Molecular analysis of photosynthetic picoeukaryote community structure along an Arabian Sea transect

• DOI: 10.4319/lo.2006.51.6.2502
• Publication Date: 2010-07-01T18:00:43Z
• Authors: Nicholas J. Fuller; Glen A. Tarran; Denise G. Cummings; E. Malcolm S. Woo...; Karen M. Orcutt; Marian Yallop; Florence Le Gall; David J. Scanlan
• Keywords: 0301 basic medicine; 03 medical and health sciences; 14. Life underwater

We developed oligonucleotide probes, based on plastid 16S ribosomal DNA (rDNA) sequences, to target 10 different algal classes (Chlorarachniophyceae, Chrysophyceae, Cryptophyceae, Eustigmatophyceae, Pavlovophyceae, Pelagophyceae, Pinguiophyceae, Prasinophyceae [clade VI], Prymnesiophyceae, and Trebouxiophyceae), for use with dot blot hybridization technology. These class‐specific probes were then used investigate the community structure of photosynthetic picoeukaryotes (≪3 µm) along a transect in Arabian Sea during September 2001, using rDNA polymerase chain reaction amplicons. The ranged from oligotrophic open‐ocean waters, just south Equator, through mesotrophic eutrophic waters toward north coast Oman, crossing region monsoonal upwelling off Omani northeast coast. Photosynthetic surface‐mixed layer (SML) deep chlorophyll maximum 1.0 x 3 cells mL ‐1 southern almost 30 at upwelling. Chrysophytes abundant most throughout much euphotic zone. Prymnesiophytes surface transect. By contrast, trebouxiophytes confined deeper below SML. Pelagophytes found that more mesotrophic, whereas cryptophytes only detected nutrient‐rich northern end transect, between depths 20‐30 m. Pinguiophytes also detected, but warm Oman. Chlorarachniophytes, eustigmatophytes, pavlovophytes, clade VI prasinophytes essentially detection limits entire