Paraburkholderia atlanticasp. nov. andParaburkholderia franconissp. nov., two new nitrogen-fixing nodulating species isolated from Atlantic forest soils in Brazil

A polyphasic study was conducted with 11 strains trapped byMimosa pudicaandPhaseolus vulgarisgrown in soils of the Brazilian Atlantic Forest. In the phylogenetic analysis of the 16S rRNA gene, one clade of strains (Psp1) showed higher similarity withParaburkholderia piptadeniaeSTM7183(T)(99.6%), whereas the second (Psp6) was closely related toParaburkholderia tuberumSTM678(T)(99%). An MLSA (multilocus sequence analysis) with four (recA,gyrB,trpBandgltB) housekeeping genes placed both Psp1 and Psp6 strains in new clades, and BOX-PCR profiles indicated high intraspecific genetic diversity within each clade. Values of digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) of the whole genome sequences were of 56.9 and 94.4% between the Psp1 strain CNPSo 3157(T)andP. piptadeniae; and of 49.7% and 92.7% between the Psp6 strain CNPSo 3155(T)andP. tuberum, below the threshold for species delimitation. In thenodCanalysis, Psp1 strains clustered together withP. piptadeniae,while Psp6 did not group with any symbioticParaburkholderia. Other phenotypic, genotypic and symbiotic properties were evaluated. The polyphasic analysis supports that the strains represent two novel species, for which the namesParaburkholderia franconissp. nov. with type strain CNPSo 3157(T)(= ABIP 241, = LMG 31644) andParaburkholderia atlanticasp. nov. with type strain CNPSo 3155(T)(= ABIP 236, = LMG 31643) are proposed.