Elizabeth Wilbanks | University of California, Santa Barbara (original) (raw)

Elizabeth Wilbanks

Uploads

Papers by Elizabeth Wilbanks

Research paper thumbnail of The Green Berry Consortia of the Sippewissett Salt Marsh: Millimeter-Sized Aggregates of Diazotrophic Unicellular Cyanobacteria

Frontiers in Microbiology, 2017

Microbial interactions driving key biogeochemical fluxes often occur within multispecies consorti... more Microbial interactions driving key biogeochemical fluxes often occur within multispecies consortia that form spatially heterogeneous microenvironments. Here, we describe the " green berry " consortia of the Sippewissett salt marsh (Falmouth, MA, United States): millimeter-sized aggregates dominated by an uncultured, diazotrophic unicellular cyanobacterium of the order Chroococcales (termed GB-CYN1). We show that GB-CYN1 is closely related to Crocosphaera watsonii (UCYN-B) and " Candidatus Atelocyanobacterium thalassa " (UCYN-A), two groups of unicellular diazotrophic cyanobacteria that play an important role in marine primary production. Other green berry consortium members include pennate diatoms and putative heterotrophic bacteria from the Alphaproteobacteria and Bacteroidetes. Tight coupling was observed between photosynthetic oxygen production and heterotrophic respiration. When illuminated, the green berries became supersaturated with oxygen. From the metagenome, we observed that GB-CYN1 encodes photosystem II genes and thus has the metabolic potential for oxygen production unlike UCYN-A. In darkness, respiratory activity rapidly depleted oxygen creating anoxia within the aggregates. Metagenomic data revealed a suite of nitrogen fixation genes encoded by GB-CYN1, and nitrogenase activity was confirmed at the whole-aggregate level by acetylene reduction assays. Metagenome reads homologous to marker genes for denitrification were observed and suggest that heterotrophic denitrifiers might co-occur in the green berries, although the physiology and activity of facultative anaerobes in these aggregates remains uncharacterized. Nitrogen fixation in the surface ocean was long thought to be driven by filamentous cyanobacterial aggregates, though recent work has demonstrated the importance of unicellular diazotrophic cyanobacteria (UCYN) from the order Chroococcales.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Microscale sulfur cycling in the phototrophic pink berry consortia of the Sippewissett Salt Marsh

Environmental Microbiology, 2014

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Candidatus Frankia Datiscae Dg1, the Actinobacterial Microsymbiont of Datisca glomerata, Expresses the Canonical nod Genes nodABC in Symbiosis with Its Host Plant

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Sequencing of Seven Haloarchaeal Genomes Reveals Patterns of Genomic Flux

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A Monte Carlo-based framework enhances the discovery and interpretation of regulatory sequence motifs

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A workflow for genome-wide mapping of archaeal transcription factors with ChIP-seq

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Evaluation of Algorithm Performance in ChIP-Seq Peak Detection

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The Green Berry Consortia of the Sippewissett Salt Marsh: Millimeter-Sized Aggregates of Diazotrophic Unicellular Cyanobacteria

Frontiers in Microbiology, 2017

Microbial interactions driving key biogeochemical fluxes often occur within multispecies consorti... more Microbial interactions driving key biogeochemical fluxes often occur within multispecies consortia that form spatially heterogeneous microenvironments. Here, we describe the " green berry " consortia of the Sippewissett salt marsh (Falmouth, MA, United States): millimeter-sized aggregates dominated by an uncultured, diazotrophic unicellular cyanobacterium of the order Chroococcales (termed GB-CYN1). We show that GB-CYN1 is closely related to Crocosphaera watsonii (UCYN-B) and " Candidatus Atelocyanobacterium thalassa " (UCYN-A), two groups of unicellular diazotrophic cyanobacteria that play an important role in marine primary production. Other green berry consortium members include pennate diatoms and putative heterotrophic bacteria from the Alphaproteobacteria and Bacteroidetes. Tight coupling was observed between photosynthetic oxygen production and heterotrophic respiration. When illuminated, the green berries became supersaturated with oxygen. From the metagenome, we observed that GB-CYN1 encodes photosystem II genes and thus has the metabolic potential for oxygen production unlike UCYN-A. In darkness, respiratory activity rapidly depleted oxygen creating anoxia within the aggregates. Metagenomic data revealed a suite of nitrogen fixation genes encoded by GB-CYN1, and nitrogenase activity was confirmed at the whole-aggregate level by acetylene reduction assays. Metagenome reads homologous to marker genes for denitrification were observed and suggest that heterotrophic denitrifiers might co-occur in the green berries, although the physiology and activity of facultative anaerobes in these aggregates remains uncharacterized. Nitrogen fixation in the surface ocean was long thought to be driven by filamentous cyanobacterial aggregates, though recent work has demonstrated the importance of unicellular diazotrophic cyanobacteria (UCYN) from the order Chroococcales.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Microscale sulfur cycling in the phototrophic pink berry consortia of the Sippewissett Salt Marsh

Environmental Microbiology, 2014

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Candidatus Frankia Datiscae Dg1, the Actinobacterial Microsymbiont of Datisca glomerata, Expresses the Canonical nod Genes nodABC in Symbiosis with Its Host Plant

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Sequencing of Seven Haloarchaeal Genomes Reveals Patterns of Genomic Flux

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A Monte Carlo-based framework enhances the discovery and interpretation of regulatory sequence motifs

Bookmarks Related papers MentionsView impact

Research paper thumbnail of A workflow for genome-wide mapping of archaeal transcription factors with ChIP-seq

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Evaluation of Algorithm Performance in ChIP-Seq Peak Detection

Bookmarks Related papers MentionsView impact

Log In