Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates
An understanding of the distribution of colored dissolved organic matter (CDOM) in the oceans and its role in the global carbon cycle requires a better knowledge of the colored materials produced and consumed by marine phytoplankton and bacteria. In this work, we examined the net uptake and release of CDOM by a natural bacterial community growing on DOM derived from four phytoplankton species cultured under axenic conditions. Fluorescent humic-like substances exuded by phytoplankton (excitation/emission [Ex/Em] wavelength, 310 nm/392 nm; Coble's peak M) were utilized by bacteria in different proportions depending on the phytoplankton species of origin. Furthermore, bacteria produced humic-like substances that fluoresce at an Ex/Em wavelength of 340 nm/440 nm (Coble's peak C). Differences were also observed in the Ex/Em wavelengths of the protein-like materials (Coble's peak T) produced by phytoplankton and bacteria. The induced fluorescent emission of CDOM produced by prokaryotes was an order of magnitude higher than that of CDOM produced by eukaryotes. We have also examined the final compositions of the bacterial communities growing on the exudates, which differed markedly depending on the phytoplankton species of origin. Alteromonas and Roseobacter were dominant during all the incubations on Chaetoceros sp. and Prorocentrum minimum exudates, respectively. Alteromonas was the dominant group growing on Skeletonema costatum exudates during the exponential growth phase, but it was replaced by Roseobacter afterwards. On Micromonas pusilla exudates, Roseobacter was replaced by Bacteroidetes after the exponential growth phase. Our work shows that fluorescence excitation-emission matrices of CDOM can be a helpful tool for the identification of microbial sources of DOM in the marine environment, but further studies are necessary to explore the association of particular bacterial groups with specific fluorophores
Main Authors: | , , , , |
---|---|
Format: | artículo biblioteca |
Language: | English |
Published: |
American Society for Microbiology
2011
|
Online Access: | http://hdl.handle.net/10261/45173 |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
id |
dig-icm-es-10261-45173 |
---|---|
record_format |
koha |
spelling |
dig-icm-es-10261-451732019-03-07T16:26:35Z Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates Romera-Castillo, Cristina Sarmento, Hugo Álvarez-Salgado, Xosé Antón Gasol, Josep M. Marrasé, Cèlia An understanding of the distribution of colored dissolved organic matter (CDOM) in the oceans and its role in the global carbon cycle requires a better knowledge of the colored materials produced and consumed by marine phytoplankton and bacteria. In this work, we examined the net uptake and release of CDOM by a natural bacterial community growing on DOM derived from four phytoplankton species cultured under axenic conditions. Fluorescent humic-like substances exuded by phytoplankton (excitation/emission [Ex/Em] wavelength, 310 nm/392 nm; Coble's peak M) were utilized by bacteria in different proportions depending on the phytoplankton species of origin. Furthermore, bacteria produced humic-like substances that fluoresce at an Ex/Em wavelength of 340 nm/440 nm (Coble's peak C). Differences were also observed in the Ex/Em wavelengths of the protein-like materials (Coble's peak T) produced by phytoplankton and bacteria. The induced fluorescent emission of CDOM produced by prokaryotes was an order of magnitude higher than that of CDOM produced by eukaryotes. We have also examined the final compositions of the bacterial communities growing on the exudates, which differed markedly depending on the phytoplankton species of origin. Alteromonas and Roseobacter were dominant during all the incubations on Chaetoceros sp. and Prorocentrum minimum exudates, respectively. Alteromonas was the dominant group growing on Skeletonema costatum exudates during the exponential growth phase, but it was replaced by Roseobacter afterwards. On Micromonas pusilla exudates, Roseobacter was replaced by Bacteroidetes after the exponential growth phase. Our work shows that fluorescence excitation-emission matrices of CDOM can be a helpful tool for the identification of microbial sources of DOM in the marine environment, but further studies are necessary to explore the association of particular bacterial groups with specific fluorophores This work was supported by project SUMMER, grant number CTM2008–03309/MAR, C.R.-C. was funded by a I3P-CSIC predoctoral fellowship within the project MODIVUS, CTM2005-04795/MAR and H.S. benefited from fellowships from the Spanish ‘Ministerio de Educación y Ciencia’ (SB2006-0060 and JCI-2008-2727) and Portuguese ‘Fundação para a Ciência e a Tecnologia’ (FRH/BPD/34041/2006). Peer reviewed 2012-02-06T10:53:06Z 2012-02-06T10:53:06Z 2011 artículo http://purl.org/coar/resource_type/c_6501 Applied and Environmental Microbiology 77(21) : 7490-7498 (2011) 0099-2240 http://hdl.handle.net/10261/45173 10.1128/AEM.00200-11 1098-5336 en http.//dx.doi.org/10.1128/AEM.00200-11 open American Society for Microbiology |
institution |
ICM ES |
collection |
DSpace |
country |
España |
countrycode |
ES |
component |
Bibliográfico |
access |
En linea |
databasecode |
dig-icm-es |
tag |
biblioteca |
region |
Europa del Sur |
libraryname |
Biblioteca del ICM España |
language |
English |
description |
An understanding of the distribution of colored dissolved organic matter (CDOM) in the oceans and its role in the global carbon cycle requires a better knowledge of the colored materials produced and consumed by marine phytoplankton and bacteria. In this work, we examined the net uptake and release of CDOM by a natural bacterial community growing on DOM derived from four phytoplankton species cultured under axenic conditions. Fluorescent humic-like substances exuded by phytoplankton (excitation/emission [Ex/Em] wavelength, 310 nm/392 nm; Coble's peak M) were utilized by bacteria in different proportions depending on the phytoplankton species of origin. Furthermore, bacteria produced humic-like substances that fluoresce at an Ex/Em wavelength of 340 nm/440 nm (Coble's peak C). Differences were also observed in the Ex/Em wavelengths of the protein-like materials (Coble's peak T) produced by phytoplankton and bacteria. The induced fluorescent emission of CDOM produced by prokaryotes was an order of magnitude higher than that of CDOM produced by eukaryotes. We have also examined the final compositions of the bacterial communities growing on the exudates, which differed markedly depending on the phytoplankton species of origin. Alteromonas and Roseobacter were dominant during all the incubations on Chaetoceros sp. and Prorocentrum minimum exudates, respectively. Alteromonas was the dominant group growing on Skeletonema costatum exudates during the exponential growth phase, but it was replaced by Roseobacter afterwards. On Micromonas pusilla exudates, Roseobacter was replaced by Bacteroidetes after the exponential growth phase. Our work shows that fluorescence excitation-emission matrices of CDOM can be a helpful tool for the identification of microbial sources of DOM in the marine environment, but further studies are necessary to explore the association of particular bacterial groups with specific fluorophores |
format |
artículo |
author |
Romera-Castillo, Cristina Sarmento, Hugo Álvarez-Salgado, Xosé Antón Gasol, Josep M. Marrasé, Cèlia |
spellingShingle |
Romera-Castillo, Cristina Sarmento, Hugo Álvarez-Salgado, Xosé Antón Gasol, Josep M. Marrasé, Cèlia Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates |
author_facet |
Romera-Castillo, Cristina Sarmento, Hugo Álvarez-Salgado, Xosé Antón Gasol, Josep M. Marrasé, Cèlia |
author_sort |
Romera-Castillo, Cristina |
title |
Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates |
title_short |
Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates |
title_full |
Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates |
title_fullStr |
Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates |
title_full_unstemmed |
Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates |
title_sort |
net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates |
publisher |
American Society for Microbiology |
publishDate |
2011 |
url |
http://hdl.handle.net/10261/45173 |
work_keys_str_mv |
AT romeracastillocristina netproductionandconsumptionoffluorescentcoloreddissolvedorganicmatterbynaturalbacterialassemblagesgrowingonmarinephytoplanktonexudates AT sarmentohugo netproductionandconsumptionoffluorescentcoloreddissolvedorganicmatterbynaturalbacterialassemblagesgrowingonmarinephytoplanktonexudates AT alvarezsalgadoxoseanton netproductionandconsumptionoffluorescentcoloreddissolvedorganicmatterbynaturalbacterialassemblagesgrowingonmarinephytoplanktonexudates AT gasoljosepm netproductionandconsumptionoffluorescentcoloreddissolvedorganicmatterbynaturalbacterialassemblagesgrowingonmarinephytoplanktonexudates AT marrasecelia netproductionandconsumptionoffluorescentcoloreddissolvedorganicmatterbynaturalbacterialassemblagesgrowingonmarinephytoplanktonexudates |
_version_ |
1777665819446083584 |