29 June 2021
We performed a taxonomic and comparative genomics analysis of 67 novel Paraburkholderia isolates from forest soil. Phylogenetic analysis of the recA gene revealed that these isolates formed a coherent lineage within the genus Paraburkholderia that also included Paraburkholderia aspalathi, Paraburkholderia madseniana, Paraburkholderia sediminicola, Paraburkholderia caffeinilytica, Paraburkholderia solitsugae and Paraburkholderia elongata and four unidentified soil isolates from earlier studies. A phylogenomic analysis, along with orthoANIu and digital DNA–DNA hybridization calculations revealed that they represented four different species including three novel species and P. aspalathi. Functional genome annotation of the strains revealed several pathways for aromatic compound degradation and the presence of mono- and dioxygenases involved in the degradation of the lignin-derived compounds ferulic acid and p-coumaric acid. This co-occurrence of multiple Paraburkholderia strains and species with the capacity to degrade aromatic compounds in pristine forest soil is likely caused by the abundant presence of aromatic compounds in decomposing plant litter and may highlight a diversity in micro-habitats or be indicative of synergistic relationships. We propose to classify the isolates representing novel species as Paraburkholderia domus with LMG 31832 T (=CECT 30334) as the type strain, Paraburkholderia nemoris with LMG 31836 T (=CECT 30335) as the type strain and Paraburkholderia haematera with LMG 31837 T (=CECT 30336) as the type strain and provide an emended description of Paraburkholderia sediminicola Lim et al. 2008.