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Carrizo D, Vignale FA, Sánchez-García L, Farías ME. Ecological variability based on lipid biomarkers in astrobiologically interesting wetlands from the Argentinian central Andes. FEMS Microbiol Ecol 2022; 98:6575537. [PMID: 35482603 DOI: 10.1093/femsec/fiac049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 04/01/2022] [Accepted: 04/25/2022] [Indexed: 11/13/2022] Open
Abstract
Andean wetlands hold extremophilic communities adapted to live in harsh conditions. Here, we investigated the microbial ecology of three high-altitude hypersaline ponds from La Puna region (Argentina) showing an increasing extent of desiccation by analyzing their lipid sedimentary record. We recreated the microbial community structure and the carbon metabolisms in each lacustrine system based on the molecular distribution of lipid biomarkers and their compound-specific carbon and hydrogen isotopic signatures. We detected lipid compounds considered to be biomarkers of cyanobacteria, sulfate-reducing bacteria, purple sulfur bacteria, and archaea in the three Andean ponds, as well as diatoms in the intermediate salinity system. The relative abundance of purple sulfur and sulfate-reducing bacteria decreased with salinity, whereas cyanobacteria and archaea decreased their relative abundance in the mid-saline pond to increase it again and became both prevailing at the highest salinity. Carbon fixation in the three ponds was driven by a combination of the reductive tricarboxylic acid cycle, the reductive pentose phosphate cycle, and the reductive acetyl-CoA pathway. This work is the first to describe molecular and isotopic lipid fingerprints in wetlands from the central Andean Puna, and serves as a basis for further biogeochemical studies in the area.
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Affiliation(s)
- Daniel Carrizo
- Centro de Astrobiología (CSIC-INTA), Department of Planetology and Habitability, Madrid, Spain
| | - Federico A Vignale
- Laboratorio de Investigaciones Microbiológicas de Lagunas Andinas (LIMLA), Planta Piloto de Procesos Industriales Microbiológicos (PROIMI)-CCT-CONICET, San Miguel de Tucumán, Tucumán, T4001MVB, Argentina.,Laboratorio de Bioinformática Estructural, Instituto de Química Biológica de la Facultad de Ciencias Exactas y Naturales (IQUIBICEN)-CONICET, Universidad de Buenos Aires (UBA), Buenos Aires, C1428EHA, Argentina
| | - Laura Sánchez-García
- Centro de Astrobiología (CSIC-INTA), Department of Molecular Evolution, Madrid, Spain
| | - María E Farías
- Laboratorio de Investigaciones Microbiológicas de Lagunas Andinas (LIMLA), Planta Piloto de Procesos Industriales Microbiológicos (PROIMI)-CCT-CONICET, San Miguel de Tucumán, Tucumán, T4001MVB, Argentina
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2
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Influence of Temperature and Sulfate Concentration on the Sulfate/Sulfite Reduction Prokaryotic Communities in the Tibetan Hot Springs. Microorganisms 2021; 9:microorganisms9030583. [PMID: 33809110 PMCID: PMC8002027 DOI: 10.3390/microorganisms9030583] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 03/05/2021] [Accepted: 03/09/2021] [Indexed: 11/18/2022] Open
Abstract
The distribution and diversity of sulfate/sulfite reduction prokaryotic (SRP) communities in hot springs from the Quzhuomu and Daggyai Geothermal Zone of Tibetan, China, was reported for the first time. In hot springs that are naturally hyperthermal and anoxic, the sulfur cycle is one of the most active cycles of the elements. The distribution of SRP in response to temperature is of great importance to the understanding of biogeochemical cycling of sulfur in geothermal features. Little is known about the SRP in geothermal zone. In this study, the diversity of SRP was investigated in the sediments from the Daggyai and Quzhuomu geothermal zone using PCR amplification, cloning and sequencing of the dissimilatory sulfite reductase beta subunit gene (dsrB). The abundance of dsrB and 16S rRNA genes, were determined by quantitative polymerase chain reactions. In addition, correlations of the SRP assemblages with environmental factors were analyzed by the aggregated boosted tree (ABT) statistical analysis. The results showed that SRP populations were diverse, but were mainly composed of Desulfobacterales, Desulfovibrionales, Syntrophobacterales, Clostridia and Nitrospirales, and large fraction (25%) of novel sequences have branched groups in the dsrB phylogenetic tree. In Quzhuomu geothermal zone, sulfate-rich hot springs are characterized by thick bacterial mats that are green or red and the SRP populations mainly appear at mid-temperature (50 °C to 70 °C). In low-sulfate hot springs in the Daggyai geothermal zone, although gray or pink streamers are widely formed at 60 °C to 80 °C, they prefer to inhabit in green mat at lower temperature (30 °C to 50 °C). With increasing temperature, the diversity of the dsrB gene at the OTU level (cutoff 97%) decreased, while its relative abundance increased. This result suggests that temperature played an important role in affecting dsrB gene distribution.
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3
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Sánchez-García L, Carrizo D, Molina A, Muñoz-Iglesias V, Lezcano MÁ, Fernández-Sampedro M, Parro V, Prieto-Ballesteros O. Fingerprinting molecular and isotopic biosignatures on different hydrothermal scenarios of Iceland, an acidic and sulfur-rich Mars analog. Sci Rep 2020; 10:21196. [PMID: 33273669 PMCID: PMC7712778 DOI: 10.1038/s41598-020-78240-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 11/23/2020] [Indexed: 11/09/2022] Open
Abstract
Detecting signs of potential extant/extinct life on Mars is challenging because the presence of organics on that planet is expected to be very low and most likely linked to radiation-protected refugia and/or preservative strategies (e.g., organo-mineral complexes). With scarcity of organics, accounting for biomineralization and potential relationships between biomarkers, mineralogy, and geochemistry is key in the search for extraterrestrial life. Here we explored microbial fingerprints and their associated mineralogy in Icelandic hydrothermal systems analog to Mars (i.e., high sulfur content, or amorphous silica), to identify potentially habitable locations on that planet. The mineralogical assemblage of four hydrothermal substrates (hot springs biofilms, mud pots, and steaming and inactive fumaroles) was analyzed concerning the distribution of biomarkers. Molecular and isotopic composition of lipids revealed quantitative and compositional differences apparently impacted by surface geothermal alteration and environmental factors. pH and water showed an influence (i.e., greatest biomass in circumneutral settings with highest supply and turnover of water), whereas temperature conditioned the mineralogy that supported specific microbial metabolisms related with sulfur. Raman spectra suggested the possible coexistence of abiotic and biomediated sources of minerals (i.e., sulfur or hematite). These findings may help to interpret future Raman or GC-MS signals in forthcoming Martian missions.
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Affiliation(s)
| | - Daniel Carrizo
- Centro de Astrobiología (CSIC-INTA), Carretera de Ajalvir km 4, Madrid, Spain
| | - Antonio Molina
- Centro de Astrobiología (CSIC-INTA), Carretera de Ajalvir km 4, Madrid, Spain
| | | | | | | | - Victor Parro
- Centro de Astrobiología (CSIC-INTA), Carretera de Ajalvir km 4, Madrid, Spain
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4
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Fadhlaoui M, Laderriere V, Lavoie I, Fortin C. Influence of Temperature and Nickel on Algal Biofilm Fatty Acid Composition. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2020; 39:1566-1577. [PMID: 32367541 DOI: 10.1002/etc.4741] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/19/2020] [Accepted: 04/30/2020] [Indexed: 06/11/2023]
Abstract
Freshwater biofilms play an important role in aquatic ecosystems and are widely used to evaluate environmental conditions. Little is known about the effects of temperature and metals on biofilm fatty acid composition. In the present study, we exposed a natural biofilm cultured in mesocosms to a gradient of nickel (Ni) concentrations at 15 and 21 °C for 28 d. Metal bioaccumulation, algal taxonomic composition, and biofilm fatty acid profiles were determined. At both temperatures, bioaccumulated Ni increased with Ni exposure concentration and reached the highest values at 25 µM Ni, followed by a decrease at 55 and 105 µM Ni. In control biofilms, palmitic acid (16:0), palmitoleic acid (16:1n7), oleic acid (18:1n9), linoleic acid (18:2n6), and linolenic acid (18:3n3) were the dominant fatty acids at 15 and 21 °C. This composition suggests a dominance of cyanobacteria and green algae, which was subsequently confirmed by microscopic observations. The increase in temperature resulted in a decrease in the ratio of unsaturated to saturated fatty acids, which is considered to be an adaptive response to temperature variation. Polyunsaturated fatty acids (PUFAs) tended to decrease along the Ni gradient, as opposed to saturated fatty acids which increased with Ni concentrations. Temperature and Ni affected differently the estimated desaturase and elongase activities (product/precursor ratios). The increase in PUFAs at 15 °C was concomitant to an increase in Δ9-desaturase (D9D). The estimated activities of D9D, Δ12-desaturase, and Δ15-desaturase decreased along the Ni gradient and reflected a decline in PUFAs. The elevated estimated elongase activity reflected the observed increase in saturated fatty acids at the highest Ni exposure concentration (105 µM). Our results suggest that fatty acids could be used as an endpoint to evaluate environmental perturbations. Environ Toxicol Chem 2020;39:1566-1577. © 2020 SETAC.
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Affiliation(s)
- Mariem Fadhlaoui
- Institut national de la recherche scientifique, Centre Eau Terre Environnement, Québec, Québec, Canada
| | - Vincent Laderriere
- Institut national de la recherche scientifique, Centre Eau Terre Environnement, Québec, Québec, Canada
| | - Isabelle Lavoie
- Institut national de la recherche scientifique, Centre Eau Terre Environnement, Québec, Québec, Canada
| | - Claude Fortin
- Institut national de la recherche scientifique, Centre Eau Terre Environnement, Québec, Québec, Canada
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5
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Antonucci M, Belghit I, Truzzi C, Illuminati S, Araujo P. Modeling the influence of time and temperature on the levels of fatty acids in the liver of Antarctic fish Trematomus bernacchii. Polar Biol 2019. [DOI: 10.1007/s00300-019-02577-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Abstract
Antarctic fish (Trematomus bernacchii) are an ideal group for studying the effect of ocean warming on vital physiological and biochemical mechanisms of adaptation, including changes in the fatty acid composition to higher heat tolerance in the sub-zero waters of the Southern Ocean. Despite the awareness of the impact of ocean warming on marine life, bioclimatic models describing the effect of temperature and time on fatty acid levels in marine species have not been considered yet. The objective of the present study was to investigate changes in the concentrations of fatty acids in liver from T. bernacchii in response to an increase in temperature in the Antarctic region. Changes in the concentrations of fatty acids in liver from T. bernacchii were observed after varying simultaneously and systematically the temperature and time. The fatty acid profiles were determined by gas chromatography prior to acclimation (− 1.8 °C) and after acclimation (0.0, 1.0, and 2.0 °C) at different times (1, 5, and 10 days). The observed changes were graphically visualized by expressing the fatty acid concentration in absolute units (mg g−1) as a function of the temperature and time using polynomial models. Major changes in fatty acid composition were observed at day 1 of exposition at all temperatures. At day 5, the fish seem to tolerate the new temperature condition. The concentrations of saturated fatty acids were almost constant throughout the various conditions. The concentrations of monounsaturated fatty acids (in particular 18:1n − 9) decrease at day 1 for all temperatures. In contrast, there was an increase in the concentrations of polyunsaturated fatty acids (in particular 20:5n − 3 and 22:6n − 3) with increasing temperatures after 1, 5, and 10 days of exposure. The proposed models were in agreement with reported studies on polar and temperate fish, indicating possibly similar adaptation mechanisms for teleost to cope with global warming.
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6
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Králová S. Role of fatty acids in cold adaptation of Antarctic psychrophilic Flavobacterium spp. Syst Appl Microbiol 2017; 40:329-333. [DOI: 10.1016/j.syapm.2017.06.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 06/08/2017] [Accepted: 06/12/2017] [Indexed: 10/19/2022]
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7
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Singh A, Krishnan KP, Prabaharan D, Sinha RK. Lipid membrane modulation and pigmentation: A cryoprotection mechanism in Arctic pigmented bacteria. J Basic Microbiol 2017; 57:770-780. [DOI: 10.1002/jobm.201700182] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 05/31/2017] [Accepted: 06/06/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Archana Singh
- National Centre for Antarctic and Ocean Research; Headland Sada; Vasco-da-Gama Goa India
| | - Kottekattu P. Krishnan
- National Centre for Antarctic and Ocean Research; Headland Sada; Vasco-da-Gama Goa India
| | - Dharmar Prabaharan
- National Facility for Marine Cyanobacteria; Bharathidasan University; Tiruchirappalli Tamil Nadu India
| | - Rupesh K. Sinha
- National Centre for Antarctic and Ocean Research; Headland Sada; Vasco-da-Gama Goa India
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8
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Membrane fluidity-related adaptive response mechanisms of foodborne bacterial pathogens under environmental stresses. Food Res Int 2015. [DOI: 10.1016/j.foodres.2015.03.016] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Miyazaki M, Sakai S, Yamanaka Y, Saito Y, Takai K, Imachi H. Spirochaeta psychrophila sp. nov., a psychrophilic spirochaete isolated from subseafloor sediment, and emended description of the genus Spirochaeta. Int J Syst Evol Microbiol 2014; 64:2798-2804. [DOI: 10.1099/ijs.0.062463-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
An obligately anaerobic, psychrophilic spirochaete, strain MO-SPC1T, was isolated from a methanogenic microbial community grown in a continuous-flow bioreactor. Originally, this community was obtained from subseafloor sediments off the Shimokita Peninsula of Japan in the north-western Pacific Ocean. The cells were motile, Gram-stain-negative, helical, 0.25–0.55×3.6–15 µm, with a wavelength of approximately 0.5–0.6 µm. Strain MO-SPC1T grew at 0–18 °C (optimally at 15 °C), at pH 6.0–7.5 (optimally at pH 6.8–7.0) and in 20–70 g NaCl l−1 (optimally at 30–40 NaCl l−1). The strain grew chemo-organotrophically with mono-, di- and polysaccharides. The major end products of glucose fermentation were acetate, ethanol, hydrogen and carbon dioxide. The abundant polar lipids of strain MO-SPC1T were diphosphatidylglycerol, phosphatidylglycerol, unknown phospholipids and an unknown lipid. The major cellular fatty acids (>5 % of the total) were C14 : 0, C16 : 0, iso-C13 : 0, iso-C14 : 0, iso-C15 : 0, anteiso-C13 : 0 and anteiso-C15 : 0. To the best of our knowledge, this is the first report of the fatty acids iso-C13 : 0 and anteiso-C13 : 0 from a species of the genus
Spirochaeta
. Isoprenoid quinones were not found. The G+C content of the genomic DNA was 39.8 mol%. 16S rRNA gene sequence-based phylogenetic analysis showed that strain MO-SPC1T was affiliated with the genus
Spirochaeta
, and its closest relatives were
Spirochaeta isovalerica
MA-2T (95.6 % sequence identity) and
Spirochaeta litoralis
R1T (89.4 %). Based on its phenotypic characteristics and phylogenetic traits, strain MO-SPC1T is placed in a separate taxon at the level of a novel species within the genus
Spirochaeta,
for which the name Spirochaeta psychrophila sp. nov. is proposed, reflecting its true psychrophilic physiology. The type strain is MO-SPC1T ( = JCM 17280T = DSM 23951T). To our knowledge, this is the first report of an isolate of the phylum
Spirochaetes
from a deep-sea sedimentary environment, and of an obligately psychrophilic nature.
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Affiliation(s)
- Masayuki Miyazaki
- Department of Subsurface Geobiology Analysis and Research (D-SUGAR), Japan Agency for Marine-Earth Science & Technology (JAMSTEC), Yokosuka, Kanagawa 237-0061, Japan
| | - Sanae Sakai
- Department of Subsurface Geobiology Analysis and Research (D-SUGAR), Japan Agency for Marine-Earth Science & Technology (JAMSTEC), Yokosuka, Kanagawa 237-0061, Japan
| | - Yuko Yamanaka
- Department of Subsurface Geobiology Analysis and Research (D-SUGAR), Japan Agency for Marine-Earth Science & Technology (JAMSTEC), Yokosuka, Kanagawa 237-0061, Japan
| | - Yumi Saito
- Department of Subsurface Geobiology Analysis and Research (D-SUGAR), Japan Agency for Marine-Earth Science & Technology (JAMSTEC), Yokosuka, Kanagawa 237-0061, Japan
| | - Ken Takai
- Department of Subsurface Geobiology Analysis and Research (D-SUGAR), Japan Agency for Marine-Earth Science & Technology (JAMSTEC), Yokosuka, Kanagawa 237-0061, Japan
| | - Hiroyuki Imachi
- Department of Subsurface Geobiology Analysis and Research (D-SUGAR), Japan Agency for Marine-Earth Science & Technology (JAMSTEC), Yokosuka, Kanagawa 237-0061, Japan
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10
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Zhao J, Wan S, Zhang C, Liu Z, Zhou L, Fu S. Contributions of understory and/or overstory vegetations to soil microbial PLFA and nematode diversities in Eucalyptus monocultures. PLoS One 2014; 9:e85513. [PMID: 24427315 PMCID: PMC3888421 DOI: 10.1371/journal.pone.0085513] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 11/27/2013] [Indexed: 11/19/2022] Open
Abstract
Ecological interactions between aboveground and belowground biodiversity have received many attentions in the recent decades. Although soil biodiversity declined with the decrease of plant diversity, many previous studies found plant species identities were more important than plant diversity in controlling soil biodiversity. This study focused on the responses of soil biodiversity to the altering of plant functional groups, namely overstory and understory vegetations, rather than plant diversity gradient. We conducted an experiment by removing overstory and/or understory vegetation to compare their effects on soil microbial phospholipid fatty acid (PLFA) and nematode diversities in eucalyptus monocultures. Our results indicated that both overstory and understory vegetations could affect soil microbial PLFA and nematode diversities, which manifested as the decrease in Shannon-Wiener diversity index (H') and Pielou evenness index (J) and the increase in Simpson dominance index (λ) after vegetation removal. Soil microclimate change explained part of variance of soil biodiversity indices. Both overstory and understory vegetations positively correlated with soil microbial PLFA and nematode diversities. In addition, the alteration of soil biodiversity might be due to a mixing effect of bottom-up control and soil microclimate change after vegetation removal in the studied plantations. Given the studied ecosystem is common in humid subtropical and tropical region of the world, our findings might have great potential to extrapolate to large scales and could be conducive to ecosystem management and service.
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Affiliation(s)
- Jie Zhao
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
- Key Laboratory of Agro-Ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Songze Wan
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Chenlu Zhang
- State Key Laboratory of Cotton Biology, Key Laboratory of Plant Stress Biology, College of Life Sciences, Henan University, Kaifeng, China
| | - Zhanfeng Liu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Lixia Zhou
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Shenglei Fu
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
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11
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Moser R, Aktas M, Narberhaus F. Phosphatidylcholine biosynthesis inXanthomonas campestrisvia a yeast-like acylation pathway. Mol Microbiol 2014; 91:736-50. [DOI: 10.1111/mmi.12492] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/10/2013] [Indexed: 12/01/2022]
Affiliation(s)
- Roman Moser
- Microbial Biology; Ruhr University Bochum; Bochum Germany
| | - Meriyem Aktas
- Microbial Biology; Ruhr University Bochum; Bochum Germany
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12
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Könneke M, Kuever J, Galushko A, Jørgensen BB. Desulfoconvexum algidum gen. nov., sp. nov., a psychrophilic sulfate-reducing bacterium isolated from a permanently cold marine sediment. Int J Syst Evol Microbiol 2012; 63:959-964. [PMID: 22659505 DOI: 10.1099/ijs.0.043703-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A sulfate-reducing bacterium, designated JHA1(T), was isolated from a permanently cold marine sediment sampled in an Artic fjord on the north-west coast of Svalbard. The isolate was originally enriched at 4 °C in a highly diluted liquid culture amended with hydrogen and sulfate. Strain JHA1(T) was a psychrophile, growing fastest between 14 and 16 °C and not growing above 20 °C. Fastest growth was found at neutral pH (pH 7.2-7.4) and at marine concentrations of NaCl (20-30 g l(-1)). Phylogenetic analysis of 16S rRNA gene sequences revealed that strain JHA1(T) was a member of the family Desulfobacteraceae in the Deltaproteobacteria. The isolate shared 99 % 16S rRNA gene sequence similarity with an environmental sequence obtained from permanently cold Antarctic sediment. The closest recognized relatives were Desulfobacula phenolica DSM 3384(T) and Desulfobacula toluolica DSM 7467(T) (both <95 % sequence similarity). In contrast to its closest phylogenetic relatives, strain JHA1(T) grew chemolithoautotrophically with hydrogen as an electron donor. CO dehydrogenase activity indicated the operation of the reductive acetyl-CoA pathway for inorganic carbon assimilation. Beside differences in physiology and morphology, strain JHA1(T) could be distinguished chemotaxonomically from the genus Desulfobacula by the absence of the cellular fatty acid C16 : 0 10-methyl. Phylogenetic differentiation from other genera was further supported by DsrAB and AprBA sequence analysis. Based on the described phylogenetic and phenotypic differences between strain JHA1(T) and its closest relatives, the establishment of a novel genus and a novel species, Desulfoconvexum algidum gen. nov., sp. nov. is proposed. The type strain is JHA1(T) ( = DSM 21856(T) = JCM 16085(T)).
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Affiliation(s)
- Martin Könneke
- Max-Planck Institute for Marine Microbiology, Bremen, Germany
| | - Jan Kuever
- Bremen Institute for Materials Testing, Bremen, Germany
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13
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Duldhardt I, Gaebel J, Chrzanowski L, Nijenhuis I, Härtig C, Schauer F, Heipieper HJ. Adaptation of anaerobically grown Thauera aromatica, Geobacter sulfurreducens and Desulfococcus multivorans to organic solvents on the level of membrane fatty acid composition. Microb Biotechnol 2009; 3:201-9. [PMID: 21255320 PMCID: PMC3836581 DOI: 10.1111/j.1751-7915.2009.00124.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The effect of different solvents and pollutants on the cellular fatty acid composition of three bacterial strains: Thauera aromatica, Geobacter sulfurreducens and Desulfococcus multivorans, representatives of diverse predominant anaerobic metabolisms was investigated. As the prevailing adaptive mechanism in cells of T. aromatica and G. sulfurreducens whose cellular fatty acids patterns were dominated by palmitic acid (C16:0) and palmitoleic acid (C16:1cis), the cells reacted by an increase in the degree of saturation of their membrane fatty acids when grown in the presence of sublethal concentrations of the chemicals. Next to palmitic acid C16:0, the fatty acid pattern of D. multivorans was dominated by anteiso‐branched fatty acids which are characteristic for several sulfate‐reducing bacteria. The cells responded to the solvents with an increase in the ratio of straight‐chain saturated (C14:0, C16:0, C18:0) to anteiso‐branched fatty acids (C15:0anteiso, C17:0anteiso, C17:1anteisoΔ9cis). The results show that anaerobic bacteria react with similar mechanisms like aerobic bacteria in order to adapt their membrane to toxic organic solvents. The observed adaptive modifications on the level of membrane fatty acid composition can only be carried out with de novo synthesis of the fatty acids which is strictly related to cell growth. As the growth rates of anaerobic bacteria are generally much lower than in the so far investigated aerobic bacteria, this adaptive response needs more time in anaerobic bacteria. This might be one explanation for the previously observed higher sensitivity of anaerobic bacteria when compared with aerobic ones.
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Affiliation(s)
- Ilka Duldhardt
- Departments of Environmental Biotechnology, Helmholtz Centre for Environmental Research - UFZ, Permoserstr. 15, 04318 Leipzig, Germany
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14
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Freese E, Rütters H, Köster J, Rullkötter J, Sass H. Gammaproteobacteria as a possible source of eicosapentaenoic acid in anoxic intertidal sediments. MICROBIAL ECOLOGY 2009; 57:444-454. [PMID: 18777187 DOI: 10.1007/s00248-008-9443-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Accepted: 08/18/2008] [Indexed: 05/26/2023]
Abstract
Eicosapentaenoic acid (EPA; n-20:5omega3) was found to be a constituent of phospholipids in three mesophilic strains of Gammaproteobacteria, which were isolated from anoxic most probable number series prepared with sediments from an intertidal flat of the German North Sea coast. Their partial 16S rRNA gene sequences identified the isolates as close relatives of Shewanella colwelliana, Vibrio splendidus, and Photobacterium lipolyticum. So far, eicosapentaenoic acid has mainly been reported to occur in eukaryotes and some piezophilic or psychrophilic bacteria. With decreasing temperature, relative contents of EPA (up to 14% of total fatty acids) increased in all strains. Additionally, Shewanella and Vibrio spp. showed a significant increase in monounsaturated fatty acids with lower growth temperature. Analysis of the phospholipid compositions revealed that EPA was present in all three major phospholipid types, namely, phosphatidyl glycerol (PG), cardiolipin and phosphatidyl ethanolamine (PE). However, EPA was enriched in PG and cardiolipin relative to PE. In the tidal flat sediments from which the isolates were obtained, substantial amounts of EPA-containing PG were detected, whereas other typical microeukaryotic phospholipids-being also a possible source of EPA-were abundant at the sediment surface but were present in clearly lower amounts in the anoxic layers beneath 5 cm depth. Therefore, the EPA-containing PG species in the deeper layers in these sediments may indicate the presence of Gammaproteobacteria closely related to the isolates. These bacteria appear to be an important source of EPA in buried, anoxic sediments beneath the layers harboring significant populations of benthic eukaryotes.
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Affiliation(s)
- Elke Freese
- Institute of Chemistry and Biology of the Marine Environment (ICBM), Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
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Fidorra M, Heimburg T, Seeger H. Melting of individual lipid components in binary lipid mixtures studied by FTIR spectroscopy, DSC and Monte Carlo simulations. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2009; 1788:600-7. [DOI: 10.1016/j.bbamem.2008.12.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Revised: 11/25/2008] [Accepted: 12/01/2008] [Indexed: 11/26/2022]
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Verminephrobacter eiseniae gen. nov., sp. nov., a nephridial symbiont of the earthworm Eisenia foetida (Savigny). Int J Syst Evol Microbiol 2008; 58:2147-57. [DOI: 10.1099/ijs.0.65174-0] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Tarpgaard IH, Boetius A, Finster K. Desulfobacter psychrotolerans sp. nov., a new psychrotolerant sulfate-reducing bacterium and descriptions of its physiological response to temperature changes. Antonie van Leeuwenhoek 2005; 89:109-24. [PMID: 16328859 DOI: 10.1007/s10482-005-9014-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Accepted: 09/15/2005] [Indexed: 11/25/2022]
Abstract
A psychrotrolerant acetate-oxidizing sulfate-reducing bacterium (strain akvb(T)) was isolated from sediment from the northern part of The North Sea with annual temperature fluctuations between 8 and 14 degrees C. Of the various substrates tested, strain akvb(T) grew exclusively by the oxidation of acetate coupled to the reduction of sulfate. The cells were motile, thick rods with round ends and grew in dense aggregates. Strain akvb(T) grew at temperatures ranging from -3.6 to 26.3 degrees C. Optimal growth was observed at 20 degrees C. The highest cell specific sulfate reduction rate of 6.2 fmol cell(-1) d(-1) determined by the (35)SO(2-)(40) method was measured at 26 degrees C. The temperature range of short-term sulfate reduction rates exceeded the temperature range of growth by 5 degrees C. The Arrhenius relationship for the temperature dependence of growth and sulfate reduction was linear, with two distinct slopes below the optimum temperatures of both processes. The critical temperature was 6.4 degrees C. The highest growth yield (4.3-4.5 g dry weight mol(-1) acetate) was determined at temperatures between 5 and 15 degrees C. The cellular fatty acid composition was determined with cultures grown at 4 and 20 degrees C, respectively. The relative proportion of cellular unsaturated fatty acids (e.g. 16:1omega7c) was higher in cells grown at 4 degrees C than in cells grown at 20 degrees C. The physiological responses to temperature changes showed that strain akvb(T) was well adapted to the temperature regime of the environment from which it was isolated. Phylogenetic analysis showed that strain akvb(T) is closest related to Desulfobacter hydrogenophilus, with a 16S rRNA gene sequence similarity of 98.6%. DNA-DNA-hybridization showed a similarity of 32% between D. hydrogenophilus and strain akvb(T). Based on phenotypic and DNA-based characteristics we propose that strain akvb(T) is a member of a new species, Desulfobacter psychrotolerans sp. nov.
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Affiliation(s)
- Irene H Tarpgaard
- Department of Microbiology, Bldg. 540, Institute of Biological Sciences, University of Aarhus, 8000 Aarhus, Denmark
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Affiliation(s)
- Barbara Methé
- The Institute for Genomic Research, 9712 Medical Center Drive, Rockville, MD 20850, USA
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Rabus R, Ruepp A, Frickey T, Rattei T, Fartmann B, Stark M, Bauer M, Zibat A, Lombardot T, Becker I, Amann J, Gellner K, Teeling H, Leuschner WD, Glöckner FO, Lupas AN, Amann R, Klenk HP. The genome of Desulfotalea psychrophila, a sulfate-reducing bacterium from permanently cold Arctic sediments. Environ Microbiol 2004; 6:887-902. [PMID: 15305914 DOI: 10.1111/j.1462-2920.2004.00665.x] [Citation(s) in RCA: 158] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Desulfotalea psychrophila is a marine sulfate-reducing delta-proteobacterium that is able to grow at in situ temperatures below 0 degrees C. As abundant members of the microbial community in permanently cold marine sediments, D. psychrophila-like bacteria contribute to the global cycles of carbon and sulfur. Here, we describe the genome sequence of D. psychrophila strain LSv54, which consists of a 3 523 383 bp circular chromosome with 3118 predicted genes and two plasmids of 121 586 bp and 14 663 bp. Analysis of the genome gave insight into the metabolic properties of the organism, e.g. the presence of TRAP-T systems as a major route for the uptake of C(4)-dicarboxylates, the unexpected presence of genes from the TCA cycle, a TAT secretion system, the lack of a beta-oxidation complex and typical Desulfovibrio cytochromes, such as c(553), c(3) and ncc. D. psychrophila encodes more than 30 two-component regulatory systems, including a new Ntr subcluster of hybrid kinases, nine putative cold shock proteins and nine potentially cold shock-inducible proteins. A comparison of D. psychrophila's genome features with those of the only other published genome from a sulfate reducer, the hyperthermophilic archaeon Archaeoglobus fulgidus, revealed many striking differences, but only a few shared features.
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Affiliation(s)
- R Rabus
- Max-Planck-Institute for Marine Microbiology, Celsiusstrasse 1, 28359 Bremen, Germany
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