, USA
| | - Amy K Schmid
- Department of Biology, Duke University, Durham, NC 27708, USA
- University Program in Genetics and Genomics, Duke University, Durham, NC 27708, USA
- Computational Biology and Bioinformatics graduate program, Duke University, Durham, NC 27708, USA
- Center for Genomics and Computational Biology, Duke University, Durham, NC 27708, USA
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Zhao D, Zhang S, Chen J, Zhao J, An P, Xiang H. Members of the class Candidatus Ordosarchaeia imply an alternative evolutionary scenario from methanogens to haloarchaea. THE ISME JOURNAL 2024; 18:wrad033. [PMID: 38366248 PMCID: PMC10873845 DOI: 10.1093/ismejo/wrad033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 12/05/2023] [Accepted: 12/19/2023] [Indexed: 02/18/2024]
Abstract
The origin of methanogenesis can be traced to the common ancestor of non-DPANN archaea, whereas haloarchaea (or Halobacteria) are believed to have evolved from a methanogenic ancestor through multiple evolutionary events. However, due to the accelerated evolution and compositional bias of proteins adapting to hypersaline habitats, Halobacteria exhibit substantial evolutionary divergence from methanogens, and the identification of the closest methanogen (either Methanonatronarchaeia or other taxa) to Halobacteria remains a subject of debate. Here, we obtained five metagenome-assembled genomes with high completeness from soda-saline lakes on the Ordos Plateau in Inner Mongolia, China, and we proposed the name Candidatus Ordosarchaeia for this novel class. Phylogenetic analyses revealed that Ca. Ordosarchaeia is firmly positioned near the median position between the Methanonatronarchaeia and Halobacteria-Hikarchaeia lineages. Functional predictions supported the transitional status of Ca. Ordosarchaeia with the metabolic potential of nonmethanogenic and aerobic chemoheterotrophy, as did remnants of the gene sequences of methylamine/dimethylamine/trimethylamine metabolism and coenzyme M biosynthesis. Based on the similarity of the methyl-coenzyme M reductase genes mcrBGADC in Methanonatronarchaeia with the phylogenetically distant methanogens, an alternative evolutionary scenario is proposed, in which Methanonatronarchaeia, Ca. Ordosarchaeia, Ca. Hikarchaeia, and Halobacteria share a common ancestor that initially lost mcr genes. However, certain members of Methanonatronarchaeia subsequently acquired mcr genes through horizontal gene transfer from distantly related methanogens. This hypothesis is supported by amalgamated likelihood estimation, phylogenetic analysis, and gene arrangement patterns. Altogether, Ca. Ordosarchaeia genomes clarify the sisterhood of Methanonatronarchaeia with Halobacteria and provide new insights into the evolution from methanogens to haloarchaea.
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Affiliation(s)
- Dahe Zhao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Shengjie Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 101408, China
| | - Junyu Chen
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Juanjuan Zhao
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Peng An
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, Sichuan Normal University, Sichuan 610068, China
| | - Hua Xiang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing 101408, China
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Buda DM, Szekeres E, Tudoran LB, Esclapez J, Banciu HL. Genome-wide transcriptional response to silver stress in extremely halophilic archaeon Haloferax alexandrinus DSM 27206 T. BMC Microbiol 2023; 23:381. [PMID: 38049746 PMCID: PMC10694973 DOI: 10.1186/s12866-023-03133-z] [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: 10/16/2023] [Accepted: 11/22/2023] [Indexed: 12/06/2023] Open
Abstract
BACKGROUND The extremely halophilic archaeon Haloferax (Hfx.) alexandrinus DSM 27206 T was previously documented for the ability to biosynthesize silver nanoparticles while mechanisms underlying its silver tolerance were overlooked. In the current study, we aimed to assess the transcriptional response of this haloarchaeon to varying concentrations of silver, seeking a comprehensive understanding of the molecular determinants underpinning its heavy metal tolerance. RESULTS The growth curves confirmed the capacity of Hfx. alexandrinus to surmount silver stress, while the SEM-EDS analysis illustrated the presence of silver nanoparticles in cultures exposed to 0.5 mM silver nitrate. The RNA-Seq based transcriptomic analysis of Hfx. alexandrinus cells exposed to 0.1, 0.25, and 0.5 mM silver nitrate revealed the differential expression of multiple sets of genes potentially employed in heavy-metal stress response, genes mostly related to metal transporters, basic metabolism, oxidative stress response and cellular motility. The RT-qPCR analysis of selected transcripts was conducted to verify and validate the generated RNA-Seq data. CONCLUSIONS Our results indicated that copA, encoding the copper ATPase, is essential for the survival of Hfx. alexandrinus cells in silver-containing saline media. The silver-exposed cultures underwent several metabolic adjustments that enabled the activation of enzymes involved in the oxidative stress response and impairment of the cellular movement capacity. To our knowledge, this study represents the first comprehensive analysis of gene expression in halophillic archaea facing increased levels of heavy metals.
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Grants
- PN-III-P4-ID-PCE-2020-1559 Ministry of Research, Innovation and Digitization, CNCS/CCCDI - UEFISCD
- PN-III-P4-ID-PCE-2020-1559 Ministry of Research, Innovation and Digitization, CNCS/CCCDI - UEFISCD
- PN-III-P4-ID-PCE-2020-1559 Ministry of Research, Innovation and Digitization, CNCS/CCCDI - UEFISCD
- PN-III-P4-ID-PCE-2020-1559 Ministry of Research, Innovation and Digitization, CNCS/CCCDI - UEFISCD
- VIGRO-016 Vicerrectorado de Investigación y Transferencia de Conocimiento of the University of Alicante
- Ministry of Research, Innovation and Digitization, CNCS/CCCDI – UEFISCD
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Affiliation(s)
- Doriana Mădălina Buda
- Doctoral School of Integrative Biology, Faculty of Biology and Geology, Babeș-Bolyai University, Cluj-Napoca, Romania.
- Department of Molecular Biology and Biotechnology, Babeș-Bolyai University, Cluj-Napoca, Romania.
| | - Edina Szekeres
- Institute of Biological Research Cluj, NIRDBS, Cluj-Napoca, Romania
- Centre for Systems Biology, Biodiversity and Bioresources, Babeș-Bolyai University, Cluj-Napoca, Romania
| | - Lucian Barbu Tudoran
- Department of Molecular Biology and Biotechnology, Babeș-Bolyai University, Cluj-Napoca, Romania
- National Institute for Research and Development of Isotopic and Molecular Technologies, Cluj-Napoca, Romania
| | - Julia Esclapez
- Biochemistry and Molecular Biology and Soil and Agricultural Chemistry Department, Biochemistry and Molecular Biology Area, Faculty of Science, University of Alicante, Alicante, Spain
| | - Horia Leonard Banciu
- Department of Molecular Biology and Biotechnology, Babeș-Bolyai University, Cluj-Napoca, Romania.
- Emil G. Racoviță Institute, Babeș-Bolyai University, Cluj-Napoca, Romania.
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7
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Marinov GK, Bagdatli ST, Wu T, He C, Kundaje A, Greenleaf WJ. The chromatin landscape of the euryarchaeon Haloferax volcanii. Genome Biol 2023; 24:253. [PMID: 37932847 PMCID: PMC10626798 DOI: 10.1186/s13059-023-03095-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 10/24/2023] [Indexed: 11/08/2023] Open
Abstract
BACKGROUND Archaea, together with Bacteria, represent the two main divisions of life on Earth, with many of the defining characteristics of the more complex eukaryotes tracing their origin to evolutionary innovations first made in their archaeal ancestors. One of the most notable such features is nucleosomal chromatin, although archaeal histones and chromatin differ significantly from those of eukaryotes, not all archaea possess histones and it is not clear if histones are a main packaging component for all that do. Despite increased interest in archaeal chromatin in recent years, its properties have been little studied using genomic tools. RESULTS Here, we adapt the ATAC-seq assay to archaea and use it to map the accessible landscape of the genome of the euryarchaeote Haloferax volcanii. We integrate the resulting datasets with genome-wide maps of active transcription and single-stranded DNA (ssDNA) and find that while H. volcanii promoters exist in a preferentially accessible state, unlike most eukaryotes, modulation of transcriptional activity is not associated with changes in promoter accessibility. Applying orthogonal single-molecule footprinting methods, we quantify the absolute levels of physical protection of H. volcanii and find that Haloferax chromatin is similarly or only slightly more accessible, in aggregate, than that of eukaryotes. We also evaluate the degree of coordination of transcription within archaeal operons and make the unexpected observation that some CRISPR arrays are associated with highly prevalent ssDNA structures. CONCLUSIONS Our results provide the first comprehensive maps of chromatin accessibility and active transcription in Haloferax across conditions and thus a foundation for future functional studies of archaeal chromatin.
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Affiliation(s)
- Georgi K Marinov
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA.
| | - S Tansu Bagdatli
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA
| | - Tong Wu
- Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL, 60637, USA
| | - Chuan He
- Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL, 60637, USA
- Department of Biochemistry and Molecular Biology and Institute for Biophysical Dynamics, The University of Chicago, Chicago, IL, 60637, USA
- Howard Hughes Medical Institute, The University of Chicago, Chicago, IL, 60637, USA
| | - Anshul Kundaje
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA
- Department of Computer Science, Stanford University, Stanford, CA, 94305, USA
| | - William J Greenleaf
- Department of Genetics, Stanford University, Stanford, CA, 94305, USA
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA, 94305, USA
- Department of Applied Physics, Stanford University, Stanford, CA, 94305, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
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8
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Patro M, Duggin IG, Albers SV, Ithurbide S. "Influence of plasmids, selection markers and auxotrophic mutations on Haloferax volcanii cell shape plasticity". Front Microbiol 2023; 14:1270665. [PMID: 37840741 PMCID: PMC10570808 DOI: 10.3389/fmicb.2023.1270665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 09/11/2023] [Indexed: 10/17/2023] Open
Abstract
Haloferax volcanii and other Haloarchaea can be pleomorphic, adopting different shapes, which vary with growth stages. Several studies have shown that H. volcanii cell shape is sensitive to various external factors including growth media and physical environment. In addition, several studies have noticed that the presence of a recombinant plasmid in the cells is also a factor impacting H. volcanii cell shape, notably by favoring the development of rods in early stages of growth. Here we investigated the reasons for this phenomenon by first studying the impact of auxotrophic mutations on cell shape in strains that are commonly used as genetic backgrounds for selection during strain engineering (namely: H26, H53, H77, H98, and H729) and secondly, by studying the effect of the presence of different plasmids containing selection markers on the cell shape of these strains. Our study showed that most of these auxotrophic strains have variation in cell shape parameters including length, aspect ratio, area and circularity and that the plasmid presence is impacting these parameters too. Our results indicated that ΔhdrB strains and hdrB selection markers have the most influence on H. volcanii cell shape, in addition to the sole presence of a plasmid. Finally, we discuss limitations in studying cell shape in H. volcanii and make recommendations based on our results for improving reproducibility of such studies.
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Affiliation(s)
- Megha Patro
- Molecular Biology of Archaea, Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Spemann Graduate School of Biology and Medicine, University of Freiburg, Freiburg, Germany
| | - Iain G. Duggin
- The Australian Institute for Microbiology and Infection, University of Technology Sydney, Sydney, NSW, Australia
| | - Sonja-Verena Albers
- Molecular Biology of Archaea, Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Solenne Ithurbide
- Molecular Biology of Archaea, Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
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Rados T, Andre K, Cerletti M, Bisson A. A sweet new set of inducible and constitutive promoters in Haloferax volcanii. Front Microbiol 2023; 14:1204876. [PMID: 37637112 PMCID: PMC10448506 DOI: 10.3389/fmicb.2023.1204876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 07/27/2023] [Indexed: 08/29/2023] Open
Abstract
Inducible promoters are one of cellular and molecular biology's most important technical tools. The ability to deplete, replete, and overexpress genes on demand is the foundation of most functional studies. Here, we developed and characterized a new xylose-responsive promoter (Pxyl), the second inducible promoter system for the model haloarcheon Haloferax volcanii. Generating RNA-seq datasets from cultures in the presence of four historically used inducers (arabinose, xylose, maltose, and IPTG), we mapped upregulated genomic regions primarily repressed in the absence of the above inducers. We found a highly upregulated promoter that controls the expression of the xacEA (HVO_B0027-28) operon in the pHV3 chromosome. To characterize this promoter region, we cloned msfGFP (monomeric superfold green fluorescent protein) under the control of two upstream regions into a modified pTA962 vector: the first 250 bp (P250) and the whole 750 bp intergenic fragments (P750). The P250 sequence drove the expression of msfGFP constitutively, and its expression did not respond to the presence or absence of xylose. However, the P750 promoter showed not only to be repressed in the absence of xylose but also expressed higher levels of msfGFP than the previously described inducible promoter PtnaA in the presence of the inducer. Finally, we validated the inducible Pxyl promoter by reproducing morphological phenotypes already described in the literature. By overexpressing the tubulin-like FtsZ1 and FtsZ2, we observed similar but slightly more pronounced morphological defects than the tryptophan-inducible promoter PtnaA. FtsZ1 overexpression created larger, deformed cells, whereas cells overexpressing FtsZ2 were smaller but mostly retained their shape. In summary, this work contributes a new xylose-inducible promoter that could be used simultaneously with the well-established PtnaA in functional studies in H. volcanii in the future.
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Affiliation(s)
- Theopi Rados
- Department of Biology, Brandeis University, Waltham, MA, United States
| | - Katherine Andre
- Department of Biology, Brandeis University, Waltham, MA, United States
| | - Micaela Cerletti
- Department of Biology, Brandeis University, Waltham, MA, United States
- Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Mar del Plata, Argentina
| | - Alex Bisson
- Department of Biology, Brandeis University, Waltham, MA, United States
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10
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Xu T, Tao X, He H, Kempher ML, Zhang S, Liu X, Wang J, Wang D, Ning D, Pan C, Ge H, Zhang N, He YX, Zhou J. Functional and structural diversification of incomplete phosphotransferase system in cellulose-degrading clostridia. THE ISME JOURNAL 2023; 17:823-835. [PMID: 36899058 PMCID: PMC10203250 DOI: 10.1038/s41396-023-01392-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 05/24/2023]
Abstract
Carbohydrate utilization is critical to microbial survival. The phosphotransferase system (PTS) is a well-documented microbial system with a prominent role in carbohydrate metabolism, which can transport carbohydrates through forming a phosphorylation cascade and regulate metabolism by protein phosphorylation or interactions in model strains. However, those PTS-mediated regulated mechanisms have been underexplored in non-model prokaryotes. Here, we performed massive genome mining for PTS components in nearly 15,000 prokaryotic genomes from 4,293 species and revealed a high prevalence of incomplete PTSs in prokaryotes with no association to microbial phylogeny. Among these incomplete PTS carriers, a group of lignocellulose degrading clostridia was identified to have lost PTS sugar transporters and carry a substitution of the conserved histidine residue in the core PTS component, HPr (histidine-phosphorylatable phosphocarrier). Ruminiclostridium cellulolyticum was then selected as a representative to interrogate the function of incomplete PTS components in carbohydrate metabolism. Inactivation of the HPr homolog reduced rather than increased carbohydrate utilization as previously indicated. In addition to regulating distinct transcriptional profiles, PTS associated CcpA (Catabolite Control Protein A) homologs diverged from previously described CcpA with varied metabolic relevance and distinct DNA binding motifs. Furthermore, the DNA binding of CcpA homologs is independent of HPr homolog, which is determined by structural changes at the interface of CcpA homologs, rather than in HPr homolog. These data concordantly support functional and structural diversification of PTS components in metabolic regulation and bring novel understanding of regulatory mechanisms of incomplete PTSs in cellulose-degrading clostridia.
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Affiliation(s)
- Tao Xu
- Section on Pathophysiology and Molecular Pharmacology, Joslin Diabetes Center, Boston, MA, USA
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA, USA
- Institute for Environmental Genomics, and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Xuanyu Tao
- Institute for Environmental Genomics, and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Hongxi He
- School of Life Sciences, Anhui University, Hefei, 230601, PR China
- Institutes of Material Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Megan L Kempher
- Institute for Environmental Genomics, and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Siping Zhang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, PR China
| | - Xiaochun Liu
- School of Life Sciences, Anhui University, Hefei, 230601, PR China
- Institutes of Material Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Jun Wang
- School of Life Sciences, Anhui University, Hefei, 230601, PR China
- Institutes of Material Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Dongyu Wang
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Daliang Ning
- Institute for Environmental Genomics, and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
| | - Chongle Pan
- Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA
- School of computer science, University of Oklahoma, Norman, OK, USA
| | - Honghua Ge
- School of Life Sciences, Anhui University, Hefei, 230601, PR China
- Institutes of Material Science and Information Technology, Anhui University, Hefei, 230601, PR China
| | - Nannan Zhang
- School of Life Sciences, Anhui University, Hefei, 230601, PR China.
- Institutes of Material Science and Information Technology, Anhui University, Hefei, 230601, PR China.
| | - Yong-Xing He
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou, 730000, PR China.
| | - Jizhong Zhou
- Institute for Environmental Genomics, and Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA.
- School of Civil Engineering and Environmental Sciences, University of Oklahoma, Norman, OK, USA.
- Earth and Environmental Sciences, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
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11
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Gebhard LJ, Duggin IG, Erdmann S. Improving the genetic system for Halorubrum lacusprofundi to allow in-frame deletions. Front Microbiol 2023; 14:1095621. [PMID: 37065119 PMCID: PMC10102395 DOI: 10.3389/fmicb.2023.1095621] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 03/13/2023] [Indexed: 04/03/2023] Open
Abstract
Halorubrum lacusprofundi is a cold-adapted halophilic archaeon isolated from Deep Lake, Antarctica. Hrr. lacusprofundi is commonly used to study adaptation to cold environments and thereby a potential source for biotechnological products. Additionally, in contrast to other haloarchaeal model organisms, Hrr. lacusprofundi is also susceptible to a range of different viruses and virus-like elements, making it a great model to study virus-host interactions in a cold-adapted organism. A genetic system has previously been reported for Hrr. lacusprofundi; however, it does not allow in-frame deletions and multiple gene knockouts. Here, we report the successful generation of uracil auxotrophic (pyrE2) mutants of two strains of Hrr. lacusprofundi. Subsequently, we attempted to generate knockout mutants using the auxotrophic marker for selection. However, surprisingly, only the combination of the auxotrophic marker and antibiotic selection allowed the timely and clean in-frame deletion of a target gene. Finally, we show that vectors established for the model organism Haloferax volcanii are deployable for genetic manipulation of Hrr. lacusprofundi, allowing the use of the portfolio of genetic tools available for H. volcanii in Hrr. lacusprofundi.
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Affiliation(s)
- L. Johanna Gebhard
- Archaeal Virology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Iain G. Duggin
- The Australian Institute for Microbiology and Infection, University of Technology Sydney, Sydney, NSW, Australia
| | - Susanne Erdmann
- Archaeal Virology, Max Planck Institute for Marine Microbiology, Bremen, Germany
- *Correspondence: Susanne Erdmann,
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12
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The Hypersaline Archaeal Histones HpyA and HstA Are DNA Binding Proteins That Defy Categorization According to Commonly Used Functional Criteria. mBio 2023; 14:e0344922. [PMID: 36779711 PMCID: PMC10128011 DOI: 10.1128/mbio.03449-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
Histone proteins are found across diverse lineages of Archaea, many of which package DNA and form chromatin. However, previous research has led to the hypothesis that the histone-like proteins of high-salt-adapted archaea, or halophiles, function differently. The sole histone protein encoded by the model halophilic species Halobacterium salinarum, HpyA, is nonessential and expressed at levels too low to enable genome-wide DNA packaging. Instead, HpyA mediates the transcriptional response to salt stress. Here we compare the features of genome-wide binding of HpyA to those of HstA, the sole histone of another model halophile, Haloferax volcanii. hstA, like hpyA, is a nonessential gene. To better understand HpyA and HstA functions, protein-DNA binding data (chromatin immunoprecipitation sequencing [ChIP-seq]) of these halophilic histones are compared to publicly available ChIP-seq data from DNA binding proteins across all domains of life, including transcription factors (TFs), nucleoid-associated proteins (NAPs), and histones. These analyses demonstrate that HpyA and HstA bind the genome infrequently in discrete regions, which is similar to TFs but unlike NAPs, which bind a much larger genomic fraction. However, unlike TFs that typically bind in intergenic regions, HpyA and HstA binding sites are located in both coding and intergenic regions. The genome-wide dinucleotide periodicity known to facilitate histone binding was undetectable in the genomes of both species. Instead, TF-like and histone-like binding sequence preferences were detected for HstA and HpyA, respectively. Taken together, these data suggest that halophilic archaeal histones are unlikely to facilitate genome-wide chromatin formation and that their function defies categorization as a TF, NAP, or histone. IMPORTANCE Most cells in eukaryotic species-from yeast to humans-possess histone proteins that pack and unpack DNA in response to environmental cues. These essential proteins regulate genes necessary for important cellular processes, including development and stress protection. Although the histone fold domain originated in the domain of life Archaea, the function of archaeal histone-like proteins is not well understood relative to those of eukaryotes. We recently discovered that, unlike histones of eukaryotes, histones in hypersaline-adapted archaeal species do not package DNA and can act as transcription factors (TFs) to regulate stress response gene expression. However, the function of histones across species of hypersaline-adapted archaea still remains unclear. Here, we compare hypersaline histone function to a variety of DNA binding proteins across the tree of life, revealing histone-like behavior in some respects and specific transcriptional regulatory function in others.
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13
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Characterization of L-arabinose/D-galactose 1-dehydrogenase from Thermotoga maritima and its application in galactonate production. World J Microbiol Biotechnol 2022; 38:223. [DOI: 10.1007/s11274-022-03406-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 08/29/2022] [Indexed: 11/26/2022]
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14
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Mukherji S, Bakshi U, Ghosh A. Draft genome sequences of hydrocarbon degrading Haloferax sp. AB510, Haladaptatus sp. AB618 and Haladaptatus sp. AB643 isolated from the estuarine sediments of Sundarban mangrove forests, India. 3 Biotech 2022; 12:204. [PMID: 35935548 PMCID: PMC9349328 DOI: 10.1007/s13205-022-03273-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 07/20/2022] [Indexed: 11/25/2022] Open
Abstract
The present study reports the draft genomes of three hydrocarbon-degrading haloarchaeal strains Haloferax sp. AB510, Haladaptatus sp. AB618 and Haladaptatus sp. AB643 that were isolated from the estuarine sediments of Sundarban mangrove forests, India. All three genomes had a high GC content of around 60%, characteristic of the haloarchaea. The Haloferax sp. AB510 genome was around 3.9 Mb in size and consisted of 4567 coding sequences and 54 RNAs. The Haladaptatus sp. AB618 and Haladaptatus sp. AB643 genomes were comparatively larger and around 4.8 Mb each. The AB618 and AB643 genomes comprised 5279 and 5304 coding sequences and 60 and 59 RNAs, respectively. All three of the genomes encoded several genes that attributed to their survival in the presence of hydrocarbons in their native habitats. Functional annotation and curation of the sequenced genomes suggested that the Haloferax sp. AB510 strain utilized the gentisate pathway of aromatic compound degradation. While the Haladaptatus sp. AB618 and Haladaptatus sp. AB643 strains possessed the freedom of utilizing both the gentisate and the catechol pathways for degrading aromatic hydrocarbons. Supplementary Information The online version contains supplementary material available at 10.1007/s13205-022-03273-5.
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Affiliation(s)
- Shayantan Mukherji
- Department of Biochemistry, Bose Institute, EN 80, Sector V, Bidhan Nagar, Kolkata, West Bengal 700091 India
| | - Utpal Bakshi
- Institute of Health Sciences, Presidency University, 86/1 College Street, Kolkata, West Bengal 700073 India
| | - Abhrajyoti Ghosh
- Department of Biochemistry, Bose Institute, EN 80, Sector V, Bidhan Nagar, Kolkata, West Bengal 700091 India
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15
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Isolation of a virus causing a chronic infection in the archaeal model organism Haloferax volcanii reveals antiviral activities of a provirus. Proc Natl Acad Sci U S A 2022; 119:e2205037119. [PMID: 35994644 PMCID: PMC9436352 DOI: 10.1073/pnas.2205037119] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Viruses are important ecological, biogeochemical, and evolutionary drivers in every environment. Upon infection, they often cause the lysis of the host cell. However, some viruses exhibit alternative life cycles, such as chronic infections without cell lysis. The nature and the impact of chronic infections in prokaryotic host organisms remains largely unknown. Here, we characterize a novel haloarchaeal virus, Haloferax volcanii pleomorphic virus 1 (HFPV-1), which is currently the only virus infecting the model haloarchaeon Haloferax volcanii DS2, and demonstrate that HFPV-1 and H. volcanii are a great model system to study virus-host interactions in archaea. HFPV-1 is a pleomorphic virus that causes a chronic infection with continuous release of virus particles, but host and virus coexist without cell lysis or the appearance of resistant cells. Despite an only minor impact of the infection on host growth, we uncovered an extensive remodeling of the transcriptional program of the host (up to 1,049 differentially expressed genes). These changes are highlighted by a down-regulation of two endogenous provirus regions in the host genome, and we show that HFPV-1 infection is strongly influenced by a cross-talk between HFPV-1 and one of the proviruses mediated by a superinfection-like exclusion mechanism. Furthermore, HFPV-1 has a surprisingly wide host range among haloarchaea, and purified virus DNA can cause an infection after transformation into the host, making HFPV-1 a candidate for being developed into a genetic tool for a range of so far inaccessible haloarchaea.
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16
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Robinson A, Ulrich SM. Haloferax volcanii Remains Viable and Shows Morphological Changes under Anoxic (CO 2-Enriched) and Hypobaric (2.4 kPa) Atmospheric Conditions. ASTROBIOLOGY 2022; 22:829-837. [PMID: 35325555 DOI: 10.1089/ast.2021.0076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Potentially habitable zones have been discovered on Mars today in underground areas containing perchlorate brines. Understanding the low-pressure adaptations of microorganisms is essential in learning more about what life could potentially be found on Mars today or could have existed in the distant past. Many studies have looked at low-pressure adaptations in bacteria; however, studies aimed at understanding these adaptations in archaea are scarcer. Haloferax volcanii is a species of halophilic archaea documented to tolerate high concentrations of oxidizing agents present on Mars (i.e., perchlorates and nitrates). In this study, we expose H. volcanii to a hypobaric (2.4 kPa) and an anoxic CO2-enriched atmosphere in the presence of perchlorate, chlorate, and nitrate. While no growth was observed during incubation in these conditions, survivability was increased in cultures incubated in low-pressure atmospheric conditions compared to ambient Earth atmospheric pressures. Scanning electron microscopy observations showed morphological changes in low-pressure conditions not observed at ambient Earth atmospheric pressures. Results suggest that previously undocumented low-pressure adaptations in H. volcanii increase survivability in simulated subsurface martian conditions. Future experiments to understand the changes in gene expression under these conditions may be valuable to understand more about low-pressure adaptations in archaea.
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Affiliation(s)
- Adam Robinson
- Department of Natural Science, St. Petersburg College, Clearwater, Florida, USA
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17
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The Viral Susceptibility of the Haloferax Species. Viruses 2022; 14:v14061344. [PMID: 35746816 PMCID: PMC9229481 DOI: 10.3390/v14061344] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/15/2022] [Accepted: 06/17/2022] [Indexed: 11/17/2022] Open
Abstract
Viruses can infect members of all three domains of life. However, little is known about viruses infecting archaea and the mechanisms that determine their host interactions are poorly understood. Investigations of molecular mechanisms of viral infection rely on genetically accessible virus–host model systems. Euryarchaea belonging to the genus Haloferax are interesting models, as a reliable genetic system and versatile microscopy methods are available. However, only one virus infecting the Haloferax species is currently available. In this study, we tested ~100 haloarchaeal virus isolates for their infectivity on 14 Haloferax strains. From this, we identified 10 virus isolates in total capable of infecting Haloferax strains, which represented myovirus or siphovirus morphotypes. Surprisingly, the only susceptible strain of all 14 tested was Haloferax gibbonsii LR2-5, which serves as an auspicious host for all of these 10 viruses. By applying comparative genomics, we shed light on factors determining the host range of haloarchaeal viruses on Haloferax. We anticipate our study to be a starting point in the study of haloarchaeal virus–host interactions.
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18
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Koper K, Han SW, Pastor DC, Yoshikuni Y, Maeda HA. Evolutionary Origin and Functional Diversification of Aminotransferases. J Biol Chem 2022; 298:102122. [PMID: 35697072 PMCID: PMC9309667 DOI: 10.1016/j.jbc.2022.102122] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 06/06/2022] [Accepted: 06/07/2022] [Indexed: 11/30/2022] Open
Abstract
Aminotransferases (ATs) are pyridoxal 5′-phosphate–dependent enzymes that catalyze the transamination reactions between amino acid donor and keto acid acceptor substrates. Modern AT enzymes constitute ∼2% of all classified enzymatic activities, play central roles in nitrogen metabolism, and generate multitude of primary and secondary metabolites. ATs likely diverged into four distinct AT classes before the appearance of the last universal common ancestor and further expanded to a large and diverse enzyme family. Although the AT family underwent an extensive functional specialization, many AT enzymes retained considerable substrate promiscuity and multifunctionality because of their inherent mechanistic, structural, and functional constraints. This review summarizes the evolutionary history, diverse metabolic roles, reaction mechanisms, and structure–function relationships of the AT family enzymes, with a special emphasis on their substrate promiscuity and multifunctionality. Comprehensive characterization of AT substrate specificity is still needed to reveal their true metabolic functions in interconnecting various branches of the nitrogen metabolic network in different organisms.
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Affiliation(s)
- Kaan Koper
- Department of Botany, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Sang-Woo Han
- The US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | | | - Yasuo Yoshikuni
- The US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Global Center for Food, Land, and Water Resources, Research Faculty of Agriculture, Hokkaido University, Hokkaido 060-8589, Japan
| | - Hiroshi A Maeda
- Department of Botany, University of Wisconsin-Madison, Madison, WI, 53706, USA
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19
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Zhang H, Gong X, Zhao Q, Mukai T, Vargas-Rodriguez O, Zhang H, Zhang Y, Wassel P, Amikura K, Maupin-Furlow J, Ren Y, Xu X, Wolf YI, Makarova K, Koonin E, Shen Y, Söll D, Fu X. The tRNA discriminator base defines the mutual orthogonality of two distinct pyrrolysyl-tRNA synthetase/tRNAPyl pairs in the same organism. Nucleic Acids Res 2022; 50:4601-4615. [PMID: 35466371 PMCID: PMC9071458 DOI: 10.1093/nar/gkac271] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/01/2022] [Accepted: 04/07/2022] [Indexed: 12/24/2022] Open
Abstract
Site-specific incorporation of distinct non-canonical amino acids into proteins via genetic code expansion requires mutually orthogonal aminoacyl-tRNA synthetase/tRNA pairs. Pyrrolysyl-tRNA synthetase (PylRS)/tRNAPyl pairs are ideal for genetic code expansion and have been extensively engineered for developing mutually orthogonal pairs. Here, we identify two novel wild-type PylRS/tRNAPyl pairs simultaneously present in the deep-rooted extremely halophilic euryarchaeal methanogen Candidatus Methanohalarchaeum thermophilum HMET1, and show that both pairs are functional in the model halophilic archaeon Haloferax volcanii. These pairs consist of two different PylRS enzymes and two distinct tRNAs with dissimilar discriminator bases. Surprisingly, these two PylRS/tRNAPyl pairs display mutual orthogonality enabled by two unique features, the A73 discriminator base of tRNAPyl2 and a shorter motif 2 loop in PylRS2. In vivo translation experiments show that tRNAPyl2 charging by PylRS2 is defined by the enzyme's shortened motif 2 loop. Finally, we demonstrate that the two HMET1 PylRS/tRNAPyl pairs can simultaneously decode UAG and UAA codons for incorporation of two distinct noncanonical amino acids into protein. This example of a single base change in a tRNA leading to additional coding capacity suggests that the growth of the genetic code is not yet limited by the number of identity elements fitting into the tRNA structure.
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Affiliation(s)
| | | | | | - Takahito Mukai
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Oscar Vargas-Rodriguez
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Huiming Zhang
- BGI-Shenzhen, Shenzhen, 518083, China,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yuxing Zhang
- BGI-Shenzhen, Shenzhen, 518083, China,Sino-Danish College, University of the Chinese Academy of Sciences, Beijing, China
| | - Paul Wassel
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
| | - Kazuaki Amikura
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Julie Maupin-Furlow
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA,Genetics Institute, University of Florida, Gainesville, FL 32611, USA
| | - Yan Ren
- BGI-Shenzhen, Shenzhen, 518083, China
| | - Xun Xu
- BGI-Shenzhen, Shenzhen, 518083, China
| | - Yuri I Wolf
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Kira S Makarova
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - Yue Shen
- Correspondence may also be addressed to Yue Shen.
| | - Dieter Söll
- To whom correspondence should be addressed. Tel: +1 203 4326200;
| | - Xian Fu
- Correspondence may also be addressed to Xian Fu.
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20
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Ithurbide S, Gribaldo S, Albers SV, Pende N. Spotlight on FtsZ-based cell division in Archaea. Trends Microbiol 2022; 30:665-678. [PMID: 35246355 DOI: 10.1016/j.tim.2022.01.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 12/22/2021] [Accepted: 01/10/2022] [Indexed: 12/15/2022]
Abstract
Compared with the extensive knowledge on cell division in model eukaryotes and bacteria, little is known about how archaea divide. Interestingly, both endosomal sorting complex required for transport (ESCRT)-based and FtsZ-based cell division systems are found in members of the Archaea. In the past couple of years, several studies have started to shed light on FtsZ-based cell division processes in members of the Euryarchaeota. In this review we highlight recent findings in this emerging field of research. We present current knowledge of the cell division machinery of halophiles which relies on two FtsZ proteins, and we compare it with that of methanobacteria, which relies on only one FtsZ. Finally, we discuss how these differences relate to the distinct cell envelopes of these two archaeal model systems.
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Affiliation(s)
- Solenne Ithurbide
- Molecular Biology of Archaea, Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Simonetta Gribaldo
- Evolutionary Biology of the Microbial Cell Unit, CNRS UMR2001, Department of Microbiology, Institut Pasteur, Paris, France.
| | - Sonja-Verena Albers
- Molecular Biology of Archaea, Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany.
| | - Nika Pende
- Evolutionary Biology of the Microbial Cell Unit, CNRS UMR2001, Department of Microbiology, Institut Pasteur, Paris, France
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21
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Quantitative Mass Spectrometry by SILAC in Haloferax volcanii. Methods Mol Biol 2022; 2522:255-266. [PMID: 36125755 PMCID: PMC9926160 DOI: 10.1007/978-1-0716-2445-6_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The development of mass spectrometry (MS)-based proteomics methods has been critical in providing new insight about cellular processes and adaptations in all domains of life. While traditional MS-based methods are not inherently quantitative, technologies are now available to overcome this limitation. Of note, stable isotope labeling of amino acids in cell culture (SILAC) is reported as a reliable tool to label proteomes for quantitative MS-based proteomics that is accurate and flexible for multiplexing. The isotopically labeled lysine and arginine are easily incorporated into the proteome of cells auxotrophic for these amino acids. Microorganisms of the domain Archaea provide a fascinating alternative to understanding cellular adaptations and responses to environmental stresses. However, the availability of preferred SILAC-based quantitative analyses is limited. This protocol describes the use of SILAC to quantitatively analyze the proteome of Haloferax volcanii, a mesophilic halophilic archaeon that is easy to grow and requires no special equipment to maintain.
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22
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Schramm F, Borst A, Linne U, Soppa J. Elucidation of the Translation Initiation Factor Interaction Network of Haloferax volcanii Reveals Coupling of Transcription and Translation in Haloarchaea. Front Microbiol 2021; 12:742806. [PMID: 34764944 PMCID: PMC8576121 DOI: 10.3389/fmicb.2021.742806] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/29/2021] [Indexed: 02/04/2023] Open
Abstract
Translation is an important step in gene expression. Initiation of translation is rate-limiting, and it is phylogenetically more diverse than elongation or termination. Bacteria contain only three initiation factors. In stark contrast, eukaryotes contain more than 10 (subunits of) initiation factors (eIFs). The genomes of archaea contain many genes that are annotated to encode archaeal homologs of eukaryotic initiation factors (aIFs). However, experimental characterization of aIFs is scarce and mostly restricted to very few species. To broaden the view, the protein-protein interaction network of aIFs in the halophilic archaeon Haloferax volcanii has been characterized. To this end, tagged versions of 14 aIFs were overproduced, affinity isolated, and the co-isolated binding partners were identified by peptide mass fingerprinting and MS/MS analyses. The aIF-aIF interaction network was resolved, and it was found to contain two interaction hubs, (1) the universally conserved factor aIF5B, and (2) a protein that has been annotated as the enzyme ribose-1,5-bisphosphate isomerase, which we propose to rename to aIF2Bα. Affinity isolation of aIFs also led to the co-isolation of many ribosomal proteins, but also transcription factors and subunits of the RNA polymerase (Rpo). To analyze a possible coupling of transcription and translation, seven tagged Rpo subunits were overproduced, affinity isolated, and co-isolated proteins were identified. The Rpo interaction network contained many transcription factors, but also many ribosomal proteins as well as the initiation factors aIF5B and aIF2Bα. These results showed that transcription and translation are coupled in haloarchaea, like in Escherichia coli. It seems that aIF5B and aIF2Bα are not only interaction hubs in the translation initiation network, but also key players in the transcription-translation coupling.
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Affiliation(s)
- Franziska Schramm
- Institute for Molecular Biosciences, Biocentre, Goethe-University, Frankfurt, Germany
| | - Andreas Borst
- Institute for Molecular Biosciences, Biocentre, Goethe-University, Frankfurt, Germany
| | - Uwe Linne
- Mass Spectrometry Facility, Department of Chemistry, Phillipps University Marburg, Marburg, Germany
| | - Jörg Soppa
- Institute for Molecular Biosciences, Biocentre, Goethe-University, Frankfurt, Germany
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23
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Perez MF, Saona LA, Farías ME, Poehlein A, Meinhardt F, Daniel R, Dib JR. Assessment of the plasmidome of an extremophilic microbial community from the Diamante Lake, Argentina. Sci Rep 2021; 11:21459. [PMID: 34728656 PMCID: PMC8563766 DOI: 10.1038/s41598-021-00753-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 10/15/2021] [Indexed: 12/02/2022] Open
Abstract
Diamante Lake located at 4589 m.a.s.l. in the Andean Puna constitutes an extreme environment. It is exposed to multiple extreme conditions such as an unusually high concentration of arsenic (over 300 mg L-1) and low oxygen pressure. Microorganisms thriving in the lake display specific genotypes that facilitate survival, which include at least a multitude of plasmid-encoded resistance traits. Hence, the genetic information provided by the plasmids essentially contributes to understand adaptation to different stressors. Though plasmids from cultivable organisms have already been analyzed to the sequence level, the impact of the entire plasmid-borne genetic information on such microbial ecosystem is not known. This study aims at assessing the plasmidome from Diamante Lake, which facilitates the identification of potential hosts and prediction of gene functions as well as the ecological impact of mobile genetic elements. The deep-sequencing analysis revealed a large fraction of previously unknown DNA sequences of which the majority encoded putative proteins of unknown function. Remarkably, functions related to the oxidative stress response, DNA repair, as well as arsenic- and antibiotic resistances were annotated. Additionally, all necessary capacities related to plasmid replication, mobilization and maintenance were detected. Sequences characteristic for megaplasmids and other already known plasmid-associated genes were identified as well. The study highlights the potential of the deep-sequencing approach specifically targeting plasmid populations as it allows to evaluate the ecological impact of plasmids from (cultivable and non-cultivable) microorganisms, thereby contributing to the understanding of the distribution of resistance factors within an extremophilic microbial community.
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Affiliation(s)
- María Florencia Perez
- grid.423606.50000 0001 1945 2152Planta Piloto de Procesos Industriales Microbiológicos, Consejo Nacional de Investigaciones Científicas y Técnicas, San Miguel de Tucumán, Tucumán Argentina
| | - Luis Alberto Saona
- grid.423606.50000 0001 1945 2152Planta Piloto de Procesos Industriales Microbiológicos, Consejo Nacional de Investigaciones Científicas y Técnicas, San Miguel de Tucumán, Tucumán Argentina
| | - María Eugenia Farías
- grid.423606.50000 0001 1945 2152Planta Piloto de Procesos Industriales Microbiológicos, Consejo Nacional de Investigaciones Científicas y Técnicas, San Miguel de Tucumán, Tucumán Argentina
| | - Anja Poehlein
- grid.7450.60000 0001 2364 4210Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August University of Göttingen, Grisebachstr. 8, 37077 Göttingen, Germany
| | - Friedhelm Meinhardt
- grid.5949.10000 0001 2172 9288Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms Universität Münster, Münster, Germany
| | - Rolf Daniel
- grid.7450.60000 0001 2364 4210Genomic and Applied Microbiology and Göttingen Genomics Laboratory, Institute of Microbiology and Genetics, Georg-August University of Göttingen, Grisebachstr. 8, 37077 Göttingen, Germany
| | - Julián Rafael Dib
- grid.423606.50000 0001 1945 2152Planta Piloto de Procesos Industriales Microbiológicos, Consejo Nacional de Investigaciones Científicas y Técnicas, San Miguel de Tucumán, Tucumán Argentina ,grid.108162.c0000000121496664Instituto de Microbiología, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Miguel de Tucumán, Tucumán Argentina
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Ubiquitousness of Haloferax and Carotenoid Producing Genes in Arabian Sea Coastal Biosystems of India. Mar Drugs 2021; 19:md19080442. [PMID: 34436281 PMCID: PMC8400781 DOI: 10.3390/md19080442] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/26/2021] [Accepted: 07/28/2021] [Indexed: 12/14/2022] Open
Abstract
This study presents a comparative analysis of halophiles from the global open sea and coastal biosystems through shotgun metagenomes (n = 209) retrieved from public repositories. The open sea was significantly enriched with Prochlorococcus and Candidatus pelagibacter. Meanwhile, coastal biosystems were dominated by Marinobacter and Alcanivorax. Halophilic archaea Haloarcula and Haloquandratum, predominant in the coastal biosystem, were significantly (p < 0.05) enriched in coastal biosystems compared to the open sea. Analysis of whole genomes (n = 23,540), retrieved from EzBioCloud, detected crtI in 64.66% of genomes, while cruF was observed in 1.69% Bacteria and 40.75% Archaea. We further confirmed the viability and carotenoid pigment production by pure culture isolation (n = 1351) of extreme halophiles from sediments (n = 410 × 3) sampling at the Arabian coastline of India. All red-pigmented isolates were represented exclusively by Haloferax, resistant to saturated NaCl (6 M), and had >60% G + C content. Multidrug resistance to tetracycline, gentamicin, ampicillin, and chloramphenicol were also observed. Our study showed that coastal biosystems could be more suited for bioprospection of halophiles rather than the open sea.
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Kasirajan L, Adams Z, Couto-Rodriguez RL, Gal D, Jia H, Mondragon P, Wassel PC, Yu D, Uthandi S, Maupin-Furlow JA. High-level synthesis and secretion of laccase, a metalloenzyme biocatalyst, by the halophilic archaeon Haloferax volcanii. Methods Enzymol 2021; 659:297-313. [PMID: 34752290 DOI: 10.1016/bs.mie.2021.05.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Haloarchaea and their enzymes have extremophilic properties desirable for use as platform organisms and biocatalysts in the bioindustry. These GRAS (generally regarded as safe) designated microbes thrive in hypersaline environments and use a salt-in strategy to maintain osmotic homeostasis. This unusual strategy has resulted in the evolution of most of the intracellular and extracellular enzymes of haloarchaea to be active and stable not only in high salt (2-5M) but also in low salt (0.2M). This salt tolerance is correlated with a resilience to low water activity, thus, rendering the haloarchaeal enzymes active and stable in organic solvent and temperatures of 50-60°C used in the enzymatic biodelignification and saccharification of lignocellulosic materials. High-level secretion of haloarchaeal enzymes to the extracellular milieu is useful for many applications, including enzymes that deconstruct biomass to allow for lignin depolymerization and simultaneous fermentation of sugars released from hemicellulose and cellulose fractions of lignocellulosics. Here we detail strategies and methods useful for high-level secretion of a laccase, HvLccA, that mediates oxidation of various phenolics by engineering a recombinant strain of the haloarchaeon Haloferax volcanii.
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Affiliation(s)
- Lakshmi Kasirajan
- Division of Crop Improvement, ICAR Sugarcane Breeding Institute, Coimbatore, India; Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States
| | - Zachary Adams
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States
| | - Ricardo L Couto-Rodriguez
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States
| | - Daniel Gal
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States
| | - Huiyong Jia
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States
| | - Paula Mondragon
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States
| | - Paul C Wassel
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States; Genetics Institute, University of Florida, Gainesville, FL, United States
| | - David Yu
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States; Genetics Institute, University of Florida, Gainesville, FL, United States
| | - Sivakumar Uthandi
- Biocatalysts Laboratory, Department of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India
| | - Julie A Maupin-Furlow
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL, United States; Genetics Institute, University of Florida, Gainesville, FL, United States.
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Li J, Gao Y, Dong H, Sheng GP. Haloarchaea, excellent candidates for removing pollutants from hypersaline wastewater. Trends Biotechnol 2021; 40:226-239. [PMID: 34284891 DOI: 10.1016/j.tibtech.2021.06.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/23/2021] [Accepted: 06/23/2021] [Indexed: 11/25/2022]
Abstract
Hypersaline wastewater is difficult to treat due to the inhibition of salt stress on microbes' viability and metabolic capabilities. Haloarchaea, native microorganisms that thrive in hypersaline habitats, overcome this key obstacle naturally. This review provides a comprehensive overview of the metabolic versatility of Haloarchaea in hypersaline wastewater treatment, including carbon, nitrogen, phosphorus, sulfur, and heavy metal metabolism. It also analyzes factors affecting pollutant removal and addresses metabolic mechanisms. Additionally, haloarchaea microbial characteristics and strategies to cope with salt stress are highlighted. Finally, the biotechnological potential of biomolecules produced from haloarchaea is investigated. To get better insight into the potential of haloarchaea, a deeper investigation of basic metabolism and more in-depth studies of their genomics and applications in actual wastewater are also necessary.
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Affiliation(s)
- Jin Li
- School of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China.
| | - Yuanyuan Gao
- School of Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Huiyu Dong
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-environmental Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Guo-Ping Sheng
- Chinese Academy of Sciences Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China.
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Ibrahim AGAER, Vêncio RZN, Lorenzetti APR, Koide T. Halobacterium salinarum and Haloferax volcanii Comparative Transcriptomics Reveals Conserved Transcriptional Processing Sites. Genes (Basel) 2021; 12:genes12071018. [PMID: 34209065 PMCID: PMC8303175 DOI: 10.3390/genes12071018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/25/2021] [Accepted: 05/27/2021] [Indexed: 01/15/2023] Open
Abstract
Post-transcriptional processing of messenger RNA is an important regulatory strategy that allows relatively fast responses to changes in environmental conditions. In halophile systems biology, the protein perspective of this problem (i.e., ribonucleases which implement the cleavages) is generally more studied than the RNA perspective (i.e., processing sites). In the present in silico work, we mapped genome-wide transcriptional processing sites (TPS) in two halophilic model organisms, Halobacterium salinarum NRC-1 and Haloferax volcanii DS2. TPS were established by reanalysis of publicly available differential RNA-seq (dRNA-seq) data, searching for non-primary (monophosphorylated RNAs) enrichment. We found 2093 TPS in 43% of H. salinarum genes and 3515 TPS in 49% of H. volcanii chromosomal genes. Of the 244 conserved TPS sites found, the majority were located around start and stop codons of orthologous genes. Specific genes are highlighted when discussing antisense, ribosome and insertion sequence associated TPS. Examples include the cell division gene ftsZ2, whose differential processing signal along growth was detected and correlated with post-transcriptional regulation, and biogenesis of sense overlapping transcripts associated with IS200/IS605. We hereby present the comparative, transcriptomics-based processing site maps with a companion browsing interface.
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Affiliation(s)
- Amr Galal Abd El-Raheem Ibrahim
- Department of Computation and Mathematics, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-900, Brazil; (A.G.A.E.-R.I.); (R.Z.N.V.)
| | - Ricardo Z. N. Vêncio
- Department of Computation and Mathematics, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto 14040-900, Brazil; (A.G.A.E.-R.I.); (R.Z.N.V.)
| | - Alan P. R. Lorenzetti
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, Universidade de São Paulo, Ribeirão Preto 14040-900, Brazil;
| | - Tie Koide
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, Universidade de São Paulo, Ribeirão Preto 14040-900, Brazil;
- Correspondence: ; Tel.: +55-16-3315-3107
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Open Issues for Protein Function Assignment in Haloferax volcanii and Other Halophilic Archaea. Genes (Basel) 2021; 12:genes12070963. [PMID: 34202810 PMCID: PMC8305020 DOI: 10.3390/genes12070963] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/10/2021] [Accepted: 06/15/2021] [Indexed: 12/14/2022] Open
Abstract
Background: Annotation ambiguities and annotation errors are a general challenge in genomics. While a reliable protein function assignment can be obtained by experimental characterization, this is expensive and time-consuming, and the number of such Gold Standard Proteins (GSP) with experimental support remains very low compared to proteins annotated by sequence homology, usually through automated pipelines. Even a GSP may give a misleading assignment when used as a reference: the homolog may be close enough to support isofunctionality, but the substrate of the GSP is absent from the species being annotated. In such cases, the enzymes cannot be isofunctional. Here, we examined a variety of such issues in halophilic archaea (class Halobacteria), with a strong focus on the model haloarchaeon Haloferax volcanii. Results: Annotated proteins of Hfx. volcanii were identified for which public databases tend to assign a function that is probably incorrect. In some cases, an alternative, probably correct, function can be predicted or inferred from the available evidence, but this has not been adopted by public databases because experimental validation is lacking. In other cases, a probably invalid specific function is predicted by homology, and while there is evidence that this assigned function is unlikely, the true function remains elusive. We listed 50 of those cases, each with detailed background information, so that a conclusion about the most likely biological function can be drawn. For reasons of brevity and comprehension, only the key aspects are listed in the main text, with detailed information being provided in a corresponding section of the Supplementary Materials. Conclusions: Compiling, describing and summarizing these open annotation issues and functional predictions will benefit the scientific community in the general effort to improve the evaluation of protein function assignments and more thoroughly detail them. By highlighting the gaps and likely annotation errors currently in the databases, we hope this study will provide a framework for experimentalists to systematically confirm (or disprove) our function predictions or to uncover yet more unexpected functions.
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Cell division in the archaeon Haloferax volcanii relies on two FtsZ proteins with distinct functions in division ring assembly and constriction. Nat Microbiol 2021; 6:594-605. [PMID: 33903747 PMCID: PMC7611241 DOI: 10.1038/s41564-021-00894-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 03/22/2021] [Indexed: 02/02/2023]
Abstract
In bacteria, the tubulin homologue FtsZ assembles a cytokinetic ring, termed the Z ring, and plays a key role in the machinery that constricts to divide the cells. Many archaea encode two FtsZ proteins from distinct families, FtsZ1 and FtsZ2, with previously unclear functions. Here, we show that Haloferax volcanii cannot divide properly without either or both FtsZ proteins, but DNA replication continues and cells proliferate in alternative ways, such as blebbing and fragmentation, via remarkable envelope plasticity. FtsZ1 and FtsZ2 colocalize to form the dynamic division ring. However, FtsZ1 can assemble rings independent of FtsZ2, and stabilizes FtsZ2 in the ring, whereas FtsZ2 functions primarily in the constriction mechanism. FtsZ1 also influenced cell shape, suggesting it forms a hub-like platform at midcell for the assembly of shape-related systems too. Both FtsZ1 and FtsZ2 are widespread in archaea with a single S-layer envelope, but archaea with a pseudomurein wall and division septum only have FtsZ1. FtsZ1 is therefore likely to provide a fundamental recruitment role in diverse archaea, and FtsZ2 is required for constriction of a flexible S-layer envelope, where an internal constriction force might dominate the division mechanism, in contrast with the single-FtsZ bacteria and archaea that divide primarily by wall ingrowth.
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30
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Nitrate-responsive suppression of DMSO respiration in a facultative anaerobic haloarchaeon Haloferax volcanii. J Bacteriol 2021; 203:e0065520. [PMID: 33820797 DOI: 10.1128/jb.00655-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Haloferax volcanii is a facultative anaerobic haloarchaeon that can grow using nitrate or dimethyl sulfoxide (DMSO) as respiratory substrates in an anaerobic condition. Comparative transcriptome analysis of denitrifying and aerobic cells of H. volcanii indicated extensive changes in the gene expression involving activation of denitrification, suppression of DMSO respiration, and conversion of the heme biosynthetic pathway under denitrifying condition. Anaerobic growth of H. volcanii by DMSO respiration was inhibited at nitrate concentrations lower than 1 mM, whereas the nitrate-responsive growth inhibition was not observed in the ΔnarO mutant. A reporter assay experiment demonstrated that transcription of the dms operon was suppressed by nitrate. In contrast, anaerobic growth of the ΔdmsR mutant by denitrification was little affected by addition of DMSO. NarO has been identified as an activator of the denitrification-related genes in response to anaerobic conditions, and here we found that NarO is also involved in nitrate-responsive suppression of the dms operon. Nitrate-responsive suppression of DMSO respiration is known in several bacteria, such as Escherichia coli and photosynthetic Rhodobacter sp. This is the first report to show that a regulatory mechanism that suppresses DMSO respiration in response to nitrate exists not only in bacteria but also in the haloarchaea.IMPORTANCE Haloferax volcanii can grow anaerobically by denitrification (nitrate respiration) or DMSO respiration. In the facultative anaerobic bacteria that can grow by both nitrate respiration and DMSO respiration, nitrate respiration is preferentially induced when both nitrate and DMSO are available as respiratory substrates. The results of transcriptome analysis, growth phenotyping, and reporter assay indicated that DMSO respiration is suppressed in response to nitrate in H. volcanii The haloarchaea-specific regulator NarO, which activates denitrification under anaerobic conditions, is suggested to be involved in the nitrate-responsive suppression of DMSO respiration.
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31
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Harris AJ, Goldman AD. The very early evolution of protein translocation across membranes. PLoS Comput Biol 2021; 17:e1008623. [PMID: 33684113 PMCID: PMC7987157 DOI: 10.1371/journal.pcbi.1008623] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 03/23/2021] [Accepted: 12/10/2020] [Indexed: 11/18/2022] Open
Abstract
In this study, we used a computational approach to investigate the early evolutionary history of a system of proteins that, together, embed and translocate other proteins across cell membranes. Cell membranes comprise the basis for cellularity, which is an ancient, fundamental organizing principle shared by all organisms and a key innovation in the evolution of life on Earth. Two related requirements for cellularity are that organisms are able to both embed proteins into membranes and translocate proteins across membranes. One system that accomplishes these tasks is the signal recognition particle (SRP) system, in which the core protein components are the paralogs, FtsY and Ffh. Complementary to the SRP system is the Sec translocation channel, in which the primary channel-forming protein is SecY. We performed phylogenetic analyses that strongly supported prior inferences that FtsY, Ffh, and SecY were all present by the time of the last universal common ancestor of life, the LUCA, and that the ancestor of FtsY and Ffh existed before the LUCA. Further, we combined ancestral sequence reconstruction and protein structure and function prediction to show that the LUCA had an SRP system and Sec translocation channel that were similar to those of extant organisms. We also show that the ancestor of Ffh and FtsY that predated the LUCA was more similar to FtsY than Ffh but could still have comprised a rudimentary protein translocation system on its own. Duplication of the ancestor of FtsY and Ffh facilitated the specialization of FtsY as a membrane bound receptor and Ffh as a cytoplasmic protein that could bind nascent proteins with specific membrane-targeting signal sequences. Finally, we analyzed amino acid frequencies in our ancestral sequence reconstructions to infer that the ancestral Ffh/FtsY protein likely arose prior to or just after the completion of the canonical genetic code. Taken together, our results offer a window into the very early evolutionary history of cellularity.
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Affiliation(s)
- AJ Harris
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Department of Biology, Oberlin College and Conservatory, K123 Science Center, Oberlin, Ohio, United States of America
| | - Aaron David Goldman
- Department of Biology, Oberlin College and Conservatory, K123 Science Center, Oberlin, Ohio, United States of America
- Blue Marble Space Institute of Science, Seattle, Washington, United States of America
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32
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Tittes C, Schwarzer S, Pfeiffer F, Dyall-Smith M, Rodriguez-Franco M, Oksanen HM, Quax TEF. Cellular and Genomic Properties of Haloferax gibbonsii LR2-5, the Host of Euryarchaeal Virus HFTV1. Front Microbiol 2021; 12:625599. [PMID: 33664716 PMCID: PMC7921747 DOI: 10.3389/fmicb.2021.625599] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 01/28/2021] [Indexed: 01/14/2023] Open
Abstract
Hypersaline environments are the source of many viruses infecting different species of halophilic euryarchaea. Information on infection mechanisms of archaeal viruses is scarce, due to the lack of genetically accessible virus–host models. Recently, a new archaeal siphovirus, Haloferax tailed virus 1 (HFTV1), was isolated together with its host belonging to the genus Haloferax, but it is not infectious on the widely used model euryarcheon Haloferax volcanii. To gain more insight into the biology of HFTV1 host strain LR2-5, we studied characteristics that might play a role in its virus susceptibility: growth-dependent motility, surface layer, filamentous surface structures, and cell shape. Its genome sequence showed that LR2-5 is a new strain of Haloferax gibbonsii. LR2-5 lacks obvious viral defense systems, such as CRISPR-Cas, and the composition of its cell surface is different from Hfx. volcanii, which might explain the different viral host range. This work provides first deep insights into the relationship between the host of halovirus HFTV1 and other members of the genus Haloferax. Given the close relationship to the genetically accessible Hfx. volcanii, LR2-5 has high potential as a new model for virus–host studies in euryarchaea.
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Affiliation(s)
- Colin Tittes
- Archaeal Virus-Host Interactions, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Sabine Schwarzer
- Archaeal Virus-Host Interactions, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Friedhelm Pfeiffer
- Computational Biology Group, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Mike Dyall-Smith
- Computational Biology Group, Max Planck Institute of Biochemistry, Martinsried, Germany.,Department of Veterinary Biosciences, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville, VIC, Australia
| | | | - Hanna M Oksanen
- Molecular and Integrative Biosciences Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Tessa E F Quax
- Archaeal Virus-Host Interactions, Faculty of Biology, University of Freiburg, Freiburg, Germany
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33
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Collins M, Afolayan S, Igiraneza AB, Schiller H, Krespan E, Beiting DP, Dyall-Smith M, Pfeiffer F, Pohlschroder M. Mutations Affecting HVO_1357 or HVO_2248 Cause Hypermotility in Haloferax volcanii, Suggesting Roles in Motility Regulation. Genes (Basel) 2020; 12:58. [PMID: 33396553 PMCID: PMC7824242 DOI: 10.3390/genes12010058] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 12/28/2020] [Accepted: 12/29/2020] [Indexed: 12/18/2022] Open
Abstract
Motility regulation plays a key role in prokaryotic responses to environmental stimuli. Here, we used a motility screen and selection to isolate hypermotile Haloferax volcanii mutants from a transposon insertion library. Whole genome sequencing revealed that hypermotile mutants were predominantly affected in two genes that encode HVO_1357 and HVO_2248. Alterations of these genes comprised not only transposon insertions but also secondary genome alterations. HVO_1357 contains a domain that was previously identified in the regulation of bacteriorhodopsin transcription, as well as other domains frequently found in two-component regulatory systems. The genes adjacent to hvo_1357 encode a sensor box histidine kinase and a response regulator, key players of a two-component regulatory system. None of the homologues of HVO_2248 have been characterized, nor does it contain any of the assigned InterPro domains. However, in a significant number of Haloferax species, the adjacent gene codes for a chemotaxis receptor/transducer. Our results provide a foundation for characterizing the root causes underlying Hfx. volcanii hypermotility.
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Affiliation(s)
- Michiyah Collins
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA; (M.C.); (S.A.); (A.B.I.); (H.S.)
| | - Simisola Afolayan
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA; (M.C.); (S.A.); (A.B.I.); (H.S.)
| | - Aime B. Igiraneza
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA; (M.C.); (S.A.); (A.B.I.); (H.S.)
| | - Heather Schiller
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA; (M.C.); (S.A.); (A.B.I.); (H.S.)
| | - Elise Krespan
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (E.K.); (D.P.B.)
| | - Daniel P. Beiting
- Department of Pathobiology, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; (E.K.); (D.P.B.)
| | - Mike Dyall-Smith
- Veterinary Biosciences, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Parkville 3010, Australia;
- Computational Biology Group, Max-Planck-Institute of Biochemistry, 82152 Martinsried, Germany;
| | - Friedhelm Pfeiffer
- Computational Biology Group, Max-Planck-Institute of Biochemistry, 82152 Martinsried, Germany;
| | - Mechthild Pohlschroder
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA; (M.C.); (S.A.); (A.B.I.); (H.S.)
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Cockram C, Thierry A, Gorlas A, Lestini R, Koszul R. Euryarchaeal genomes are folded into SMC-dependent loops and domains, but lack transcription-mediated compartmentalization. Mol Cell 2020; 81:459-472.e10. [PMID: 33382984 DOI: 10.1016/j.molcel.2020.12.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 10/01/2020] [Accepted: 12/07/2020] [Indexed: 12/26/2022]
Abstract
Hi-C has become a routine method for probing the 3D organization of genomes. However, when applied to prokaryotes and archaea, the current protocols are expensive and limited in their resolution. We develop a cost-effective Hi-C protocol to explore chromosome conformations of these two kingdoms at the gene or operon level. We first validate it on E. coli and V. cholera, generating sub-kilobase-resolution contact maps, and then apply it to the euryarchaeota H. volcanii, Hbt. salinarum, and T. kodakaraensis. With a resolution of up to 1 kb, we explore the diversity of chromosome folding in this phylum. In contrast to crenarchaeota, these euryarchaeota lack (active/inactive) compartment-like structures. Instead, their genomes are composed of self-interacting domains and chromatin loops. In H. volcanii, these structures are regulated by transcription and the archaeal structural maintenance of chromosomes (SMC) protein, further supporting the ubiquitous role of these processes in shaping the higher-order organization of genomes.
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Affiliation(s)
- Charlotte Cockram
- Institut Pasteur, Unité Régulation Spatiale des Génomes, CNRS UMR 3525, 75015 Paris, France
| | - Agnès Thierry
- Institut Pasteur, Unité Régulation Spatiale des Génomes, CNRS UMR 3525, 75015 Paris, France
| | - Aurore Gorlas
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Roxane Lestini
- Laboratoire d'Optique et Biosciences, École Polytechnique, CNRS UMR7645 - INSERM U1182, IP Paris, 91128 Palaiseau Cedex, France
| | - Romain Koszul
- Institut Pasteur, Unité Régulation Spatiale des Génomes, CNRS UMR 3525, 75015 Paris, France.
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Makkay AM, Louyakis AS, Ram-Mohan N, Gophna U, Gogarten JP, Papke RT. Insights into gene expression changes under conditions that facilitate horizontal gene transfer (mating) of a model archaeon. Sci Rep 2020; 10:22297. [PMID: 33339886 PMCID: PMC7749143 DOI: 10.1038/s41598-020-79296-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 11/19/2020] [Indexed: 12/16/2022] Open
Abstract
Horizontal gene transfer is a means by which bacteria, archaea, and eukaryotes are able to trade DNA within and between species. While there are a variety of mechanisms through which this genetic exchange can take place, one means prevalent in the archaeon Haloferax volcanii involves the transient formation of cytoplasmic bridges between cells and is referred to as mating. This process can result in the exchange of very large fragments of DNA between the participating cells. Genes governing the process of mating, including triggers to initiate mating, mechanisms of cell fusion, and DNA exchange, have yet to be characterized. We used a transcriptomic approach to gain a more detailed knowledge of how mating might transpire. By examining the differential expression of genes expressed in cells harvested from mating conditions on a filter over time and comparing them to those expressed in a shaking culture, we were able to identify genes and pathways potentially associated with mating. These analyses provide new insights into both the mechanisms and barriers of mating in Hfx. volcanii.
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Affiliation(s)
- Andrea M Makkay
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
| | - Artemis S Louyakis
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
| | - Nikhil Ram-Mohan
- Department of Emergency Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Uri Gophna
- The Shmunis School of Biomedicine and Cancer Research, Faculty of Life Sciences, Tel Aviv University, P.O. Box 39040, 6997801, Tel Aviv, Israel
| | - J Peter Gogarten
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA.,Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA
| | - R Thane Papke
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA.
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36
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Schiller H, Schulze S, Mutan Z, de Vaulx C, Runcie C, Schwartz J, Rados T, Bisson Filho AW, Pohlschroder M. Haloferax volcanii Immersed Liquid Biofilms Develop Independently of Known Biofilm Machineries and Exhibit Rapid Honeycomb Pattern Formation. mSphere 2020; 5:e00976-20. [PMID: 33328348 PMCID: PMC7771232 DOI: 10.1128/msphere.00976-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 11/19/2020] [Indexed: 12/21/2022] Open
Abstract
The ability to form biofilms is shared by many microorganisms, including archaea. Cells in a biofilm are encased in extracellular polymeric substances that typically include polysaccharides, proteins, and extracellular DNA, conferring protection while providing a structure that allows for optimal nutrient flow. In many bacteria, flagella and evolutionarily conserved type IV pili are required for the formation of biofilms on solid surfaces or floating at the air-liquid interface of liquid media. Similarly, in many archaea it has been demonstrated that type IV pili and, in a subset of these species, archaella are required for biofilm formation on solid surfaces. Additionally, in the model archaeon Haloferax volcanii, chemotaxis and AglB-dependent glycosylation play important roles in this process. H. volcanii also forms immersed biofilms in liquid cultures poured into petri dishes. This study reveals that mutants of this haloarchaeon that interfere with the biosynthesis of type IV pili or archaella, as well as a chemotaxis-targeting transposon and aglB deletion mutants, lack obvious defects in biofilms formed in liquid cultures. Strikingly, we have observed that these liquid-based biofilms are capable of rearrangement into honeycomb-like patterns that rapidly form upon removal of the petri dish lid, a phenomenon that is not dependent on changes in light or oxygen concentration but can be induced by controlled reduction of humidity. Taken together, this study demonstrates that H. volcanii requires novel, unidentified strategies for immersed liquid biofilm formation and also exhibits rapid structural rearrangements.IMPORTANCE This first molecular biological study of archaeal immersed liquid biofilms advances our basic biological understanding of the model archaeon Haloferax volcanii Data gleaned from this study also provide an invaluable foundation for future studies to uncover components required for immersed liquid biofilms in this haloarchaeon and also potentially for liquid biofilm formation in general, which is poorly understood compared to the formation of biofilms on surfaces. Moreover, this first description of rapid honeycomb pattern formation is likely to yield novel insights into the underlying structural architecture of extracellular polymeric substances and cells within immersed liquid biofilms.
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Affiliation(s)
- Heather Schiller
- Department of Biology, Leidy Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Stefan Schulze
- Department of Biology, Leidy Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Zuha Mutan
- Department of Biology, Leidy Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Charlotte de Vaulx
- Department of Biology, Leidy Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Catalina Runcie
- Department of Biology, Leidy Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Jessica Schwartz
- Department of Biology, Leidy Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Theopi Rados
- Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, Massachusetts, USA
| | - Alexandre W Bisson Filho
- Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, Massachusetts, USA
| | - Mechthild Pohlschroder
- Department of Biology, Leidy Laboratories, University of Pennsylvania, Philadelphia, Pennsylvania, USA
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37
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Pérez-Arnaiz P, Dattani A, Smith V, Allers T. Haloferax volcanii-a model archaeon for studying DNA replication and repair. Open Biol 2020; 10:200293. [PMID: 33259746 PMCID: PMC7776575 DOI: 10.1098/rsob.200293] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 11/09/2020] [Indexed: 12/16/2022] Open
Abstract
The tree of life shows the relationship between all organisms based on their common ancestry. Until 1977, it comprised two major branches: prokaryotes and eukaryotes. Work by Carl Woese and other microbiologists led to the recategorization of prokaryotes and the proposal of three primary domains: Eukarya, Bacteria and Archaea. Microbiological, genetic and biochemical techniques were then needed to study the third domain of life. Haloferax volcanii, a halophilic species belonging to the phylum Euryarchaeota, has provided many useful tools to study Archaea, including easy culturing methods, genetic manipulation and phenotypic screening. This review will focus on DNA replication and DNA repair pathways in H. volcanii, how this work has advanced our knowledge of archaeal cellular biology, and how it may deepen our understanding of bacterial and eukaryotic processes.
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Affiliation(s)
| | | | | | - Thorsten Allers
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham, UK
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38
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Raut P, Glass JB, Lieberman RL. Archaeal roots of intramembrane aspartyl protease siblings signal peptide peptidase and presenilin. Proteins 2020; 89:232-241. [PMID: 32935885 DOI: 10.1002/prot.26009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/27/2020] [Accepted: 09/13/2020] [Indexed: 12/21/2022]
Abstract
Signal peptides help newly synthesized proteins reach the cell membrane or be secreted. As part of a biological process key to immune response and surveillance in humans, and associated with diseases, for example, Alzheimer, remnant signal peptides and other transmembrane segments are proteolyzed by the intramembrane aspartyl protease (IAP) enzyme family. Here, we identified IAP orthologs throughout the tree of life. In addition to eukaryotes, IAPs are encoded in metabolically diverse archaea from a wide range of environments. We found three distinct clades of archaeal IAPs: (a) Euryarchaeota (eg, halophilic Halobacteriales, methanogenic Methanosarcinales and Methanomicrobiales, marine Poseidoniales, acidophilic Thermoplasmatales, hyperthermophilic Archaeoglobus spp.), (b) DPANN, and (c) Bathyarchaeota, Crenarchaeota, and Asgard. IAPs were also present in bacterial genomes from uncultivated members of Candidate Phylum Radiation, perhaps due to horizontal gene transfer from DPANN archaeal lineages. Sequence analysis of the catalytic motif YD…GXGD (where X is any amino acid) in IAPs from archaea and bacteria reveals WD in Lokiarchaeota and many residue types in the X position. Gene neighborhood analysis in halophilic archaea shows IAP genes near corrinoid transporters (btuCDF genes). In marine Euryarchaeota, a putative BtuF-like domain is found in N-terminus of the IAP gene, suggesting a role for these IAPs in metal ion cofactor or other nutrient scavenging. Interestingly, eukaryotic IAP family members appear to have evolved either from Euryarchaeota or from Asgard archaea. Taken together, our phylogenetic and bioinformatics analysis should prompt experiments to probe the biological roles of IAPs in prokaryotic secretomes.
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Affiliation(s)
- Priyam Raut
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Jennifer B Glass
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA.,School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Raquel L Lieberman
- School of Chemistry & Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, USA
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39
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Davis CR, Johnson CH, Robertson JB. A bioluminescent reporter for the halophilic archaeon Haloferax volcanii. Extremophiles 2020; 24:773-785. [PMID: 32749548 PMCID: PMC7462420 DOI: 10.1007/s00792-020-01193-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 07/21/2020] [Indexed: 12/19/2022]
Abstract
Haloarchaea have evolved to thrive in hypersaline environments. Haloferax volcanii is of particular interest due to its genetic tractability; however, few in vivo reporters exist for halophiles. Haloarchaeal proteins evolved characteristics that promote proper folding and function at high salt concentrations, but many mesophilic reporter proteins lack these characteristics. Mesophilic proteins that acquire salt-stabilizing mutations, however, can lead to proper function in haloarchaea. Using laboratory-directed evolution, we developed and demonstrated an in vivo luciferase that functions in the hypersaline cytosol of H. volcanii.
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Affiliation(s)
- Chris R Davis
- Department of Biology, Middle Tennessee State University, Murfreesboro, TN, USA
| | - Carl H Johnson
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - J Brian Robertson
- Department of Biology, Middle Tennessee State University, Murfreesboro, TN, USA.
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40
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Stachler AE, Wörtz J, Alkhnbashi OS, Turgeman-Grott I, Smith R, Allers T, Backofen R, Gophna U, Marchfelder A. Adaptation induced by self-targeting in a type I-B CRISPR-Cas system. J Biol Chem 2020; 295:13502-13515. [PMID: 32723866 PMCID: PMC7521656 DOI: 10.1074/jbc.ra120.014030] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 07/15/2020] [Indexed: 11/06/2022] Open
Abstract
Haloferax volcanii is, to our knowledge, the only prokaryote known to tolerate CRISPR-Cas-mediated damage to its genome in the WT background; the resulting cleavage of the genome is repaired by homologous recombination restoring the WT version. In mutant Haloferax strains with enhanced self-targeting, cell fitness decreases and microhomology-mediated end joining becomes active, generating deletions in the targeted gene. Here we use self-targeting to investigate adaptation in H. volcanii CRISPR-Cas type I-B. We show that self-targeting and genome breakage events that are induced by self-targeting, such as those catalyzed by active transposases, can generate DNA fragments that are used by the CRISPR-Cas adaptation machinery for integration into the CRISPR loci. Low cellular concentrations of self-targeting crRNAs resulted in acquisition of large numbers of spacers originating from the entire genomic DNA. In contrast, high concentrations of self-targeting crRNAs resulted in lower acquisition that was mostly centered on the targeting site. Furthermore, we observed naïve spacer acquisition at a low level in WT Haloferax cells and with higher efficiency upon overexpression of the Cas proteins Cas1, Cas2, and Cas4. Taken together, these findings indicate that naïve adaptation is a regulated process in H. volcanii that operates at low basal levels and is induced by DNA breaks.
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Affiliation(s)
| | | | - Omer S Alkhnbashi
- Bioinformatics Group, Department of Computer Science, University of Freiburg, Freiburg, Germany
| | - Israela Turgeman-Grott
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Rachel Smith
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Thorsten Allers
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Rolf Backofen
- Bioinformatics Group, Department of Computer Science, University of Freiburg, Freiburg, Germany; Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Uri Gophna
- Department of Molecular Microbiology and Biotechnology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
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41
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Niessen N, Soppa J. Regulated Iron Siderophore Production of the Halophilic Archaeon Haloferax volcanii. Biomolecules 2020; 10:biom10071072. [PMID: 32709147 PMCID: PMC7407949 DOI: 10.3390/biom10071072] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 07/02/2020] [Accepted: 07/13/2020] [Indexed: 01/04/2023] Open
Abstract
Iron is part of many redox and other enzymes and, thus, it is essential for all living beings. Many oxic environments have extremely low concentrations of free iron. Therefore, many prokaryotic species evolved siderophores, i.e., small organic molecules that complex Fe3+ with very high affinity. Siderophores of bacteria are intensely studied, in contrast to those of archaea. The haloarchaeon Haloferax volcanii contains a gene cluster that putatively encodes siderophore biosynthesis genes, including four iron uptake chelate (iuc) genes. Underscoring this hypothesis, Northern blot analyses revealed that a hexacistronic transcript is generated that is highly induced under iron starvation. A quadruple iuc deletion mutant was generated, which had a growth defect solely at very low concentrations of Fe3+, not Fe2+. Two experimental approaches showed that the wild type produced and exported an Fe3+-specific siderophore under low iron concentrations, in contrast to the iuc deletion mutant. Bioinformatic analyses revealed that haloarchaea obtained the gene cluster by lateral transfer from bacteria and enabled the prediction of enzymatic functions of all six gene products. Notably, a biosynthetic pathway is proposed that starts with aspartic acid, uses several group donors and citrate, and leads to the hydroxamate siderophore Schizokinen.
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Affiliation(s)
- Natalie Niessen
- Institute for Molecular Biosciences, Goethe-University, Biocentre, Max-von-Laue-str. 9, D-60439 Frankfurt, Germany;
- Campus Callaghan, Faculty of Health and Medicine, School of Medicine and Public Health, Hunter Medical Research Institute, University of Newcastle, Newcastle, NSW 2308, Australia
| | - Jörg Soppa
- Institute for Molecular Biosciences, Goethe-University, Biocentre, Max-von-Laue-str. 9, D-60439 Frankfurt, Germany;
- Correspondence:
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42
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The Archaeal Proteome Project advances knowledge about archaeal cell biology through comprehensive proteomics. Nat Commun 2020; 11:3145. [PMID: 32561711 PMCID: PMC7305310 DOI: 10.1038/s41467-020-16784-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Accepted: 05/18/2020] [Indexed: 11/08/2022] Open
Abstract
While many aspects of archaeal cell biology remain relatively unexplored, systems biology approaches like mass spectrometry (MS) based proteomics offer an opportunity for rapid advances. Unfortunately, the enormous amount of MS data generated often remains incompletely analyzed due to a lack of sophisticated bioinformatic tools and field-specific biological expertise for data interpretation. Here we present the initiation of the Archaeal Proteome Project (ArcPP), a community-based effort to comprehensively analyze archaeal proteomes. Starting with the model archaeon Haloferax volcanii, we reanalyze MS datasets from various strains and culture conditions. Optimized peptide spectrum matching, with strict control of false discovery rates, facilitates identifying > 72% of the reference proteome, with a median protein sequence coverage of 51%. These analyses, together with expert knowledge in diverse aspects of cell biology, provide meaningful insights into processes such as N-terminal protein maturation, N-glycosylation, and metabolism. Altogether, ArcPP serves as an invaluable blueprint for comprehensive prokaryotic proteomics.
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43
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Estimation of the Genome-Wide Mutation Rate and Spectrum in the Archaeal Species Haloferax volcanii. Genetics 2020; 215:1107-1116. [PMID: 32513815 DOI: 10.1534/genetics.120.303299] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 05/26/2020] [Indexed: 12/26/2022] Open
Abstract
Organisms adapted to life in extreme habitats (extremophiles) can further our understanding of the mechanisms of genetic stability, particularly replication and repair. Despite the harsh environmental conditions they endure, these extremophiles represent a great deal of the Earth's biodiversity. Here, for the first time in a member of the archaeal domain, we report a genome-wide assay of spontaneous mutations in the halophilic species Haloferax volcanii using a direct and unbiased method: mutation accumulation experiments combined with deep whole-genome sequencing. H. volcanii is a key model organism not only for the study of halophilicity, but also for archaeal biology in general. Our methods measure the genome-wide rate, spectrum, and spatial distribution of spontaneous mutations. The estimated base substitution rate of 3.15 × 10-10 per site per generation, or 0.0012 per genome per generation, is similar to the value found in mesophilic prokaryotes (optimal growth at ∼20-45°). This study contributes to a comprehensive phylogenetic view of how evolutionary forces and molecular mechanisms shape the rate and molecular spectrum of mutations across the tree of life.
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44
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The complex phylogenetic relationships of a 4mC/6mA DNA methyltransferase in prokaryotes. Mol Phylogenet Evol 2020; 149:106837. [PMID: 32304827 DOI: 10.1016/j.ympev.2020.106837] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 01/30/2020] [Accepted: 04/09/2020] [Indexed: 01/04/2023]
Abstract
DNA methyltransferases are proteins that modify DNA via attachment of methyl groups to nucleobases and are ubiquitous across the bacterial, archaeal, and eukaryotic domains of life. Here, we investigated the complex evolutionary history of the large and consequential 4mC/6mA DNA methyltransferase protein family using phylogenetic reconstruction of amino acid sequences. We present a well-supported phylogeny of this family based on systematic sampling of taxa across superphyla of bacteria and archaea. We compared the phylogeny to a current representation of the species tree of life and found that the 4mC/6mA methyltransferase family has a strikingly complex evolutionary history that likely began sometime after the last universal common ancestor of life diverged into the bacterial and archaeal lineages and probably involved many horizontal gene transfers within and between domains. Despite the complexity of its evolutionary history, we inferred that only one significant shift in molecular evolutionary rate characterizes the diversification of this protein family.
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45
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Jüttner M, Weiß M, Ostheimer N, Reglin C, Kern M, Knüppel R, Ferreira-Cerca S. A versatile cis-acting element reporter system to study the function, maturation and stability of ribosomal RNA mutants in archaea. Nucleic Acids Res 2020; 48:2073-2090. [PMID: 31828323 PMCID: PMC7038931 DOI: 10.1093/nar/gkz1156] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 11/12/2019] [Accepted: 11/30/2019] [Indexed: 12/17/2022] Open
Abstract
General molecular principles of ribosome biogenesis have been well explored in bacteria and eukaryotes. Collectively, these studies have revealed important functional differences and few similarities between these processes. Phylogenetic studies suggest that the information processing machineries from archaea and eukaryotes are evolutionary more closely related than their bacterial counterparts. These observations raise the question of how ribosome synthesis in archaea may proceed in vivo. In this study, we describe a versatile plasmid-based cis-acting reporter system allowing to analyze in vivo the consequences of ribosomal RNA mutations in the model archaeon Haloferax volcanii. Applying this system, we provide evidence that the bulge-helix-bulge motif enclosed within the ribosomal RNA processing stems is required for the formation of archaeal-specific circular-pre-rRNA intermediates and mature rRNAs. In addition, we have collected evidences suggesting functional coordination of the early steps of ribosome synthesis in H. volcanii. Together our investigation describes a versatile platform allowing to generate and functionally analyze the fate of diverse rRNA variants, thereby paving the way to better understand the cis-acting molecular determinants necessary for archaeal ribosome synthesis, maturation, stability and function.
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Affiliation(s)
- Michael Jüttner
- Biochemistry III – Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Matthias Weiß
- Biochemistry III – Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Nina Ostheimer
- Biochemistry III – Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Corinna Reglin
- Biochemistry III – Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Michael Kern
- Biochemistry III – Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Robert Knüppel
- Biochemistry III – Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
| | - Sébastien Ferreira-Cerca
- Biochemistry III – Institute for Biochemistry, Genetics and Microbiology, University of Regensburg, Universitätsstraße 31, 93053 Regensburg, Germany
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46
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Pfeiffer F, Losensky G, Marchfelder A, Habermann B, Dyall‐Smith M. Whole-genome comparison between the type strain of Halobacterium salinarum (DSM 3754 T ) and the laboratory strains R1 and NRC-1. Microbiologyopen 2020; 9:e974. [PMID: 31797576 PMCID: PMC7002104 DOI: 10.1002/mbo3.974] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 11/08/2019] [Accepted: 11/09/2019] [Indexed: 01/04/2023] Open
Abstract
Halobacterium salinarum is an extremely halophilic archaeon that is widely distributed in hypersaline environments and was originally isolated as a spoilage organism of salted fish and hides. The type strain 91-R6 (DSM 3754T ) has seldom been studied and its genome sequence has only recently been determined by our group. The exact relationship between the type strain and two widely used model strains, NRC-1 and R1, has not been described before. The genome of Hbt. salinarum strain 91-R6 consists of a chromosome (2.17 Mb) and two large plasmids (148 and 102 kb, with 39,230 bp being duplicated). Cytosine residues are methylated (m4 C) within CTAG motifs. The genomes of type and laboratory strains are closely related, their chromosomes sharing average nucleotide identity (ANIb) values of 98% and in silico DNA-DNA hybridization (DDH) values of 95%. The chromosomes are completely colinear, do not show genome rearrangement, and matching segments show <1% sequence difference. Among the strain-specific sequences are three large chromosomal replacement regions (>10 kb). The well-studied AT-rich island (61 kb) of the laboratory strains is replaced by a distinct AT-rich sequence (47 kb) in 91-R6. Another large replacement (91-R6: 78 kb, R1: 44 kb) codes for distinct homologs of proteins involved in motility and N-glycosylation. Most (107 kb) of plasmid pHSAL1 (91-R6) is very closely related to part of plasmid pHS3 (R1) and codes for essential genes (e.g. arginine-tRNA ligase and the pyrimidine biosynthesis enzyme aspartate carbamoyltransferase). Part of pHS3 (42.5 kb total) is closely related to the largest strain-specific sequence (164 kb) in the type strain chromosome. Genome sequencing unraveled the close relationship between the Hbt. salinarum type strain and two well-studied laboratory strains at the DNA and protein levels. Although an independent isolate, the type strain shows a remarkably low evolutionary difference to the laboratory strains.
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Affiliation(s)
- Friedhelm Pfeiffer
- Computational Biology GroupMax‐Planck‐Institute of BiochemistryMartinsriedGermany
| | - Gerald Losensky
- Microbiology and ArchaeaDepartment of BiologyTechnische Universität DarmstadtDarmstadtGermany
| | | | - Bianca Habermann
- Computational Biology GroupMax‐Planck‐Institute of BiochemistryMartinsriedGermany
- CNRSIBDM UMR 7288Aix Marseille UniversitéMarseilleFrance
| | - Mike Dyall‐Smith
- Computational Biology GroupMax‐Planck‐Institute of BiochemistryMartinsriedGermany
- Veterinary BiosciencesFaculty of Veterinary and Agricultural SciencesUniversity of MelbourneParkvilleVic.Australia
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47
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Haque RU, Paradisi F, Allers T. Haloferax volcanii for biotechnology applications: challenges, current state and perspectives. Appl Microbiol Biotechnol 2019; 104:1371-1382. [PMID: 31863144 PMCID: PMC6985049 DOI: 10.1007/s00253-019-10314-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 12/05/2019] [Accepted: 12/10/2019] [Indexed: 01/08/2023]
Abstract
Haloferax volcanii is an obligate halophilic archaeon with its origin in the Dead Sea. Simple laboratory culture conditions and a wide range of genetic tools have made it a model organism for studying haloarchaeal cell biology. Halophilic enzymes of potential interest to biotechnology have opened up the application of this organism in biocatalysis, bioremediation, nanobiotechnology, bioplastics and the biofuel industry. Functionally active halophilic proteins can be easily expressed in a halophilic environment, and an extensive genetic toolkit with options for regulated protein overexpression has allowed the purification of biotechnologically important enzymes from different halophiles in H. volcanii. However, corrosion mediated damage caused to stainless-steel bioreactors by high salt concentrations and a tendency to form biofilms when cultured in high volume are some of the challenges of applying H. volcanii in biotechnology. The ability to employ expressed active proteins in immobilized cells within a porous biocompatible matrix offers new avenues for exploiting H. volcanii in biotechnology. This review critically evaluates the various application potentials, challenges and toolkits available for using this extreme halophilic organism in biotechnology.
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Affiliation(s)
- R U Haque
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK.,School of Chemistry, University Park, University of Nottingham, Nottingham, NG7 2RD, UK.,Warwick Integrative Synthetic Biology Centre, School of Life Sciences, Gibbet Hill Campus, University of Warwick, Coventry, CV4 7AL, UK
| | - F Paradisi
- School of Chemistry, University Park, University of Nottingham, Nottingham, NG7 2RD, UK.,Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012, Bern, Switzerland
| | - T Allers
- School of Life Sciences, Queens Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK.
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48
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Wolters M, Borst A, Pfeiffer F, Soppa J. Bioinformatic and genetic characterization of three genes localized adjacent to the major replication origin of Haloferax volcanii. FEMS Microbiol Lett 2019; 366:5643889. [DOI: 10.1093/femsle/fnz238] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 11/25/2019] [Indexed: 11/13/2022] Open
Abstract
ABSTRACT
In haloarchaea, a cluster of three genes is localized directly adjacent to the major replication origin, and, hence, the encoded proteins were annotated as ‘origin-associated proteins’ (Oap). However, prior to this study, no experimental data were available for these conserved hypothetical proteins. Bioinformatic analyses were performed, which unraveled, 1) that the amino acid composition of all three proteins deviate from the average, 2) that OapA is a GTP-binding protein, 3) that OapC has an N-terminal zinc-finger motif, and 4) that the sequences of OapA and OapB are highly conserved while OapC conservation is restricted to short terminal regions. Surprisingly, transcript analyses revealed a complex expression pattern of the oap genes, despite their close proximity. Based on the high degree of conservation in haloarchaea it could be expected that one or more of the oap genes might be essential. However, in frame deletion mutants of all three genes could be readily generated, were viable, and had no growth phenotype. In addition, quantification of the chromsome copy numbers revealed no significant differences between the wild-type and the three mutants. In summary, experimental evidence is inconsistent with Oap proteins being essential for or involved in key steps of DNA replication.
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Affiliation(s)
- Maike Wolters
- Biocentre, Institute for Molecular Biosciences, Goethe-University, Max-von-Laue-Str. 9, Frankfurt D-60438, Germany
| | - Andreas Borst
- Biocentre, Institute for Molecular Biosciences, Goethe-University, Max-von-Laue-Str. 9, Frankfurt D-60438, Germany
| | - Friedhelm Pfeiffer
- Computational Biology Group, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jörg Soppa
- Biocentre, Institute for Molecular Biosciences, Goethe-University, Max-von-Laue-Str. 9, Frankfurt D-60438, Germany
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49
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Abstract
Despite the typical human notion that the Earth is a habitable planet, over three quarters of our planet is uninhabitable by us without assistance. The organisms that live and thrive in these “inhospitable” environments are known by the name extremophiles and are found in all Domains of Life. Despite our general lack of knowledge about them, they have already assisted humans in many ways and still have much more to give. In this review, I describe how they have adapted to live/thrive/survive in their niches, helped scientists unlock major scientific discoveries, advance the field of biotechnology, and inform us about the boundaries of Life and where we might find it in the Universe.
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Affiliation(s)
- James A Coker
- Department of Sciences, University of Maryland Global Campus, Adelphi, MD, USA
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Jevtić Ž, Stoll B, Pfeiffer F, Sharma K, Urlaub H, Marchfelder A, Lenz C. The Response of Haloferax volcanii to Salt and Temperature Stress: A Proteome Study by Label-Free Mass Spectrometry. Proteomics 2019; 19:e1800491. [PMID: 31502396 DOI: 10.1002/pmic.201800491] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 08/27/2019] [Indexed: 01/23/2023]
Abstract
In-depth proteome analysis of the haloarchaeal model organism Haloferax volcanii has been performed under standard, low/high salt, and low/high temperature conditions using label-free mass spectrometry. Qualitative analysis of protein identification data from high-pH/reversed-phase fractionated samples indicates 61.1% proteome coverage (2509 proteins), which is close to the maximum recorded values in archaea. Identified proteins match to the predicted proteome in their physicochemical properties, with only a small bias against low-molecular-weight and membrane-associated proteins. Cells grown under low and high salt stress as well as low and high temperature stress are quantitatively compared to standard cultures by sequential window acquisition of all theoretical mass spectra (SWATH-MS). A total of 2244 proteins, or 54.7% of the predicted proteome, are quantified across all conditions at high reproducibility, which allowed for global analysis of protein expression changes under these stresses. Of these, 2034 are significantly regulated under at least one stress condition. KEGG pathway enrichment analysis shows that several major cellular pathways are part of H. volcanii's universal stress response. In addition, specific pathways (purine, cobalamin, and tryptophan) are affected by temperature stress. The most strongly downregulated proteins under all stress conditions, zinc finger protein HVO_2753 and ribosomal protein S14, are found oppositely regulated to their immediate genetic neighbors from the same operon.
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Affiliation(s)
- Živojin Jevtić
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Faßberg 11, Göttingen, 37077, Germany
| | | | - Friedhelm Pfeiffer
- Computational Biology Group, Max Planck Institute of Biochemistry, Martinsried, 82152, Germany
| | - Kundan Sharma
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Faßberg 11, Göttingen, 37077, Germany
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Faßberg 11, Göttingen, 37077, Germany.,Institute of Clinical Chemistry, University Medical Center Göttingen, Göttingen, 37075, Germany
| | | | - Christof Lenz
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Faßberg 11, Göttingen, 37077, Germany.,Institute of Clinical Chemistry, University Medical Center Göttingen, Göttingen, 37075, Germany
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