Cargando…

Recombination Does Not Hinder Formation or Detection of Ecological Species of Synechococcus Inhabiting a Hot Spring Cyanobacterial Mat

Recent studies of bacterial speciation have claimed to support the biological species concept—that reduced recombination is required for bacterial populations to diverge into species. This conclusion has been reached from the discovery that ecologically distinct clades show lower rates of recombinat...

Descripción completa

Detalles Bibliográficos
Autores principales: Melendrez, Melanie C., Becraft, Eric D., Wood, Jason M., Olsen, Millie T., Bryant, Donald A., Heidelberg, John F., Rusch, Douglas B., Cohan, Frederick M., Ward, David M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4712262/
https://www.ncbi.nlm.nih.gov/pubmed/26834710
http://dx.doi.org/10.3389/fmicb.2015.01540
_version_ 1782410032990650368
author Melendrez, Melanie C.
Becraft, Eric D.
Wood, Jason M.
Olsen, Millie T.
Bryant, Donald A.
Heidelberg, John F.
Rusch, Douglas B.
Cohan, Frederick M.
Ward, David M.
author_facet Melendrez, Melanie C.
Becraft, Eric D.
Wood, Jason M.
Olsen, Millie T.
Bryant, Donald A.
Heidelberg, John F.
Rusch, Douglas B.
Cohan, Frederick M.
Ward, David M.
author_sort Melendrez, Melanie C.
collection PubMed
description Recent studies of bacterial speciation have claimed to support the biological species concept—that reduced recombination is required for bacterial populations to diverge into species. This conclusion has been reached from the discovery that ecologically distinct clades show lower rates of recombination than that which occurs among closest relatives. However, these previous studies did not attempt to determine whether the more-rapidly recombining close relatives within the clades studied may also have diversified ecologically, without benefit of sexual isolation. Here we have measured the impact of recombination on ecological diversification within and between two ecologically distinct clades (A and B') of Synechococcus in a hot spring microbial mat in Yellowstone National Park, using a cultivation-free, multi-locus approach. Bacterial artificial chromosome (BAC) libraries were constructed from mat samples collected at 60°C and 65°C. Analysis of multiple linked loci near Synechococcus 16S rRNA genes showed little evidence of recombination between the A and B' lineages, but a record of recombination was apparent within each lineage. Recombination and mutation rates within each lineage were of similar magnitude, but recombination had a somewhat greater impact on sequence diversity than mutation, as also seen in many other bacteria and archaea. Despite recombination within the A and B' lineages, there was evidence of ecological diversification within each lineage. The algorithm Ecotype Simulation identified sequence clusters consistent with ecologically distinct populations (ecotypes), and several hypothesized ecotypes were distinct in their habitat associations and in their adaptations to different microenvironments. We conclude that sexual isolation is more likely to follow ecological divergence than to precede it. Thus, an ecology-based model of speciation appears more appropriate than the biological species concept for bacterial and archaeal diversification.
format Online
Article
Text
id pubmed-4712262
institution National Center for Biotechnology Information
language English
publishDate 2016
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-47122622016-01-29 Recombination Does Not Hinder Formation or Detection of Ecological Species of Synechococcus Inhabiting a Hot Spring Cyanobacterial Mat Melendrez, Melanie C. Becraft, Eric D. Wood, Jason M. Olsen, Millie T. Bryant, Donald A. Heidelberg, John F. Rusch, Douglas B. Cohan, Frederick M. Ward, David M. Front Microbiol Microbiology Recent studies of bacterial speciation have claimed to support the biological species concept—that reduced recombination is required for bacterial populations to diverge into species. This conclusion has been reached from the discovery that ecologically distinct clades show lower rates of recombination than that which occurs among closest relatives. However, these previous studies did not attempt to determine whether the more-rapidly recombining close relatives within the clades studied may also have diversified ecologically, without benefit of sexual isolation. Here we have measured the impact of recombination on ecological diversification within and between two ecologically distinct clades (A and B') of Synechococcus in a hot spring microbial mat in Yellowstone National Park, using a cultivation-free, multi-locus approach. Bacterial artificial chromosome (BAC) libraries were constructed from mat samples collected at 60°C and 65°C. Analysis of multiple linked loci near Synechococcus 16S rRNA genes showed little evidence of recombination between the A and B' lineages, but a record of recombination was apparent within each lineage. Recombination and mutation rates within each lineage were of similar magnitude, but recombination had a somewhat greater impact on sequence diversity than mutation, as also seen in many other bacteria and archaea. Despite recombination within the A and B' lineages, there was evidence of ecological diversification within each lineage. The algorithm Ecotype Simulation identified sequence clusters consistent with ecologically distinct populations (ecotypes), and several hypothesized ecotypes were distinct in their habitat associations and in their adaptations to different microenvironments. We conclude that sexual isolation is more likely to follow ecological divergence than to precede it. Thus, an ecology-based model of speciation appears more appropriate than the biological species concept for bacterial and archaeal diversification. Frontiers Media S.A. 2016-01-14 /pmc/articles/PMC4712262/ /pubmed/26834710 http://dx.doi.org/10.3389/fmicb.2015.01540 Text en Copyright © 2016 Melendrez, Becraft, Wood, Olsen, Bryant, Heidelberg, Rusch, Cohan and Ward. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Microbiology
Melendrez, Melanie C.
Becraft, Eric D.
Wood, Jason M.
Olsen, Millie T.
Bryant, Donald A.
Heidelberg, John F.
Rusch, Douglas B.
Cohan, Frederick M.
Ward, David M.
Recombination Does Not Hinder Formation or Detection of Ecological Species of Synechococcus Inhabiting a Hot Spring Cyanobacterial Mat
title Recombination Does Not Hinder Formation or Detection of Ecological Species of Synechococcus Inhabiting a Hot Spring Cyanobacterial Mat
title_full Recombination Does Not Hinder Formation or Detection of Ecological Species of Synechococcus Inhabiting a Hot Spring Cyanobacterial Mat
title_fullStr Recombination Does Not Hinder Formation or Detection of Ecological Species of Synechococcus Inhabiting a Hot Spring Cyanobacterial Mat
title_full_unstemmed Recombination Does Not Hinder Formation or Detection of Ecological Species of Synechococcus Inhabiting a Hot Spring Cyanobacterial Mat
title_short Recombination Does Not Hinder Formation or Detection of Ecological Species of Synechococcus Inhabiting a Hot Spring Cyanobacterial Mat
title_sort recombination does not hinder formation or detection of ecological species of synechococcus inhabiting a hot spring cyanobacterial mat
topic Microbiology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4712262/
https://www.ncbi.nlm.nih.gov/pubmed/26834710
http://dx.doi.org/10.3389/fmicb.2015.01540
work_keys_str_mv AT melendrezmelaniec recombinationdoesnothinderformationordetectionofecologicalspeciesofsynechococcusinhabitingahotspringcyanobacterialmat
AT becraftericd recombinationdoesnothinderformationordetectionofecologicalspeciesofsynechococcusinhabitingahotspringcyanobacterialmat
AT woodjasonm recombinationdoesnothinderformationordetectionofecologicalspeciesofsynechococcusinhabitingahotspringcyanobacterialmat
AT olsenmilliet recombinationdoesnothinderformationordetectionofecologicalspeciesofsynechococcusinhabitingahotspringcyanobacterialmat
AT bryantdonalda recombinationdoesnothinderformationordetectionofecologicalspeciesofsynechococcusinhabitingahotspringcyanobacterialmat
AT heidelbergjohnf recombinationdoesnothinderformationordetectionofecologicalspeciesofsynechococcusinhabitingahotspringcyanobacterialmat
AT ruschdouglasb recombinationdoesnothinderformationordetectionofecologicalspeciesofsynechococcusinhabitingahotspringcyanobacterialmat
AT cohanfrederickm recombinationdoesnothinderformationordetectionofecologicalspeciesofsynechococcusinhabitingahotspringcyanobacterialmat
AT warddavidm recombinationdoesnothinderformationordetectionofecologicalspeciesofsynechococcusinhabitingahotspringcyanobacterialmat