| nucleic acid homology studies among candida albicans, syringospora albicans and leucosporidium species. | deoxyribonucleic acid-ribonucleic acid (dna-rna) hybridization technique was used to investigate nucleic acid homologies among acid candida albicans, syringospora albicans and the leucosporidium species (l. nivalis, l. capsuligenum, l. frigidum, l. gelidum, l. antarcticum). the nucleic acid homology between c. albicans, s. albicans and the leucosporidium species was very low (ranging from about 7-11% for c. albicans and 8-12-5% for s. albicans), indicating the unrelatedness of c. albicans to the ... | 1975 | 1102862 |
| [paramonostomum antarcticum n. sp. (trematoda: notocotylidae) and observations on the development of larvae in the antarctic]. | | 1968 | 4906486 |
| polyamine distribution profiles in the eighteen genera phylogenetically located within the flavobacterium-flexibacter-cytophaga complex. | cellular polyamines of eighteen genera belonging to the flavobacterium-flexibacter-cytophaga complex were analysed by ion exchange liquid chromatography. homospermidine was the major polyamine in the genera bergeyella, riemerella, ornithobacterium, weeksella, capnocytophaga, polaribacter and psychroflexus belonging to the family flavobacteriaceae. in the family spirosomaceae, runella, spirosoma and flectobacillus species contained spermidine whereas cyclobacterium species contained homospermidin ... | 2001 | 11491527 |
| phylogenetic composition of bacterioplankton assemblages from the arctic ocean. | we analyzed the phylogenetic composition of bacterioplankton assemblages in 11 arctic ocean samples collected over three seasons (winter-spring 1995, summer 1996, and summer-fall 1997) by sequencing cloned fragments of 16s rrna genes. the sequencing effort was directed by denaturing gradient gel electrophoresis (dgge) screening of samples and the clone libraries. sequences of 88 clones fell into seven major lineages of the domain bacteria: alpha(36%)-, gamma(32%)-, delta(14%)-, and epsilon(1%)-p ... | 2002 | 11823184 |
| chemical characterization of exopolysaccharides from antarctic marine bacteria. | exopolysaccharides (eps) may have an important role in the antarctic marine environment, possibly acting as ligands for trace metal nutrients such as iron or providing cryoprotection for growth at low temperature and high salinity. ten bacterial strains, isolated from southern ocean particulate material or from sea ice, were characterized. whole cell fatty acid profiles and 16s rrna gene sequences showed that the isolates included representatives of the genera pseudoalteromonas, shewanella, pola ... | 2005 | 16052372 |
| properties of cold-adapted subtilisine-like proteinase of endemic yeast leucosporidium antarcticum. | an extracellular serine proteinase from psychrophilic marine antarctic yeast l. antarcticum has been purified to homogeneity and characterized. the enzyme specificity, which resembles both chymotrypsin and subtilisin, as well as kinetic (topt of 25 degrees c, activity up to -20 degrees c, phoptbztyroet of 8.0-8.5), and thermodynamic properties conferring cold-adaptation of the proteinase, were determined the comparison of n-terminal sequence of 35 amino acid residues with known sequences of seri ... | 2001 | 15954613 |
| flavobacterium antarcticum sp. nov., a novel psychrotolerant bacterium isolated from the antarctic. | a yellow-pigmented, gram-negative and aerobic bacterial strain, designated at1026(t), was isolated from a terrestrial sample from the antarctic. results of 16s rrna gene sequence analysis indicated that the antarctic isolate belonged to the genus flavobacterium, with the highest sequence similarity to flavobacterium tegetincola (96.4 %). cells were non-motile, non-gliding and psychrotolerant, with optimum and maximum temperatures of about 20 and 25 degrees c. flexirubins were absent. the major i ... | 2005 | 15774636 |
| the cost of foraging by a marine predator, the weddell seal leptonychotes weddellii: pricing by the stroke. | foraging by mammals is a complex suite of behaviors that can entail high energetic costs associated with supporting basal metabolism, locomotion and the digestion of prey. to determine the contribution of these various costs in a free-ranging marine mammal, we measured the post-dive oxygen consumption of adult weddell seals (n=9) performing foraging and non-foraging dives from an isolated ice hole in mcmurdo sound, antarctica. dives were classified according to behavior as monitored by an attach ... | 2004 | 14766956 |
| structural analysis of sphingophospholipids derived from sphingobacterium spiritivorum, the type species of genus sphingobacterium. | the unique feature of the genus sphingobacterium is the presence of sphingophospholipids and ceramides, besides diacylglycerophospholipids. as major cellular lipid components, five kinds of sphingophospholipids were purified from sphingobacterium spiritivorum atcc 33861(t), the type species of genus sphingobacterium. they were identified as ceramide phosphorylethanolamines (cerpe-1 and cerpe-2), ceramide phosphoryl-myo-inositols (cerpi-1 and cerpi-2), and ceramide phosphorylmannose (cerpm-1). th ... | 2003 | 14729071 |
| diversity and structure of bacterial communities in arctic versus antarctic pack ice. | a comprehensive assessment of bacterial diversity and community composition in arctic and antarctic pack ice was conducted through cultivation and cultivation-independent molecular techniques. we sequenced 16s rrna genes from 115 and 87 pure cultures of bacteria isolated from arctic and antarctic pack ice, respectively. most of the 33 arctic phylotypes were >97% identical to previously described antarctic species or to our own antarctic isolates. at both poles, the alpha- and gamma-proteobacteri ... | 2003 | 14602620 |
| a cold-adapted extracellular serine proteinase of the yeast leucosporidium antarcticum. | an extracellular serine proteinase, lap2, from the psychrophilic antarctic yeast leucosporidium antarcticum 171 was purified to homogeneity and characterized. the enzyme is a glycoprotein with a molecular mass of 34.4 kda and an isoelectric point of ph 5.62. the proteinase is halotolerant, and its activity and stability are dependent neither on ca(2+) nor on other metal ions. lap2 is a true psychrophilic enzyme because of low optimal temperature (25 degrees c), poor thermal stability, relatively ... | 2003 | 12845553 |
| exiguobacterium undae sp. nov. and exiguobacterium antarcticum sp. nov. | four orange-pigmented strains from pond water (l1-l4) have been subjected to polyphasic taxonomic analyses. on the basis of ribotype analysis and fourier-transform infrared spectroscopy, these strains form a genomically highly related group. 16s rdna sequence analysis revealed 98.8% similarity between the 16s rdna sequences of strains l2t and h2t, isolated previously from a microbial mat from lake fryxell, antarctica. dna-dna reassociation values indicated the presence of two genomic clusters. w ... | 2002 | 12148624 |
| phylogenetic diversity of numerically important arctic sea-ice bacteria cultured at subzero temperature. | heterotrophic bacteria in sea ice play a key role in carbon cycling, but little is known about the predominant players at the phylogenetic level. in a study of both algal bands and clear ice habitats within summertime arctic pack ice from the chukchi sea, we determined the abundance of total bacteria and actively respiring cells in melted ice samples using epifluorescence microscopy and the stains 4', 6'-diamidino-2-phenylindole 2hcl (dapi) and 5-cyano-2,3-ditolyl tetrazolium chloride (ctc), res ... | 2002 | 12037610 |
| poles apart: biodiversity and biogeography of sea ice bacteria. | this review introduces the subjects of bacterial biodiversity and biogeography. studies of biogeography are important for understanding biodiversity, the occurrence of threatened species, and the ecological role of free-living and symbiotic prokaryotes. a set of postulates is proposed for biogeography as a guide to determining whether prokaryotes are "cosmopolitan" (found in more than one geographic location on earth) or candidate endemic species. the term "geovar" is coined to define a geograph ... | 1999 | 10547690 |
| heat shock response in psychrophilic and psychrotrophic yeast from antarctica. | the response to heat stress in six yeast species isolated from antarctica was examined. the yeast were classified into two groups: one psychrophilic, with a maximum growth temperature of 20 degrees c, and the other psychrotrophic, capable of growth at temperatures above 20 degrees c. in addition to species--specific heat shock prote in (hsp) profiles, a heat shock (15 degrees c-25 degrees c for 3 h) induced the synthesis of a 110-kda protein common to the psychrophiles, mrakia stokesii, m. frigi ... | 1998 | 9676242 |
| polaribacter gen. nov., with three new species, p. irgensii sp. nov., p. franzmannii sp. nov. and p. filamentus sp. nov., gas vacuolate polar marine bacteria of the cytophaga-flavobacterium-bacteroides group and reclassification of 'flectobacillus glomeratus' as polaribacter glomeratus comb. nov. | several psychrophilic, gas vacuolate strains of the cytophage-flavobacterium-bacteroides (cfb) phylogenetic group were isolated from sea ice and water from the arctic and the antarctic. the closest taxonomically defined species by 16s rrna sequence analysis is 'flectobacillus glomeratus'. however, 'flc. glomeratus' is phylogenetically distant from the flectobacillus type species, flc. major. on the basis of phenotypic, genotypic and 16s rrna sequence analyses we propose a new genus, polaribacter ... | 1998 | 9542092 |
| the hemoglobin system of pleuragramma antarcticum: correlation of hematological and biochemical adaptations with life style. | the hematological properties and the oxygen-transport system of the antarctic fish pleuragramma antarcticum were investigated. most blood parameters are at the lower end of the range of values known for red-blooded antarctic fish, suggesting a link with the sluggish mode of life of this species. p. antarcticum is the only species of the family nototheniidae and of the suborder notothenioidei having three major hemoglobins, which were isolated and fully characterized. the complete amino acid sequ ... | 1997 | 9505418 |
| the unique hemoglobin system of pleuragramma antarcticum, an antarctic migratory teleost. structure and function of the three components. | pleuragramma antarcticum (suborder notothenioidei, family nototheniidae) is the most abundant fish in the antarctic shelf. this pelagic species has a circum-antarctic distribution and is characterized by spawning migration. this species displays the highest multiplicity of major hemoglobins (three); the other notothenioids have a single one (except one species, having two) with relatively low oxygen affinity regulated by ph and organophosphates. the hemoglobins of p. antarcticum display strong b ... | 1996 | 8798605 |
| [antifreeze glycoproteins in fishes: structure, mode of action and possible applications]. | two types of antifreezes have been isolated from polar and northern temperate fishes so far. they are either glycopeptides or peptides. whereas these proteins have only a very small effect on the melting temperature of ice, the temperature of these fish can fall to nearly 1 degree below the melting point before ice crystals grow. this phenomenon is called thermal hysteresis, in contrast to the normal colligative effect of solutes. all antarctic notothenioids (perches) investigated so far have th ... | 1996 | 8720947 |
| effect of supplementation of university of wisconsin solution with glycoproteins from psychrophilic strains of yeast on hypothermic liver storage of rats. | extracellular yeast glycoproteins (yg) produced by rhodosporidium toruloides have been shown to increase the survival rate of different yeast species after storage in liquid nitrogen. the purpose of this study was to investigate the effect of yg on cold-stored rat livers. water-soluble yg produced either by phaffia rhodozyma (g3) or by leucosporidium antarcticum (g4) were added to a modified university of wisconsin solution (muw) and used for cold storage (1 degree c) of isolated livers. the fun ... | 1996 | 8689892 |
| unusual brain nucleus in the diencephalon of a perciform (nototheniid) fish from antarctica. | this cytoarchitectonic analysis on the rostral diencephalon of antarctic perciform fishes confirms the previously established perciform diencephalic body plan. however, it resulted in the detection of an additional, large and conspicuous brain nucleus (unusual nucleus, un) in the antarctic nototheniid pleuragramma antarcticum. this nucleus has not been seen before in any other perciform. the un is probably homologous to a visually related nucleus (named nucleus rostrolateralis and lateral entope ... | 1995 | 8595182 |
| diversification of brain morphology in antarctic notothenioid fishes: basic descriptions and ecological considerations. | the notothenioidei, a perciform suborder of 120 species, dominates the ichthyofauna of the southern ocean around antarctica. unlike most teleost groups, notothenioids have undergone a corresponding ecological and phyletic diversification and therefore provide an excellent opportunity to study the divergence of the nervous system in an unusual environment. our goal is to evaluate notothenioid brain variation in light of this diversification. to provide a baseline morphology, we examine the gross ... | 1995 | 7869385 |
| antifreeze glycopeptides of the high-antarctic silverfish pleuragramma antarcticum (notothenioidei). | antifreeze glycopeptides (afgp) have been isolated from the fully pelagic high-antarctic silverfish pleuragramma antarcticum of the suborder notothenioidei (perciformes). the fishes were caught during the prv polarstern expedition epos iii (jan-mar, 1989) in the eastern and southeastern weddell sea. glycoconjugate and amino acid analysis of antifreeze glycopeptides (afgp) indicate that the glycopeptide structure is identical to the polymers of h2n[ala-ala(beta-galactosyl(1-->3)-alpha-n- acetylga ... | 1995 | 7656179 |
| [paramonostomum antarcticum (trematoda, notocotylidae) in larus dominicanus from south shetlands (antarctica)]. | paramonostomum antarcticum graefe, 1968 from the rectum of blackbacked gull from king george as island (south shetlands, antarctica) is described. as a result of that larus dominicanus is presented the new host of this trematode. the morphology is compared with the original description of p. signiense jones & williams, 1969. the relations between the two possibly identical antarctic species are discussed. it is proposed to invalidate the subgenus paramonostomoides yamaguti, 1971. | 1982 | 7149331 |
| [a nematode parasite of the penguin spheniscus magellanicus (forster) (ascaridoidea, anisakidae)]. | the nematodes were collected from the penguin spheniscus magellanicus (forster) (sphenisciformes). a study from the main species of contracaecum that occur in penguins and piscivorous birds from the south hemisphere is made, more specifically the c. eudyptulae johnston & mawson, 1942a, c. eudyptes johnston & mawson, 1953, c. heardi mawson, 1953, c. antarcticum johnston, 1938, c. prevosti tchéprakoff, 1966, c. spiculigerum (rudolphi, 1809), c. osculatum (rudolphi, 1802), c. scotti (leiper & atkin ... | 1984 | 6543564 |
| freezing resistance of antifreeze-deficient larval antarctic fish. | antarctic notothenioids, along with many other polar marine fishes, have evolved biological antifreeze proteins (afps) to survive in their icy environments. the larvae of antarctic notothenioid fish hatch into the same frigid environment inhabited by the adults, suggesting that they must also be protected by sufficient afps, but this has never been verified. we have determined the contribution of afps to the freezing resistance of the larvae of three species: gymnodraco acuticeps, pagothenia bor ... | 2006 | 16424091 |
| telonema antarcticum sp. nov., a common marine phagotrophic flagellate. | telonema is a widely distributed group of phagotrophic flagellates with two known members. in this study, the structural identity and molecular phylogeny of telonema antarcticum was investigated and a valid description is proposed. molecular phylogeny was studied using small-subunit rrna (ssu rrna) gene sequences. the pear-shaped cell had two subequal flagella that emerged laterally on the truncated antapical tail. one flagellum had tripartite hairs. the cell was naked, but had subsurface vesicl ... | 2005 | 16280533 |
| polaribacter butkevichii sp. nov., a novel marine mesophilic bacterium of the family flavobacteriaceae. | a novel heterotrophic, yellow pigmented, aerobic, gram-negative, nonmotile, oxidase- and catalase-positive bacterium kmm 3,938(t) was isolated from sea water collected in the sea of japan, russia. the strain grew at mesophilic temperature range, and required the presence of nacl for growth. 16s rrna gene sequence analysis revealed that strain kmm 3,938(t) is a member of the family flavobacteriaceae. the predominant fatty acids were c13:0 iso, c14:0 iso, c15:0 iso, c15:0, c15:1delta6, 3oh-c15:0:3 ... | 2005 | 16235024 |
| antioxidant efficiency in early life stages of the antarctic silverfish, pleuragramma antarcticum: responsiveness to pro-oxidant conditions of platelet ice and chemical exposure. | the antarctic silverfish pleuragramma antarcticum is a key organism in the ecology of southern ocean. eggs with fully developed yolk-sac embryos and newly hatched larvae have been recently observed to occur in the platelet ice accumulating below the sea-ice layer. this environment has strong pro-oxidant characteristics at the beginning of austral spring, when the rapid growth of algal ice communities, the massive release of nutrients and the photoactivation of dissolved organic carbon and nitrat ... | 2005 | 16087253 |
| characterization of exiguobacterium isolates from the siberian permafrost. description of exiguobacterium sibiricum sp. nov. | three gram-positive bacterial strains, 7-3, 255-15 and 190-11, previously isolated from siberian permafrost, were characterized and taxonomically classified. these microorganisms are rod-shaped, facultative aerobic, motile with peritrichous flagella and their growth ranges are from -2.5 to 40 degrees c. the chemotaxonomic markers indicated that the three strains belong to the genus exiguobacterium. their peptidoglycan type was a3alpha l-lys-gly. the predominant menaquinone detected in all three ... | 2006 | 16489412 |
| lutibacter litoralis gen. nov., sp. nov., a marine bacterium of the family flavobacteriaceae isolated from tidal flat sediment. | a rod-shaped marine bacterium, designated strain cl-tf09t, isolated from a tidal flat in ganghwa, korea, was characterized based on its physiological and biochemical features, fatty acid profile and phylogenetic position. 16s rrna gene sequence analysis revealed a clear affiliation with the family flavobacteriaceae. strain cl-tf09t showed the closest phylogenetic relationship with the genera tenacibaculum and polaribacter; sequence similarities between cl-tf09t and the type strains of tenacibacu ... | 2006 | 16585692 |
| polaribacter dokdonensis sp. nov., isolated from seawater. | a gram-negative, non-motile, non-spore-forming, slightly halophilic bacterial strain, dsw-5(t), was isolated from seawater off dokdo, korea, and subjected to a polyphasic taxonomic study. it grew optimally at 25-28 degrees c and in the presence of 2 % (w/v) nacl. strain dsw-5(t) contained mk-6 as the predominant menaquinone and iso-c(15 : 0), iso-c(15 : 1) and iso-c(15 : 0) 3-oh as the major fatty acids. the major polar lipids detected were phosphatidylethanolamine, three unidentified phospholip ... | 2006 | 16738100 |
| competition among penguins and cetaceans reveals trophic cascades in the western ross sea, antarctica. | an apparent trophic cascade that appears during summer in the western ross sea, antarctica, explains why the antarctic silverfish (pleuragramma antarcticum) there becomes cannibalistic; its principal prey, crystal krill (euphausia crystallorophias) becomes scarce; and the diatom community is minimally grazed compared to adjacent areas. the krill is the major grazer of diatoms. on the basis of fieldwork at ross island, we suggest that the cascade results from foraging by unusually numerous adélie ... | 2006 | 16937647 |
| guidus n. gen. (cestoda: tetraphyllidea), with description of a new species and emendation of the generic diagnosis of marsupiobothrium. | guidus n. gen. (cestoda, tetraphyllidea) is proposed for 3 cestode species from skates (bathyraja spp.: rajiformes, rajidae). members of guidus differ from those of all other phyllobothriid genera in possessing 4 sessile and conspicuously muscular, saclike bothridia; a bothridial aperture toward anterior end of scolex, and perpendicular to scolex axis; aperture surrounded by a continuous sphincter of circular muscles, and 1 marginal accessory sucker. a new species, guidus argentinense n. sp., is ... | 2006 | 17001785 |
| predominance of roseobacter, sulfitobacter, glaciecola and psychrobacter in seawater collected off ushuaia, argentina, sub-antarctica. | bacterial diversity in sub-antarctic seawater, collected off ushuaia, argentina, was examined using a culture independent approach. the composition of the 16s rrna gene libraries from seawater and seawater contaminated with the water soluble fraction of crude oil was statistically different (p value 0.001). in both libraries, clones representing the alphaproteobacteria, gammaproteobacteria, the cytophaga-flavobacterium-bacteroidetes group and unculturable bacteria were dominant. clones associate ... | 2007 | 17026513 |
| delta13c and delta15n shifts in benthic invertebrates exposed to sewage from mcmurdo station, antarctica. | in an effort to identify biomonitors for contamination of antarctic marine benthos by sewage, this study determines whether the us antarctic program's mcmurdo station produces a benthic sewage footprint and whether resident megafauna are assimilating sewage-derived material. we identified strong c and n isotopic gradients in benthic sediment as a function of downstream distance from mcmurdo station's point-source sewage addition. sediment c and n isotope ratios approached marine background level ... | 2006 | 17046028 |
| demographic history and population structure of the antarctic silverfish pleuragramma antarcticum. | the antarctic silverfish pleuragramma antarcticum (nototheniidae) is the most abundant pelagic fish inhabiting antarctic waters. in this study we investigated, through partial sequencing of the d-loop mitochondrial region, samples collected at four different locations in the southern ocean, three in the atlantic and one in the pacific sector. sampling was replicated in two different years at two locations. sequence analysis showed a remarkably high polymorphism, with 110 haplotypes over the 256 ... | 2006 | 17107479 |
| exiguobacterium indicum sp. nov., a psychrophilic bacterium from the hamta glacier of the himalayan mountain ranges of india. | strain hhs 31(t), a gram-positive, motile, rod-shaped, non-spore-forming, alkaliphilic bacterium, was isolated from the melt water of a glacier. phenotypic and chemotaxonomic characteristics indicate that strain hhs 31(t) is related to species of the genus exiguobacterium. the 16s rrna gene sequence similarities between hhs 31(t) and strains of known species confirm that it is closely related to members of the genus exiguobacterium (93-99 %) and that it exhibits >97 % similarity with exiguobacte ... | 2006 | 17158975 |
| analysis of environmental 18s ribosomal rna sequences reveals unknown diversity of the cosmopolitan phylum telonemia. | telonemia has recently been described as a new eukaryotic phylum with uncertain evolutionary origin. so far, only two telonemia species, telonema subtilis and telonema antarcticum, have been described, but there are substantial variations in size and morphology among telonema isolates and field observations, indicating a hidden diversity of telonemia-like species and populations. in this study, we investigated the diversity and the global distribution of this group by analyzing 18s rdna sequence ... | 2007 | 17196879 |
| bacterial community structure associated with the antarctic soft coral, alcyonium antarcticum. | the structure and composition of microbial communities inhabiting the soft coral alcyonium antarcticum were investigated across three differentially contaminated sites within mcmurdo sound, antarctica. diverse microbial communities were revealed at all sites using culture-based analysis, denaturing gradient gel electrophoresis (dgge), 16s rrna gene clone-library analysis, and fish. phylogenetic analysis of isolates and retrieved sequences demonstrated close affiliation with known psychrophiles f ... | 2007 | 17233746 |
| effect of low temperature and culture media on the growth and freeze-thawing tolerance of exiguobacterium strains. | bacteria of the genus exiguobacterium have been repeatedly isolated from ancient permafrost sediments of the kolyma lowland of northeast eurasia. here we report that the siberian permafrost isolates exiguobacterium sibiricum 255-15, e. sibiricum 7-3, exiguobacterium undae 190-11 and e. sp. 5138, as well as exiguobacterium antarcticum dsm 14480, isolated from a microbial mat sample of lake fryxell (mcmurdo dry valleys, antarctica), were able to grow at temperatures ranging from -6 to 40 degrees c ... | 2007 | 17382311 |
| trophic interactions within the ross sea continental shelf ecosystem. | the continental shelf of the ross sea is one of the antarctic's most intensively studied regions. we review the available data on the region's physical characteristics (currents and ice concentrations) and their spatial variations, as well as components of the neritic food web, including lower and middle levels (phytoplankton, zooplankton, krill, fishes), the upper trophic levels (seals, penguins, pelagic birds, whales) and benthic fauna. a hypothetical food web is presented. biotic interactions ... | 2007 | 17405209 |
| diversity and genomics of antarctic marine micro-organisms. | marine bacterioplanktons are thought to play a vital role in southern ocean ecology and ecosystem function, as they do in other ocean systems. however, our understanding of phylogenetic diversity, genome-enabled capabilities and specific adaptations to this persistently cold environment is limited. bacterioplankton community composition shifts significantly over the annual cycle as sea ice melts and phytoplankton bloom. microbial diversity in sea ice is better known than that of the plankton, wh ... | 2007 | 17553778 |
| lutimonas vermicola gen. nov., sp. nov., a member of the family flavobacteriaceae isolated from the marine polychaete periserrula leucophryna. | a gram-negative, yellow-coloured, non-motile, chemoheterotrophic, strictly aerobic, rod-shaped bacterium, designated imcc1616(t), was isolated from the marine polychaete periserrula leucophryna inhabiting tidal flat sediment of the yellow sea, and characterized by a polyphasic approach. the temperature, ph and nacl ranges for growth were 3-37 degrees c, ph 5.0-11.0 and 0.5-7.5 %. based on 16s rrna gene sequence similarity analyses, the strain was most closely related to members of the genera lut ... | 2007 | 17684236 |
| brain and sense organ anatomy and histology of the falkland islands mullet, eleginops maclovinus (eleginopidae), the sister group of the antarctic notothenioid fishes (perciformes: notothenioidei). | the perciform notothenioid fish eleginops maclovinus, representing the monotypic family eleginopidae, has a non-antarctic distribution in the falkland islands and southern south america. it is the sister group of the five families and 103 species of antarctic notothenioids that dominate the cold shelf waters of antarctica. eleginops is the ideal subject for documenting the ancestral morphology of nervous and sensory systems that have not had historical exposure to the unusual antarctic thermal a ... | 2008 | 17902153 |
| actimicrobium antarcticum gen. nov., sp. nov., of the family oxalobacteraceae, isolated from antarctic coastal seawater. | a gram-negative, non-motile, catalase- and oxidase- positive, strictly aerobic, and short rod-shaped bacterium that was designated strain kopri 25157(t) was isolated from coastal seawater sample in antarctica. the temperature and ph ranges for growth on r2a agar were 10-20┬░c, and 5.0-10.0, respectively. phylogenetic analyses of the 16s rrna gene sequence of strain kopri 25157(t) showed it to belong to the family oxalobacteraceae of the class betaproteobacteria, and it formed a distinct clade fr ... | 2011 | 21674165 |
| robiginitomaculum antarcticum gen. nov., sp. nov., a member of the family hyphomonadaceae, from antarctic seawater. | a seawater bacterium, designated imcc3195t, was isolated from the antarctic coast. cells of the novel strain were gram-negative, rusty-coloured, strictly aerobic, chemoheterotrophic, non-budding and non-motile rods or vibrioids that possessed a thin prostheca. based on 16s rrna gene sequence comparisons, the novel strain was most closely related to the genera hyphomonas (89.4-90.9%), maricaulis (90.1-90.4%), hirschia (89.0%) and oceanicaulis (87.9%) of the family hyphomonadaceae. phylogenetic an ... | 2007 | 17978224 |
| actibacter sediminis gen. nov., sp. nov., a marine bacterium of the family flavobacteriaceae isolated from tidal flat sediment. | a yellow-pigmented, gram-negative, aerobic bacterial strain comprising rod-shaped cells devoid of flagellar and gliding motility, designated strain jc2129(t), was isolated from tidal flat sediment of dongmak on ganghwa island, south korea. results from a 16s rrna gene sequence analysis indicated that the isolate belonged to the family flavobacteriaceae; the highest level of nucleotide sequence similarity (91.9%) occurred with polaribacter dokdonensis dsw-5(t). the predominant cellular fatty acid ... | 2008 | 18175699 |
| metatranscriptomic analysis of autonomously collected and preserved marine bacterioplankton. | planktonic microbial activity and community structure is dynamic, and can change dramatically on time scales of hours to days. yet for logistical reasons, this temporal scale is typically under-sampled in the marine environment. in order to facilitate higher-resolution, long-term observation of microbial diversity and activity, we developed a protocol for automated collection and fixation of marine microbes using the environmental sample processor (esp) platform. the protocol applies a preservat ... | 2011 | 21716310 |
| major differences of bacterial diversity and activity inside and outside of a natural iron-fertilized phytoplankton bloom in the southern ocean. | one of the first comparisons of a natural iron fertilized bloom with a high-nutrient low-chlorophyll (hnlc) site was undertaken during the kerguelen ocean and plateau compared study (keops) cruise. to understand better the bacteria-phytoplankton relationship in the context of natural iron fertilization, bacterial diversity and activity was investigated in the bloom and in the adjacent hnlc region by 16s rdna clone libraries and by single strand conformation polymorphism (sscp) analysis. both lib ... | 2008 | 18237307 |
| fulvibacter tottoriensis gen. nov., sp. nov., a member of the family flavobacteriaceae isolated from marine sediment. | a novel bacterium, mtt-39(t), was isolated from a sample of marine sediment collected at tottori on the coast of the sea of japan. cells were gram-negative, rod-shaped and non-motile. the bacterium formed yellowish brown colonies on marine agar 2216. although the 16s rrna gene sequence of strain mtt-39(t) classified this strain as a member of the family flavobacteriaceae, the maximum sequence similarity obtained was only 91.5 % (with kordia algicida ot-1(t)). in the maximum-likelihood tree based ... | 2008 | 18599714 |
| aestuariicola saemankumensis gen. nov., sp. nov., a member of the family flavobacteriaceae, isolated from tidal flat sediment. | a gram-negative, non-motile, pleomorphic bacterial strain, designated smk-142(t), was isolated from a tidal flat of the yellow sea, korea, and was subjected to a polyphasic taxonomic study. strain smk-142(t) grew optimally at ph 7.0-8.0, 25 degrees c and in the presence of 2% (w/v) nacl. phylogenetic analyses based on 16s rrna gene sequences showed that strain smk-142(t) clustered with lutibacter litoralis with which it exhibited a 16s rrna gene sequence similarity value of 91.2%. this cluster j ... | 2008 | 18768617 |
| exiguobacterium soli sp. nov., a psychrophilic bacterium from the mcmurdo dry valleys, antarctica. | a novel psychrophilic bacterium, designated strain dvs 3y(t), was isolated from a moraine sample from the mcmurdo dry valleys, antarctica. phenotypic and chemotaxonomic characteristics and data from a phylogenetic analysis based on 16s rrna gene sequences indicated that strain dvs 3y(t) was related to the genus exiguobacterium. strain dvs 3y(t) exhibited >97 % gene sequence similarity with respect to exiguobacterium acetylicum dsm 20416(t) (97.4 %), exiguobacterium oxidotolerans dsm 17272(t) (97 ... | 2008 | 18842873 |
| hellea balneolensis gen. nov., sp. nov., a prosthecate alphaproteobacterium from the mediterranean sea. | a novel aerobic, heterotrophic, prosthecate bacterium, designated 26iii/a02/215(t), was isolated from surface water of the north-western mediterranean sea. cells stained gram-negative and were straight to slightly curved rods, forming red colonies on agar plates. the strain grew at 15-37 degrees c inclusive (optimum 30 degrees c) and grew optimally at seawater salinity. growth was observed on organic acids, amino acids and complex organic substrates. the fatty acids (>5 %) detected in strain 26i ... | 2008 | 18984685 |
| anti-microfouling activity of lipidic metabolites from the invasive brown alga sargassum muticum (yendo) fensholt. | the purification of the chloroform extract from the brown invasive macroalga sargassum muticum, through a series of chromatographic separations, yielded 12 fractions that were tested against strains of bacteria, microalgae, and fungi involved in marine biofilm formation. the chemical composition of four (a, c, g, and k) out of the six fractions that exhibited anti-microfouling activity was investigated. fraction a contained saturated and unsaturated linear hydrocarbons (c12-c27). arachidonic aci ... | 2010 | 19468792 |
| transfer of sejongia antarctica, sejongia jeonii and sejongia marina to the genus chryseobacterium as chryseobacterium antarcticum comb. nov., chryseobacterium jeonii comb. nov. and chryseobacterium marinum comb. nov. | the genus sejongia was described in 2005, with the two species sejongia antarctica and sejongia jeonii, mainly on the basis of 16s rrna gene sequence analysis. at that time, these organisms formed a quite separate branch in a 16s rrna gene sequence-based tree, but, in subsequent studies, it became obvious that the species s. antarctica and s. jeonii and a third species, sejongia marina, were most closely related (>95.0% similarity) to some chryseobacterium species (e.g. chryseobacterium hominis, ... | 2009 | 19620362 |
| chryseobacterium palustre sp. nov. and chryseobacterium humi sp. nov., isolated from industrially contaminated sediments. | two gram-staining-negative bacterial strains, designated 3a10(t) and ecp37(t), were isolated from sediment samples collected from an industrially contaminated site in northern portugal. these two organisms were rod-shaped, non-motile, aerobic, catalase- and oxidase-positive and formed yellow colonies. the predominant fatty acids were iso-c(15 : 0), anteiso-c(15 : 0), iso-c(17 : 1)omega9c and iso-c(17 : 0) 3-oh. the g+c content of the dna of strains 3a10(t) and ecp37(t) was 43 and 34 mol%, respec ... | 2010 | 19651727 |
| [effect of cultivation parameters of antarctic strains enterobacter hormaechei and brevibacterium antarcticumon resistant to copper(ii) ions]. | enterobacter hormaechei and brevibacterium antarcticum strains isolated from ornithogenic soils of galindez island (west antarctica) were investigated for their resistance to cu2+ cations and for their capacity to cu2+ uptake from the environment. the studied strains are capable to grow in the concentration range of copper 100-1100 mg/l and to extract 11-75% of cu2+ from the environment depending on cultivation parameters and copper output concentration in the culture medium. | 2009 | 19938609 |
| molecular pedomorphism underlies craniofacial skeletal evolution in antarctic notothenioid fishes. | pedomorphism is the retention of ancestrally juvenile traits by adults in a descendant taxon. despite its importance for evolutionary change, there are few examples of a molecular basis for this phenomenon. notothenioids represent one of the best described species flocks among marine fishes, but their diversity is currently threatened by the rapidly changing antarctic climate. notothenioid evolutionary history is characterized by parallel radiations from a benthic ancestor to pelagic predators, ... | 2010 | 20053275 |
| distinct flavobacterial communities in contrasting water masses of the north atlantic ocean. | members of the class flavobacteria in the phylum bacteroidetes are among the most abundant picoplankton in coastal and polar oceans. their diversity is high in marine waters. however, quantitative information about distribution patterns of flavobacterial clades is scarce. we analyzed the diversity and clade-specific abundances of individual flavobacteria in different oceanic provinces in the north atlantic ocean. samples were taken along the 30 degrees w meridian between the east greenland curre ... | 2010 | 20054356 |
| terpenoid content of the antarctic soft coral alcyonium antarcticum. | chemical investigation of the soft coral alcyonium antarcticum, collected off terra nova bay, resulted in the isolation of two closely related sesquiterpenes, alcyonicene (1) and deacetoxy-alcyonicene (2), along with known terpenoid compounds. the structure elucidation of the new molecules, possessing a rare bulgarane skeleton, has been made mainly by nmr techniques. | 2009 | 20120093 |
| persistence of bacterial and archaeal communities in sea ice through an arctic winter. | the structure of bacterial communities in first-year spring and summer sea ice differs from that in source seawaters, suggesting selection during ice formation in autumn or taxon-specific mortality in the ice during winter. we tested these hypotheses by weekly sampling (january-march 2004) of first-year winter sea ice (franklin bay, western arctic) that experienced temperatures from -9 degrees c to -26 degrees c, generating community fingerprints and clone libraries for bacteria and archaea. des ... | 2010 | 20192970 |
| chryseobacterium chaponense sp. nov., isolated from farmed atlantic salmon (salmo salar). | two bacterial strains, designated sa 1147-06(t) and sa 1143-06, were isolated from atlantic salmon (salmo salar) farmed in lake chapo, chile, and were studied using a polyphasic approach. both isolates were very similar; cells were rod-shaped, formed yellow-pigmented colonies and were gram-reaction-negative. based on 16s rrna gene sequence analysis, strains sa 1147-06(t) and sa 1143-06 shared 100 % sequence similarity and showed 98.9 and 97.5 % sequence similarity to chryseobacterium jeonii at1 ... | 2011 | 20363929 |
| chryseobacterium yonginense sp. nov., isolated from a mesotrophic artificial lake. | a gram-staining-negative, non-motile, yellow-pigmented bacterial strain, designated hmd1043(t), was isolated from a mesotrophic artificial lake in korea. the major fatty acids were anteiso-c(15 : 0) (28.3 %), iso-c(15 : 0) (22.9 %), summed feature 9 (comprising iso-c(17 : 1)ω9c and/or 10-methyl c(16 : 0); 8.8 %) and iso-c(13 : 0) (5.3 %). the dna g+c content was 31.3 mol%. a phylogenetic tree based on 16s rrna gene sequences showed that strain hmd1043(t) formed a lineage within the genus chryseo ... | 2010 | 20601485 |
| polaribacter gangjinensis sp. nov., isolated from seawater. | a strictly aerobic, orange-pigmented and gram-staining-negative bacterium, designated k17-16(t), was isolated from seawater of gangjin bay, korea. comparative 16s rrna gene sequence analysis revealed that strain k17-16(t) was a member of the genus polaribacter in the family flavobacteriaceae and showed 94.0-95.6 % sequence similarity with the type strains of recognized species of the genus polaribacter. the g+c content of the genomic dna was 34.6 mol% and the major respiratory lipoquinone was mk ... | 2010 | 20622053 |
| roseicitreum antarcticum gen. nov. sp. nov., an aerobic bacteriochlorophyll a-containing alphaproteobacterium from antarctic sandy intertidal sediments. | a novel gram-negative, non-motile bacterium, designated zs2-28t, was isolated from sandy intertidal sediment samples collected from the coastal regions of the chinese antarctic zhongshan station on the larsemann hills, princess elizabeth land, east antarctica. strain zs2-28t was obligately heterotrophic, strictly aerobic, psychrotolerant (growth occurs at 0-33°c) and moderately halophilic (optimal nacl concentration of 7-8%). a single major peak in the infrared, at 872-874 nm, indicated the pres ... | 2010 | 20889763 |
| rescue of a cold-sensitive mutant at low temperatures by cold shock proteins from polaribacter irgensii kopri 22228. | exposure to low temperatures induces the biosynthesis of specific sets of proteins, including cold shock proteins (csps). since many of the specific functions of pychrophilic csps are unknown, the roles of csps from an arctic bacterium, polaribacter irgensii kopri 22228, were examined. the genes encoding cspa and cspc of p. irgensii were cloned in this study. sequence analysis showed that these proteins have cold shock domains containing two rna-binding motifs, rnp1 and rnp2. both proteins bound ... | 2010 | 21221937 |
| divergence of brain and retinal anatomy and histology in pelagic antarctic notothenioid fishes of the sister taxa dissostichus and pleuragramma. | the neutrally buoyant antarctic fishes of the sister taxa dissostichus (d. eleginoides and d. mawsoni) and pleuragramma antarcticum diverged early in the notothenioid radiation and filled different niches in the pelagic realm of the developing southern ocean. to assess the influence of phylogenetic and ecological factors in shaping neural morphology in these taxa, we studied the anatomy and histology of the brains and retinae, and determined the proportional weights of brain regions. with the br ... | 2011 | 21246598 |
| molecular and comparative analyses of type iv antifreeze proteins (afpivs) from two antarctic fishes, pleuragramma antarcticum and notothenia coriiceps. | antifreeze protein type iv (afpiv) cdnas and genomic dnas from the antarctic fishes pleuragramma antarcticum (pa) and notothenia coriiceps (nc) were cloned and sequenced, respectively. each cdna encoded 128 amino acids, with 94% similarity between the two and 83% similarity with afpiv of the longhorn sculpin, myoxocephalus octodecemspinosus. the genome structures of both genes consisted of four exons and three introns, and were highly conserved in terms of sequences and positions. in contrast, t ... | 2011 | 21571089 |
| psychrophilic yeasts from antarctica and european glaciers: description of glaciozyma gen. nov., glaciozyma martinii sp. nov. and glaciozyma watsonii sp. nov. | field campaigns in antarctica, greenland and the italian glaciers aiming to explore the biodiversity of these disappearing environments identified several undescribed yeast strains unable to grow at temperature above 20°c and belonging to unknown species. fourteen of these strains were selected and grouped based on their morphological and physiological characteristics. sequences of the d1/d2 and its regions of the ribosomal rna demonstrated that the strains belong to unknown species related to l ... | 2011 | 21796441 |
| marine bacterioplankton diversity and community composition in an antarctic coastal environment. | the bacterial community inhabiting the water column at terra nova bay (ross sea, antarctica) was examined by the fluorescent in situ hybridization (fish) technique and the genotypic and phenotypic characterization of 606 bacterial isolates. overall, the fish analysis revealed a bacterioplankton composition that was typical of antarctic marine environments with the cytophaga/flavobacter (cf) group of bacteroidetes that was equally dominant with the actinobacteria and gammaproteobacteria. as sampl ... | 2011 | 21748267 |
| biodiversity in the cladosporium herbarum complex (davidiellaceae, capnodiales), with standardisation of methods for cladosporium taxonomy and diagnostics. | the cladosporium herbarum complex comprises five species for which davidiella teleomorphs are known. cladosporium herbarum s. str. (d. tassiana), c. macrocarpum (d. macrocarpa) and c. bruhnei (d. allicina) are distinguishable by having conidia of different width, and by teleomorph characters. davidiella variabile is introduced as teleomorph of c. variabile, a homothallic species occurring on spinacia, and d. macrospora is known to be the teleomorph of c. iridis on iris spp. the c. herbarum compl ... | 2007 | 18490998 |
| genome analysis of the proteorhodopsin-containing marine bacterium polaribacter sp. med152 (flavobacteria). | analysis of marine cyanobacteria and proteobacteria genomes has provided a profound understanding of the life strategies of these organisms and their ecotype differentiation and metabolisms. however, a comparable analysis of the bacteroidetes, the third major bacterioplankton group, is still lacking. in the present paper, we report on the genome of polaribacter sp. strain med152. on the one hand, med152 contains a substantial number of genes for attachment to surfaces or particles, gliding motil ... | 2008 | 18552178 |
| evolution of antifreeze protein genes in the diatom genus fragilariopsis: evidence for horizontal gene transfer, gene duplication and episodic diversifying selection. | hypotheses about horizontal transfer of antifreeze protein genes to ice-living diatoms were addressed using two different statistical methods available in the program prunier. the role of diversifying selection in driving the differentiation of a set of antifreeze protein genes in the diatom genus fragilariopsis was also investigated. four horizontal gene transfer events were identified. two of these took place between two major eukaryote lineages, that is from the diatom chaetoceros neogracile ... | 2011 | 22253534 |
| neuroactive compounds produced by bacteria from the marine sponge halichondria panicea: activation of the neuronal nmda receptor. | previous studies revealed that the marine sponge halichondria panicea habors symbiotic- and commensalic bacteria (althoff et al., 1998. marine biol. 130, 529-536). in the present study the hypothesis was tested whether some of those bacteria synthesize neuroactive compounds. for the first time the effect of bacterial bioactive compounds on the neuronal ionotropic glutamate receptors [iglur], subtype n-methyl-d-aspartate (nmda) receptor, was checked. in cortical neurons from rats as cell system t ... | 1998 | 21781889 |
| genomic content of uncultured bacteroidetes from contrasting oceanic provinces in the north atlantic ocean. | bacteroidetes are widespread in marine systems where they play a crucial role in organic matter degradation. whole genome analysis of several strains has revealed a broad glycolytic and proteolytic potential. in this study, we used a targeted metagenomic approach to investigate the degradation capabilities of distinct bacteroidetes clades from two contrasting regions of the north atlantic ocean, the polar biome (bplr) and the north atlantic subtropical (nast). we present here the analysis of 76 ... | 2011 | 21895912 |