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immunological properties and tissue localization of two different collagen types in annelid and vestimentifera species.rabbit antisera against cuticle and interstitial collagens from shallow sea water and hydrothermal vent annelids (arenicola marina, and the pompeii worm alvinella pompejana) and the vestimentiferan tube worm riftia pachyptila showed a clear distinction between the two types of collagens, a broad cross-reactivity among the worm collagens and no reactions with various mammalian collagens. the antibodies reacted with various epitopes found on both triple helical and unfolded collagens. the cuticle ...19947720731
pressure dependence of collagen melting.calf skin collagen type i and interstitial collagen of the annelids alvinella pompejana and riftia pachyptila were thermally unfolded at pressures of 1 and 200 bar. the high pressure was near the habitat pressure of the annelids which live in deep sea hydrothermal vents. the transition temperature increased with pressure by only 1.4 +/- 1 degrees c for calf skin collagen, and no pressure effect was detectable for the annelid collagens. the value for calf skin collagen agrees with prediction base ...19958535609
prolyl hydroxylase activity in tissue homogenates of annelids from deep sea hydrothermal vents.tissue homogenates of the deep sea annelids alvinella caudata and alvinella pompejana were found to contain enzyme activity resembling vertebrate prolyl 4-hydroxylase. the release of 3h2o from [3,4-(3)h]proline labeled, under-hydroxylated chicken protocollagen type i depended on the presence of the cofactors 2-oxoglutarate, ascorbate, fe2+ and o2. the release of 3h2o could be inhibited by the prolyl 4-hydroxylase inhibitors zinc, 2,2'-dipyridyl, 3,4-dihydroxybenzoic acid and pyridine-2,4-dicarbo ...19989707343
characterization of a novel spirochete associated with the hydrothermal vent polychaete annelid, alvinella pompejana.a highly integrated, morphologically diverse bacterial community is associated with the dorsal surface of alvinella pompejana, a polychaetous annelid that inhabits active high-temperature deep-sea hydrothermal vent sites along the east pacific rise (epr). analysis of a previously prepared bacterial 16s ribosomal dna (rdna) library identified a spirochete most closely related to an endosymbiont of the oligochete olavius loisae. this spirochete phylotype (spirochete a) comprised only 2.2% of the 1 ...200111133434
phylogenetic diversity of bacterial and archaeal communities in the anoxic zone of the cariaco basin.microbial community samples were collected from the anoxic zone of the cariaco basin at depths of 320, 500, and 1,310 m on a november 1996 cruise and were used to construct 16s ribosomal dna libraries. of 60 nonchimeric sequences in the 320-m library, 56 belonged to the epsilon subdivision of the proteobacteria (epsilon-proteobacteria) and 53 were closely related to ectosymbionts of rimicaris exoculata and alvinella pompejana, which are referred to here as epsilon symbiont relatives (esr). the 5 ...200111282619
a novel polymer produced by a bacterium isolated from a deep-sea hydrothermal vent polychaete annelid.the objective of the present work was to describe an aerobic, mesophilic and heterotrophic marine bacterium, designated hyd657, able to produce an exopolysaccharide (eps). it was isolated from a east pacific rise deep-sea hydrothermal vent polychaete annelid.200212147080
genome complexity and repetitive dna in metazoans from extreme marine environments.as genomics converges with ecology and evolution to identify the fundamental linkages between genome structure and function, genome and transcriptome complexity will need to be measured in organisms from more diverse habitats, most often in the absence of complete sequence data. here, we describe the complexity of ten genomes measured by a novel, high-throughput fluorescence-based kinetic hybridization assay. we applied the shannon information index, h, and a related, fluorescence-adjusted index ...200516188403
production and characterization of an exopolysaccharide excreted by a deep-sea hydrothermal vent bacterium isolated from the polychaete annelid alvinella pompejana.the heterotrophic and mesophilic marine bacterium hyd-1545 was isolated on a metal-amended medium from the dorsal integument of the hydrothermal vent polychaete alvinella pompejana. this strain, which can be assigned to the genus alteromonas on the basis of its g+c content and phenotypical features, produced large amounts of an acidic polysaccharide in batch cultures. the polysaccharide was excreted during the stationary phase of growth and contained glucose, galactose, glucuronic acid, galactur ...199416349441
characterization of a y-family dna polymerase eta from the eukaryotic thermophile alvinella pompejana.human dna polymerase η (hspolη) plays an important role in translesion synthesis (tls), which allows for replication past dna damage such as uv-induced cis-syn cyclobutane pyrimidine dimers (cpds). here, we characterized appolη from the thermophilic worm alvinella pompejana, which inhabits deep-sea hydrothermal vent chimneys. appolη shares sequence homology with hspolη and contains domains for binding ubiquitin and proliferating cell nuclear antigen. sun-induced uv does not penetrate alvinella's ...201020936172
phorcysia thermohydrogeniphila gen. nov., sp. nov., a thermophilic, chemolithoautotrophic, nitrate-ammonifying bacterium from a deep-sea hydrothermal vent on the east pacific rise.a novel hyperthermophilic, anaerobic, chemolithoautotrophic bacterium, designated strain hb-8t, was isolated from the tube of alvinella pompejana tubeworms collected from the wall of an actively venting sulfide structure on the east pacific rise at 13° n. the cells were gram-negative rods approximately 1-1.5 µm in length and 0.5 µm in width. strain hb-8t grew between 65 and 80 °c (optimum 75 °c), 15 and 35 g nacl l-1 (optimum 30 g l-1) and ph 4.5 and 8.5 (optimum ph 6.0). generation time under o ...201122140151
evidence of chemolithoautotrophy in the bacterial community associated with alvinella pompejana, a hydrothermal vent polychaete.the deep-sea polychaete alvinella pompejana colonizes tubes on the sides of black smoker chimneys along the east pacific rise. a diverse, yet phylogenetically constrained episymbiotic community is obligately associated with its dorsal surface. the morphologically and phylogenetically distinct dominant episymbionts have not yet been cultured, and there are no clearly defined roles for these bacteria in this symbiosis. a large insert fosmid library was screened for the presence of the two dominant ...200312957888
characterization and function of the first antibiotic isolated from a vent organism: the extremophile metazoan alvinella pompejana.the emblematic hydrothermal worm alvinella pompejana is one of the most thermo tolerant animal known on earth. it relies on a symbiotic association offering a unique opportunity to discover biochemical adaptations that allow animals to thrive in such a hostile habitat. here, by studying the pompeii worm, we report on the discovery of the first antibiotic peptide from a deep-sea organism, namely alvinellacin. after purification and peptide sequencing, both the gene and the peptide tertiary struct ...201424776651
functional and biochemical characterization of alvinella pompejana cys-loop receptor homologues.cys-loop receptors are membrane spanning ligand-gated ion channels involved in fast excitatory and inhibitory neurotransmission. three-dimensional structures of these ion channels, determined by x-ray crystallography or electron microscopy, have revealed valuable information regarding the molecular mechanisms underlying ligand recognition, channel gating and ion conductance. to extend and validate the current insights, we here present promising candidates for further structural studies. we repor ...201626999666
deep transcriptome-sequencing and proteome analysis of the hydrothermal vent annelid alvinella pompejana identifies the cvp-bias as a robust measure of eukaryotic thermostability.alvinella pompejana is an annelid worm that inhabits deep-sea hydrothermal vent sites in the pacific ocean. living at a depth of approximately 2500 meters, these worms experience extreme environmental conditions, including high temperature and pressure as well as high levels of sulfide and heavy metals. a. pompejana is one of the most thermotolerant metazoans, making this animal a subject of great interest for studies of eukaryotic thermoadaptation.201323324115
superoxide dismutase from the eukaryotic thermophile alvinella pompejana: structures, stability, mechanism, and insights into amyotrophic lateral sclerosis.prokaryotic thermophiles supply stable human protein homologs for structural biology; yet, eukaryotic thermophiles would provide more similar macromolecules plus those missing in microbes. alvinella pompejana is a deep-sea hydrothermal-vent worm that has been found in temperatures averaging as high as 68 degrees c, with spikes up to 84 degrees c. here, we used cu,zn superoxide dismutase (sod) to test if this eukaryotic thermophile can provide insights into macromolecular mechanisms and stability ...200919063897
metagenome analysis of an extreme microbial symbiosis reveals eurythermal adaptation and metabolic flexibility.hydrothermal vent ecosystems support diverse life forms, many of which rely on symbiotic associations to perform functions integral to survival in these extreme physicochemical environments. epsilonproteobacteria, found free-living and in intimate associations with vent invertebrates, are the predominant vent-associated microorganisms. the vent-associated polychaete worm, alvinella pompejana, is host to a visibly dense fleece of episymbionts on its dorsal surface. the episymbionts are a multispe ...200818987310
the splicing factor u2af65 is functionally conserved in the thermotolerant deep-sea worm alvinella pompejana.due to their inherent stability, thermophilic bacteria and archaea serve as important resources for biochemical and biophysical analyses of many biological processes. unfortunately, scientists characterizing eukaryote-specific processes, such as nuclear pre-mrna splicing, are unable to take advantage of these sources of thermostable proteins. to identify and provide a source of thermostable eukaryotic proteins, we are characterizing splicing factors in the thermotolerant deep-sea vent polychaete ...200515777616
nautilia lithotrophica gen. nov., sp. nov., a thermophilic sulfur-reducing epsilon-proteobacterium isolated from a deep-sea hydrothermal vent.a novel, strictly anaerobic, thermophilic sulfur-reducing bacterium, strain 525t, was isolated from tubes of the deep-sea hydrothermal vent polychaete alvinella pompejana, collected on the east pacific rise (13 degrees n). this organism grew in the temperature range 37-68 degrees c, the optimum being 53 degrees c, and in the ph range 6.4-7.4, the optimum being 6.8-7.0. the nacl range for growth was 0.8-5.0%, the optimum being 3.0%. strain 525t grew lithoautotrophically with h2 as energy source, ...200212148643
thermal biology of the deep-sea vent annelid paralvinella grasslei: in vivo studies.the annelid paralvinella grasslei is a deep-sea vent endemic species that colonizes the wall of active chimneys. we report here the first data on its thermal biology based on in vivo experiments in pressurized aquaria. our results demonstrate that p. grasslei survives a 30 min exposure at 30 degrees c, and suggest that the upper thermal limit of this species is slightly above this temperature. the first signs of stress were noticed at 30 degrees c, such as a significant increase in the animal's ...200818587113
engenius -- environmental genome informational utility system.short-insert shotgun sequencing approaches have been applied in recent years to environmental genomic libraries. in the case of complex multispecies microbial communities, there can be many sequence reads that are not incorporated into assemblies, and thus need to be annotated and accessible as single reads. most existing annotation systems and genome databases accommodate assembled genomes containing contiguous gene-encoding sequences. thus, a solution is required that can work effectively with ...200819090024
response of alvinella pompejana to variable oxygen stress: a proteomic approach.alvinella pompejana is one of the most emblematic species of the animal communities colonizing the deep-sea hydrothermal vents of the east pacific rise. this extreme environment is characterized by high temporal variability of its physical-chemical parameters. among these, the variation in concentration of available oxygen should lead to a specific physiological adaptive response of the animal. to evaluate the mechanisms of this response at a molecular level, a classical 2-de-based proteomic app ...201020376861
determining gene flow and the influence of selection across the equatorial barrier of the east pacific rise in the tube-dwelling polychaete alvinella pompejana.comparative phylogeography recently performed on the mitochondrial cytochrome oxidase i (mtcoi) gene from seven deep-sea vent species suggested that the east pacific rise fauna has undergone a vicariant event with the emergence of a north/south physical barrier at the equator 1-2 mya. within this specialised fauna, the tube-dwelling polychaete alvinella pompejana showed reciprocal monophyly at mtcoi on each side of the equator (9 degrees 50'n/7 degrees 25's), suggesting potential, ongoing allopa ...201020663123
insights into metazoan evolution from alvinella pompejana cdnas.alvinella pompejana is a representative of annelids, a key phylum for evo-devo studies that is still poorly studied at the sequence level. a. pompejana inhabits deep-sea hydrothermal vents and is currently known as one of the most thermotolerant eukaryotes in marine environments, withstanding the largest known chemical and thermal ranges (from 5 to 105°c). this tube-dwelling worm forms dense colonies on the surface of hydrothermal chimneys and can withstand long periods of hypo/anoxia and long p ...201021080938
new digestive symbiosis in the hydrothermal vent amphipoda ventiella sulfuris.ventiella sulfuris barnard and ingram, 1990 is the most abundant amphipod species inhabiting the eastern pacific rise (epr 9°n) vent fields. this vent-endemic species is frequently encountered near colonies of pompeii worms alvinella pompejana. v. sulfuris specimens were collected during the oceanographic cruise ladder ii at the bio9 (9°50.3'n, 2508m depth) hydrothermal vent site. main objectives were to highlight the occurrence of bacterial symbiosis in v. sulfuris and to hypothesise their impl ...201222325568
spatial and temporal variations in food web structure from newly-opened habitat at hydrothermal vents.to highlight the spatio-temporal variability of the food web structure of hydrothermal vent fauna from newly-opened habitat, a series of titanium ring for alvinellid colonization devices (tracs) was deployed at tica site on the east pacific rise in 2006. this experiment was conducted for periods of 4 days, 13 days and one month and deployments were aligned along a gradient from the basaltic bottom to the vent openings. δ(13)c values of colonists revealed a narrower range of carbon sources in pro ...201222503949
detection and characterisation of mutations responsible for allele-specific protein thermostabilities at the mn-superoxide dismutase gene in the deep-sea hydrothermal vent polychaete alvinella pompejana.alvinella pompejana (polychaeta, alvinellidae) is one of the most thermotolerant marine eukaryotes known to date. it inhabits chimney walls of deep-sea hydrothermal vents along the east pacific rise (epr) and is exposed to various challenging conditions (e.g. high temperature, hypoxia and the presence of sulphides, heavy metals and radiations), which increase the production of dangerous reactive oxygen species (ros). two different allelic forms of a manganese-superoxide dismutase involved in ros ...201323608997
thermal limit for metazoan life in question: in vivo heat tolerance of the pompeii worm.the thermal limit for metazoan life, expected to be around 50°c, has been debated since the discovery of the pompeii worm alvinella pompejana, which colonizes black smoker chimney walls at deep-sea vents. while indirect evidence predicts body temperatures lower than 50°c, repeated in situ temperature measurements depict an animal thriving at temperatures of 60°c and more. this controversy was to remain as long as this species escaped in vivo investigations, due to irremediable mortalities upon n ...201323734185
copper/zinc superoxide dismutase from the cladoceran daphnia magna: molecular cloning and expression in response to different acute environmental stressors.the copper/zinc superoxide dismutase (cu/zn-sod) is a representative antioxidant enzyme that is responsible for the conversion of superoxide to oxygen and hydrogen peroxide in aerobic organisms. cu/zn-sod mrnas have been cloned from many species and employed as useful biomarkers of oxidative stresses. in the present study, we cloned cu/zn-sod cdna from the cladoceran daphnia magna, analyzed its catalytic properties, and investigated mrna expression patterns after exposure to known oxidative stre ...201323815380
an internally modulated, thermostable, ph-sensitive cys loop receptor from the hydrothermal vent worm alvinella pompejana.cys loop receptors (clrs) are commonly known as ligand-gated channels that transiently open upon binding of neurotransmitters to modify the membrane potential. however, a class of cation-selective bacterial homologues of clrs have been found to open upon a sudden ph drop, suggesting further ligands and more functions of the homologues in prokaryotes. here we report an anion-selective clr from the hydrothermal vent annelid worm alvinella pompejana that opens at low ph. a. pompejana expressed sequ ...201424719323
population subdivision of hydrothermal vent polychaete alvinella pompejana across equatorial and easter microplate boundaries.the equator and easter microplate regions of the eastern pacific ocean exhibit geomorphological and hydrological features that create barriers to dispersal for a number of animals associated with deep-sea hydrothermal vent habitats. this study examined effects of these boundaries on geographical subdivision of the vent polychaete alvinella pompejana. dna sequences from one mitochondrial and eleven nuclear genes were examined in samples collected from ten vent localities that comprise the species ...201627793079
proteome evolution of deep-sea hydrothermal vent alvinellid polychaetes supports the ancestry of thermophily and subsequent adaptation to cold in some lineages.temperature, perhaps more than any other environmental factor, is likely to influence the evolution of all organisms. it is also a very interesting factor to understand how genomes are shaped by selection over evolutionary timescales, as it potentially affects the whole genome. among thermophilic prokaryotes, temperature affects both codon usage and protein composition to increase the stability of the transcriptional/translational machinery, and the resulting proteins need to be functional at hi ...201728082607
exopolysaccharide biosynthesis and biodegradation by a marine hydrothermal alteromonas sp. strain.alteromonas macleodii subsp. fijiensis biovar deepsane is a deep-sea ecotype exopolysaccharide-producing bacteria isolated from the polychaete annelid alvinella pompejana. the high molecular weight biopolymer hyd657 produced by this strain, is the first marine exopolysaccharide (eps) to be commercialized for cosmetic use. depolymerization methods are necessary to elucidate the complete structure of this eps and to generate potentially bioactive oligosaccharides. enzymatic methods are useful for ...201525319363
enzymic approach to eurythermalism of alvinella pompejana and its episymbionts.the equilibrium model, which describes the influence of temperature on enzyme activity, has been established as a valid and useful tool for characterizing enzyme eurythermalism and thermophily. by introducing k(eq), a temperature-dependent equilibrium constant for the interconversion between e(act), the active form of enzyme, and e(inact), a reversibly inactive form of enzyme, the equilibrium model currently provides the most complete description of the enzyme-temperature relationship; its deriv ...200818083873
globin gene family evolution and functional diversification in annelids.globins are the most common type of oxygen-binding protein in annelids. in this paper, we show that circulating intracellular globin (alvinella pompejana and glycera dibranchiata), noncirculating intracellular globin (arenicola marina myoglobin) and extracellular globin from various annelids share a similar gene structure, with two conserved introns at canonical positions b12.2 and g7.0. despite sequence divergence between intracellular and extracellular globins, these data strongly suggest that ...200717451435
uncultured archaea in a hydrothermal microbial assemblage: phylogenetic diversity and characterization of a genome fragment from a euryarchaeote.the polychaete alvinella pompejana lives in organic tubes on the walls of active hydrothermal chimneys along the east pacific rise. to examine the diversity of the archaeal community associated with the polychaete tubes, we constructed libraries by direct pcr amplification and cloning of 16s rrna genes. almost half of the sequences of the 16s rrna gene libraries clustered with uncultured archaeal groups. in an effort to access genomic information from uncultured archaeal members we further const ...200616907759
diversity of dissimilatory bisulfite reductase genes of bacteria associated with the deep-sea hydrothermal vent polychaete annelid alvinella pompejana.a unique community of bacteria colonizes the dorsal integument of the polychaete annelid alvinella pompejana, which inhabits the high-temperature environments of active deep-sea hydrothermal vents along the east pacific rise. the composition of this bacterial community was characterized in previous studies by using a 16s rrna gene clone library and in situ hybridization with oligonucleotide probes. in the present study, a pair of pcr primers (p94-f and p93-r) were used to amplify a segment of th ...199910049872
distinct patterns of genetic differentiation among annelids of eastern pacific hydrothermal vents.population genetic and phylogenetic analyses of mitochondrial coi from five deep-sea hydrothermal vent annelids provided insights into their dispersal modes and barriers to gene flow. these polychaetes inhabit vent fields located along the east pacific rise (epr) and galapagos rift (gar), where hundreds to thousands of kilometers can separate island-like populations. long-distance dispersal occurs via larval stages, but larval life histories differ among these taxa. mitochondrial gene flow betwe ...200415315674
phylogenetic diversity of dissimilatory sulfite reductase genes from deep-sea cold seep sediment.the phylogenetic diversity of dissimilatory sulfite reductase (dsr, ec 1.8.99.3) alpha-subunit genes from a deep-sea cold seep was analyzed. bulk genomic dna was extracted from the cold seep sediment and used for amplification by polymerase chain reaction (pcr) of dsr alpha-subunit gene. two sizes of pcr products, 1.4 kb (expected) and 1.3 kb (unexpected), were amplified. sixteen clones of the 1.4-kb amplicons and 16 clones of 1.3-kb amplicons, a total of 32 clones, were obtained and grouped int ...201214730429
revisiting the structure of alvinella pompejana hemoglobin at 20a resolution by cryoelectron microscopy.the hemoglobin of the polychaete worm alvinella pompejana was reconstructed at 20a resolution from frozen-hydrated samples observed by electron microscopy according to the random conical tilt series method. this three-dimensional reconstruction was mirror-inverted with respect to a previous volume published by de haas et al. in 1996. in order to explain this handedness discrepancy, various 3d reconstructions using different reference volumes were carried out showing that the choice of the first ...200312892724
deep-sea ecology. developmental arrest in vent worm embryos.temperature is a key factor in controlling the distribution of marine organisms and is particularly important at hydrothermal vents, where steep thermal gradients are present over a scale of centimetres. the thermophilic worm alvinella pompejana, which is found at the vents of the east pacific rise (2,500-m depth), has an unusually broad thermotolerance (20-80 degrees c) as an adult, but we show here that the temperature range required by the developing embryo is very different from that tolerat ...200111607020
observation of large, non-covalent globin subassemblies in the approximately 3600 kda hexagonal bilayer hemoglobins by electrospray ionization time-of-flight mass spectrometry.a non-covalent globin subassembly comprising 12 globin chains (204 to 214 kda) was observed directly by electrospray ionization time-of-flight mass spectrometry in the native hexagonal bilayer hemoglobins from the oligochaetes lumbricus terrestris and tubifex tubifex, the polychaetes tylorrhynchus heterochaetus, arenicola marina, amphitrite ornata and alvinella pompejana, the leeches macrobdella decora, haemopis grandis and nephelopsis oscura and the chlorocruorin from the polychaete myxicola in ...200111397079
influence of environmental conditions on early development of the hydrothermal vent polychaete alvinella pompejana.dispersal and colonisation processes at deep-sea vents are still not fully understood, essentially because early life stages of vent species remain unknown. the polychaete worm alvinella pompejana forms colonies on chimney walls at east pacific rise vent sites where the temperature can frequently exceed 20 degrees c. in vitro studies in pressure vessels showed that the early embryos tolerate temperatures in a lower range (10-14 degrees c), suggesting that they would have to escape the colony to ...200515802678
thermal selection of pgm allozymes in newly founded populations of the thermotolerant vent polychaete alvinella pompejana.alvinella pompejana lives on the top of chimneys at deep-sea hydrothermal vents of the east pacific rise. it is thought to be one of the most thermotolerant and eurythermal metazoans. our experimental approach combines methods of population genetics and biochemistry, considering temperature as a potential selective factor. phosphoglucomutase (pgm-1 locus) is one of the most polymorphic loci of a. pompejana and exhibits four alleles, from which alleles 90 and 100 dominate with frequencies of appr ...200415556887
structural data on a bacterial exopolysaccharide produced by a deep-sea alteromonas macleodii strain.some marine bacteria collected around deep-sea hydrothermal vents are able to produce, in laboratory conditions, complex and innovative exopolysaccharides. in a previous study, the mesophilic strain alteromonas macleodii subsp. fijiensis biovar deepsane was collected on the east pacific rise at 2600 m depth. it was isolated from a polychaete annelid alvinella pompejana and is able to synthesise and excrete the exopolysaccharide deepsane. biological activities have been screened and some protecti ...201224751009
adaptations to submarine hydrothermal environments exemplified by the genome of nautilia profundicola.submarine hydrothermal vents are model systems for the archaean earth environment, and some sites maintain conditions that may have favored the formation and evolution of cellular life. vents are typified by rapid fluctuations in temperature and redox potential that impose a strong selective pressure on resident microbial communities. nautilia profundicola strain am-h is a moderately thermophilic, deeply-branching epsilonproteobacterium found free-living at hydrothermal vents and is a member of ...200919197347
bacterial communities associated with "pompei worms" from the east pacific rise hydrothermal vents: sem, tem observations.a morphological study of bacteria associated with the "pompei worm,"alvinella pompejana, collected from east pacific rise hydrothermal vents, revealed four types of epidermal associations on the dorsal part of the animals: various single cells distributed on the animal tegument; clump-like associations located in the intertegumentary spaces; and filamentous bacteria associated with epidermal expansions, or inserted on the posterior parapodia. the bacterial morphologies were illustrated by sem an ...198724213211
supercoil of collagen fibrils in the integument of alvinella, an abyssal annelid.the polychaete annelid alvinella pompejana was discovered near the hydrothermal vents, recently explored in the eastern pacific ocean. this worm is protected by a cuticle deeply transformed over certain areas of the body and some changes are due to the presence of a very special bacterial flora. the present work however deals mainly with the supercoiled collagen fibrils, which are well visualized in thin sections observed by transmission electron microscopy. this character strongly differentiate ...198718620215
occurrence of two architectural types of hexagonal bilayer hemoglobin in annelids: comparison of 3d reconstruction volumes of arenicola marina and lumbricus terrestris hemoglobins.a 3d reconstruction at 25 a resolution of native hemoglobin of the polychaete worm arenicola marina was carried out from frozen-hydrated specimens examined in the electron microscope. the reconstruction volume of this large extracellular multimeric respiratory pigment appears as a hexagonal bilayer structure with eclipsed vertices in its upper and lower hexagonal layers. conversely, in hemoglobins of oligochaetes, achaetes, and vestimentiferans and in chlorocruorins of the sabellidae (polychaete ...200111162090
molecular adaptation to an extreme environment: origin of the thermal stability of the pompeii worm collagen.the annelid alvinella pompejana is probably the most heat-tolerant metazoan organism known. previous results have shown that the level of thermal stability of its interstitial collagen is significantly greater than that of coastal annelids and of vent organisms, such as the vestimentiferan riftia pachyptila, living in colder parts of the deep-sea hydrothermal environment. in order to investigate the molecular basis of this thermal behavior, we cloned and sequenced a large cdna molecule coding th ...200010993725
polypeptide chain composition diversity of hexagonal-bilayer haemoglobins within a single family of annelids, the alvinellidae.following previous analysis of the structure of alvinella pompejana heaxagonal-bilayer haemoglobin (hbl hb) [1], we report in this paper the structure of three other hbl hbs belonging to alvinella caudata, paralvinella grasslei and paralvinella palmiformis, members of the alvinellidae, annelid family strictly endemic to deep-sea hydrothermal vents located on the ridge crests in the pacific ocean. the multi-angle laser light scattering (malls) and fast protein liquid chromatography (fplc) analysi ...200010931208
gas transfer system in alvinella pompejana (annelida polychaeta, terebellida): functional properties of intracellular and extracellular hemoglobins.alvinella pompejana is a tubicolous polychaete that dwells in the hottest part of the hydrothermal vent ecosystem in a highly variable mixture of vent (350 degrees c, anoxic, co(2)- and sulfide-rich) and deep-sea (2 degrees c, mildly hypoxic) waters. this species has developed distinct-and specifically respiratory-adaptations to this challenging environment. an internal gas exchange system has recently been described, along with the report of an intracellular coelomic hemoglobin, in addition to ...201310893176
new analysis of the phylogenetic change of collagen thermostability.recent data concerning the thermostability and the primary structure of type iv collagens, some invertebrate collagens, and for the stability of synthetic collagen-like polypeptides, show that our earlier analysis of the phylogenetic change of thermostability has some shortcomings. the results of the analysis were corrected and it has been shown that the dependence of denaturation temperature td on 4-hydroxyproline content is hyperbolic and the total gly-pro-hyp sequence content is a main, but n ...200010775067
investigation by electrospray ionization mass spectrometry of the extracellular hemoglobin from the polychaete annelid alvinella pompejana: an unusual hexagonal bilayer hemoglobin.alvinella pompejana inhabits deep-sea hydrothermal vent sites along the east-pacific rise, where it colonizes the walls of actively venting high-temperature chimneys. this worm is the most thermophilic metazoan known to date. in alvinella, as in other alvinellids, oxygen transport is mainly achieved by an extracellular hb dissolved in the vascular blood. this hb has a molecular mass of 3833 +/- 14 kda as revealed by multiangle laser light scattering (malls). native and derivative hb (reduced, ca ...19979305968
molecular identification and localization of filamentous symbiotic bacteria associated with the hydrothermal vent annelid alvinella pompejana.alvinella pompejana is a polychaetous annelid that inhabits high-temperature environments associated with active deep-sea hydrothermal vents along the east pacific rise. a unique and diverse epibiotic microflora with a prominent filamentous morphotype is found associated with the worm's dorsal integument. a previous study established the taxonomic positions of two epsilon proteobacterial phylotypes, 13b and 5a, which dominated a clone library of 16s rrna genes amplified by pcr from the epibiotic ...199716535543
three-dimensional reconstruction by cryoelectron microscopy of the giant hemoglobin of the polychaete worm alvinella pompejana.a frozen-hydrated specimen of the hexagonal bilayer hemoglobin (hbl hb) from the deep-sea hydrothermal vent polychaete worm alvinella pompejana, the most thermophilic metazoan known to date, was observed in the electron microscope and subjected to three-dimensional (3d) reconstruction by the method of random conical tilt series. at a resolution of 34.6 a by the differential phase residual method and 27.7 a by the fourier shell correlation method, the 3d volume possesses a d6 point-group symmetry ...19968950271
phylogenetic characterization of the epibiotic bacteria associated with the hydrothermal vent polychaete alvinella pompejana.alvinella pompejana is a polychaetous annelid that inhabits active deep-sea hydrothermal vent sites along the east pacific rise, where it colonizes the walls of actively venting high-temperature chimneys. an abundant, morphologically diverse epibiotic microflora is associated with the worm's dorsal integument, with a highly integrated filamentous morphotype clearly dominating the microbial biomass. it has been suggested that this bacterial population participates in either the nutrition of the w ...19957544093
structural comparison of cuticle and interstitial collagens from annelids living in shallow sea-water and at deep-sea hydrothermal vents.two types of annelid collagens of different sizes were purified, one from acetic acid extracts of the cuticle (length 2.5 microns) and the other, after pepsin digestion, from interstitial spaces of the body wall (0.3 micron). they were obtained from alvinella pompejana, alvinella caudata and paralvinella grasslei collected at 2600 m depth around anoxic hydrothermal vents and from arenicola marina and nereis diversicolor living in shallow sea-water habitats. the length of the corresponding collag ...19957869380
molecular characterization of cuticle and interstitial collagens from worms collected at deep sea hydrothermal vents.two different collagens were isolated and characterized from the body walls of the vestimentiferan tube worm riftia pachyptila and the annelid alvinella pompejana, both living around hydrothermal vents at a depth of 2600 m. the acid-soluble cuticle collagens consisted of a long triple helix (2.4 microns for alvinella, 1.5 microns for riftia) terminating into a globular domain. molecular masses of 2600 and 1700 kda, respectively, were estimated from their dimensions. the two cuticle collagens wer ...19911920405
isolation and characterization of methylated sugars from the tube of the hydrothermal vent tubiculous annelid worm alvinella pompejana.the tube of alvinella pompejana contains in its carbohydrate fraction, 3 methylated monosaccharides: 2-mono-o-methyl-l-fucose, 3-mono-o-methyl-l-fucose and 2,4-di-o-methyl-l-fucose. the present work appears to be the first report of the occurrence of 2-mono-o-methyl-l-fucose and 3-mono-o-methyl-l-fucose in the animal kingdom. moreover, it is the first time that 2,4-di-o-methyl-l-fucose is found in nature.19912015909
gene structure and molecular phylogeny of the linker chains from the giant annelid hexagonal bilayer hemoglobins.giant extracellular hexagonal bilayer hemoglobin (hbl-hb), found only in annelids, is an approximately 3500-kda heteropolymeric structure involved in oxygen transport. the hbl-hbs are comprised of globin and linker chains, the latter being required for the assembly of the quaternary structure. the linker chains, varying in size from 225 to 283 amino acids, have a conserved cysteine-rich domain within their n-terminal moiety that is homologous to the cysteine-rich modules constituting the ligand ...200616838215
growth and phylogenetic properties of novel bacteria belonging to the epsilon subdivision of the proteobacteria enriched from alvinella pompejana and deep-sea hydrothermal vents.recent molecular characterizations of microbial communities from deep-sea hydrothermal sites indicate the predominance of bacteria belonging to the epsilon subdivision of proteobacteria (epsilon proteobacteria). here, we report the first enrichments and characterizations of four epsilon proteobacteria that are directly associated with alvinella pompejana, a deep sea hydrothermal vent polychete, or with hydrothermal vent chimney samples. these novel bacteria were moderately thermophilic sulfur-re ...200111571157
susceptibility to heavy metals and characterization of heterotrophic bacteria isolated from two hydrothermal vent polychaete annelids, alvinella pompejana and alvinella caudata.specimens of alvinellid polychaetes and their tubes were collected in the parigo hydrothermal vent field on the east pacific rise (13 degrees n) in october and november 1987. heterotrophic bacterial strains were isolated on metal-amended media from the tube and dorsal integument of one specimen of alvinella pompejana, from the dorsal integument of another from the whole integument of a specimen of alvinella caudata, and from undetermined alvinellid tubes. the strains were characterized and teste ...199016348338
vibrio diabolicus sp. nov., a new polysaccharide-secreting organism isolated from a deep-sea hydrothermal vent polychaete annelid, alvinella pompejana.a deep-sea, facultatively anaerobic, heterotrophic, mesophilic new organism was isolated from the polychaete annelid alvinella pompejana collected from a deep-sea hydrothermal field in the east pacific rise. on the basis of phenotypic characteristics, phylogenetic analyses, and dna-dna relatedness, this organism was identified as a new species of the genus vibrio, for which the name vibrio diabolicus is proposed. in batch cultures in the presence of glucose, this organism produced an innovative ...19979336897
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