Microbial diversity in a Pacific Ocean transect from the Arctic to Antarctic circles

AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials AME 41:91-102 (2005) - doi:10.3354/ame041091 Microbial diversity in a Pacific Ocean transect from the Arctic to Antarctic circles Amy J. Baldwin1, Joseph A. Moss1, Joseph D. Pakulski1, Phillipe Catala2, Fabien Joux2, Wade H. Jeffrey1, * 1Center for Environmental Diagnostics and Bioremediation, University of West Florida, Building 58, 11000 University Parkway, Pensacola, Florida 32514 (850) 474-2472, USA 2Observatoire Océanologique de Banyuls, Laboratoire d'Océanographie Biologique, Université Pierre et Marie Curie, CNRS UMR7621, BP 44, 66651 Banyuls-sur-Mer Cedex, France *Corresponding author. Email: wjeffrey@uwf.edu ABSTRACT: Microbial diversity in surface waters was examined along a ~15400 km transect of the Pacific Ocean from 70°N to 68°S latitude between late August and early November 2003. Comparative microbial diversity was determined using terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR amplified 16S and 18S rDNA restriction digested with CfoI and MspI. Bacterial numbers and total chlorophyll were greatest at higher latitudes in both hemispheres, with a smaller peak in equatorial waters. Flow cytometry analysis indicated a strong peak in Prochlorococcus from approximately 30°N to 30°S. Richness at each station was relatively low, with ~11 prokaryotic peaks per sample and ~12 eukaryotic peaks per community. Overall, prokaryotic populations appeared more diverse, with 181 total terminal restriction fragments (T-RFs) generated, while eukaryotic populations produced a total of 135 T-RFs. Prokaryotic and eukaryotic similarity dendrograms revealed 4 distinct cluster groups relating to regions sub-Arctic/Arctic, temperate, tropical and sub-Antarctic/Antarctic. T-RFLP patterns suggest that microbial communities may be influenced by ambient water temperature, with mid-latitudinal and equatorial communities more similar in composition to each other than to cold water communities. Global distribution of prokaryotic communities revealed an average inter-group similarity of ~52%, while eukaryotic communities showed ~51% similarity, implying that Pacific planktonic communities appear to be fairly homogenous in composition. Several T-RFs were ubiquitously distributed and contributed significantly to each cluster group, while several T-RFs were observed to be endemic to particular oceanic regions. Within-group similarities of >70% were attributed to 12–14 T-RFs and 8–11 T-RFs in prokaryotic and eukaryotic profiles, respectively, suggesting that a small number of phylogenetic groups were responsible for each cluster group. KEY WORDS: Microbial diversity · Pacific Ocean · T-RFLP · 16S rDNA · 18S rDNA · Biogeographical distribution Full text in pdf format PreviousExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in AME Vol. 41, No. 1. Online publication date: November 11, 2005 Print ISSN: 0948-3055; Online ISSN: 1616-1564 Copyright © 2005 Inter-Research.