Separate Origins of Ice-Binding Proteins in Antarctic Chlamydomonas Species
The green alga Chlamydomonas raudensis is an important primary producer in a number of ice-covered lakes and ponds in Antarctica. A C. raudensis isolate (UWO241) from Lake Bonney in the McMurdo Dry Valleys, like many other Antarctic algae, was found to secrete ice-binding proteins (IBPs), which appe...
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ftpubmed:oai:pubmedcentral.nih.gov:3594216 2023-05-15T14:05:20+02:00 Separate Origins of Ice-Binding Proteins in Antarctic Chlamydomonas Species Raymond, James A. Morgan-Kiss, Rachael 2013-03-11 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3594216 http://www.ncbi.nlm.nih.gov/pubmed/23536869 https://doi.org/10.1371/journal.pone.0059186 en eng Public Library of Science http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3594216 http://www.ncbi.nlm.nih.gov/pubmed/23536869 http://dx.doi.org/10.1371/journal.pone.0059186 This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. CC-BY Research Article Text 2013 ftpubmed https://doi.org/10.1371/journal.pone.0059186 2013-09-04T20:58:23Z The green alga Chlamydomonas raudensis is an important primary producer in a number of ice-covered lakes and ponds in Antarctica. A C. raudensis isolate (UWO241) from Lake Bonney in the McMurdo Dry Valleys, like many other Antarctic algae, was found to secrete ice-binding proteins (IBPs), which appear to be essential for survival in icy environments. The IBPs of several Antarctic algae (diatoms, a prymesiophyte, and a prasinophyte) are similar to each other (here designated as type I IBPs) and have been proposed to have bacterial origins. Other IBPs (type II IBPs) that bear no resemblance to type I IBPs, have been found in the Antarctic Chlamydomonas sp. CCMP681, a putative snow alga, raising the possibility that chlamydomonad IBPs developed separately from the IBPs of other algae. To test this idea, we obtained the IBP sequences of C. raudensis UWO241 by sequencing the transcriptome. A large number of transcripts revealed no sequences resembling type II IBPs. Instead, many isoforms resembling type I IBPs were found, and these most closely matched a hypothetical protein from the bacterium Stigmatella aurantiaca. The sequences were confirmed to encode IBPs by the activity of a recombinant protein and by the matching of predicted and observed isoelectric points and molecular weights. Furthermore, a mesophilic sister species, C. raudensis SAG49.72, showed no ice-binding activity or PCR products from UWO241 IBP primers. These results confirm that algal IBPs are required for survival in icy habitats and demonstrate that they have diverse origins that are unrelated to the taxonomic positions of the algae. Last, we show that the C. raudensis UWO241 IBPs can change the structure of ice in a way that could increase the survivability of cells trapped in the ice. Text Antarc* Antarctic Antarctica McMurdo Dry Valleys PubMed Central (PMC) Antarctic Bonney ENVELOPE(162.417,162.417,-77.717,-77.717) Lake Bonney ENVELOPE(-25.588,-25.588,-80.361,-80.361) McMurdo Dry Valleys The Antarctic PLoS ONE 8 3 e59186 |
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Research Article Raymond, James A. Morgan-Kiss, Rachael Separate Origins of Ice-Binding Proteins in Antarctic Chlamydomonas Species |
topic_facet |
Research Article |
description |
The green alga Chlamydomonas raudensis is an important primary producer in a number of ice-covered lakes and ponds in Antarctica. A C. raudensis isolate (UWO241) from Lake Bonney in the McMurdo Dry Valleys, like many other Antarctic algae, was found to secrete ice-binding proteins (IBPs), which appear to be essential for survival in icy environments. The IBPs of several Antarctic algae (diatoms, a prymesiophyte, and a prasinophyte) are similar to each other (here designated as type I IBPs) and have been proposed to have bacterial origins. Other IBPs (type II IBPs) that bear no resemblance to type I IBPs, have been found in the Antarctic Chlamydomonas sp. CCMP681, a putative snow alga, raising the possibility that chlamydomonad IBPs developed separately from the IBPs of other algae. To test this idea, we obtained the IBP sequences of C. raudensis UWO241 by sequencing the transcriptome. A large number of transcripts revealed no sequences resembling type II IBPs. Instead, many isoforms resembling type I IBPs were found, and these most closely matched a hypothetical protein from the bacterium Stigmatella aurantiaca. The sequences were confirmed to encode IBPs by the activity of a recombinant protein and by the matching of predicted and observed isoelectric points and molecular weights. Furthermore, a mesophilic sister species, C. raudensis SAG49.72, showed no ice-binding activity or PCR products from UWO241 IBP primers. These results confirm that algal IBPs are required for survival in icy habitats and demonstrate that they have diverse origins that are unrelated to the taxonomic positions of the algae. Last, we show that the C. raudensis UWO241 IBPs can change the structure of ice in a way that could increase the survivability of cells trapped in the ice. |
format |
Text |
author |
Raymond, James A. Morgan-Kiss, Rachael |
author_facet |
Raymond, James A. Morgan-Kiss, Rachael |
author_sort |
Raymond, James A. |
title |
Separate Origins of Ice-Binding Proteins in Antarctic Chlamydomonas Species |
title_short |
Separate Origins of Ice-Binding Proteins in Antarctic Chlamydomonas Species |
title_full |
Separate Origins of Ice-Binding Proteins in Antarctic Chlamydomonas Species |
title_fullStr |
Separate Origins of Ice-Binding Proteins in Antarctic Chlamydomonas Species |
title_full_unstemmed |
Separate Origins of Ice-Binding Proteins in Antarctic Chlamydomonas Species |
title_sort |
separate origins of ice-binding proteins in antarctic chlamydomonas species |
publisher |
Public Library of Science |
publishDate |
2013 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3594216 http://www.ncbi.nlm.nih.gov/pubmed/23536869 https://doi.org/10.1371/journal.pone.0059186 |
long_lat |
ENVELOPE(162.417,162.417,-77.717,-77.717) ENVELOPE(-25.588,-25.588,-80.361,-80.361) |
geographic |
Antarctic Bonney Lake Bonney McMurdo Dry Valleys The Antarctic |
geographic_facet |
Antarctic Bonney Lake Bonney McMurdo Dry Valleys The Antarctic |
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/PMC3594216 http://www.ncbi.nlm.nih.gov/pubmed/23536869 http://dx.doi.org/10.1371/journal.pone.0059186 |
op_rights |
This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1371/journal.pone.0059186 |
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PLoS ONE |
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8 |
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3 |
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e59186 |
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1766277154294726656 |