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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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2
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Zhang S, Chen F, Ke J, Hao Y, Pan R, Hong T, Dai Y, Chen S. Hly176B, a low-salt tolerant halolysin from the haloarchaeon Haloarchaeobius sp. FL176. World J Microbiol Biotechnol 2023; 39:189. [PMID: 37157004 DOI: 10.1007/s11274-023-03632-1] [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: 12/07/2022] [Accepted: 04/26/2023] [Indexed: 05/10/2023]
Abstract
Extracellular proteases of haloarchaea can adapt to high concentrations of NaCl and can find useful applications in industrial or biotechnology processes where hypersaline conditions are desired. The diversity of extracellular proteases produced by haloarchaea is largely unknown though the genomes of many species have been sequenced and are publicly available. In this study, a gene encoding the extracellular protease Hly176B from the haloarchaeon Haloarchaeobius sp. FL176 was cloned and expressed in Escherichia coli. A related gene homolog to hly176B, hly176A, from the same strain was also expressed in E.coli, but did not show any proteinase activity after the same renaturation process. Therefore, we focus on the enzymatic properties of the Hly176B. The catalytic triad Asp-His-Ser was confirmed via site-directed mutagenesis, indicating that Hly176B belongs to the class of serine proteases (halolysin). Unlike previously reported extracellular proteases from haloarchaea, the Hly176B remained active for a relatively long time in an almost salt-free solution. In addition, the Hly176B displayed prominent tolerance to some metal ions, surfactants and organic solvents, and exerts its highest enzyme activity at 40 °C, pH 8.0 and 0.5 M NaCl. Therefore, this study enriches our knowledge of extracellular proteases and expands their applications for various industrial uses.
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Affiliation(s)
- Shenao Zhang
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Feilong Chen
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
- Anhui Jiaotianxiang Biological Technology Co., Ltd, Xuancheng, 242000, China
| | - Juntao Ke
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Yuling Hao
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Ruru Pan
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Tao Hong
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Yongpei Dai
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Shaoxing Chen
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China.
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 10010, China.
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3
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Synthesizing glycine betaine via choline oxidation pathway as an osmoprotectant strategy in Haloferacales. Gene 2022; 847:146886. [PMID: 36108788 DOI: 10.1016/j.gene.2022.146886] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/21/2022] [Accepted: 09/07/2022] [Indexed: 11/22/2022]
Abstract
The accumulation of organic compatible solutes, such as glycine betaine, is one of the osmoprotective strategies used by halophilic archaea to adapt to high salinity. The uptake of glycine betaine from the external environment using various transporters has been widely studied in different halophilic archaea. However, the de novo biosynthesis of glycine betaine and its distribution in halophilic archaea remain unclear. In this study, an extremely halophilic archaea strain, named Halorubrum sp. 2020YC2 and previously isolated from a salt-lake sample, was identified with complete choline oxidation pathway genes. Halorubrum sp. 2020YC2 could synthesize and accumulate 1.56-4.25 μmol per mg of protein of glycine betaine in a defined medium, with its content increasing along with increasing salinity. The intracellular content of glycine betaine remained relatively stable at different salinities when another exogenous solute such as trehalose was provided. The metabolic profile and transcriptional results strongly suggested that the intracellular glycine betaine was derived from serine, which came from the glycolytic intermediate 3-phosphoglycerate when glucose was used as the sole carbon source. Out of 205 available genomes of halophilic archaea, genes encoding the choline oxidation pathway were identified in 30 genomes, and more than half of the strains belonging to order Haloferacales contained the choline oxidation pathway. Phylogenetic analysis further indicated that this pathway evolved from halophilic Proteobacteria, and its absence in some genera indicated a possible gene loss event during evolution. The analysis of reported culture data of halophilic archaea strains eventually demonstrated that the presence of the choline oxidation pathway had no significant effects on the adaptation of Haloferacales to high salinity habitats. Therefore, the de novo biosynthesis of glycine betaine via the choline oxidation pathway could be an auxiliary osmoprotective strategy in halophilic archaea.
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4
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de Kok NAW, Driessen AJM. The catalytic and structural basis of archaeal glycerophospholipid biosynthesis. Extremophiles 2022; 26:29. [PMID: 35976526 PMCID: PMC9385802 DOI: 10.1007/s00792-022-01277-w] [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: 03/21/2022] [Accepted: 08/02/2022] [Indexed: 12/03/2022]
Abstract
Archaeal glycerophospholipids are the main constituents of the cytoplasmic membrane in the archaeal domain of life and fundamentally differ in chemical composition compared to bacterial phospholipids. They consist of isoprenyl chains ether-bonded to glycerol-1-phosphate. In contrast, bacterial glycerophospholipids are composed of fatty acyl chains ester-bonded to glycerol-3-phosphate. This largely domain-distinguishing feature has been termed the “lipid-divide”. The chemical composition of archaeal membranes contributes to the ability of archaea to survive and thrive in extreme environments. However, ether-bonded glycerophospholipids are not only limited to extremophiles and found also in mesophilic archaea. Resolving the structural basis of glycerophospholipid biosynthesis is a key objective to provide insights in the early evolution of membrane formation and to deepen our understanding of the molecular basis of extremophilicity. Many of the glycerophospholipid enzymes are either integral membrane proteins or membrane-associated, and hence are intrinsically difficult to study structurally. However, in recent years, the crystal structures of several key enzymes have been solved, while unresolved enzymatic steps in the archaeal glycerophospholipid biosynthetic pathway have been clarified providing further insights in the lipid-divide and the evolution of early life.
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Affiliation(s)
- Niels A W de Kok
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747AG, Groningen, The Netherlands
| | - Arnold J M Driessen
- Department of Molecular Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, 9747AG, Groningen, The Netherlands.
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5
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The Polar Fox Lagoon in Siberia harbours a community of Bathyarchaeota possessing the potential for peptide fermentation and acetogenesis. Antonie Van Leeuwenhoek 2022; 115:1229-1244. [PMID: 35947314 PMCID: PMC9534799 DOI: 10.1007/s10482-022-01767-z] [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: 05/13/2022] [Accepted: 07/18/2022] [Indexed: 11/05/2022]
Abstract
Archaea belonging to the phylum Bathyarchaeota are the predominant archaeal species in cold, anoxic marine sediments and additionally occur in a variety of habitats, both natural and man-made. Metagenomic and single-cell sequencing studies suggest that Bathyarchaeota may have a significant impact on the emissions of greenhouse gases into the atmosphere, either through direct production of methane or through the degradation of complex organic matter that can subsequently be converted into methane. This is especially relevant in permafrost regions where climate change leads to thawing of permafrost, making high amounts of stored carbon bioavailable. Here we present the analysis of nineteen draft genomes recovered from a sediment core metagenome of the Polar Fox Lagoon, a thermokarst lake located on the Bykovsky Peninsula in Siberia, Russia, which is connected to the brackish Tiksi Bay. We show that the Bathyarchaeota in this lake are predominantly peptide degraders, producing reduced ferredoxin from the fermentation of peptides, while degradation pathways for plant-derived polymers were found to be incomplete. Several genomes encoded the potential for acetogenesis through the Wood-Ljungdahl pathway, but methanogenesis was determined to be unlikely due to the lack of genes encoding the key enzyme in methanogenesis, methyl-CoM reductase. Many genomes lacked a clear pathway for recycling reduced ferredoxin. Hydrogen metabolism was also hardly found: one type 4e [NiFe] hydrogenase was annotated in a single MAG and no [FeFe] hydrogenases were detected. Little evidence was found for syntrophy through formate or direct interspecies electron transfer, leaving a significant gap in our understanding of the metabolism of these organisms.
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6
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The Osmoprotectant Switch of Potassium to Compatible Solutes in an Extremely Halophilic Archaea Halorubrum kocurii 2020YC7. Genes (Basel) 2022; 13:genes13060939. [PMID: 35741701 PMCID: PMC9222508 DOI: 10.3390/genes13060939] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/27/2022] [Accepted: 05/13/2022] [Indexed: 11/17/2022] Open
Abstract
The main osmoadaptive mechanisms of extremely halophilic archaea include the “salt-in” strategy and the “compatible solutes” strategy. Here we report the osmoadaptive mechanism of an extremely halophilic archaea H. kocurii 2020YC7, isolated from a high salt environment sample. Genomic data revealed that strain 2020YC7 harbors genes trkA, trkH, kch for K+ uptake, kefB for K+ output, treS for trehalose production from polysaccharide, and betaine/carnitine/choline transporter family gene for glycine betaine uptake. Strain 2020YC7 could accumulate 8.17 to 28.67 μmol/mg protein K+ in a defined medium, with its content increasing along with the increasing salinity from 100 to 200 g/L. When exogenous glycine betaine was added, glycine betaine functioned as the primary osmotic solute between 200 and 250 g/L NaCl, which was accumulated up to 15.27 mg/mg protein in 2020YC7 cells. RT-qPCR results completely confirmed these results. Notably, the concentrations of intracellular trehalose decreased from 5.26 to 2.61 mg/mg protein as the NaCl increased from 50 to 250 g/L. In combination with this result, the transcript level of gene treS, which catalyzes the production of trehalose from polysaccharide, was significantly up-regulated at 50–100 g/L NaCl. Therefore, trehalose does not act as an osmotic solute at high NaCl concentrations (more than 100 g/L) but at relatively low NaCl concentrations (50–100 g/L). And we propose that the degradation of cell wall polysaccharide, as a source of trehalose in a low-salt environment, may be one of the reasons for the obligate halophilic characteristics of strain 2020YC7.
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7
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Nature and bioprospecting of haloalkaliphilics: a review. World J Microbiol Biotechnol 2020; 36:66. [DOI: 10.1007/s11274-020-02841-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 04/14/2020] [Indexed: 01/07/2023]
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8
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A potassium chloride to glycine betaine osmoprotectant switch in the extreme halophile Halorhodospira halophila. Sci Rep 2020; 10:3383. [PMID: 32098991 PMCID: PMC7042295 DOI: 10.1038/s41598-020-59231-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 12/10/2019] [Indexed: 11/08/2022] Open
Abstract
Halophiles utilize two distinct osmoprotection strategies. The accumulation of organic compatible solutes such as glycine betaine does not perturb the functioning of cytoplasmic components, but represents a large investment of energy and carbon. KCl is an energetically attractive alternative osmoprotectant, but requires genome-wide modifications to establish a highly acidic proteome. Most extreme halophiles are optimized for the use of one of these two strategies. Here we examine the extremely halophilic Proteobacterium Halorhodospira halophila and report that medium K+ concentration dramatically alters its osmoprotectant use. When grown in hypersaline media containing substantial K+ concentrations, H. halophila accumulates molar concentrations of KCl. However, at limiting K+ concentrations the organism switches to glycine betaine as its major osmoprotectant. In contrast, the closely related organism Halorhodospira halochloris is limited to using compatible solutes. H. halophila performs both de novo synthesis and uptake of glycine betaine, matching the biosynthesis and transport systems encoded in its genome. The medium K+ concentration (~10 mM) at which the KCl to glycine betaine osmoprotectant switch in H. halophila occurs is near the K+ content of the lake from which it was isolated, supporting an ecological relevance of this osmoprotectant strategy.
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9
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Giani M, Garbayo I, Vílchez C, Martínez-Espinosa RM. Haloarchaeal Carotenoids: Healthy Novel Compounds from Extreme Environments. Mar Drugs 2019; 17:md17090524. [PMID: 31500208 PMCID: PMC6780574 DOI: 10.3390/md17090524] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 09/02/2019] [Accepted: 09/02/2019] [Indexed: 01/08/2023] Open
Abstract
Haloarchaea are halophilic microorganisms belonging to the archaea domain that inhabit salty environments (mainly soils and water) all over the world. Most of the genera included in this group can produce carotenoids at significant concentrations (even wild-type strains). The major carotenoid produced by the cells is bacterioruberin (and its derivatives), which is only produced by this kind of microbes and few bacteria, like Micrococcus roseus. Nevertheless, the understanding of carotenoid metabolism in haloarchaea, its regulation, and the roles of carotenoid derivatives in this group of extreme microorganisms remains mostly unrevealed. Besides, potential biotechnological uses of haloarchaeal pigments are poorly explored. This work summarises what it has been described so far about carotenoids from haloarchaea and their production at mid- and large-scale, paying special attention to the most recent findings on the potential uses of haloarchaeal pigments in biomedicine.
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Affiliation(s)
- Micaela Giani
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
| | - Inés Garbayo
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - Carlos Vílchez
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - Rosa María Martínez-Espinosa
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
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10
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Mokashe N, Chaudhari B, Patil U. Operative utility of salt-stable proteases of halophilic and halotolerant bacteria in the biotechnology sector. Int J Biol Macromol 2018; 117:493-522. [DOI: 10.1016/j.ijbiomac.2018.05.217] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/27/2018] [Accepted: 05/28/2018] [Indexed: 09/30/2022]
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11
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Gunde-Cimerman N, Plemenitaš A, Oren A. Strategies of adaptation of microorganisms of the three domains of life to high salt concentrations. FEMS Microbiol Rev 2018. [DOI: 10.1093/femsre/fuy009] [Citation(s) in RCA: 193] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Nina Gunde-Cimerman
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia
| | - Ana Plemenitaš
- Institute of Biochemistry, Medical Faculty, University of Ljubljana, Vrazov trg 1, SI-1000 Ljubljana, Slovenia
| | - Aharon Oren
- Department of Plant and Environmental Sciences, The Institute of Life Sciences, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem 9190401, Israel
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12
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Williams TJ, Allen M, Tschitschko B, Cavicchioli R. Glycerol metabolism of haloarchaea. Environ Microbiol 2016; 19:864-877. [PMID: 27768817 DOI: 10.1111/1462-2920.13580] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Haloarchaea are heterotrophic members of the Archaea that thrive in hypersaline environments, often feeding off the glycerol that is produced as an osmolyte by eucaryotic Dunaliella during primary production. In this study we analyzed glycerol metabolism genes in closed genomes of haloarchaea and examined published data describing the growth properties of haloarchaea and experimental data for the enzymes involved. By integrating the genomic data with knowledge from the literature, we derived an understanding of the ecophysiology and evolutionary properties of glycerol catabolic pathways in haloarchaea.
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Affiliation(s)
- Timothy J Williams
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, 2052, New South Wales, Australia
| | - Michelle Allen
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, 2052, New South Wales, Australia
| | - Bernhard Tschitschko
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, 2052, New South Wales, Australia
| | - Ricardo Cavicchioli
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, 2052, New South Wales, Australia
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Calegari-Santos R, Diogo RA, Fontana JD, Bonfim TMB. Carotenoid Production by Halophilic Archaea Under Different Culture Conditions. Curr Microbiol 2016; 72:641-51. [PMID: 26750123 DOI: 10.1007/s00284-015-0974-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 11/22/2015] [Indexed: 12/16/2022]
Abstract
Carotenoids are pigments that may be used as colorants and antioxidants in food, pharmaceutical, and cosmetic industries. Since they also benefit human health, great efforts have been undertaken to search for natural sources of carotenoids, including microbial ones. The optimization of culture conditions to increase carotenoid yield is one of the strategies used to minimize the high cost of carotenoid production by microorganisms. Halophilic archaea are capable of producing carotenoids according to culture conditions. Their main carotenoid is bacterioruberin with 50 carbon atoms. In fact, the carotenoid has important biological functions since it acts as cell membrane reinforcement and it protects the microorganism against DNA damaging agents. Moreover, carotenoid extracts from halophilic archaea have shown high antioxidant capacity. Therefore, current review summarizes the effect of different culture conditions such as salt and carbon source concentrations in the medium, light incidence, and oxygen tension on carotenoid production by halophilic archaea and the strategies such as optimization methodology and two-stage cultivation already used to increase the carotenoid yield of these microorganisms.
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Affiliation(s)
- Rossana Calegari-Santos
- Department of Pharmacy, Enzymology and Fermentation Technology Laboratory, Federal University of Paraná, Av. Pref. Lothário Meissner, 632, Curitiba, Paraná, 80210-170, Brazil
| | - Ricardo Alexandre Diogo
- Polytechnic School, Control and Automation Engineering, Pontifical Catholic University of Paraná, Rua Imaculada Conceição, 1155, Curitiba, Paraná, 80215-901, Brazil
| | - José Domingos Fontana
- Department of Chemistry and Biology, Federal Technological University of Paraná, Rua Deputado Heitor Alencar Furtado, 5000, Curitiba, Paraná, 81280-340, Brazil
| | - Tania Maria Bordin Bonfim
- Department of Pharmacy, Enzymology and Fermentation Technology Laboratory, Federal University of Paraná, Av. Pref. Lothário Meissner, 632, Curitiba, Paraná, 80210-170, Brazil.
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14
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Oren A. Life in Hypersaline Environments. THEIR WORLD: A DIVERSITY OF MICROBIAL ENVIRONMENTS 2016. [DOI: 10.1007/978-3-319-28071-4_8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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15
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Untapped Resources: Biotechnological Potential of Peptides and Secondary Metabolites in Archaea. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2015; 2015:282035. [PMID: 26504428 PMCID: PMC4609331 DOI: 10.1155/2015/282035] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 07/07/2015] [Accepted: 07/08/2015] [Indexed: 11/17/2022]
Abstract
Archaea are an understudied domain of life often found in “extreme” environments in terms of temperature, salinity, and a range of other factors. Archaeal proteins, such as a wide range of enzymes, have adapted to function under these extreme conditions, providing biotechnology with interesting activities to exploit. In addition to producing structural and enzymatic proteins, archaea also produce a range of small peptide molecules (such as archaeocins) and other novel secondary metabolites such as those putatively involved in cell communication (acyl homoserine lactones), which can be exploited for biotechnological purposes. Due to the wide array of metabolites produced there is a great deal of biotechnological potential from antimicrobials such as diketopiperazines and archaeocins, as well as roles in the cosmetics and food industry. In this review we will discuss the diversity of small molecules, both peptide and nonpeptide, produced by archaea and their potential biotechnological applications.
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Rodrigo-Baños M, Garbayo I, Vílchez C, Bonete MJ, Martínez-Espinosa RM. Carotenoids from Haloarchaea and Their Potential in Biotechnology. Mar Drugs 2015; 13:5508-32. [PMID: 26308012 PMCID: PMC4584337 DOI: 10.3390/md13095508] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Revised: 08/02/2015] [Accepted: 08/10/2015] [Indexed: 12/02/2022] Open
Abstract
The production of pigments by halophilic archaea has been analysed during the last half a century. The main reasons that sustains this research are: (i) many haloarchaeal species possess high carotenoids production availability; (ii) downstream processes related to carotenoid isolation from haloarchaea is relatively quick, easy and cheap; (iii) carotenoids production by haloarchaea can be improved by genetic modification or even by modifying several cultivation aspects such as nutrition, growth pH, temperature, etc.; (iv) carotenoids are needed to support plant and animal life and human well-being; and (v) carotenoids are compounds highly demanded by pharmaceutical, cosmetic and food markets. Several studies about carotenoid production by haloarchaea have been reported so far, most of them focused on pigments isolation or carotenoids production under different culture conditions. However, the understanding of carotenoid metabolism, regulation, and roles of carotenoid derivatives in this group of extreme microorganisms remains mostly unrevealed. The uses of those haloarchaeal pigments have also been poorly explored. This work summarises what has been described so far about carotenoids production by haloarchaea and their potential uses in biotechnology and biomedicine. In particular, new scientific evidence of improved carotenoid production by one of the better known haloarchaeon (Haloferax mediterranei) is also discussed.
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Affiliation(s)
- Montserrat Rodrigo-Baños
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
| | - Inés Garbayo
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - Carlos Vílchez
- Algal Biotechnology Group, University of Huelva and Marine International Campus of Excellence (CEIMAR), CIDERTA and Faculty of Sciences, 21071 Huelva, Spain.
| | - María José Bonete
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
| | - Rosa María Martínez-Espinosa
- Biochemistry and Molecular Biology Division, Agrochemistry and Biochemistry Department, Faculty of Sciences, University of Alicante, Ap. 99, E-03080 Alicante, Spain.
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Patterns and determinants of halophilic archaea (class halobacteria) diversity in tunisian endorheic salt lakes and sebkhet systems. Appl Environ Microbiol 2015; 81:4432-41. [PMID: 25911472 DOI: 10.1128/aem.01097-15] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 04/17/2015] [Indexed: 12/13/2022] Open
Abstract
We examined the diversity and community structure of members of the halophilic Archaea (class Halobacteria) in samples from central and southern Tunisian endorheic salt lakes and sebkhet (also known as sebkha) systems using targeted 16S rRNA gene diversity survey and quantitative PCR (qPCR) approaches. Twenty-three different samples from four distinct locations exhibiting a wide range of salinities (2% to 37%) and physical characteristics (water, salt crust, sediment, and biofilm) were examined. A total of 4,759 operational taxonomic units at the 0.03 (species-level) cutoff (OTU0.03s) belonging to 45 currently recognized genera were identified, with 8 to 43 genera (average, 30) identified per sample. In spite of the large number of genera detected per sample, only a limited number (i.e., 2 to 16) usually constituted the majority (≥80%) of encountered sequences. Halobacteria diversity showed a strong negative correlation to salinity (Pearson correlation coefficient = -0.92), and community structure analysis identified salinity, rather than the location or physical characteristics of the sample, as the most important factor shaping the Halobacteria community structure. The relative abundance of genera capable of biosynthesis of the compatible solute(s) trehalose or 2-sulfotrehalose decreased with increasing salinities (Pearson correlation coefficient = -0.80). Indeed, qPCR analysis demonstrated that the Halobacteria otsB (trehalose-6-phosphatase)/16S rRNA gene ratio decreases with increasing salinities (Pearson correlation coefficient = -0.87). The results highlight patterns and determinants of Halobacteria diversity at a previously unexplored ecosystem and indicate that genera lacking trehalose biosynthetic capabilities are more adapted to growth in and colonization of hypersaline (>25% salt) ecosystems than trehalose producers.
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General Characteristics and Important Model Organisms. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2014. [DOI: 10.1128/9781555815516.ch2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Papan C, Penkov S, Herzog R, Thiele C, Kurzchalia T, Shevchenko A. Systematic screening for novel lipids by shotgun lipidomics. Anal Chem 2014; 86:2703-10. [PMID: 24471557 DOI: 10.1021/ac404083u] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
A commonly accepted LIPID MAPS classification recognizes eight major lipid categories and over 550 classes, while new lipid classes are still being discovered by targeted biochemical approaches. Despite their compositional diversity, complex lipids such as glycerolipids, glycerophospholipids, saccharolipids, etc. are constructed from unique structural moieties, e.g., glycerol, fatty acids, choline, phosphate, and trehalose, that are linked by amide, ether, ester, or glycosidic bonds. This modular organization is also reflected in their MS/MS fragmentation pathways, such that common building blocks in different lipid classes tend to generate common fragments. We take advantage of this stereotyped fragmentation to systematically screen for new lipids sharing distant structural similarity to known lipid classes and have developed a discovery approach based on the computational querying of shotgun mass spectra by LipidXplorer software. We applied this concept for screening lipid extracts of C. elegans larvae at the dauer and L3 stages that represent alternative developmental programs executed in response to environmental challenges. The search, covering more than 1.5 million putative chemical compositions, identified a novel class of lyso-maradolipids specifically enriched in dauer larvae.
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Affiliation(s)
- Cyrus Papan
- Max Planck Institute for Cell Biology and Genetics , Pfotenhauerstraße 108, 01307 Dresden, Germany
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Youssef NH, Savage-Ashlock KN, McCully AL, Luedtke B, Shaw EI, Hoff WD, Elshahed MS. Trehalose/2-sulfotrehalose biosynthesis and glycine-betaine uptake are widely spread mechanisms for osmoadaptation in the Halobacteriales. ISME JOURNAL 2013; 8:636-649. [PMID: 24048226 DOI: 10.1038/ismej.2013.165] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 08/16/2013] [Accepted: 08/21/2013] [Indexed: 11/09/2022]
Abstract
We investigated the mechanisms of osmoadaptation in the order Halobacteriales, with special emphasis on Haladaptatus paucihalophilus, known for its ability to survive in low salinities. H. paucihalophilus genome contained genes for trehalose synthesis (trehalose-6-phosphate synthase/trehalose-6-phosphatase (OtsAB pathway) and trehalose glycosyl-transferring synthase pathway), as well as for glycine betaine uptake (BCCT family of secondary transporters and QAT family of ABC transporters). H. paucihalophilus cells synthesized and accumulated ∼1.97-3.72 μmol per mg protein of trehalose in a defined medium, with its levels decreasing with increasing salinities. When exogenously supplied, glycine betaine accumulated intracellularly with its levels increasing at higher salinities. RT-PCR analysis strongly suggested that H. paucihalophilus utilizes the OtsAB pathway for trehalose synthesis. Out of 83 Halobacteriales genomes publicly available, genes encoding the OtsAB pathway and glycine betaine BCCT family transporters were identified in 38 and 60 genomes, respectively. Trehalose (or its sulfonated derivative) production and glycine betaine uptake, or lack thereof, were experimentally verified in 17 different Halobacteriales species. Phylogenetic analysis suggested that trehalose synthesis is an ancestral trait within the Halobacteriales, with its absence in specific lineages reflecting the occurrence of gene loss events during Halobacteriales evolution. Analysis of multiple culture-independent survey data sets demonstrated the preference of trehalose-producing genera to saline and low salinity habitats, and the dominance of genera lacking trehalose production capabilities in permanently hypersaline habitats. This study demonstrates that, contrary to current assumptions, compatible solutes production and uptake represent a common mechanism of osmoadaptation within the Halobacteriales.
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Affiliation(s)
- Noha H Youssef
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Kristen N Savage-Ashlock
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA.,3Present address: Department of Biology, Georgia State University, Atlanta, Georgia
| | - Alexandra L McCully
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA.,4Present address: Department of Biology, Indiana University, Bloomington IN
| | - Brandon Luedtke
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA.,5Present address: US Department of Agriculture, Agricultural Research Service, Roman L. Hruska Meat Animal Research Center, Clay Center, NE 68933-0166
| | - Edward I Shaw
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA
| | - Wouter D Hoff
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA.,Department of Chemistry, Oklahoma State University, Stillwater, OK, USA
| | - Mostafa S Elshahed
- Department of Microbiology and Molecular Genetics, Oklahoma State University, Stillwater, OK, USA.
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Paritala H, Carroll KS. New targets and inhibitors of mycobacterial sulfur metabolism. Infect Disord Drug Targets 2013; 13:85-115. [PMID: 23808874 PMCID: PMC4332622 DOI: 10.2174/18715265113139990022] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 05/08/2013] [Indexed: 11/22/2022]
Abstract
The identification of new antibacterial targets is urgently needed to address multidrug resistant and latent tuberculosis infection. Sulfur metabolic pathways are essential for survival and the expression of virulence in many pathogenic bacteria, including Mycobacterium tuberculosis. In addition, microbial sulfur metabolic pathways are largely absent in humans and therefore, represent unique targets for therapeutic intervention. In this review, we summarize our current understanding of the enzymes associated with the production of sulfated and reduced sulfur-containing metabolites in Mycobacteria. Small molecule inhibitors of these catalysts represent valuable chemical tools that can be used to investigate the role of sulfur metabolism throughout the Mycobacterial lifecycle and may also represent new leads for drug development. In this light, we also summarize recent progress made in the development of inhibitors of sulfur metabolism enzymes.
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Affiliation(s)
| | - Kate S. Carroll
- Department of Chemistry, The Scripps Research Institute, Jupiter, Florida, 33458, USA
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Siddaramappa S, Challacombe JF, DeCastro RE, Pfeiffer F, Sastre DE, Giménez MI, Paggi RA, Detter JC, Davenport KW, Goodwin LA, Kyrpides N, Tapia R, Pitluck S, Lucas S, Woyke T, Maupin-Furlow JA. A comparative genomics perspective on the genetic content of the alkaliphilic haloarchaeon Natrialba magadii ATCC 43099T. BMC Genomics 2012; 13:165. [PMID: 22559199 PMCID: PMC3403918 DOI: 10.1186/1471-2164-13-165] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 05/04/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Natrialba magadii is an aerobic chemoorganotrophic member of the Euryarchaeota and is a dual extremophile requiring alkaline conditions and hypersalinity for optimal growth. The genome sequence of Nab. magadii type strain ATCC 43099 was deciphered to obtain a comprehensive insight into the genetic content of this haloarchaeon and to understand the basis of some of the cellular functions necessary for its survival. RESULTS The genome of Nab. magadii consists of four replicons with a total sequence of 4,443,643 bp and encodes 4,212 putative proteins, some of which contain peptide repeats of various lengths. Comparative genome analyses facilitated the identification of genes encoding putative proteins involved in adaptation to hypersalinity, stress response, glycosylation, and polysaccharide biosynthesis. A proton-driven ATP synthase and a variety of putative cytochromes and other proteins supporting aerobic respiration and electron transfer were encoded by one or more of Nab. magadii replicons. The genome encodes a number of putative proteases/peptidases as well as protein secretion functions. Genes encoding putative transcriptional regulators, basal transcription factors, signal perception/transduction proteins, and chemotaxis/phototaxis proteins were abundant in the genome. Pathways for the biosynthesis of thiamine, riboflavin, heme, cobalamin, coenzyme F420 and other essential co-factors were deduced by in depth sequence analyses. However, approximately 36% of Nab. magadii protein coding genes could not be assigned a function based on Blast analysis and have been annotated as encoding hypothetical or conserved hypothetical proteins. Furthermore, despite extensive comparative genomic analyses, genes necessary for survival in alkaline conditions could not be identified in Nab. magadii. CONCLUSIONS Based on genomic analyses, Nab. magadii is predicted to be metabolically versatile and it could use different carbon and energy sources to sustain growth. Nab. magadii has the genetic potential to adapt to its milieu by intracellular accumulation of inorganic cations and/or neutral organic compounds. The identification of Nab. magadii genes involved in coenzyme biosynthesis is a necessary step toward further reconstruction of the metabolic pathways in halophilic archaea and other extremophiles. The knowledge gained from the genome sequence of this haloalkaliphilic archaeon is highly valuable in advancing the applications of extremophiles and their enzymes.
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Affiliation(s)
| | - Jean F Challacombe
- DOE Joint Genome Institute, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Rosana E DeCastro
- Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3250 4to Nivel, Mar del Plata, 7600, Argentina
| | - Friedhelm Pfeiffer
- Department of Membrane Biochemistry, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152, Martinsried, Germany
| | - Diego E Sastre
- Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3250 4to Nivel, Mar del Plata, 7600, Argentina
| | - María I Giménez
- Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3250 4to Nivel, Mar del Plata, 7600, Argentina
| | - Roberto A Paggi
- Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de Mar del Plata, Funes 3250 4to Nivel, Mar del Plata, 7600, Argentina
| | - John C Detter
- DOE Joint Genome Institute, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Karen W Davenport
- DOE Joint Genome Institute, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Lynne A Goodwin
- DOE Joint Genome Institute, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Nikos Kyrpides
- DOE Joint Genome Institute, Walnut Creek, CA, 94598, USA
| | - Roxanne Tapia
- DOE Joint Genome Institute, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Samuel Pitluck
- DOE Joint Genome Institute, Walnut Creek, CA, 94598, USA
| | - Susan Lucas
- DOE Joint Genome Institute, Walnut Creek, CA, 94598, USA
| | - Tanja Woyke
- DOE Joint Genome Institute, Walnut Creek, CA, 94598, USA
| | - Julie A Maupin-Furlow
- Department of Microbiology and Cell Science, University of Florida, Bldg. 981, Museum Rd., P.O. Box 110700, Gainesville, FL, 32611-0700, USA
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Abrevaya XC, Paulino-Lima IG, Galante D, Rodrigues F, Mauas PJD, Cortón E, Lage CDAS. Comparative survival analysis of Deinococcus radiodurans and the haloarchaea Natrialba magadii and Haloferax volcanii exposed to vacuum ultraviolet irradiation. ASTROBIOLOGY 2011; 11:1034-1040. [PMID: 22165956 DOI: 10.1089/ast.2011.0607] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The haloarchaea Natrialba magadii and Haloferax volcanii, as well as the radiation-resistant bacterium Deinococcus radiodurans, were exposed to vacuum UV (VUV) radiation at the Brazilian Synchrotron Light Laboratory. Cell monolayers (containing 10(5) to 10(6) cells per sample) were prepared over polycarbonate filters and irradiated under high vacuum (10(-5) Pa) with polychromatic synchrotron radiation. N. magadii was remarkably resistant to high vacuum with a survival fraction of (3.77±0.76)×10(-2), which was larger than that of D. radiodurans (1.13±0.23)×10(-2). The survival fraction of the haloarchaea H. volcanii, of (3.60±1.80)×10(-4), was much smaller. Radiation resistance profiles were similar between the haloarchaea and D. radiodurans for fluences up to 150 J m(-2). For fluences larger than 150 J m(-2), there was a significant decrease in the survival of haloarchaea, and in particular H. volcanii did not survive. Survival for D. radiodurans was 1% after exposure to the higher VUV fluence (1350 J m(-2)), while N. magadii had a survival lower than 0.1%. Such survival fractions are discussed regarding the possibility of interplanetary transfer of viable microorganisms and the possible existence of microbial life in extraterrestrial salty environments such as the planet Mars and Jupiter's moon Europa. This is the first work to report survival of haloarchaea under simulated interplanetary conditions.
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Affiliation(s)
- Ximena C Abrevaya
- Instituto de Astronomía y Física del Espacio (IAFE), Universidad de Buenos Aires and CONICET, Buenos Aires, Argentina.
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Goh F, Jeon YJ, Barrow K, Neilan BA, Burns BP. Osmoadaptive strategies of the archaeon Halococcus hamelinensis isolated from a hypersaline stromatolite environment. ASTROBIOLOGY 2011; 11:529-536. [PMID: 21810017 DOI: 10.1089/ast.2010.0591] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Biogenic stromatolites are sources of significant information on the evolution of microbial life. Despite their evolutionary significance, little is known about the mechanisms of osmoadaptation by microorganisms that comprise living stromatolites thriving in hypersaline environments. Osmoadaptive strategies for Halococcus hamelinensis, a novel halophilic archaeon recently isolated from living stromatolites in the hypersaline reaches of Shark Bay, were thus a particular interest in this study. To investigate the possibility of "salt-in-cytoplasm"-associated osmoadaptation for this archaeon, flame photometry studies were performed. From the results, it was evident that this halophilic archaeon did not accumulate intracellular K(+) ions when cells were exposed to either osmotic shock or conditions with gradual increments in salinity. These results were further supported by polymerase chain reaction (PCR) analyses where there was no evidence for the existence of homologous genes to an ATP-driven, high-affinity potassium uptake system in Halococcus hamelinensis. To identify an alternative salt adaptation mechanism associated with accumulation of compatible solutes for this archaeon, (1)H nuclear magnetic resonance (NMR) spectroscopy experiments were carried out. Results indicate that glycine betaine, trehalose, and glutamate are solutes likely to be involved in osmoregulation in this archeaon. Subsequent (1)H NMR analysis of cell extracts from this microorganism grown under various NaCl concentrations revealed that intracellular levels of glycine betaine increased with increasing concentrations of NaCl. This behavior of increasing glycine betaine concentration with increasing external NaCl is consistent with its identity as an osmolyte. In contrast, intracellular levels of trehalose were decreased in high concentrations of NaCl. This provides evidence that compatible solute accumulation appears to be the preferential salt regulation mechanism for this haloarchaeon, in contrast to the salt-in-cytoplasm strategy employed by many other halophilic archaea.
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Affiliation(s)
- Falicia Goh
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, Australia
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Genome sequence of Halorhabdus tiamatea, the first archaeon isolated from a deep-sea anoxic brine lake. J Bacteriol 2011; 193:4553-4. [PMID: 21705593 DOI: 10.1128/jb.05462-11] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We present the draft genome of Halorhabdus tiamatea, the first member of the Archaea ever isolated from a deep-sea anoxic brine. Genome comparison with Halorhabdus utahensis revealed some striking differences, including a marked increase in genes associated with transmembrane transport and putative genes for a trehalose synthase and a lactate dehydrogenase.
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Characterization of growth and metabolism of the haloalkaliphile Natronomonas pharaonis. PLoS Comput Biol 2010; 6:e1000799. [PMID: 20543878 PMCID: PMC2881530 DOI: 10.1371/journal.pcbi.1000799] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Accepted: 04/28/2010] [Indexed: 12/03/2022] Open
Abstract
Natronomonas pharaonis is an archaeon adapted to two extreme conditions: high salt concentration and alkaline pH. It has become one of the model organisms for the study of extremophilic life. Here, we present a genome-scale, manually curated metabolic reconstruction for the microorganism. The reconstruction itself represents a knowledge base of the haloalkaliphile's metabolism and, as such, would greatly assist further investigations on archaeal pathways. In addition, we experimentally determined several parameters relevant to growth, including a characterization of the biomass composition and a quantification of carbon and oxygen consumption. Using the metabolic reconstruction and the experimental data, we formulated a constraints-based model which we used to analyze the behavior of the archaeon when grown on a single carbon source. Results of the analysis include the finding that Natronomonas pharaonis, when grown aerobically on acetate, uses a carbon to oxygen consumption ratio that is theoretically near-optimal with respect to growth and energy production. This supports the hypothesis that, under simple conditions, the microorganism optimizes its metabolism with respect to the two objectives. We also found that the archaeon has a very low carbon efficiency of only about 35%. This inefficiency is probably due to a very low P/O ratio as well as to the other difficulties posed by its extreme environment. Extremophiles are organisms that thrive in physically or geochemically extreme conditions that are detrimental, even lethal, to the majority of life on Earth. Natronomonas pharaonis is one that has been able to adapt to both high salt concentration and an alkaline pH. In this study, we investigate the chemical reactions that occur within the microorganism, collectively referred to as its metabolic network, that allow it to convert the nutrients in its environment to biomass and energy. Specifically, we reconstructed the network by collecting evidence for the existence of reactions from the literature, and then supplemented them with computational approaches, for example by searching the genome of Natronomonas pharaonis for genes that could potentially encode analogs of known enzymes from other organisms. Finally, with the network in hand, we developed a computational model which we used to simulate growth. Among other results, we found indications that Natronomonas pharaonis regulates its metabolism such that energy production and growth are maximized. Despite this however, we also found that Natronomonas pharaonis is only able to incorporate a very small fraction of the total carbon that it consumes (approximately 35%), likely in no small part due to the difficulties posed by its environment.
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Schwaiger R, Schwarz C, Furtwängler K, Tarasov V, Wende A, Oesterhelt D. Transcriptional control by two leucine-responsive regulatory proteins in Halobacterium salinarum R1. BMC Mol Biol 2010; 11:40. [PMID: 20509863 PMCID: PMC2894021 DOI: 10.1186/1471-2199-11-40] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2010] [Accepted: 05/28/2010] [Indexed: 12/26/2022] Open
Abstract
Background Archaea combine bacterial-as well as eukaryotic-like features to regulate cellular processes. Halobacterium salinarum R1 encodes eight leucine-responsive regulatory protein (Lrp)-homologues. The function of two of them, Irp (OE3923F) and lrpA1 (OE2621R), were analyzed by gene deletion and overexpression, including genome scale impacts using microarrays. Results It was shown that Lrp affects the transcription of multiple target genes, including those encoding enzymes involved in amino acid synthesis, central metabolism, transport processes and other regulators of transcription. In contrast, LrpA1 regulates transcription in a more specific manner. The aspB3 gene, coding for an aspartate transaminase, was repressed by LrpA1 in the presence of L-aspartate. Analytical DNA-affinity chromatography was adapted to high salt, and demonstrated binding of LrpA1 to its own promoter, as well as L-aspartate dependent binding to the aspB3 promoter. Conclusion The gene expression profiles of two archaeal Lrp-homologues report in detail their role in H. salinarum R1. LrpA1 and Lrp show similar functions to those already described in bacteria, but in addition they play a key role in regulatory networks, such as controlling the transcription of other regulators. In a more detailed analysis ligand dependent binding of LrpA1 was demonstrated to its target gene aspB3.
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Affiliation(s)
- Rita Schwaiger
- Max Planck Institute of Biochemistry, Department of Membrane Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
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Synthesis and production of polyhydroxyalkanoates by halophiles: current potential and future prospects. Appl Microbiol Biotechnol 2009; 85:1687-96. [DOI: 10.1007/s00253-009-2397-6] [Citation(s) in RCA: 157] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 11/30/2009] [Accepted: 12/01/2009] [Indexed: 10/20/2022]
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Abstract
In order to survive extremes of pH, temperature, salinity and pressure, organisms have been found to develop unique defences against their environment, leading to the biosynthesis of novel molecules ranging from simple osmolytes and lipids to complex secondary metabolites. This review highlights novel molecules isolated from microorganisms that either tolerate or favour extreme growth conditions.
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Affiliation(s)
- Zoe E Wilson
- Department of Chemistry, University of Auckland, 23 Symonds St, Auckland, 1010, New Zealand
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Loft KJ, Bojarová P, Slámová K, Kren V, Williams SJ. Synthesis of sulfated glucosaminides for profiling substrate specificities of sulfatases and fungal beta-N-acetylhexosaminidases. Chembiochem 2009; 10:565-76. [PMID: 19156788 DOI: 10.1002/cbic.200800656] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Systematic sulfation: Sulfated glycoconjugates are degraded either by desulfation followed by glycoside cleavage, or by glycoside cleavage followed by desulfation. To study these processes, here we report the synthesis of four regioisomerically sulfated p-nitrophenyl glucosaminides from the common precursor p-nitrophenyl N-acetyl-beta-D-glucosaminide. These substrates allowed the rapid analysis of the substrate preferences of a set of four sulfatases and 24 hexosaminidases.Sulfated carbohydrates are components of many glycoconjugates, and are degraded by two major processes: cleavage of the sulfate ester by a sulfatase, or en bloc removal of a sulfated monosaccharide by a glycoside hydrolase. However, these processes have proved difficult to study owing to a lack of homogeneous, defined substrates. We describe here the synthesis of a series of p-nitrophenyl beta-D-glucosaminides bearing sulfate esters at the 2-, 3-, 4- or 6-positions, by divergent routes starting with p-nitrophenyl 2-acetamido-2-deoxy-beta-D-glucopyranoside. The sulfated p-nitrophenyl beta-D-glucosaminides were used to study the substrate specificity of four sulfatases (from Helix pomatia, Patella vulgata, abalone, and Pseudomonas aeruginosa), and revealed significant differences in the preference of each of these enzymes for desulfation at different positions around the sugar ring. The 3-, 4- and 6-sulfated p-nitrophenyl 2-acetamido-2-deoxy-beta-D-glucosaminides were screened against a panel of 24 fungal beta-N-acetylhexosaminidases to assess their substrate specificity. While the 4- and 6-sulfates were substrates for many of the fungal enzymes investigated, only a single beta-N-acetylhexosaminidase, that from Penicillium chrysogenum, could hydrolyze the 3-sulfated p-nitrophenyl glycoside. Together these results demonstrate the utility of sulfated p-nitrophenyl beta-D-glucosaminides for the study of both sulfatases and glycoside hydrolases.
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Affiliation(s)
- Karen J Loft
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, Victoria, Australia
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Saum SH, Müller V. Regulation of osmoadaptation in the moderate halophile Halobacillus halophilus: chloride, glutamate and switching osmolyte strategies. SALINE SYSTEMS 2008; 4:4. [PMID: 18442383 PMCID: PMC2412884 DOI: 10.1186/1746-1448-4-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2008] [Accepted: 04/28/2008] [Indexed: 11/10/2022]
Abstract
The moderate halophile Halobacillus halophilus is the paradigm for chloride dependent growth in prokaryotes. Recent experiments shed light on the molecular basis of the chloride dependence that is reviewed here. In the presence of moderate salinities Halobacillus halophilus mainly accumulates glutamine and glutamate to adjust turgor. The transcription of glnA2 (encoding a glutamine synthetase) as well as the glutamine synthetase activity were identified as chloride dependent steps. Halobacillus halophilus switches its osmolyte strategy and produces proline as the main compatible solute at high salinities. Furthermore, Halobacillus halophilus also shifts its osmolyte strategy at the transition from the exponential to the stationary phase where proline is exchanged by ectoine. Glutamate was found as a "second messenger" essential for proline production. This observation leads to a new model of sensing salinity by sensing the physico-chemical properties of different anions.
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Affiliation(s)
- Stephan H Saum
- Molecular Microbiology & Bioenergetics, Institute of Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany.
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Oren A. Microbial life at high salt concentrations: phylogenetic and metabolic diversity. SALINE SYSTEMS 2008; 4:2. [PMID: 18412960 PMCID: PMC2329653 DOI: 10.1186/1746-1448-4-2] [Citation(s) in RCA: 459] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Accepted: 04/15/2008] [Indexed: 12/04/2022]
Abstract
Halophiles are found in all three domains of life. Within the Bacteria we know halophiles within the phyla Cyanobacteria, Proteobacteria, Firmicutes, Actinobacteria, Spirochaetes, and Bacteroidetes. Within the Archaea the most salt-requiring microorganisms are found in the class Halobacteria. Halobacterium and most of its relatives require over 100–150 g/l salt for growth and structural stability. Also within the order Methanococci we encounter halophilic species. Halophiles and non-halophilic relatives are often found together in the phylogenetic tree, and many genera, families and orders have representatives with greatly different salt requirement and tolerance. A few phylogenetically coherent groups consist of halophiles only: the order Halobacteriales, family Halobacteriaceae (Euryarchaeota) and the anaerobic fermentative bacteria of the order Halanaerobiales (Firmicutes). The family Halomonadaceae (Gammaproteobacteria) almost exclusively contains halophiles. Halophilic microorganisms use two strategies to balance their cytoplasm osmotically with their medium. The first involves accumulation of molar concentrations of KCl. This strategy requires adaptation of the intracellular enzymatic machinery, as proteins should maintain their proper conformation and activity at near-saturating salt concentrations. The proteome of such organisms is highly acidic, and most proteins denature when suspended in low salt. Such microorganisms generally cannot survive in low salt media. The second strategy is to exclude salt from the cytoplasm and to synthesize and/or accumulate organic 'compatible' solutes that do not interfere with enzymatic activity. Few adaptations of the cells' proteome are needed, and organisms using the 'organic-solutes-in strategy' often adapt to a surprisingly broad salt concentration range. Most halophilic Bacteria, but also the halophilic methanogenic Archaea use such organic solutes. A variety of such solutes are known, including glycine betaine, ectoine and other amino acid derivatives, sugars and sugar alcohols. The 'high-salt-in strategy' is not limited to the Halobacteriaceae. The Halanaerobiales (Firmicutes) also accumulate salt rather than organic solutes. A third, phylogenetically unrelated organism accumulates KCl: the red extremely halophilic Salinibacter (Bacteroidetes), recently isolated from saltern crystallizer brines. Analysis of its genome showed many points of resemblance with the Halobacteriaceae, probably resulting from extensive horizontal gene transfer. The case of Salinibacter shows that more unusual types of halophiles may be waiting to be discovered.
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Affiliation(s)
- Aharon Oren
- Department of Plant and Environmental Sciences, Hebrew University of Jerusalem, Jerusalem, Israel.
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Pandhal J, Wright PC, Biggs CA. Proteomics with a pinch of salt: a cyanobacterial perspective. SALINE SYSTEMS 2008; 4:1. [PMID: 18412952 PMCID: PMC2386806 DOI: 10.1186/1746-1448-4-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/15/2008] [Accepted: 04/15/2008] [Indexed: 11/10/2022]
Abstract
Cyanobacteria are ancient life forms and have adapted to a variety of extreme environments, including high salinity. Biochemical, physiological and genetic studies have contributed to uncovering their underlying survival mechanisms, and as recent studies demonstrate, proteomics has the potential to increase our overall understanding further. To date, most salt-related cyanobacterial proteomic studies have utilised gel electrophoresis with the model organism Synechocystis sp. PCC6803. Moreover, focus has been on 2-4% w/v NaCl concentrations within different cellular compartments. Under these conditions, Synechocystis sp. PCC6803 was found to respond and adapt to salt stress through synthesis of general and specific stress proteins, altering the protein composition of extracellular layers, and re-directing control of complex central intermediary pathways. Post-transcriptional control was also predicted through non-correlating transcript level data and identification of protein isoforms.In this paper, we also review technical developments with emphasis on improving the quality and quantity of proteomic data and overcoming the detrimental effects of salt on sample preparation and analysis. Developments in gel-free methods include protein and peptide fractionation workflows, which can increase coverage of the proteome (20% in Synechocystis sp. PCC6803). Quantitative techniques have also improved in accuracy, resulting in confidence in quantitation approaching or even surpassing that seen in transcriptomic techniques (better than 1.5-fold in differential expression). Furthermore, in vivo metabolic labelling and de novo protein sequencing software have improved the ability to apply proteomics to unsequenced environmental isolates. The example used in this review is a cyanobacterium isolated from a Saharan salt lake.
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Affiliation(s)
- Jagroop Pandhal
- Biological and Environmental Systems Group, Department of Chemical and Process Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK
| | - Phillip C Wright
- Biological and Environmental Systems Group, Department of Chemical and Process Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK
| | - Catherine A Biggs
- Biological and Environmental Systems Group, Department of Chemical and Process Engineering, The University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK
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Abstract
In spite of their common hypersaline environment, halophilic archaea are surprisingly different in their nutritional demands and metabolic pathways. The metabolic diversity of halophilic archaea was investigated at the genomic level through systematic metabolic reconstruction and comparative analysis of four completely sequenced species: Halobacterium salinarum, Haloarcula marismortui, Haloquadratum walsbyi, and the haloalkaliphile Natronomonas pharaonis. The comparative study reveals different sets of enzyme genes amongst halophilic archaea, e.g. in glycerol degradation, pentose metabolism, and folate synthesis. The carefully assessed metabolic data represent a reliable resource for future system biology approaches as it also links to current experimental data on (halo)archaea from the literature.
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Valenzuela-Encinas C, Neria-González I, Alcántara-Hernández RJ, Enríquez-Aragón JA, Estrada-Alvarado I, Hernández-Rodríguez C, Dendooven L, Marsch R. Phylogenetic analysis of the archaeal community in an alkaline-saline soil of the former lake Texcoco (Mexico). Extremophiles 2007; 12:247-54. [DOI: 10.1007/s00792-007-0121-y] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2007] [Accepted: 10/29/2007] [Indexed: 11/30/2022]
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Abstract
Pathogenic bacteria have developed numerous mechanisms to survive inside a hostile host environment. The human pathogen Mycobacterium tuberculosis (M. tb) is thought to control the human immune response with diverse biomolecules, including a variety of exotic lipids. One prevalent M. tb-specific sulfated metabolite, termed sulfolipid-1 (SL-1), has been correlated with virulence though its specific biological function is not known. Recent advances in our understanding of SL-1 biosynthesis will help elucidate the role of this curious metabolite in M. tb infection. Furthermore, the study of SL-1 has led to questions regarding the significance of sulfation in mycobacteria. Examples of sulfated metabolites as mediators of interactions between bacteria and plants suggest that sulfation is a key modulator of extracellular signaling between prokaryotes and eukaryotes. The discovery of novel sulfated metabolites in M. tb and related mycobacteria strengthens this hypothesis. Finally, mechanistic and structural data from sulfate-assimilation enzymes have revealed how M. tb controls the flux of sulfate in the cell. Mutants with defects in sulfate assimilation indicate that the fate of sulfur in M. tb is a critical survival determinant for the bacteria during infection and suggest novel targets for tuberculosis drug therapy.
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Affiliation(s)
- Michael W Schelle
- Department of Chemistry, University of California Berkeley, CA 94720, USA
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Abstract
The identification of new antibacterial targets is urgently needed to address multidrug resistant and latent tuberculosis infection. Sulfur metabolic pathways are essential for survival and the expression of virulence in many pathogenic bacteria, including Mycobacterium tuberculosis. In addition, microbial sulfur metabolic pathways are largely absent in humans and therefore, represent unique targets for therapeutic intervention. In this review, we summarize our current understanding of the enzymes associated with the production of sulfated and reduced sulfur-containing metabolites in Mycobacteria. Small molecule inhibitors of these catalysts represent valuable chemical tools that can be used to investigate the role of sulfur metabolism throughout the Mycobacterial lifecycle and may also represent new leads for drug development. In this light, we also summarize recent progress in the development of inhibitors of sulfur metabolism enzymes.
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Affiliation(s)
- Devayani P. Bhave
- Chemical Biology Ph.D. Program, University of Michigan, Ann Arbor, Michigan, 48109-2216
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, 48109-2216
| | - Wilson B. Muse
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, 48109-2216
| | - Kate S. Carroll
- Chemical Biology Ph.D. Program, University of Michigan, Ann Arbor, Michigan, 48109-2216
- Life Sciences Institute, University of Michigan, Ann Arbor, Michigan, 48109-2216
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, 48109-2216
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Jorge CD, Lamosa P, Santos H. Alpha-D-mannopyranosyl-(1-->2)-alpha-D-glucopyranosyl-(1-->2)-glycerate in the thermophilic bacterium Petrotoga miotherma--structure, cellular content and function. FEBS J 2007; 274:3120-7. [PMID: 17521333 DOI: 10.1111/j.1742-4658.2007.05844.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The intracellular accumulation of low molecular mass organic compounds in response to stressful conditions was investigated in the thermophilic bacterium Petrotoga miotherma, a member of the order Thermotogales. This led to the discovery of a new solute, whose structure was established as alpha-D-mannopyranosyl-(1-->2)-alpha-D-glucopyranosyl-(1-->2)-glycerate (MGG) by MMR spectroscopy and MS. Under optimum growth conditions (3% NaCl; 55 degrees C), MGG was the major solute [up to 0.6 micromol.(mg protein)(-1)]; alpha-glutamate and proline were also present but in minor amounts [below 0.08 micromol.(mg protein)(-1)]. The level of MGG increased notably with the salinity of the growth medium up to the optimum NaCl concentration. At higher NaCl concentrations, however, the level of MGG decreased, whereas the levels of proline and alpha-glutamate increased about five-fold and 10-fold, respectively. MGG plays a role during low-level osmotic adaptation of Petrotoga miotherma, whereas alpha-glutamate and, to a lesser extent, proline are used for osmoprotection under salt stress. MGG is not part of the cell strategy for coping with heat or oxidative stress. Nevertheless, MGG was an efficient protector of pig heart malate dehydrogenase against heat inactivation and freeze-drying, although mannosylglycerate was better. This is the first report on the occurrence of MGG in living systems.
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Affiliation(s)
- Carla D Jorge
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal
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Neelon K, Schreier HJ, Meekins H, Robinson PM, Roberts MF. Compatible solute effects on thermostability of glutamine synthetase and aspartate transcarbamoylase from Methanococcus jannaschii. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2005; 1753:164-73. [PMID: 16168724 DOI: 10.1016/j.bbapap.2005.08.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2004] [Revised: 08/11/2005] [Accepted: 08/11/2005] [Indexed: 11/23/2022]
Abstract
Methanococcus jannaschii accumulates alpha- and beta-glutamate as osmolytes. The effect of these and other solutes on the thermostability of two multisubunit metabolic enzymes from M. jannaschii, aspartate transcarbamoylase catalytic trimer (ATCase C3) and glutamine synthetase (GS), has been measured and compared to solute effects on bacterial mesophilic counterparts in order to explore if osmolytes accumulated by each organism can preferentially stabilize the proteins to thermal unfolding. For both ATCase enzymes and for the B. subtilis GS, the solutes normally accumulated by the organism were very effective in protecting the enzyme from losing activity at high temperatures, although solute effects on loss of secondary structure did not necessarily correlate with this thermoprotection of activity. The recombinant M. jannaschii GS exhibited quite different behavior. The pure enzyme had a thermal unfolding transition with a midpoint temperature (Tm) less than 60 degrees C, well under the growth temperature of the organism (85 degrees C). None of the small molecule solutes tested (including the K+-glutamate isomers accumulated by M. jannaschii) significantly stabilized the protein to incubation at 85 degrees C. Instead, protein-protein interactions, as illustrated by E. coli GroEL or ribosomal protein L2 stabilization of GS, appeared to be the dominant factor in stabilizing this archaeal enzyme at the growth temperature.
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Affiliation(s)
- Kelly Neelon
- Merkert Chemistry Center, Boston College, Chestnut Hill, MA 02467, USA
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Falb M, Pfeiffer F, Palm P, Rodewald K, Hickmann V, Tittor J, Oesterhelt D. Living with two extremes: conclusions from the genome sequence of Natronomonas pharaonis. Genome Res 2005; 15:1336-43. [PMID: 16169924 PMCID: PMC1240075 DOI: 10.1101/gr.3952905] [Citation(s) in RCA: 173] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Natronomonas pharaonis is an extremely haloalkaliphilic archaeon that was isolated from salt-saturated lakes of pH 11. We sequenced its 2.6-Mb GC-rich chromosome and two plasmids (131 and 23 kb). Genome analysis suggests that it is adapted to cope with severe ammonia and heavy metal deficiencies that arise at high pH values. A high degree of nutritional self-sufficiency was predicted and confirmed by growth in a minimal medium containing leucine but no other amino acids or vitamins. Genes for a complex III analog of the respiratory chain could not be identified in the N. pharaonis genome, but respiration and oxidative phosphorylation were experimentally proven. These studies identified protons as coupling ion between respiratory chain and ATP synthase, in contrast to other alkaliphiles using sodium instead. Secretome analysis predicts many extracellular proteins with alkaline-resistant lipid anchors, which are predominantly exported through the twin-arginine pathway. In addition, a variety of glycosylated cell surface proteins probably form a protective complex cell envelope. N. pharaonis is fully equipped with archaeal signal transduction and motility genes. Several receptors/transducers signaling to the flagellar motor display novel domain architectures. Clusters of signal transduction genes are rearranged in haloarchaeal genomes, whereas those involved in information processing or energy metabolism show a highly conserved gene order.
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Affiliation(s)
- Michaela Falb
- Max-Planck-Institute of Biochemistry, Department of Membrane Biochemistry, D-82152 Martinsried, Germany
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Roberts MF. Organic compatible solutes of halotolerant and halophilic microorganisms. SALINE SYSTEMS 2005; 1:5. [PMID: 16176595 PMCID: PMC1224877 DOI: 10.1186/1746-1448-1-5] [Citation(s) in RCA: 360] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2005] [Accepted: 08/04/2005] [Indexed: 11/10/2022]
Abstract
Microorganisms that adapt to moderate and high salt environments use a variety of solutes, organic and inorganic, to counter external osmotic pressure. The organic solutes can be zwitterionic, noncharged, or anionic (along with an inorganic cation such as K(+)). The range of solutes, their diverse biosynthetic pathways, and physical properties of the solutes that effect molecular stability are reviewed.
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Affiliation(s)
- Mary F Roberts
- Merkert Chemistry Center, Boston College, 2609 Beacon Street, Chestnut Hill, MA 02465, USA.
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Abstract
Two major types of environment provide habitats for the most xerophilic organisms known: foods preserved by some form of dehydration or enhanced sugar levels, and hypersaline sites where water availability is limited by a high concentration of salts (usually NaCl). These environments are essentially microbial habitats, with high-sugar foods being dominated by xerophilic (sometimes called osmophilic) filamentous fungi and yeasts, some of which are capable of growth at a water activity (a(w)) of 0.61, the lowest a(w) value for growth recorded to date. By contrast, high-salt environments are almost exclusively populated by prokaryotes, notably the haloarchaea, capable of growing in saturated NaCl (a(w) 0.75). Different strategies are employed for combating the osmotic stress imposed by high levels of solutes in the environment. Eukaryotes and most prokaryotes synthesize or accumulate organic so-called 'compatible solutes' (osmolytes) that have counterbalancing osmotic potential. A restricted range of bacteria and the haloarchaea counterbalance osmotic stress imposed by NaCl by accumulating equivalent amounts of KCl. Haloarchaea become entrapped and survive for long periods inside halite (NaCl) crystals. They are also found in ancient subterranean halite (NaCl) deposits, leading to speculation about survival over geological time periods.
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Affiliation(s)
- W D Grant
- Department of Infection, Immunity and Inflammation, University of Leicester, Maurice Shock Building, University Road, Leicester LE1 9HN, UK.
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Motta A, Romano I, Gambacorta A. Rapid and sensitive NMR method for osmolyte determination. J Microbiol Methods 2004; 58:289-94. [PMID: 15234528 DOI: 10.1016/j.mimet.2004.04.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2004] [Revised: 03/24/2004] [Accepted: 04/08/2004] [Indexed: 11/16/2022]
Abstract
We propose a rapid and sensitive method for osmolyte determination, based on one-dimensional and two-dimensional 1H NMR spectroscopy applied directly on culture of haloalkalophilic Halomonas pantelleriensis and acidothermophilic archaeon Sulfolobus solfataricus, without any extraction procedure. The osmoprotectants hydroxyectoine, ectoine, glutamate, glycine-betaine and treahalose can easily be quantified by integrating the peak areas with respect to an internal standard, and the concentrations evaluated with this method are in excellent agreement with the values previously reported. Furthermore, trace amount of osmoprotectants, often undetectable after extraction procedures, can also be evaluated.
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Affiliation(s)
- Andrea Motta
- Istituto di Chimica Biomolecolare del CNR, Comprensorio Olivetti, Edificio 70, via Campi, Flegrei 34, Pozzuoli I-80078, Italy.
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Uzawa H, Nishida Y, Sasaki K, Nagatsuka T, Hiramatsu H, Kobayashi K. Sulfatase-catalyzed assembly of regioselectively O-sulfonated p-nitrophenyl α-d-gluco- and α-d-mannopyranosides. Carbohydr Res 2004; 339:1597-602. [PMID: 15183733 DOI: 10.1016/j.carres.2004.03.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2003] [Accepted: 03/21/2004] [Indexed: 11/18/2022]
Abstract
A chemoenzymic methodology is extended to the library synthesis of regioselectively O-sulfonated pNP D-gluco and D-mannopyranosides. The method involves the sequential reactions of chemical O-sulfonation and sulfatase-catalyzed O-desulfonation. pNP 2,6-di-O-sulfo-alpha-D-glucopyranoside and pNP 3,6-di-O-sulfo-alpha-D-mannopyranoside were obtained as sodium salts using chemical methods by way of dibutylstannylene acetals or tributylstannyl ethers. They were then applied to enzyme reactions using three molluscan enzymes (snail, limpet, and abalone). The sulfatase reactions cleaved a sulfate group at the secondary O-2 or O-3 position to yield the corresponding pNP 6-O-sulfo sugars. Neither pNP 6-O-sulfo-alpha-D-glucopyranoside nor 6-O-sulfo-alpha-D-mannopyranoside became the enzyme substrate. Evidently, the molluscan sulfatases have a tendency to cleave the secondary O-sulfo group with assistance from the 6-O-sulfo group.
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Affiliation(s)
- Hirotaka Uzawa
- Research Center of Advanced Bionics, National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1 Higashi, Tsukuba 305-8565, Japan.
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Organic Compatible Solutes. CELLULAR ORIGIN, LIFE IN EXTREME HABITATS AND ASTROBIOLOGY 2003. [DOI: 10.1007/0-306-48053-0_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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Kokoeva MV, Storch KF, Klein C, Oesterhelt D. A novel mode of sensory transduction in archaea: binding protein-mediated chemotaxis towards osmoprotectants and amino acids. EMBO J 2002; 21:2312-22. [PMID: 12006484 PMCID: PMC125379 DOI: 10.1093/emboj/21.10.2312] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Directly upstream of the Halobacterium salinarum transducer genes basT and htpIV we identified two open reading frames (orfs) with significant homologies to genes encoding binding proteins for amino acids and compatible solutes, respectively. Behavioral testing of deletion mutants indicates that halobacterial chemotaxis towards branched-chain amino acids as well as compatible osmolytes of the betaine family requires both a binding and a transducer protein. We therefore named the binding/transducer proteins BasB/BasT for branched-chain and sulfur-containing amino acids and CosB/CosT for compatible solutes. Our data support a signaling mechanism with the binding proteins functioning as lipid-anchored receptors interacting with the extracellular domain of their cognate transducers. Inspection of the halobacterial genome suggests that BasB and CosB exclusively mediate chemotaxis responses without any additional role in transport, which is in contrast to bacterial binding proteins, which are always part of ABC transport systems. The CosB/CosT system is the first instance of a chemotaxis signaling pathway for organic osmolytes in the living world and natural abundance 13C-NMR analysis of cytoplasmic extracts suggests that H.salinarum utilizes these solutes for osmotic adaptation.
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Affiliation(s)
- Maia V. Kokoeva
- Max-Planck Institut für Biochemie, D-82152 Martinsried, Germany
Present address: Division of Endocrinology, Beth Israel Diaconess Medical Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA Present address: Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA Corresponding author e-mail: M.V.Kokoeva and K.-F.Storch contributed equally to this work
| | - Kai-Florian Storch
- Max-Planck Institut für Biochemie, D-82152 Martinsried, Germany
Present address: Division of Endocrinology, Beth Israel Diaconess Medical Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA Present address: Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA Corresponding author e-mail: M.V.Kokoeva and K.-F.Storch contributed equally to this work
| | | | - Dieter Oesterhelt
- Max-Planck Institut für Biochemie, D-82152 Martinsried, Germany
Present address: Division of Endocrinology, Beth Israel Diaconess Medical Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA Present address: Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA Corresponding author e-mail: M.V.Kokoeva and K.-F.Storch contributed equally to this work
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Abstract
The availability of water is the most important prerequisite for life of any living cell, and exposure of cells to hypersaline conditions always threatens the cells with a drastic loss of water. To re-establish the essential turgor pressure, cells increase the water activity of their cytoplasm by accumulation of compatible solutes, either by synthesis or by uptake. The ability to respond to increasing osmolality is well conserved in all three lines of descent and, here, we compare the osmoadaptive strategies of Bacteria and Archaea. The temporal sequence of events after an osmotic upshock will be discussed, with a focus on the most rapid response, notably the mechanisms of transport activation at the protein level, and different signals for osmolality will be compared. The spectrum of compatible solutes used by different organisms is rather diverse and a comparison of 'bacterial' and 'archaeal' compatible solutes will be given.
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Affiliation(s)
- M Roesser
- Lehrstuhl für Mikrobiologie der LMU München, 80638 München, Germany
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Romano I, Nicolaus B, Lama L, Trabasso D, Caracciolo G, Gambacorta A. Accumulation of osmoprotectants and lipid pattern modulation in response to growth conditions by Halomonas pantelleriense. Syst Appl Microbiol 2001; 24:342-52. [PMID: 11822668 DOI: 10.1078/0723-2020-00046] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The effects of salinity, growth temperature, pH and composition of the medium on the accumulation of intracellular organic solutes, by nuclear magnetic resonance spectroscopy (NMR) in Halomonas pantelleriense were examined. The modulation of lipid pattern in different growth conditions was also reported. H. pantelleriense accumulated glycine betaine, ectoine, hydroxyectoine and glutamate. The type of osmoprotectant and the relative proportion depended on growth conditions. The main lipids identified by NMR studies were 1,2 diacylglycero-3-phosphorylethanolamine (PEA), 1,2 diacylglycero-3-phosphoryl-glycerol (PG) and cardiolipin, (DPG). The predominant fatty acids were C16:0 and C18:1, minor fatty acids were C16:1 and C18:0. The relative percentage of polar lipids and fatty acids were affected by growth conditions.
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Affiliation(s)
- I Romano
- Istituto per la Chimica di Molecole di Interesse Biologico, CNR, Comprensorio ex-Olivetti Fabbricato 70, Pozzuoli, Na, Italy
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Affiliation(s)
- H Santos
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras 2780-156, Portugal
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