Symbiotic ß-proteobacteria beyond legumes: Burkholderia in Rubiaceae.
Symbiotic ß-proteobacteria not only occur in root nodules of legumes but are also found in leaves of certain Rubiaceae. The discovery of bacteria in plants formerly not implicated in endosymbiosis suggests a wider occurrence of plant-microbe interactions. Several ß-proteobacteria of the genus Burkholderia are detected in close association with tropical plants. This interaction has occurred three times independently, which suggest a recent and open plant-bacteria association. The presence or absence of Burkholderia endophytes is consistent on genus level and therefore implies a predictive value for the discovery of bacteria. Only a single Burkholderia species is found in association with a given plant species. However, the endophyte species are promiscuous and can be found in association with several plant species. Most of the endophytes are part of the plant-associated beneficial and environmental group, but others are closely related to B. glathei. This soil bacteria, together with related nodulating and non-nodulating endophytes, is therefore transferred to a newly defined and larger PBE group within the genus Burkholderia.
Plant Conservation and Population Biology, KU Leuven, Leuven, Belgium. brecht.verstraete@bio.kuleuven.be
Brecht
B
Verstraete
Steven
S
Janssens
Erik
E
Smets
Steven
S
Dessein
D020562:Betaproteobacteria / Q000145:classification* / Q000235:genetics / Q000648:ultrastructure; D019117:Burkholderia / Q000145:classification / Q000235:genetics / Q000648:ultrastructure; D060026:Endophytes / Q000145:classification / Q000235:genetics; D007887:Fabaceae / Q000382:microbiology*; D010802:Phylogeny; D018515:Plant Leaves / Q000382:microbiology / Q000648:ultrastructure; D019666:Rubiaceae / Q000382:microbiology; D013559:Symbiosis