Molecular phylogenetic and diversity analysis of protistan microplankton based on 18S rRNA gene sequences

Abstract

Most of the protistan microplankton can be identified to species level based on the 18S rRNA gene sequences generated by previous primer sets. However, these primer sets amplify the 18S rRNA genes of not only protistan microplankton but also metazoan species, which can sometimes be abundant in field samples and thereby hampering a comprehensive analysis of the protistan microplankton. Recently, we introduced newly designed PCR primer sets and a protocol that is able to amplify a broad range of protistan microplankton taxa without any amplification of metazoan species. These primers and the protocol were evaluated a community analysis of protistan microplankton in Sagami-Bay and in the Kuroshio Current. In total, 55 genera of protistan microplankton were detected. This method could be beneficial for rapid analyses of large portion of the protistan microplankton community in various aquatic environments.