Design and use of a new primer pair for the characterization of the cyanobacteria Synechococcus and Prochlorococcus communities targeting petB gene through metabarcoding approaches.

During the last years, the application of next-generation sequencing (NGS) technologies to search for specific genetic markers has become a crucial method for the characterization of microbial communities. Illumina MiSeq, likely the most widespread NGS platform for metabarcoding experiments and taxonomic classification, allows processing shorter reads than the classical SANGER sequencing method and therefore requires specific primer pairs that produce shorter amplicons. Specifically, for the analysis of the commonly studied Prochlorococcus and Synechococcus communities, the petB marker gene has recently stood out as able to provide deep coverage to determine the microdiversity of the community.. However, current petB primer set produce a 597 bp amplicon that is not suitable for MiSeq chemistry. Here, we designed and tested a petB primer pair that targets both Prochlorococcus and Synechococcus communities producing an appropriate amplicon to be used with state-of-the-art Illumina MiSeq. This new primer set allows the classification of both groups to a low taxonomic level and is therefore suitable for high throughput experiments using MiSeq technologies, therefore constituting a useful, novel tool to facilitate further studies on Prochlorococcus and Synechococcus communities. • This work describes the de novo design of a Prochlorococcus and Synechococcus-specific petB primer pair, allowing the characterization of both populations to a low taxonomic level. • This primer pair is suitable for widespread Illumina MiSeq sequencing technologies. • petB was confirmed as an adequate target for the characterization of both picocyanobacteria.