Microbial Mat Communities along an Oxygen Gradient in a Perennially Ice-Covered Antarctic Lake
Lake Fryxell is a perennially ice-covered lake in the McMurdo Dry Valleys, Antarctica, with a sharp oxycline in a water column that is density stabilized by a gradient in salt concentration. Dissolved oxygen falls from 20 mg liter−1 to undetectable over one vertical meter from 8.9- to 9.9-m depth. W...
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ftpubmed:oai:pubmedcentral.nih.gov:4711149 2023-05-15T13:58:02+02:00 Microbial Mat Communities along an Oxygen Gradient in a Perennially Ice-Covered Antarctic Lake Jungblut, Anne D. Hawes, Ian Mackey, Tyler J. Krusor, Megan Doran, Peter T. Sumner, Dawn Y. Eisen, Jonathan A. Hillman, Colin Goroncy, Alexander K. 2016-01-07 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4711149/ http://www.ncbi.nlm.nih.gov/pubmed/26567300 https://doi.org/10.1128/AEM.02699-15 en eng American Society for Microbiology http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4711149/ http://www.ncbi.nlm.nih.gov/pubmed/26567300 http://dx.doi.org/10.1128/AEM.02699-15 Copyright © 2016, American Society for Microbiology. All Rights Reserved. Environmental Microbiology Text 2016 ftpubmed https://doi.org/10.1128/AEM.02699-15 2016-07-10T00:01:47Z Lake Fryxell is a perennially ice-covered lake in the McMurdo Dry Valleys, Antarctica, with a sharp oxycline in a water column that is density stabilized by a gradient in salt concentration. Dissolved oxygen falls from 20 mg liter−1 to undetectable over one vertical meter from 8.9- to 9.9-m depth. We provide the first description of the benthic mat community that falls within this oxygen gradient on the sloping floor of the lake, using a combination of micro- and macroscopic morphological descriptions, pigment analysis, and 16S rRNA gene bacterial community analysis. Our work focused on three macroscopic mat morphologies that were associated with different parts of the oxygen gradient: (i) “cuspate pinnacles” in the upper hyperoxic zone, which displayed complex topography and were dominated by phycoerythrin-rich cyanobacteria attributable to the genus Leptolyngbya and a diverse but sparse assemblage of pennate diatoms; (ii) a less topographically complex “ridge-pit” mat located immediately above the oxic-anoxic transition containing Leptolyngbya and an increasing abundance of diatoms; and (iii) flat prostrate mats in the upper anoxic zone, dominated by a green cyanobacterium phylogenetically identified as Phormidium pseudopriestleyi and a single diatom, Diadesmis contenta. Zonation of bacteria was by lake depth and by depth into individual mats. Deeper mats had higher abundances of bacteriochlorophylls and anoxygenic phototrophs, including Chlorobi and Chloroflexi. This suggests that microbial communities form assemblages specific to niche-like locations. Mat morphologies, underpinned by cyanobacterial and diatom composition, are the result of local habitat conditions likely defined by irradiance and oxygen and sulfide concentrations. Text Antarc* Antarctic Antarctica McMurdo Dry Valleys PubMed Central (PMC) Antarctic Fryxell ENVELOPE(163.183,163.183,-77.617,-77.617) Lake Fryxell ENVELOPE(163.183,163.183,-77.617,-77.617) McMurdo Dry Valleys Applied and Environmental Microbiology 82 2 620 630 |
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language |
English |
topic |
Environmental Microbiology |
spellingShingle |
Environmental Microbiology Jungblut, Anne D. Hawes, Ian Mackey, Tyler J. Krusor, Megan Doran, Peter T. Sumner, Dawn Y. Eisen, Jonathan A. Hillman, Colin Goroncy, Alexander K. Microbial Mat Communities along an Oxygen Gradient in a Perennially Ice-Covered Antarctic Lake |
topic_facet |
Environmental Microbiology |
description |
Lake Fryxell is a perennially ice-covered lake in the McMurdo Dry Valleys, Antarctica, with a sharp oxycline in a water column that is density stabilized by a gradient in salt concentration. Dissolved oxygen falls from 20 mg liter−1 to undetectable over one vertical meter from 8.9- to 9.9-m depth. We provide the first description of the benthic mat community that falls within this oxygen gradient on the sloping floor of the lake, using a combination of micro- and macroscopic morphological descriptions, pigment analysis, and 16S rRNA gene bacterial community analysis. Our work focused on three macroscopic mat morphologies that were associated with different parts of the oxygen gradient: (i) “cuspate pinnacles” in the upper hyperoxic zone, which displayed complex topography and were dominated by phycoerythrin-rich cyanobacteria attributable to the genus Leptolyngbya and a diverse but sparse assemblage of pennate diatoms; (ii) a less topographically complex “ridge-pit” mat located immediately above the oxic-anoxic transition containing Leptolyngbya and an increasing abundance of diatoms; and (iii) flat prostrate mats in the upper anoxic zone, dominated by a green cyanobacterium phylogenetically identified as Phormidium pseudopriestleyi and a single diatom, Diadesmis contenta. Zonation of bacteria was by lake depth and by depth into individual mats. Deeper mats had higher abundances of bacteriochlorophylls and anoxygenic phototrophs, including Chlorobi and Chloroflexi. This suggests that microbial communities form assemblages specific to niche-like locations. Mat morphologies, underpinned by cyanobacterial and diatom composition, are the result of local habitat conditions likely defined by irradiance and oxygen and sulfide concentrations. |
format |
Text |
author |
Jungblut, Anne D. Hawes, Ian Mackey, Tyler J. Krusor, Megan Doran, Peter T. Sumner, Dawn Y. Eisen, Jonathan A. Hillman, Colin Goroncy, Alexander K. |
author_facet |
Jungblut, Anne D. Hawes, Ian Mackey, Tyler J. Krusor, Megan Doran, Peter T. Sumner, Dawn Y. Eisen, Jonathan A. Hillman, Colin Goroncy, Alexander K. |
author_sort |
Jungblut, Anne D. |
title |
Microbial Mat Communities along an Oxygen Gradient in a Perennially Ice-Covered Antarctic Lake |
title_short |
Microbial Mat Communities along an Oxygen Gradient in a Perennially Ice-Covered Antarctic Lake |
title_full |
Microbial Mat Communities along an Oxygen Gradient in a Perennially Ice-Covered Antarctic Lake |
title_fullStr |
Microbial Mat Communities along an Oxygen Gradient in a Perennially Ice-Covered Antarctic Lake |
title_full_unstemmed |
Microbial Mat Communities along an Oxygen Gradient in a Perennially Ice-Covered Antarctic Lake |
title_sort |
microbial mat communities along an oxygen gradient in a perennially ice-covered antarctic lake |
publisher |
American Society for Microbiology |
publishDate |
2016 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4711149/ http://www.ncbi.nlm.nih.gov/pubmed/26567300 https://doi.org/10.1128/AEM.02699-15 |
long_lat |
ENVELOPE(163.183,163.183,-77.617,-77.617) ENVELOPE(163.183,163.183,-77.617,-77.617) |
geographic |
Antarctic Fryxell Lake Fryxell McMurdo Dry Valleys |
geographic_facet |
Antarctic Fryxell Lake Fryxell McMurdo Dry Valleys |
genre |
Antarc* Antarctic Antarctica McMurdo Dry Valleys |
genre_facet |
Antarc* Antarctic Antarctica McMurdo Dry Valleys |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4711149/ http://www.ncbi.nlm.nih.gov/pubmed/26567300 http://dx.doi.org/10.1128/AEM.02699-15 |
op_rights |
Copyright © 2016, American Society for Microbiology. All Rights Reserved. |
op_doi |
https://doi.org/10.1128/AEM.02699-15 |
container_title |
Applied and Environmental Microbiology |
container_volume |
82 |
container_issue |
2 |
container_start_page |
620 |
op_container_end_page |
630 |
_version_ |
1766266013637148672 |