scholarly journals Psychromonas boydii sp. nov., a gas-vacuolate, psychrophilic bacterium isolated from an Arctic sea-ice core

2010 ◽  
Vol 60 (1) ◽  
pp. 84-92 ◽  
Author(s):  
Ann J. Auman ◽  
Jennifer L. Breezee ◽  
John J. Gosink ◽  
Peter Schumann ◽  
Carmen R. Barnes ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Sea Ice ◽  
Fatty Acid Content ◽  
Ice Core ◽  
Carbon Sources ◽  
Distinct Species ◽  
Arctic Sea Ice ◽  
Rrna Gene ◽  
Psychrophilic Bacterium ◽  
Phenotypic Analysis

A gas-vacuolate bacterium, strain 174T, was isolated from a sea-ice core collected from Point Barrow, Alaska, USA. Comparative analysis of 16S rRNA gene sequences showed that this bacterium was most closely related to Psychromonas ingrahamii 37T, with a similarity of >99 %. However, strain 174T could be clearly distinguished from closely related species by DNA–DNA hybridization; relatedness values determined by two different methods between strain 174T and P. ingrahamii 37T were 58.4 and 55.7 % and those between strain 174T and Psychromonas antarctica DSM 10704T were 46.1 and 33.1 %, which are well below the 70 % level used to define a distinct species. Phenotypic analysis, including cell size (strain 174T is the largest member of the genus Psychromonas, with rod-shaped cells, 8–18 μm long), further differentiated strain 174T from other members of the genus Psychromonas. Strain 174T could be distinguished from its closest relative, P. ingrahamii, by its utilization of d-mannose and d-xylose as sole carbon sources, its ability to ferment myo-inositol and its inability to use fumarate and glycerol as sole carbon sources. In addition, strain 174T contained gas vacuoles of two distinct morphologies and grew at temperatures ranging from below 0 to 10 °C and its optimal NaCl concentration for growth was 3.5 %. The DNA G+C content was 40 mol%. Whole-cell fatty acid analysis showed that 16 : 1ω7c and 16 : 0 comprised 44.9 and 26.4 % of the total fatty acid content, respectively. The name Psychromonas boydii sp. nov. is proposed for this novel species, with strain 174T (=DSM 17665T =CCM 7498T) as the type strain.

scholarly journals Psychromonas ingrahamii sp. nov., a novel gas vacuolate, psychrophilic bacterium isolated from Arctic polar sea ice

2006 ◽  
Vol 56 (5) ◽  
pp. 1001-1007 ◽  
Author(s):  
Ann J. Auman ◽  
Jennifer L. Breezee ◽  
John J. Gosink ◽  
Peter Kämpfer ◽  
James T. Staley
Keyword(s):  
Fatty Acid ◽  
Sea Ice ◽  
Sequence Similarity ◽  
Fatty Acid Content ◽  
Ice Core ◽  
Distinct Species ◽  
Fatty Acid Analysis ◽  
Rrna Gene ◽  
Psychrophilic Bacterium ◽  
Phenotypic Analysis

A gas vacuolate bacterium, designated strain 37T, was isolated from a sea ice core collected from Point Barrow, Alaska, USA. Cells of strain 37T were large (6–14 μm in length), rod-shaped, contained gas vacuoles of two distinct morphologies, and grew well at NaCl concentrations of 1–10 % and at temperatures of −12 to 10 °C. The DNA G+C content was 40 mol%. Whole-cell fatty acid analysis showed that 16 : 1ω7c comprised 67 % of the total fatty acid content. Phylogenetic analysis of 16S rRNA gene sequences indicated that this bacterium was closely related to members of the genus Psychromonas, with highest sequence similarity (96.8 %) to Psychromonas antarctica. Phenotypic analysis differentiated strain 37T from P. antarctica on the basis of several characteristics, including cell morphology, growth temperature range and the ability to hydrolyse polymers. DNA–DNA hybridization experiments revealed a level of relatedness of 37 % between strain 37T and P. antarctica, providing further support that it represents a distinct species. The name Psychromonas ingrahamii sp. nov. is proposed for this novel species. The type strain is 37T (=CCUG 51855T=CIP 108865T).

scholarly journals Paucibacter toxinivorans gen. nov., sp. nov., a bacterium that degrades cyclic cyanobacterial hepatotoxins microcystins and nodularin

2005 ◽  
Vol 55 (4) ◽  
pp. 1563-1568 ◽  
Author(s):  
Jarkko Rapala ◽  
Katri A. Berg ◽  
Christina Lyra ◽  
R. Maarit Niemi ◽  
Werner Manz ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
Carbon Sources ◽  
16S Rrna Gene Sequence ◽  
Rrna Gene ◽  
Rrna Gene Sequence

Thirteen bacterial isolates from lake sediment, capable of degrading cyanobacterial hepatotoxins microcystins and nodularin, were characterized by phenotypic, genetic and genomic approaches. Cells of these isolates were Gram-negative, motile by means of a single polar flagellum, oxidase-positive, weakly catalase-positive and rod-shaped. According to phenotypic characteristics (carbon utilization, fatty acid and enzyme activity profiles), the G+C content of the genomic DNA (66·1–68·0 mol%) and 16S rRNA gene sequence analysis (98·9–100 % similarity) the strains formed a single microdiverse genospecies that was most closely related to Roseateles depolymerans (95·7–96·3 % 16S rRNA gene sequence similarity). The isolates assimilated only a few carbon sources. Of the 96 carbon sources tested, Tween 40 was the only one used by all strains. The strains were able to mineralize phosphorus from organic compounds, and they had strong leucine arylamidase and chymotrypsin activities. The cellular fatty acids identified from all strains were C16 : 0 (9·8–19 %) and C17 : 1 ω7c (<1–5·8 %). The other predominant fatty acids comprised three groups: summed feature 3 (<1–2·2 %), which included C14 : 0 3-OH and C16 : 1 iso I, summed feature 4 (54–62 %), which included C16 : 1 ω7c and C15 : 0 iso OH, and summed feature 7 (8·5–28 %), which included ω7c, ω9c and ω12t forms of C18 : 1. A more detailed analysis of two strains indicated that C16 : 1 ω7c was the main fatty acid. The phylogenetic and phenotypic features separating our strains from recognized bacteria support the creation of a novel genus and species, for which the name Paucibacter toxinivorans gen. nov., sp. nov. is proposed. The type strain is 2C20T (=DSM 16998T=HAMBI 2767T=VYH 193597T).

Celerinatantimonas yamalensis sp. nov., a cold-adapted diazotrophic bacterium from a cold permafrost brine

2013 ◽  
Vol 63 (Pt_12) ◽  
pp. 4421-4427 ◽  
Author(s):  
Viktoria Shcherbakova ◽  
Nataliya Chuvilskaya ◽  
Elizaveta Rivkina ◽  
Nikita Demidov ◽  
Victoria Uchaeva ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Novel Species ◽  
Carbon Sources ◽  
Yamal Peninsula ◽  
Rrna Gene ◽  
16S Rrna Gene Sequences ◽  
Content Type ◽  
Link Type ◽  
Bacterium Strain ◽  
The Yamal Peninsula

A facultatively anaerobic nitrogen-fixing bacterium, strain C7T, was isolated from a permafrost cryopeg on the Yamal Peninsula, Russia. Comparative analysis of 16S rRNA gene sequences revealed that this bacterium was closely related to Celerinatantimonas diazotrophica S-G2-2T with a similarity of 95.5 %. Strain C7T differed from Celerinatantimonas diazotrophica in its ability to hydrolyse gelatin and inability to use d-mannose, melibiose, l-rhamnose, myo-inositol, lactose, lactulose, d-mannitol, trehalose, dl-lactate, glycogen or l-proline as sole carbon sources. In addition, strain C7T grew over a temperature range of 0–34 °C with optimum growth at 18–22 °C. The whole-cell fatty acid profile included C16 : 0, C16 : 1ω7, C18 : 1ω7, C17 cyclo and summed feature 2 [comprising C12 : 0 aldehyde and/or unknown fatty acid 10.913 (MIDI designation) and/or iso-C16 : 1/C14 : 0 3-OH]. The DNA G+C content was 44.7 mol%. Strain C7T is thus considered to represent a novel species, for which the name Celerinatantimonas yamalensis sp. nov. is proposed. The type strain is C7T ( = VKM B-2511T = DSM 21888T).

scholarly journals A 120 000-year record of sea ice in the North Atlantic?

2019 ◽  
Vol 15 (6) ◽  
pp. 2031-2051 ◽  
Author(s):  
Niccolò Maffezzoli ◽  
Paul Vallelonga ◽  
Ross Edwards ◽  
Alfonso Saiz-Lopez ◽  
Clara Turetta ◽  
...  
Keyword(s):  
Sea Ice ◽  
North Atlantic ◽  
Ice Core ◽  
Arctic Sea Ice ◽  
First Year ◽  
Sea Ice Extent ◽  
Nordic Seas ◽  
The North ◽  
Arctic Sea ◽  
The North Atlantic

Abstract. Although it has been demonstrated that the speed and magnitude of the recent Arctic sea ice decline is unprecedented for the past 1450 years, few records are available to provide a paleoclimate context for Arctic sea ice extent. Bromine enrichment in ice cores has been suggested to indicate the extent of newly formed sea ice areas. Despite the similarities among sea ice indicators and ice core bromine enrichment records, uncertainties still exist regarding the quantitative linkages between bromine reactive chemistry and the first-year sea ice surfaces. Here we present a 120 000-year record of bromine enrichment from the RECAP (REnland ice CAP) ice core, coastal east Greenland, and interpret it as a record of first-year sea ice. We compare it to existing sea ice records from marine cores and tentatively reconstruct past sea ice conditions in the North Atlantic as far north as the Fram Strait (50–85∘ N). Our interpretation implies that during the last deglaciation, the transition from multi-year to first-year sea ice started at ∼17.5 ka, synchronously with sea ice reductions observed in the eastern Nordic Seas and with the increase in North Atlantic ocean temperature. First-year sea ice reached its maximum at 12.4–11.8 ka during the Younger Dryas, after which open-water conditions started to dominate, consistent with sea ice records from the eastern Nordic Seas and the North Icelandic shelf. Our results show that over the last 120 000 years, multi-year sea ice extent was greatest during Marine Isotope Stage (MIS) 2 and possibly during MIS 4, with more extended first-year sea ice during MIS 3 and MIS 5. Sea ice extent during the Holocene (MIS 1) has been less than at any time in the last 120 000 years.

scholarly journals Pseudonocardia abyssalis sp. nov. and Pseudonocardia oceani sp. nov., two novel actinomycetes isolated from the deep Southern Ocean

2021 ◽  
Vol 71 (9) ◽  
Author(s):  
Jonathan Parra ◽  
Sylvia Soldatou ◽  
Liam M. Rooney ◽  
Katherine R. Duncan
Keyword(s):  
Fatty Acid ◽  
Southern Ocean ◽  
Type Strain ◽  
Sequence Similarity ◽  
Genomic Analysis ◽  
Distinct Species ◽  
Diaminopimelic Acid ◽  
Comparative Genomic ◽  
Rrna Gene ◽  
Content Type

The actinomycetes strains KRD168T and KRD185T were isolated from sediments collected from the deep Southern Ocean and, in this work, they are described as representing two novel species of the genus Pseudonocardia through a polyphasic approach. Despite sharing >99 % 16S rRNA gene sequence similarity with other members of the genus, comparative genomic analysis allowed species delimitation based on average nucleotide identity and digital DNA–DNA hybridization. The KRD168T genome is characterized by a size of 6.31 Mbp and a G+C content of 73.44 mol%, while the KRD185T genome has a size of 6.82 Mbp and a G+C content of 73.98 mol%. Both strains contain meso-diaminopimelic acid as the diagnostic diamino acid, glucose as the major whole-cell sugar, MK-8(H4) as a major menaquinone and iso-branched hexadecanoic acid as a major fatty acid. Biochemical and fatty acid analyses also revealed differences between these strains and their phylogenetic neighbours, supporting their status as distinct species. The names Pseudonocardia abyssalis sp. nov. (type strain KRD168T=DSM 111918T=NCIMB 15270T) and Pseudonocardia oceani (type strain KRD185T=DSM 111919T=NCIMB 15269T) are proposed.

scholarly journals Mycolicibacterium nivoides sp. nov isolated from a peat bog

2021 ◽  
Author(s):  
John L. Dahl ◽  
Wayne Gatlin III ◽  
Phuong M. Tran ◽  
Cody S. Sheik
Keyword(s):  
Fatty Acid ◽  
Type Species ◽  
Sequence Similarity ◽  
Fatty Acid Content ◽  
Antibiotic Sensitivity ◽  
Peat Bog ◽  
Rrna Gene ◽  
Content Type ◽  
Link Type ◽  
Physiological Tests

A fast-growing, non-chromogenic, acid-fast-staining bacterium (DL90T) was isolated from a peat bog in northern Minnesota. On the basis of 16S rRNA gene sequence similarity (99.8 % identity with Mycolicibacterium septicum and 98 % with Mycolicibacterium peregrinum ) and chemotaxonomic data (fatty acid content), strain DL90T represents a member of the genus Mycolicibacterium . Physiological tests (growth curves, biofilm formation, antibiotic sensitivity, colony morphologies and heat tolerance) and biochemical analysis (arylsulfatase activity and fatty acid profiles) distinguish DL90T from its closest relative M. septicum . Phylogenomic reconstruction of the ‘Fortuitium–Vaccae’ clade, digital DNA–DNA hybridization (DDH) values of 61 %, and average nucleotide identity (ANI) values of approximately 95 % indicate that DL90T is likely to be diverged from M. septicum . Thus, we propose that DL90T represents a novel species, given the name Mycolicibacterium nivoides with the type strain being isolate DL90T (=JCM 32796T=NCCB 100660T).

scholarly journals Sea ice and pollution-modulated changes in Greenland ice core methanesulfonate and bromine

2017 ◽  
Vol 13 (1) ◽  
pp. 39-59 ◽  
Author(s):  
Olivia J. Maselli ◽  
Nathan J. Chellman ◽  
Mackenzie Grieman ◽  
Lawrence Layman ◽  
Joseph R. McConnell ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ice Core ◽  
Chemical Species ◽  
Greenland Ice Sheet ◽  
Ice Cores ◽  
Arctic Sea Ice ◽  
Sea Ice Extent ◽  
Back Trajectories ◽  
Future Evolution ◽  
Source Regions

Abstract. Reconstruction of past changes in Arctic sea ice extent may be critical for understanding its future evolution. Methanesulfonate (MSA) and bromine concentrations preserved in ice cores have both been proposed as indicators of past sea ice conditions. In this study, two ice cores from central and north-eastern Greenland were analysed at sub-annual resolution for MSA (CH3SO3H) and bromine, covering the time period 1750–2010. We examine correlations between ice core MSA and the HadISST1 ICE sea ice dataset and consult back trajectories to infer the likely source regions. A strong correlation between the low-frequency MSA and bromine records during pre-industrial times indicates that both chemical species are likely linked to processes occurring on or near sea ice in the same source regions. The positive correlation between ice core MSA and bromine persists until the mid-20th century, when the acidity of Greenland ice begins to increase markedly due to increased fossil fuel emissions. After that time, MSA levels decrease as a result of declining sea ice extent but bromine levels increase. We consider several possible explanations and ultimately suggest that increased acidity, specifically nitric acid, of snow on sea ice stimulates the release of reactive Br from sea ice, resulting in increased transport and deposition on the Greenland ice sheet.

Precision Cultivation of Phaeodactylum tricornutum and Free Lipid Acid Analysis

2011 ◽  
Vol 354-355 ◽  
pp. 226-230
Author(s):  
Feng He ◽  
Peng Cheng Fu ◽  
Chun Ming Xu
Keyword(s):  
Fatty Acid ◽  
Phaeodactylum Tricornutum ◽  
Cell Concentration ◽  
Fatty Acid Content ◽  
Carbon Sources ◽  
Total Lipid Content ◽  
Biomass Accumulation ◽  
Dry Weight ◽  
Optimal Growth ◽  
Growth Conditions

Abstract：A field test was conducted on a photobioreactors for cultivaion of P. tricornutum for optimization cultivation conditions.Here,we use a flat-cuvette pohotobioreactor to control the irradiance, pH, gas composition combined with on-line monitoring by fluorometer and densitometer.By chosing the culture medium in containing glucose，sodium acetate and glycerol, to check for the biomass, cell concentration, biochemical substances and fatty acid content nearly three months . The results show that: Phaeodactylum tricornutum is not only photoautotroph but also mixotroph, which with selectivity for substance concentration and organic carbon sources, the optimum concentration of glucose is 20mmol/L, the optimal growth condition in 500mL flask contains that the temperature is 25±1°C, the light intensity is 50µmol/m2.s, the pH is 8.5. Whatever the carbon sources are able to promote the biomass accumulation. When the cell concentration achieve to 2.5×106 cells/mL in the end of the culture, analyzed total lipid content so as to determine the biomass accumulation and biomass variation in different growth conditions. By ultrasonic extracting and freeze drying, the total of lipid reaches 20%(dry weight); the main content of fatty acid is C16:0,C18:0,which is the better material for biodisel production.

scholarly journals Alicyclobacillus vulcanalis sp. nov., a thermophilic, acidophilic bacterium isolated from Coso Hot Springs, California, USA

2004 ◽  
Vol 54 (5) ◽  
pp. 1703-1707 ◽  
Author(s):  
Jessica Simbahan ◽  
Rhae Drijber ◽  
Paul Blum
Keyword(s):  
Mojave Desert ◽  
Hot Springs ◽  
Lipid Membrane ◽  
Carbon Sources ◽  
Distinct Species ◽  
Rrna Gene ◽  
Alicyclobacillus Acidocaldarius ◽  
Acidophilic Bacterium ◽  
Bacterium Strain ◽  
Type Strains

A thermo-acidophilic Gram-positive bacterium, strain CsHg2T, which grows aerobically at 35–65 °C (optimum 55 °C) and at pH 2·0–6·0 (optimum 4·0), was isolated from a geothermal pool located in Coso Hot Springs in the Mojave Desert, California, USA. Phylogenetic analysis of 16S rRNA gene sequences showed that this bacterium was most closely related to the type strains of Alicyclobacillus acidocaldarius (97·8 % identity) and Alicyclobacillus sendaiensis (96·9 %), three Japanese strains denoted as UZ-1, KHA-31 and MIH 332 (96·1–96·5 %) and Alicyclobacillus genomic species FR-6 (96·3 %). Phenotypic characteristics including temperature and pH optima, G+C composition, acid production from a variety of carbon sources and sensitivity to different metal salts distinguished CsHg2T from A. acidocaldarius, A. sendaiensis and FR-6. The cell lipid membrane was composed mainly of ω-cyclohexyl fatty acid, consistent with membranes from other Alicyclobacillus species. Very low DNA–DNA hybridization values between CsHg2T and the type strains of Alicyclobacillus indicate that CsHg2T represents a distinct species. On the basis of these results, the name Alicyclobacillus vulcanalis sp. nov. is proposed for this organism. The type strain is CsHg2T (ATCC BAA-915T=DSM 16176T).

scholarly journals Halogen-based reconstruction of Russian Arctic sea ice area from the Akademii Nauk ice core (Severnaya Zemlya)

2015 ◽  
Vol 9 (4) ◽  
pp. 4407-4436 ◽  
Author(s):  
A. Spolaor ◽  
T. Opel ◽  
J. R. McConnell ◽  
O. J. Maselli ◽  
G. Spreen ◽  
...  
Keyword(s):  
Sea Ice ◽  
Ocean Circulation ◽  
Ice Core ◽  
Iodine Concentration ◽  
Arctic Sea Ice ◽  
The Arctic ◽  
Russian Arctic ◽  
Ice Surface ◽  
Spring Sea Ice ◽  
Severnaya Zemlya

Abstract. The role of sea ice in the Earth climate system is still under debate, although it is known to influence albedo, ocean circulation, and atmosphere-ocean heat and gas exchange. Here we present a reconstruction of AD 1950 to 1998 sea ice in the Laptev Sea based on the Akademii Nauk ice core (Severnaya Zemlya, Russian Arctic). The halogens bromine (Br) and iodine (I) are strongly influenced by sea ice processes. Bromine reacts with the sea ice surface in auto-catalyzing "Bromine explosion" events causing an enrichment of the Br / Na ratio and the bromine excess (Brexc) in snow compared to that in seawater. Iodine is emitted from algal communities growing under sea ice. The results suggest a connection between Brexc and spring sea ice area, as well as a connection between iodine concentration and summer sea ice area. These two halogens are therefore good candidates for extended reconstructions of past sea ice changes in the Arctic.

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