Dataset: SPOT Microbial Observatory Protist 18S rDNA TRFLP relative peak abundance data from 2014 (Bacterial, Archaeal, and Protistan Biodiversity project, Marine Viral Dynamics project, Mar. Microbial Communities project)

Dominant taxa within protistan assemblages were characterized by 18S rDNA-based TRFLP using Euk-A and Euk570-R primers for PCR and HaeIII for digestion (Countway et al., 2005; Vigil et al., 2009); fragments were analyzed on a Beckman CEQ 8000 (Brea, CA, USA). Fragments from Ostreococcus sp. and Phaeocystis globosa cultures were used as positive controls for calibrating and verifying fragment sizes. Protistan OTUs were identified from in silico digestion of 1341 18S rRNA gene sequences from October 2001 at SPOT (Kim et al., 2012). Unique fragment lengths were considered as individual OTUs. Relative abundance of each OTU was calculated by dividing a peak’s area by the total area within the monthly fingerprint. Protistan OTUs <0.5% of the community were removed from further analysis, and the remaining peaks were normalized by sample to determine relative abundance per month; each community thus totaled to 100%.

Relevant References:

* Chow CET, Kim DY, Sachdeva R, Caron DA, and Fuhrman JA. (2014). Top-down controls on bacterial community structure: microbial network analysis of bacteria, T4-like viruses and protists. ISME Journal, 8: 816-829

and

Brown MV, Schwalbach MS, Hewson I, Fuhrman JA.(2005). Coupling 16S-ITS rDNA clone libraries and automated ribosomal intergenic spacer analysis to show marine microbial diversity: development and application to a time series. Environ Microbiol 7: 1466–1479.

 Chow C-ET, Fuhrman JA. (2012). Seasonality and monthly dynamics of marine myovirus communities. Environ Microbiol 14: 2171–2183.

 Chow C-ET, Sachdeva R, Cram JA, Steele JA, Needham DM, Patel A et al. (2013). Temporal variability and coherence of euphotic zone bacterial communities over a decade in the Southern California Bight. ISME J; epub ahead of print 18 July 2013; doi:10.1038/ismej.2013.122.

 Countway PD, Gast RJ, Savai P, Caron DA. (2005). Protistan diversity estimates based on 18S rDNA from seawater incubations in the western north Atlantic1. J Eukaryot Microbiol 52: 95–106.

 Countway PD, Vigil PD, Schnetzer A, Moorthi SD, Caron DA. (2010). Seasonal analysis of protistan community structure and diversity at the USC Microbial Observatory (San Pedro Channel, North Pacific Ocean). Limnol Oceanogr 55: 2381–2396.

 Fisher MM, Triplett EW. (1999). Automated approach for ribosomal intergenic spacer analysis of microbial diversity and its application to freshwater bacterial communities. Appl Environ Microbiol 65: 4630–4636.