The University of Southampton
University of Southampton Institutional Repository

Molecular identification of picoplankton populations in contrasting waters of the Arabian Sea

Molecular identification of picoplankton populations in contrasting waters of the Arabian Sea
Molecular identification of picoplankton populations in contrasting waters of the Arabian Sea
The composition of picoplankton in the southern oligotrophic, northern mesotrophic waters and deep oxygen minimum zone (OMZ) of the Arabian Sea was determined by 16S ribosomal RNA gene cloning and fluorescence in situ hybridisation (FISH). It was hypothesised that the composition of the heterotrophic picoplankton would be different in these contrasting waters. To reduce the total diversity, cells were sorted by flow cytometry according to their scatter and DNA content before PCR amplification. The 16S rRNA clone libraries resulting from flow-sorted populations were different and often dominated by a small number of clades. Libraries from the Prochlorococcus-dominated southerly waters were dominated by sequences related to uncultured clusters of SAR11, SAR86 and Actinobacteria (HGC I). From surface waters of the Synechococcus-dominated northern part of the Arabian Sea, mostly sequences related to the uncultured gammaproteobacterial group ‘Svalbard’ and HGC I were retrieved. The clone libraries from the OMZ were also dominated by sequences falling in the clades SAR11 and SAR406, but included sequences related to those of sulfate-reducing (Desulfosarcina, Desulfofrigus) and sulfide-oxidising bacteria (endosymbionts of Riftia and Calyptogena). With a recently developed more sensitive FISH protocol approximately 60% of all DAPI stained cells could be identified by general probes as Bacteria, Cren- or Euryarchaeota in both provinces of the Arabian Sea; 40% remained undetected. On this level and on that of the major phylogenetic groups like Alpha- and Gammaproteobacteria only minor differences were detected by FISH. However, the composition of heterotrophic picoplankton clearly differed for the proteobacterial subgroups SAR86, SAR11 and SAR116. These were more abundant in the oligotrophic waters throughout the water column than in the mesotrophic surface waters and the OMZ. This supports our original hypothesis that the contrasting waters in the Arabian Sea harbor different heterotrophic picoplankton communities. In the future, FISH with a larger set of probes for more narrow phylogenetic groups will enable us to quantify these differences in more detail.
phylogenetic composition, Arabian Sea, Oxygen Minimum Zone, OMZ, fluorescence in situ hybridisation, Catalyzed Reporter Deposition (CARD)-FISH, oligonucleotide probes, flow cytometry
0948-3055
145-157
Fuchs, B.M.
1edd27c8-6b61-47f1-9c65-788d3fef9fd3
Woebken, D.
db0885b5-9ec2-4ad2-ae84-a69c12e60d8a
Zubkov, M.V.
b1dfb3a0-bcff-430c-9031-358a22b50743
Burkill, P.
b6c80c95-969e-4762-b7bc-230511eeaf71
Amann, R.
c56b595a-e2d2-43f4-b058-a34b5fcf05f8
Fuchs, B.M.
1edd27c8-6b61-47f1-9c65-788d3fef9fd3
Woebken, D.
db0885b5-9ec2-4ad2-ae84-a69c12e60d8a
Zubkov, M.V.
b1dfb3a0-bcff-430c-9031-358a22b50743
Burkill, P.
b6c80c95-969e-4762-b7bc-230511eeaf71
Amann, R.
c56b595a-e2d2-43f4-b058-a34b5fcf05f8

Fuchs, B.M., Woebken, D., Zubkov, M.V., Burkill, P. and Amann, R. (2005) Molecular identification of picoplankton populations in contrasting waters of the Arabian Sea. Aquatic Microbial Ecology, 39 (2), 145-157.

Record type: Article

Abstract

The composition of picoplankton in the southern oligotrophic, northern mesotrophic waters and deep oxygen minimum zone (OMZ) of the Arabian Sea was determined by 16S ribosomal RNA gene cloning and fluorescence in situ hybridisation (FISH). It was hypothesised that the composition of the heterotrophic picoplankton would be different in these contrasting waters. To reduce the total diversity, cells were sorted by flow cytometry according to their scatter and DNA content before PCR amplification. The 16S rRNA clone libraries resulting from flow-sorted populations were different and often dominated by a small number of clades. Libraries from the Prochlorococcus-dominated southerly waters were dominated by sequences related to uncultured clusters of SAR11, SAR86 and Actinobacteria (HGC I). From surface waters of the Synechococcus-dominated northern part of the Arabian Sea, mostly sequences related to the uncultured gammaproteobacterial group ‘Svalbard’ and HGC I were retrieved. The clone libraries from the OMZ were also dominated by sequences falling in the clades SAR11 and SAR406, but included sequences related to those of sulfate-reducing (Desulfosarcina, Desulfofrigus) and sulfide-oxidising bacteria (endosymbionts of Riftia and Calyptogena). With a recently developed more sensitive FISH protocol approximately 60% of all DAPI stained cells could be identified by general probes as Bacteria, Cren- or Euryarchaeota in both provinces of the Arabian Sea; 40% remained undetected. On this level and on that of the major phylogenetic groups like Alpha- and Gammaproteobacteria only minor differences were detected by FISH. However, the composition of heterotrophic picoplankton clearly differed for the proteobacterial subgroups SAR86, SAR11 and SAR116. These were more abundant in the oligotrophic waters throughout the water column than in the mesotrophic surface waters and the OMZ. This supports our original hypothesis that the contrasting waters in the Arabian Sea harbor different heterotrophic picoplankton communities. In the future, FISH with a larger set of probes for more narrow phylogenetic groups will enable us to quantify these differences in more detail.

This record has no associated files available for download.

More information

Published date: 2005
Keywords: phylogenetic composition, Arabian Sea, Oxygen Minimum Zone, OMZ, fluorescence in situ hybridisation, Catalyzed Reporter Deposition (CARD)-FISH, oligonucleotide probes, flow cytometry

Identifiers

Local EPrints ID: 16386
URI: http://eprints.soton.ac.uk/id/eprint/16386
ISSN: 0948-3055
PURE UUID: bcf53dc1-b277-468e-b200-535fefae3efb

Catalogue record

Date deposited: 02 Aug 2005
Last modified: 09 Jan 2022 06:04

Export record

Contributors

Author: B.M. Fuchs
Author: D. Woebken
Author: M.V. Zubkov
Author: P. Burkill
Author: R. Amann

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×