scholarly journals Thermococcus coalescens sp. nov., a cell-fusing hyperthermophilic archaeon from Suiyo Seamount

2005 ◽  
Vol 55 (6) ◽  
pp. 2507-2514 ◽  
Author(s):  
Tomohiko Kuwabara ◽  
Masaomi Minaba ◽  
Yukihiro Iwayama ◽  
Isao Inouye ◽  
Miwako Nakashima ◽  
...  

A cell-fusing hyperthermophilic archaeon was isolated from hydrothermal fluid obtained from Suiyo Seamount of the Izu-Bonin Arc. The isolate, TS1T, is an irregular coccus, usually 0·5–2 μm in diameter and motile with a polar tuft of flagella. Cells in the exponential phase of growth fused at room temperature in the presence of DNA-intercalating dye to become as large as 5 μm in diameter. Fused cells showed dark spots that moved along in the cytoplasm. Large cells with a similar appearance were also observed upon culture at 87 °C, suggesting the occurrence of similar cell fusions during growth. Transmission electron microscopy revealed that cells in the exponential phase possessed a thin and electron-lucent cell envelope that could be lost subsequently during culture. The fragile cell envelope must be related to cell fusion. The cells grew at 57–90 °C, pH 5·2–8·7 and at NaCl concentrations of 1·5–4·5 %, with the optima being 87 °C, pH 6·5 and 2·5 % NaCl. The isolate was an anaerobic chemo-organotroph that grew on either yeast extract or tryptone as the sole growth substrate. The genomic DNA G+C content was 53·9 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the isolate was closely related to Thermococcus species. However, no significant DNA–DNA hybridization was observed between genomic DNA of strain TS1T and phylogenetically related Thermococcus species. We propose that isolate TS1T represents a novel species, Thermococcus coalescens sp. nov., with the name reflecting the cell fusion activity observed in the strain. The type strain is TS1T (=JCM 12540T=DSM 16538T).

2007 ◽  
Vol 57 (3) ◽  
pp. 437-443 ◽  
Author(s):  
Tomohiko Kuwabara ◽  
Masaomi Minaba ◽  
Noriko Ogi ◽  
Masahiro Kamekura

A fast-growing and cell-fusing hyperthermophilic archaeon was isolated from a hydrothermal vent at Suiyo Seamount, Izu-Bonin Arc, Western Pacific Ocean. Strain TS2T is an irregular, motile coccus that is generally 0.7–1.5 μm in diameter and possesses a polar tuft of flagella. In the mid-exponential phase of growth, cells that appeared black under phase-contrast microscopy fused at room temperature in the presence of a DNA-intercalating dye, as previously observed in Thermococcus coalescens. Cell fusion was not observed in later growth phases. Transmission electron microscopy revealed that the cells in the mid-exponential phase had a 5 nm-thick, electron-dense cell envelope that appeared to associate loosely with the cytoplasmic membrane. As the growth stage progressed, a surface layer developed on the membrane under the envelope and the envelope eventually peeled off. These observations suggest that the surface layer prevents the fusion of cells. Cells of strain TS2T grew at 50–85 °C, pH 5.6–8.3 and at NaCl concentrations of 1.0 to 4.5 %, with optimal growth occurring at 80 °C, pH 7.0 and 3.0 % NaCl. Under optimal growth conditions, strain TS2T grew very fast with an apparent doubling time of 20 min. It is suggested that the biosynthesis of the surface layer cannot catch up with cell multiplication in the mid-exponential phase and thus cells without the surface layer are generated. Strain TS2T was an anaerobic chemo-organotroph that grew on either yeast extract or tryptone as the sole growth substrate. The genomic DNA G+C content was 54.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the isolate belongs to the genus Thermococcus. However, no significant DNA–DNA hybridization was observed between the genomic DNA of strain TS2T and phylogenetically related Thermococcus species. On the basis of this evidence, strain TS2T is proposed to represent a novel species, Thermococcus celericrescens sp. nov., a name chosen to reflect the fast growth of the strain. The type strain is TS2T (=NBRC 101555T=JCM 13640T=DSM 17994T).


2004 ◽  
Vol 54 (2) ◽  
pp. 605-608 ◽  
Author(s):  
Matthew D. Collins ◽  
Joyanto Routh ◽  
Ambujom Saraswathy ◽  
Paul A. Lawson ◽  
Peter Schumann ◽  
...  

An unknown Gram-positive, catalase-positive, facultatively anaerobic, non-spore-forming, coccus-shaped bacterium originating from sediment was characterized using phenotypic, molecular chemical and molecular phylogenetic methods. Chemical studies revealed the presence of a cell-wall murein based on ll-diaminopimelic acid (type ll-Dpm-glycine1), a complex mixture of saturated, monounsaturated and iso- and anteiso-methyl-branched, non-hydroxylated, long-chain cellular fatty acids and tetrahydrogenated menaquinones with eight isoprene units [MK-8(H4)] as the major respiratory lipoquinone. This combination of characteristics somewhat resembled members of the suborder Micrococcineae, but did not correspond to any currently described species. Comparative 16S rRNA gene sequencing confirmed that the unidentified coccus-shaped organism is a member of the Actinobacteria and represents a hitherto-unknown subline related to, albeit different from, a number of taxa including Intrasporangium, Janibacter, Terrabacter, Terracoccus and Ornithinicoccus. Based on phenotypic and phylogenetic considerations, it is proposed that the unknown bacterium originating from lake sediment be classified as a new genus and species, Arsenicicoccus bolidensis gen. nov., sp. nov. (type strain CCUG 47306T=DSM 15745T).


2006 ◽  
Vol 56 (2) ◽  
pp. 429-432 ◽  
Author(s):  
Paul A. Lawson ◽  
Matthew D. Collins ◽  
Enevold Falsen ◽  
Geoffrey Foster

Two strains of an unknown Gram-positive, catalase-negative, facultatively anaerobic, coccus-shaped bacterium, originating from a porpoise and a grey seal, were characterized using phenotypic, biochemical and molecular phylogenetic methods. Chemical studies revealed the presence of a cell-wall murein based on l-lysine (type l-lys–gly–d-Asp) and a DNA G+C content of 38 mol%. Comparative 16S rRNA gene sequencing showed that this unidentified coccus-shaped organism formed a hitherto unknown subline closely related to, albeit distinct from, a number of other catalase-negative genera which included Enterococcus, Melissococcus, Tetragenococcus and Vagococcus. Other known Gram-positive, catalase-negative taxa were more distantly related. Tree-branching considerations and sequence divergence values of >6 % with recognized taxa were indicative of this novel bacterium representing a separate genus. Based on phenotypic and phylogenetic evidence, it is proposed that this unknown bacterium, recovered from a porpoise and a grey seal, be classified as a novel genus and species, Catellicoccus marimammalium gen. nov., sp. nov. The type strain is M35/04/3T (=CCUG 49459T=CIP 108575T).


2020 ◽  
Author(s):  
Nadine T. Smit ◽  
Laura Villanueva ◽  
Darci Rush ◽  
Fausto Grassa ◽  
Caitlyn R. Witkowski ◽  
...  

Abstract. Soil bacteria rank among the most diverse groups of organisms on Earth and actively impact global processes of carbon cycling, especially in the emission of greenhouse gases like methane, CO2 and higher gaseous hydrocarbons. An abundant group of soil bacteria are the mycobacteria, which colonize various habitats due to their impermeable cell envelope that contains remarkable lipids. These bacteria have been found to be highly abundant at petroleum and gas seep areas, where they might utilize the released hydrocarbons. However, the function and the lipid biomarker inventory of these soil mycobacteria are poorly studied. Here, soils from the Fuoco di Censo seep, an everlasting fire (gas seep) in Sicily, Italy, were investigated for the presence of mycobacteria via 16S rRNA gene sequencing and fatty acid profiling. The soils contained high relative abundances (up to 34 % of reads assigned) of mycobacteria, phylogenetically close to the Mycobacterium simiae complex and more distant to the well-studied M. tuberculosis and hydrocarbon-utilizing M. paraffinicum. The soils showed decreasing abundances of mycocerosic acids (MAs), fatty acids unique for mycobacteria, with increasing distance from the seep. The major MAs at this seep were tentatively identified as 2,4,6,8-tetramethyl tetracosanoic acid and 2,4,6,8,10-pentamethyl hexacosanoic acid. Unusual MAs with mid-chain methyl branches at positions C-12 and C-16 (i.e. 2,12-dimethyl eicosanoic acid and 2,4,6,8,16-pentamethyl tetracosanoic acid) were also present. The molecular structures of the Censo MAs are different from those of the well-studied mycobacteria like M. tuberculosis or M. bovis and have relatively 13C-depleted values (−38 to −48 ‰), suggesting a direct or indirect utilization of the released seep gases like methane or ethane. The structurally unique MAs in combination with their depleted δ13C values identified at the Censo seep offer a new tool to study the role of soil mycobacteria as hydrocarbon gas consumers in the carbon cycle.


2005 ◽  
Vol 55 (4) ◽  
pp. 1693-1696 ◽  
Author(s):  
Matthew D. Collins ◽  
Anna Wiernik ◽  
Enevold Falsen ◽  
Paul A. Lawson

A novel Gram-positive, aerobic, catalase-negative, coccus-shaped organism originating from tobacco was characterized using phenotypic and molecular taxonomic methods. The organism contained a cell wall murein based on l-lysine (variation A4α, type l-lysine–l-glutamic acid), synthesized long-chain cellular fatty acids of the straight-chain saturated and monounsaturated types (with C16 : 1 ω9, C16 : 0 and C18 : 1 ω9 predominating) and possessed a DNA G+C content of 46 mol%. Based on morphological, biochemical and chemical characteristics, the coccus-shaped organism did not conform to any presently recognized taxon. Comparative 16S rRNA gene sequencing studies confirmed the distinctiveness of the unknown coccus, with the bacterium displaying sequence divergence values of greater than 7 % with other recognized Gram-positive taxa. Treeing analysis reinforced its distinctiveness, with the unidentified organism forming a relatively long subline branching at the periphery of an rRNA gene sequence cluster which encompasses the genera Alloiococcus, Allofustis, Alkalibacterium, Atopostipes, Dolosigranulum and Marinilactibacillus. Based on phenotypic and molecular phylogenetic evidence, it is proposed that the unknown organism from tobacco be classified as a new genus and species, Atopococcus tabaci gen. nov., sp. nov. The type strain of Atopococcus tabaci is CCUG 48253T (=CIP 108502T).


2011 ◽  
Vol 61 (10) ◽  
pp. 2503-2507 ◽  
Author(s):  
Satoru Shimizu ◽  
Rahul Upadhye ◽  
Yoji Ishijima ◽  
Takeshi Naganuma

A methanogenic organism, designated strain HB-1T, from the domain Archaea was isolated from groundwater sampled from a subsurface Miocene formation located in Horonobe, Hokkaido, Japan. The strain grew on methanol, dimethylamine, trimethylamine, dimethylsulfide and acetate but not on monomethylamine, H2/CO2, formate, 2-propanol, 2-butanol or cyclopentanol. Cells were Gram-reaction-negative, non-motile, irregular cocci that were 1.4–2.9 µm in diameter and occurred singly or in pairs. The strain grew at 20–42 °C (optimum 37 °C), at pH 6.0–7.75 (optimum pH 7.0–7.25) and in 0–0.35 M NaCl (optimum 0.1 M). The G+C content of the genomic DNA was 41.4 mol%. 16S rRNA gene sequencing revealed that the strain was a member of the genus Methanosarcina but that it clearly differed from all recognized species of this genus (93.1–97.9 % sequence similarity). The phenotypic and phylogenetic features of strain HB-1T indicate that it represents a novel species of the genus Methanosarcina, for which the name Methanosarcina horonobensis sp. nov. is proposed. The type strain is HB-1T ( = DSM 21571T  = JCM 15518T  = NBRC 102577T).


2021 ◽  
Vol 18 (4) ◽  
pp. 1463-1479
Author(s):  
Nadine T. Smit ◽  
Laura Villanueva ◽  
Darci Rush ◽  
Fausto Grassa ◽  
Caitlyn R. Witkowski ◽  
...  

Abstract. Soil bacteria rank among the most diverse groups of organisms on Earth and actively impact global processes of carbon cycling, especially in the emission of greenhouse gases like methane, CO2 and higher gaseous hydrocarbons. An abundant group of soil bacteria are the mycobacteria, which colonize various terrestrial, marine and anthropogenic environments due to their impermeable cell envelope that contains remarkable lipids. These bacteria have been found to be highly abundant at petroleum and gas seep areas, where they might utilize the released hydrocarbons. However, the function and the lipid biomarker inventory of these soil mycobacteria are poorly studied. Here, soils from the Fuoco di Censo seep, an everlasting fire (gas seep) in Sicily, Italy, were investigated for the presence of mycobacteria via 16S rRNA gene sequencing and fatty acid profiling. The soils contained high relative abundances (up to 34 % of reads assigned) of mycobacteria, phylogenetically close to the Mycobacterium simiae complex and more distant from the well-studied M. tuberculosis and hydrocarbon-utilizing M. paraffinicum. The soils showed decreasing abundances of mycocerosic acids (MAs), fatty acids unique for mycobacteria, with increasing distance from the seep. The major MAs at this seep were tentatively identified as 2,4,6,8-tetramethyl tetracosanoic acid and 2,4,6,8,10-pentamethyl hexacosanoic acid. Unusual MAs with mid-chain methyl branches at positions C-12 and C-16 (i.e., 2,12-dimethyl eicosanoic acid and 2,4,6,8,16-pentamethyl tetracosanoic acid) were also present. The molecular structures of the Fuoco di Censo MAs are different from those of the well-studied mycobacteria like M. tuberculosis or M. bovis and have relatively δ13C-depleted values (−38 ‰ to −48 ‰), suggesting a direct or indirect utilization of the released seep gases like methane or ethane. The structurally unique MAs in combination with their depleted δ13C values identified at the Fuoco di Censo seep offer a new tool to study the role of soil mycobacteria as hydrocarbon gas consumers in the carbon cycle.


2019 ◽  
Vol 13 (1) ◽  
pp. 90-101
Author(s):  
Sanju Kumari ◽  
Utkarshini Sharma ◽  
Rohit Krishna ◽  
Kanak Sinha ◽  
Santosh Kumar

Background: Cellulolysis is of considerable economic importance in laundry detergents, textile and pulp and paper industries and in fermentation of biomass into biofuels. Objective: The aim was to screen cellulase producing actinobacteria from the fruit orchard because of its requirement in several chemical reactions. Methods: Strains of actinobacteria were isolated on Sabouraud’s agar medium. Similarities in cultural and biochemical characterization by growing the strains on ISP medium and dissimilarities among them perpetuated to recognise nine groups of actinobacteria. Cellulase activity was measured by the diameter of clear zone around colonies on CMC agar and the amount of reducing sugar liberated from carboxymethyl cellulose in the supernatant of the CMC broth. Further, 16S rRNA gene sequencing and molecular characterization were placed before NCBI for obtaining recognition with accession numbers. Results: Prominent clear zones on spraying Congo Red were found around the cultures of strains of three groups SK703, SK706, SK708 on CMC agar plates. The enzyme assay for carboxymethylcellulase displayed extra cellulase activity in broth: 0.14, 0.82 and 0.66 µmol mL-1 min-1, respectively at optimum conditions of 35°C, pH 7.3 and 96 h of incubation. However, the specific cellulase activities per 1 mg of protein did not differ that way. It was 1.55, 1.71 and 1.83 μmol mL-1 min-1. The growing mycelia possessed short compact chains of 10-20 conidia on aerial branches. These morphological and biochemical characteristics, followed by their verification by Bergey’s Manual, categorically allowed the strains to be placed under actinobacteria. Further, 16S rRNA gene sequencing, molecular characterization and their evolutionary relationship through phylogenetics also confirmed the putative cellulase producing isolates of SK706 and SK708 subgroups to be the strains of Streptomyces. These strains on getting NCBI recognition were christened as Streptomyces glaucescens strain SK91L (KF527284) and Streptomyces rochei strain SK78L (KF515951), respectively. Conclusion: Conclusive evidence on the basis of different parameters established the presence of cellulase producing actinobacteria in the litchi orchard which can convert cellulose into fermentable sugar.


Life ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 254
Author(s):  
Ying Wang ◽  
Jianqing Zhu ◽  
Jie Fang ◽  
Li Shen ◽  
Shuojia Ma ◽  
...  

We characterized the gut microbial composition and relative abundance of gut bacteria in the larvae and adults of Pieris canidia by 16S rRNA gene sequencing. The gut microbiota structure was similar across the life stages and sexes. The comparative functional analysis on P. canidia bacterial communities with PICRUSt showed the enrichment of several pathways including those for energy metabolism, immune system, digestive system, xenobiotics biodegradation, transport, cell growth and death. The parameters often used as a proxy of insect fitness (development time, pupation rate, emergence rate, adult survival rate and weight of 5th instars larvae) showed a significant difference between treatment group and untreated group and point to potential fitness advantages with the gut microbiomes in P. canidia. These data provide an overall view of the bacterial community across the life stages and sexes in P. canidia.


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