Among the dominant deltaproteobacterial sulfate-reducing bacteria (SRB), members of the genus Desulfobacula are not only present in (hydrocarbon-rich) marine sediments, but occur also frequently in the anoxic water bodies encountered in marine upwelling areas. Here, we present the 5.2 Mbp genome of Desulfobacula toluolica Tol2, which is the first of an aromatic compound-degrading, marine SRB.
View Article and Find Full Text PDFBackground: Several organisms display dormancy and developmental arrest at embryonic stages. Long-term survival in the dormant form is usually associated with desiccation, orthodox plant seeds and Artemia cysts being well documented examples. Several aquatic invertebrates display dormancy during embryonic development and survive for tens or even hundreds of years in a hydrated form, raising the question of whether survival in the non-desiccated form of embryonic development depends on pathways similar to those occurring in desiccation tolerant forms.
View Article and Find Full Text PDFThe gilthead sea bream, Sparus auratus, and the European sea bass, Dicentrarchus labrax, are two of the most important marine species cultivated in Southern Europe. This study aimed at increasing genomic resources for the two species and produced and annotated two sets of 30,000 expressed sequence tags (EST) each from 14 normalized tissue-specific cDNA libraries from sea bream and sea bass. Clustering and assembly of the ESTs formed 5268 contigs and 12,928 singletons for sea bream and 4573 contigs and 13,143 singletons for sea bass, representing 18,196 and 17,716 putative unigenes, respectively.
View Article and Find Full Text PDFDicentrarchus labrax is one of the major marine aquaculture species in the European Union. In this study, we have developed a directed-sequencing strategy to sequence three sea bass chromosomes and compared results with other teleosts. Three BAC DNA pools were created from sea bass BAC clones that mapped to stickleback chromosomes/groups V, XVII and XXI.
View Article and Find Full Text PDFThis study assessed the relationship between the occurrence and function of intronless or single exon genes (SEG) in the genome of five teleost species and their phylogenetic distance. The results revealed that Takifugu rubripes, Tetraodon nigroviridis, Oryzias latipes, Gasterosteus aculeatus and Danio rerio genomes are respectively comprised of 2.83%, 3.
View Article and Find Full Text PDFBackground: Food supply from the ocean is constrained by the shortage of domesticated and selected fish. Development of genomic models of economically important fishes should assist with the removal of this bottleneck. European sea bass Dicentrarchus labrax L.
View Article and Find Full Text PDFThe complete genome of the bacterium Erwinia tasmaniensis strain Et1/99 consisting of a 3.9 Mb circular chromosome and five plasmids was sequenced. Strain Et1/99 represents an epiphytic plant bacterium related to Erwinia amylovora and E.
View Article and Find Full Text PDFThe laboratory rat is one of the most extensively studied model organisms. Inbred laboratory rat strains originated from limited Rattus norvegicus founder populations, and the inherited genetic variation provides an excellent resource for the correlation of genotype to phenotype. Here, we report a survey of genetic variation based on almost 3 million newly identified SNPs.
View Article and Find Full Text PDFGlobal warming is associated with increasing stress and mortality on temperate seagrass beds, in particular during periods of high sea surface temperatures during summer months, adding to existing anthropogenic impacts, such as eutrophication and habitat destruction. We compare several expressed sequence tag (EST) in the ecologically important seagrass Zostera marina (eelgrass) to elucidate the molecular genetic basis of adaptation to environmental extremes. We compared the tentative unigene (TUG) frequencies of libraries derived from leaf and meristematic tissue from a control situation with two experimentally imposed temperature stress conditions and found that TUG composition is markedly different among these conditions (all P < 0.
View Article and Find Full Text PDFDehalococcoides species are strictly anaerobic bacteria, which catabolize many of the most toxic and persistent chlorinated aromatics and aliphatics by reductive dechlorination and are used for in situ bioremediation of contaminated sites. Our sequencing of the complete 1,395,502 base pair genome of Dehalococcoides strain CBDB1 has revealed the presence of 32 reductive-dehalogenase-homologous (rdh) genes, possibly conferring on the bacteria an immense dehalogenating potential. Most rdh genes were associated with genes encoding transcription regulators such as two-component regulatory systems or transcription regulators of the MarR-type.
View Article and Find Full Text PDFLeishmania species cause a spectrum of human diseases in tropical and subtropical regions of the world. We have sequenced the 36 chromosomes of the 32.8-megabase haploid genome of Leishmania major (Friedlin strain) and predict 911 RNA genes, 39 pseudogenes, and 8272 protein-coding genes, of which 36% can be ascribed a putative function.
View Article and Find Full Text PDFA microbial mat from the Black Sea shelf was analyzed by a metagenomic approach. While the habitat and its microbial community are characterized by anaerobic methane oxidation, a 79 kb contiguous DNA sequence obtained from the same mat provided first evidence for the concomitant presence of the capacity for anaerobic benzoate degradation. Benzoyl-CoA is one central intermediate of anaerobic aromatic degradation, among others.
View Article and Find Full Text PDFThe human X chromosome has a unique biology that was shaped by its evolution as the sex chromosome shared by males and females. We have determined 99.3% of the euchromatic sequence of the X chromosome.
View Article and Find Full Text PDFRecent research on microbial degradation of aromatic and other refractory compounds in anoxic waters and soils has revealed that nitrate-reducing bacteria belonging to the Betaproteobacteria contribute substantially to this process. Here we present the first complete genome of a metabolically versatile representative, strain EbN1, which metabolizes various aromatic compounds, including hydrocarbons. A circular chromosome (4.
View Article and Find Full Text PDFThe organization of all genes required for the anaerobic conversion of toluene to benzoyl-CoA was investigated in denitrifying Azoarcus-like strain EbN1. All of these genes are clustered within 25.3 kb of contiguous DNA sequence, which includes only a few intervening sequences.
View Article and Find Full Text PDFTogether with the hemichordates, sea urchins represent basal groups of nonchordate invertebrate deuterostomes that occupy a key position in bilaterian evolution. Because sea urchin embryos are also amenable to functional studies, the sea urchin system has emerged as one of the leading models for the analysis of the function of genomic regulatory networks that control development. We have analyzed a total of 107,283 cDNA clones of libraries that span the development of the sea urchin Strongylocentrotus purpuratus.
View Article and Find Full Text PDFGenes involved in anaerobic degradation of the petroleum hydrocarbon ethylbenzene in the denitrifying Azoarcus-like strain EbN1 were identified on a 56-kb DNA contig obtained from shotgun sequencing. Ethylbenzene is first oxidized via ethylbenzene dehydrogenase to (S)-1-phenylethanol; this is converted by (S)-1-phenylethanol dehydrogenase to acetophenone. Further degradation probably involves acetophenone carboxylase forming benzoylacetate, a ligase forming benzoylacetyl-CoA, and a thiolase forming acetyl-CoA and benzoyl-CoA.
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