1,720,971 research outputs found
Dermea piceina (Dermateaceae): an unrecorded endophytic fungus of isolated from Abies koreana
No full textWe found an unrecorded endophytic fungus, Dermea piceina J.W. Groves, isolated from alpine conifer Abies koreana. Until now only one Dermea species, D. cerasi, has been reported in Korea. In this study, we compared morphological characteristics and DNA sequences, including internal transcribed spacer and 28S ribosomal DNA, of D. piceina isolated from A. koreana with those of related species. Here, we present morphological and molecular characters of this fungus for the first time in Korea.
Complete genome of Polaromonas vacuolata KCTC 22033T isolated from beneath Antarctic Sea ice
No full textPolaromonas vacuolata KCTC 22033T is an obligate aerobic, Gram-negative, psychrophilic and rod-shaped bacterium isolated from beneath the sea ice off the coast of the Palmer Peninsula, Anvers Islands, Antarctica. P. vacuolata is the type species of Polaromonas genus and the first example of gas vacuolate Betaproteobacteria isolated from marine habitats. Here, we report a complete genome of P. vacuolata KCTC 22033T, which consists of 3,837,686 bp (G + C content of 52.07%) with a single chromosome, 3461 protein-coding genes, 56 tRNAs and 6 rRNA operons. Genomic analysis revealed the presence of genes involved in bacterial adaptation under saline conditions, cold adaptation via the production of gas vesicles and cell adhesion proteins, and a photoheterotrophic lifestyle when challenged by starvation. Intriguingly, several of these genes were likely acquired from species outside the Polaromonas genus. The genomic information therefore describes the unique evolution and adaptation of P. vacuolata to its extraordinary habitat, i.e., beneath the Antarctic sea ice.
Hymenobacter defluvii sp. nov., isolated from wastewater of an acidic water neutralization facility
No full textA non-motile, pink-coloured and rod-shaped bacterium, designated strain POA9T, was isolated from a wastewater treatment facility, Republic of Korea. Cells were Gram-reaction-negative, aerobic, catalase-positive and oxidase-negative. The major fatty acids were C16: 1ω5c, iso-C15: 0, summed feature 3 (C16: 1ω6c and/or C16: 1ω7c) and anteiso-C15: 0. The strain contained MK-7 as the only isoprenoid quinone, phosphatidylethanolamine as the major polar lipid and sym-homospermidine as the major polyamine. The DNA G+C content was 57 mol%. A phylogenetic tree based on 16S rRNA gene sequences showed that strain POA9T forms a distinct evolutionary lineage within the radiation enclosing the members of the genus Hymenobacter, sharing the highest similarity with Hymenobacter actinosclerus CCUG 39621T (95.5% sequence similarity) followed by Hymenobacter seoulensis 16F7GT (95.5 %), Hymenobacter tibetensis XTM003T (95.4 %), Hymenobacter rutilus K2-33028T (95.4 %) and Hymenobacter psychrotolerans Tibet-IIU11T (94.9 %). A number of phenotypic characteristics distinguished strain POA9T from the related members of the genus Hymenobacter. On the basis of the evidence presented in this study, a novel species, Hymenobacter defluvii sp. Nov., is proposed for strain POA9T (=KCTC 52270T=JCM 31658T).
Hymenobacter tenuis sp. nov., isolated from wastewater of an acidic water neutralization facility
No full textA non-motile, red？pink-coloured, rod-shaped bacterium, designated strain POB6T, was isolated from a wastewater treatment facility, Republic of Korea. Cells were Gram-stain-negative, aerobic, catalase-positive and oxidase-negative. The major fatty acids were iso-C15 : 0, C16 : 1ω5c, summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) and summed feature 4 (iso-C17 : 1 I and/or anteiso-C17 : 1 B). The strain contained menaquinone MK-7 as the only isoprenoid quinone, phosphatidylethanolamine as the major polar lipid and sym-homospermidine as the major polyamine. The DNA G+C content was 61 mol%. A phylogenetic tree based on 16S rRNA gene sequences showed that strain POB6T forms a distinct evolutionary lineage within the radiation enclosing the members of the genus Hymenobacter, sharing the highest similarity with Hymenobacter rigui WPCP131T (97.5 %) followed by Hymenobacter xinjiangensis X2-1gT (97.2 %), Hymenobacter perfusus A1-12T (97.2 %) and Hymenobacter gelipurpurascens Txg-1T (97.1 %). A number of phenotypic characteristics distinguished strain POB6T from related members of the genus Hymenobacter. On the basis of the evidence presented in this study, a novel species, Hymenobacter tenuis sp. nov., is proposed, with POB6T (=KCTC 52271T=JCM 31659T) as the type strain.
Flavivirga eckloniae sp. nov. and Flavivirga aquimarina sp. nov., isolated from seaweed Ecklonia cava
No full textTwo Gram-stain-negative, non-spore-forming, rod-shaped, aerobic and yellow-coloured bacterial strains, designated strains ECD14T and EC2D5T, were isolated from a seaweed Eckloniacava. The isolates required sea salts for growth. Flexirubin-type and carotenoid pigment was produced. The 16S rRNA gene sequence similarity between the two new strains was 95.5%. Flavivirga amylovorans JC2681T was the nearest neighbour of strains ECD14T and EC2D5T with 96.5 and 96.8% 16S rRNA gene sequence similarity, respectively. The common major fatty acids and respiratory quinones were iso-C15:0, iso-C15:1 G and unknown 13.565 and menaquinone 6 (MK-6), respectively. The common major polar lipids were phosphatidylethanolamine, an unknown amino lipid and an unknown lipid. The DNA G+C contents of strains ECD14T and EC2D5T were 33 and 31？mol%, respectively. On the basis of the polyphasic characterization of the two strains, it is suggested that the two isolates represent novel species of the genus Flavivirga, for which the names Flavivirga eckloniae sp. nov. (type strain, ECD14T=KCTC 52352T=JCM 31797T) and Flavivirga aquimarina sp. nov. (type strain, EC2D5T=KCTC 52353T=JCM 31796T) are proposed.
Spirosoma taeanense sp. nov., a radiation resistant bacterium isolated from a coastal sand dune
No full textAn aerobic, Gram-negative, non-motile, non-spore-forming, rod-shaped, and pale yellow-colored bacterial strain, designated TS118T, was isolated from a sand sample obtained from a coastal sand dune after exposure to 3 kGy of gamma radiation. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolate was a member of the genus Spirosoma and most closely related to Spirosoma metallicum PR1014kT (95.1% similarity). The genome of strain TS118T is constituted by one chromosome (5,691,492 bp) and one plasmid (28,440 bp) and has a G？+？C content of 52.7%. The genome contains 4641 protein coding sequences (CDSs), 38 tRNAs, and 11 rRNAs. The predominant fatty acids of strain TS118T were C16:1 ω5c, iso-C15:0, C16:0, summed feature 3 (C16:1 ω6c and/or C16:1 ω7c), and iso-C17:0 3-OH. The major polar lipids were phosphatidylethanolamine, an unidentified amino lipid and an unidentified aminophospholipid. The main respiratory quinone was menaquinone-7 (MK-7). The novel strain showed resistance to gamma radiation with a D10 value (i.e., the dose required to reduce the bacterial population by tenfold) of 4.3 kGy. Based on the phylogenetic, physiological, and chemotaxonomic characteristics, strain TS118T represents a novel species, for which the name Spirosoma taeanense sp. nov. is proposed. The type strain is TS118T (=KCTC 72898T =JCM 34024T).
Sphingomonas limnosediminicola sp. nov. and Sphingomonas palustris sp. nov., isolated from freshwater environments
No full textTwo aerobic, Gram-stain-negative, gliding and yellow-pigmented bacteria, designated strains 03SUJ6T and WM95T were isolated from freshwater sediment of Juam reservoir and freshwater of Woopo wetland, Republic of Korea, respectively. Cells of the two strains are motile by gliding and catalase- and oxidase-positive. The 16S rRNA gene sequence similarity between 03SUJ6T and WM95T was 97.7 %, but their DNA？DNA relatedness was 55.1 %. A maximum-likelihood phylogenetic tree based on 16S rRNA gene sequences showed that 03SUJ6T and WM95T each form independent lineages within the genus Sphingomonas. 03SUJ6T was related distantly to Sphingomonas daechungensis CH15-11T (97.4% 16S rRNA gene sequence similarity), Sphingomonas ginsengisoli Gsoil 634T (97.3 %) and Sphingomonas astaxanthinifaciens DMS 22298T (97.1 %). Closest relatives of strain WM95T were S. daechungensis CH15-11T (98.2 %), Sphingomonas jaspsi DSM 18422T (97.6 %), Sphingomonas sediminicola Dae 20T (97.5 %), Sphingomonas lutea JS5T (97.4 %) and S. ginsengisoli Gsoil 634T (97.2 %). The major fatty acids of the two isolates were summed feature 8 and C16: 0. The predominant isoprenoid quinone was ubiquinone-10. The major polar lipids were diphosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and sphingoglycolipid. sym-Homospermidine was the major polyamine of the isolates. Phenotypic characteristics distinguished 03SUJ6T and WM95T from the related species of the genus Sphingomonas. On the basis of the evidence presented in this study, the novel species, Sphingomonas limnosediminicola sp. nov. and Sphingomonas palustris sp. nov. are proposed for strain 03SUJ6T (=KCTC 23331T=JCM 17543T) and strain WM95T (=KACC 18738T=JCM 31399T), respectively
Hymenobacter baengnokdamensis sp. nov., Isolated from the soil of a Crater Lake in Korea
No full textAn aerobic, Gram-stain-negative, non-motile, non-spore-forming, rod-shaped and pink-colored bacterial strain, designated BRD72T, was isolated from a crater lake (Baengnokdam) at the top of Mt. Hallasan in the Republic of Korea. Cells were catalase-positive and oxidase-negative. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that the isolate was a member of the genus Hymenobacter and most closely related to Hymenobacter marinus KJ035T (96.2% similarity). The isolate was found to produce carotenoid pigment, but not flexirubin-type pigment. The predominant fatty acids of strain BRD72T were summed feature 3 (C16:1 ω7c and/or C16:1 ω6c, 21.6%), iso-C15:0 (17.9%), anteiso-C15:0 (13.3%) and summed feature 4 (iso-C17:1 I and/or anteiso-C17:1 B, 11.3%). The major polar lipids were phosphatidylethanolamine, an unidentified amino lipid, and two unidentified aminophospholipids. The main respiratory quinone was menaquinone-7 (MK-7), and the main polyamine was homospermidine. The DNA G+C content was 59.8 mol%. Based on the phylogenetic, physiological, and chemotaxonomic characteristics, strain BRD72T represents a novel species, for which the name Hymenobacter baengnokdamensis sp. nov. is proposed. The type strain is BRD72T (=？KCTC 72649T？=？JCM 33837T).
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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