Identification of the bacterial endosymbionts in leaf galls of Psychotria (Rubiaceae, angiosperms) and proposal of 'Candidatus Burkholderia kirkii' sp. nov.

This paper reports the identification of bacterial endosymbionts inhabiting the leaf galls of Psychotria kirkii. A phylogenetic approach was used to reveal the identity of these as yet uncultivable bacterial endophytes. Based on the analysis of 16S rDNA sequences, evolutionary trees were constructed that place the endosymbiont in the genus Burkholderia. Low levels of sequence identity and rather large evolutionary distances to the closest validly named relatives indicate that these symbiotic bacteria represent a novel species. Until cultivation is successful or until more phenotypic data become available the provisional name 'Candidatus Burkholderia kirkii' sp. nov. is proposed.