ORPER: a workflow for constrained SSU rRNA phylogenies

The continuous increase of sequenced genomes in public repositories makes the choice of interesting bacterial strains for future sequencing projects evermore complicated, as it is difficult to estimate the redundancy between these strains and the already available genomes. Therefore, we developed the Nextflow workflow "ORPER" (containerized in Singularity), which allows determining the phylogenetic position of a collection of organisms in the genomic landscape. ORPER constrains the phylogenetic placement of SSU (16S) rRNA sequences in a multilocus reference tree based on ribosomal protein genes extracted from public genomes. We demonstrate the utility of ORPER on the Cyanobacteria phylum, by placing 152 strains of the BCCM/ULC collection.