Dataset Information

Respiratory succession and community succession of bacterioplankton in seasonally anoxic estuarine waters.

ABSTRACT: Anoxia occurs in bottom waters of stratified estuaries when respiratory consumption of oxygen, primarily by bacteria, outpaces atmospheric and photosynthetic reoxygenation. Once water becomes anoxic, bacterioplankton must change their metabolism to some form of anaerobic respiration. Analysis of redox chemistry in water samples spanning the oxycline of Chesapeake Bay during the summer of 2004 suggested that there was a succession of respiratory metabolism following the loss of oxygen. Bacterial community doubling time, calculated from bacterial abundance (direct counts) and production (anaerobic leucine incorporation), ranged from 0.36 to 0.75 day and was always much shorter than estimates of the time that the bottom water was anoxic (18 to 44 days), indicating that there was adequate time for bacterial community composition to shift in response to changing redox conditions. However, community composition (as determined by PCR-denaturing gradient gel electrophoresis analysis of 16S rRNA genes) in anoxic waters was very similar to that in surface waters in June when nitrate respiration was apparent in the water column and only partially shifted away from the composition of the surface community after nitrate was depleted. Anoxic water communities did not change dramatically until August, when sulfate respiration appeared to dominate. Surface water populations that remained dominant in anoxic waters were Synechococcus sp., Gammaproteobacteria in the SAR86 clade, and Alphaproteobacteria relatives of Pelagibacter ubique, including a putative estuarine-specific Pelagibacter cluster. Populations that developed in anoxic water were most similar (<92% similarity) to uncultivated Firmicutes, uncultivated Bacteroidetes, Gammaproteobacteria in the genus Thioalcalovibrio, and the uncultivated SAR406 cluster. These results indicate that typical estuarine bacterioplankton switch to anaerobic metabolism under anoxic conditions but are ultimately replaced by different organisms under sulfidic conditions.

SUBMITTER: Crump BC

PROVIDER: S-EPMC2074974 | biostudies-literature | 2007 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Respiratory succession and community succession of bacterioplankton in seasonally anoxic estuarine waters.

Crump Byron C BC Peranteau Cherie C Beckingham Barbara B Cornwell Jeffrey C JC

Applied and environmental microbiology 20070831 21

Anoxia occurs in bottom waters of stratified estuaries when respiratory consumption of oxygen, primarily by bacteria, outpaces atmospheric and photosynthetic reoxygenation. Once water becomes anoxic, bacterioplankton must change their metabolism to some form of anaerobic respiration. Analysis of redox chemistry in water samples spanning the oxycline of Chesapeake Bay during the summer of 2004 suggested that there was a succession of respiratory metabolism following the loss of oxygen. Bacterial ...[more]

PMID: 17766441

Similar Datasets

Project description:Caves are often assumed to be static environments separated from weather changes experienced on the surface. The high humidity and stability of these subterranean environments make them attractive to many different organisms including microbes such as bacteria and protists. Cave waters generally originate from the surface, may be filtered by overlying soils, can accumulate in interstitial epikarst zones underground, and emerge in caves as streams, pools and droplets on speleothems. Water movement is the primary architect of karst caves, and depending on the hydrologic connectivity between surface and subsurface, is the most likely medium for the introduction of microbes to caves. Recently published metabarcoding surveys of karst cave soils and speleothems have suggested that the vast majority of bacteria residing in these habitats do not occur on the surface, calling into question the role of microbial transport by surface waters. The purpose of this study was to use metabarcoding to monitor the aquatic prokaryotic microbiome of a cave for 1 year, conduct longitudinal analyses of the cave's aquatic bacterioplankton, and compare it to nearby surface water. Water samples were collected from two locations inside Panel Cave in Natural Tunnel State Park in Duffield, VA and two locations outside of the cave. Of the two cave locations, one was fed by groundwater and drip water and the other by infiltrating surface water. A total of 1,854 distinct prokaryotic ASVs were detected from cave samples and 245 (13.1%) were not found in surface samples. PCo analysis demonstrated a marginal delineation between two cave sample sites and between cave and surface microbiomes suggesting the aquatic bacterioplankton in a karst cave is much more similar to surface microbes than reported from speleothems and soils. Most surprisingly, there was a cave microbe population and diversity bloom in the fall months whereas biodiversity remained relatively steady on the surface. The cave microbiome was more similar to the surface before the bloom than during and afterwards. This event demonstrates that large influxes of bacteria and particulate organic matter can enter the cave from either the surface or interstitial zones and the divergence of the cave microbiome from the surface demonstrates movement of microbes from the epikarst zones into the cave.

Dataset Information

Respiratory succession and community succession of bacterioplankton in seasonally anoxic estuarine waters.

Publications

Respiratory succession and community succession of bacterioplankton in seasonally anoxic estuarine waters.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets