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Full-Text Articles in Life Sciences
Bromeliad Catchments As Habitats For Methanogenesis In Tropical Rainforest Canopies, Shana K. Goffredi, Gene E. Jang, Walter T. Woodside, William Ussler Iii
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
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
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
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 …
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
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 …
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
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 …