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Full-Text Articles in Life Sciences

Genomic Versatility And Functional Variation Between Two Dominant Heterotrophic Symbionts Of Deep-Sea Osedax Worms, Shana K. Goffredi, Hana Yi, Qingpeng Zhang, Jane E. Klann, Isabelle A. Struve, Robert C. Vrijenhoek, C Titus Brown Mar 2013

Genomic Versatility And Functional Variation Between Two Dominant Heterotrophic Symbionts Of Deep-Sea Osedax Worms, Shana K. Goffredi, Hana Yi, Qingpeng Zhang, Jane E. Klann, Isabelle A. Struve, Robert C. Vrijenhoek, C Titus Brown

Shana Goffredi

An unusual symbiosis, first observed at ~3000 m depth in the Monterey Submarine Canyon, involves gutless marine polychaetes of the genus Osedax and intracellular endosymbionts belonging to the order Oceanospirillales. Ecologically, these worms and their microbial symbionts have a substantial role in the cycling of carbon from deep-sea whale fall carcasses. Microheterogeneity exists among the Osedax symbionts examined so far, and in the present study the genomes of the two dominant symbionts, Rs1 and Rs2, were sequenced. The genomes revealed heterotrophic versatility in carbon, phosphate and iron uptake, strategies for intracellular survival, evidence for an independent existence, and numerous potential …


Bromeliad Catchments As Habitats For Methanogenesis In Tropical Rainforest Canopies, Shana K. Goffredi, Gene E. Jang, Walter T. Woodside, William Ussler Iii Dec 2010

Bromeliad Catchments As Habitats For Methanogenesis In Tropical Rainforest Canopies, Shana K. Goffredi, Gene E. Jang, Walter T. Woodside, William Ussler Iii

Shana Goffredi

Tropical epiphytic plants within the family Bromeliaceae are unusual in that they possess foliage capable of retaining water and impounded material. This creates an acidic (pH 3.5-6.5) and anaerobic (<1 ppm O(2)) environment suspended in the canopy. Results from a Costa Rican rainforest show that most bromeliads (n = 75/86) greater than ~20 cm in plant height or ~4-5 cm tank depth, showed presence of methanogens within the lower anoxic horizon of the tank. Archaea were dominated by methanogens (77-90% of recovered ribotypes) and community structure, although variable, was generally comprised of a single type, closely related to either hydrogenotrophic Methanoregula or Methanocella, a specific clade of aceticlastic Methanosaeta, or Methanosarcina. Juvenile bromeliads, or those species, such as Guzmania, with shallow tanks, generally did not possess methanogens, as assayed by polymerase chain reaction specific for methanogen 16S rRNA genes, nor did artificial catchments (~100 ml volume), in place 6-12 months prior to sample collection. Methanogens were not detected in soil (n = 20), except in one case, in which the dominant ribotype was different from nearby bromeliads. Recovery of methyl coenzyme M reductase genes supported the occurrence of hydrogenotrophic and aceticlastic methanogens within bromeliad tanks, as well as the trend, via QPCR analysis of mcrA, of increased methanogenic capacity with increased plant height. Methane production rates of up to 300 nmol CH(4) ml tank water(-1) day(-1) were measured in microcosm experiments. These results suggest that bromeliad-associated archaeal communities may play an important role in the cycling of carbon in neotropical forests.


Indigenous Ectosymbiotic Bacteria Associated With Diverse Hydrothermal Vent Invertebrates, Shana K. Goffredi Dec 2009

Indigenous Ectosymbiotic Bacteria Associated With Diverse Hydrothermal Vent Invertebrates, Shana K. Goffredi

Shana Goffredi

Symbioses involving bacteria and invertebrates contribute to the biological diversity and high productivity of both aquatic and terrestrial environments. Well-known examples from chemosynthetic deep-sea hydrothermal vent environments involve ectosymbiotic microbes associated with the external surfaces of marine invertebrates. Some of these ectosymbioses confer protection or defence from predators or the environment itself, some are nutritional in nature, and many still are of unknown function. Several recently discovered hydrothermal vent invertebrates, including two populations of yeti crab (Kiwa spp.), a limpet (Symmetromphalus aff. hageni), and the scaly-foot snail (as yet undescribed), support a consortium of diverse bacteria. Comparisons of these ectosymbioses …


Temporal Evolution Of Methane Cycling And Phylogenetic Diversity Of Archaea In Sediments From A Deep-Sea Whale Fall In Monterey Canyon (Ca), Shana K. Goffredi, Regina Wilpiszeski, Ray Lee, Victoria J. Orphan Jan 2008

Temporal Evolution Of Methane Cycling And Phylogenetic Diversity Of Archaea In Sediments From A Deep-Sea Whale Fall In Monterey Canyon (Ca), Shana K. Goffredi, Regina Wilpiszeski, Ray Lee, Victoria J. Orphan

Shana Goffredi

Whale-falls represent localized areas of extreme organic enrichment in an otherwise oligotrophic deep-sea environment. Anaerobic remineralization within these habitats is typically portrayed as sulfidogenic; however, we demonstrate that these systems are also favorable for diverse methane-producing archaeal assemblages, representing up to 40% of total cell counts. Chemical analyses revealed elevated methane and depleted sulfate concentrations in sediments under the whale-fall, as compared to surrounding sediments. Carbon was enriched (up to 3.5%) in whale-fall sediments, as well as the surrounding sea floor to at least 10 m, forming a ‘bulls eye’ of elevated carbon. The diversity of sedimentary archaea associated with …


Genetic Diversity And Potential Function Of Microbial Symbionts Associated With Newly Discovered Species Of Osedax Polychaete Worms, Shana K. Goffredi, Shannon B. Johnson, Robert C. Vrijenhoek Mar 2007

Genetic Diversity And Potential Function Of Microbial Symbionts Associated With Newly Discovered Species Of Osedax Polychaete Worms, Shana K. Goffredi, Shannon B. Johnson, Robert C. Vrijenhoek

Shana Goffredi

We investigated the genetic diversity of symbiotic bacteria associated with two newly discovered species of Osedax from Monterey Canyon, CA, at 1,017-m (Osedax Monterey Bay sp. 3 “rosy” [Osedax sp. MB3]) and 381-m (Osedax Monterey Bay sp. 4 “yellow collar”) depths. Quantitative PCR and clone libraries of 16S rRNA gene sequences identified differences in the compositions and abundances of bacterial phylotypes associated with the newly discovered host species and permitted comparisons between adult Osedax frankpressi and juveniles that had recently colonized whalebones implanted at 2,891 m. The newly discovered Osedax species hosted Oceanospirillales symbionts that are related to Gammaproteobacteria associated …


Molecular Detection Of Marine Invertebrate Larvae, Shana Goffredi, William J. Jones, Christopher A. Scholin, Roman Marin Iii, Robert C. Vrijenhoek Dec 2005

Molecular Detection Of Marine Invertebrate Larvae, Shana Goffredi, William J. Jones, Christopher A. Scholin, Roman Marin Iii, Robert C. Vrijenhoek

Shana Goffredi

The ecological patterns of many invertebrate larvae remain an ongoing mystery, in large part owing to the difficult task of detecting them in the water column. The development of nucleic-acid-based technology has the potential to resolve this issue by direct identification and monitoring of embryonic and larval forms in situ. We report herein on the successful development and application of nucleic-acid-based sandwich hybridization assays that detect barnacles using rRNA-targeted probes with both group-(order Thoracica) and species-(Balanus glandula) specificity. Primary results include the determination of target 18S rRNA sequences and the construction of "capture" probes for detection of larvae using hybridization …


Evolutionary Innovation: A Bone-Eating Marine Symbiosis, Shana K. Goffredi, Victoria J. Orphan, Greg W. Rouse, Linda Jahnke, Tsegeria Embaye, Kendra Turk, Ray Lee, Robert C. Vrijenhoek Aug 2005

Evolutionary Innovation: A Bone-Eating Marine Symbiosis, Shana K. Goffredi, Victoria J. Orphan, Greg W. Rouse, Linda Jahnke, Tsegeria Embaye, Kendra Turk, Ray Lee, Robert C. Vrijenhoek

Shana Goffredi

Symbiotic associations between microbes and invertebrates have resulted in some of the most unusual physiological and morphological adaptations that have evolved in the animal world. We document a new symbiosis between marine polychaetes of the genus Osedax and members of the bacterial group Oceanospirillales, known for heterotrophic degradation of complex organic compounds. These organisms were discovered living on the carcass of a grey whale at 2891 m depth in Monterey Canyon, off the coast of California. The mouthless and gutless worms are unique in their morphological specializations used to obtain nutrition from decomposing mammalian bones. Adult worms possess elaborate posterior …


Osedax: Bone-Eating Marine Worms With Dwarf Males, G W. Rouse, Shana K. Goffredi, R C. Vrijenhoek Jul 2004

Osedax: Bone-Eating Marine Worms With Dwarf Males, G W. Rouse, Shana K. Goffredi, R C. Vrijenhoek

Shana Goffredi

We describe a new genus, Osedax, and two new species of annelids with females that consume the bones of dead whales via ramifying roots. Molecular and morphological evidence revealed that Osedax belongs to the Siboglinidae, which includes pogonophoran and vestimentiferan worms from deep-sea vents, seeps, and anoxic basins. Osedax has skewed sex ratios with numerous dwarf (paedomorphic) males that live in the tubes of females. DNA sequences reveal that the two Osedax species diverged about 42 million years ago and currently maintain large populations ranging from 105 to 106 adult females.


Novel Forms Of Structural Integration Between Microbes And A Vent Gastropod From The Indian Ocean, Shana K. Goffredi, Anders Waren, Victoria J. Orphan, Cindy L. Van Dover, Robert C. Vrijenhoek Apr 2004

Novel Forms Of Structural Integration Between Microbes And A Vent Gastropod From The Indian Ocean, Shana K. Goffredi, Anders Waren, Victoria J. Orphan, Cindy L. Van Dover, Robert C. Vrijenhoek

Shana Goffredi

Here we describe novel forms of structural integration between endo- and episymbiotic microbes and an unusual new species of snail from hydrothermal vents in the Indian Ocean. The snail houses a dense population of γ-proteobacteria within the cells of its greatly enlarged esophageal gland. This tissue setting differs from that of all other vent mollusks, which harbor sulfur-oxidizing endosymbionts in their gills. The significantly reduced digestive tract, the isotopic signatures of the snail tissues, and the presence of internal bacteria suggest a dependence on chemoautotrophy for nutrition. Most notably, this snail is unique in having a dense coat of mineralized …


Evolutionary Relationships Of Deep-Sea Vent And Cold Seep Clams, Shana Goffredi, L A. Hurtado, S Hallam, R C. Vrijenhoek Dec 2002

Evolutionary Relationships Of Deep-Sea Vent And Cold Seep Clams, Shana Goffredi, L A. Hurtado, S Hallam, R C. Vrijenhoek

Shana Goffredi

Phylogenetic relationships among vesicomyid clams (Bivalvia: Vesicomyidae) and their placement within the order Heterodonta were examined using mitochondrial encoded cytochrome oxidase subunit I (COI) DNA sequences. The presently analyzed vesicomyids represent a recent monophyletic radiation that probably occurred within the Cenozoic. Nucleotide phylogenetic analyses resolved discrete clades that were consistent with currently recognized species: Calyptogena magnifica, C. ponderosa, Ectenagena extenta, C. phaseoliformis, Vesicomya cordata, Calyptogena n. sp. (Gulf of Mexico), C. kaikoi, C. nautilei, C. solidissima and C. soyoae (Type-A). However, specimens variously identified as: V. gigas, C. kilmeri, C. pacifica, and V. lepta comprised two “species complexes”, each composed …