Legume-nodulating betaproteobacteria: diversity, host range and future prospects

TY - JOUR

T1 - Legume-nodulating betaproteobacteria

T2 - diversity, host range and future prospects

AU - Gyaneshwar, Prasad

AU - Hirsch, A.

AU - Moulin, Lionel

AU - Chen, Wen-Ming

AU - Elliott, Geoffrey N.

AU - Bontemps, Cyril

AU - Estrada de los Santos, Paulina

AU - Gross, Eduardo

AU - Sprent, Janet I.

AU - Young, Peter

AU - James, Euan K.

PY - 2011/11

Y1 - 2011/11

N2 - Rhizobia form specialized nodules on the roots of legumes (family Fabaceae) and fix nitrogen in exchange for carbon from the host plant. Although the majority of legumes form symbioses with members of genus Rhizobium and its relatives in class Alphaproteobacteria, some legumes, such as those in the large genus Mimosa, are nodulated pre- dominantly by betaproteobacteria in the genera Burkhold- eria and Cupriavidus. The principal centers of diversity of these bacteria are in central Brazil and South Africa. Mo- lecular phylogenetic studies have shown that betaproteo- bacteria have existed as legume symbionts for approxi- mately 50 million years, and that, although they have a common origin, the symbiosis genes in both subclasses have evolved separately since then. Additionally, some spe- cies of genus Burkholderia, such as B. phymatum, are highly promiscuous, effectively nodulating several impor- tant legumes, including common bean (Phaseolus vulgaris). In contrast to genus Burkholderia, only one species of ge- nus Cupriavidus (C. taiwanensis) has so far been shown to nodulate legumes. The recent availability of the genome sequences of C. taiwanensis, B. phymatum, and B. tuberum has paved the way for a more detailed analysis of the evolu- tionary and mechanistic differences between nodulating strains of alpha- and betaproteobacteria. Initial analyses of genome sequences have suggested that plant-associated Burkholderia spp. have lower G+C contents than Burkholderia spp. that are opportunistic human pathogens, thus supporting previous suggestions that the plant- and human-associated groups of Burkholderia actually belong in separate genera.

AB - Rhizobia form specialized nodules on the roots of legumes (family Fabaceae) and fix nitrogen in exchange for carbon from the host plant. Although the majority of legumes form symbioses with members of genus Rhizobium and its relatives in class Alphaproteobacteria, some legumes, such as those in the large genus Mimosa, are nodulated pre- dominantly by betaproteobacteria in the genera Burkhold- eria and Cupriavidus. The principal centers of diversity of these bacteria are in central Brazil and South Africa. Mo- lecular phylogenetic studies have shown that betaproteo- bacteria have existed as legume symbionts for approxi- mately 50 million years, and that, although they have a common origin, the symbiosis genes in both subclasses have evolved separately since then. Additionally, some spe- cies of genus Burkholderia, such as B. phymatum, are highly promiscuous, effectively nodulating several impor- tant legumes, including common bean (Phaseolus vulgaris). In contrast to genus Burkholderia, only one species of ge- nus Cupriavidus (C. taiwanensis) has so far been shown to nodulate legumes. The recent availability of the genome sequences of C. taiwanensis, B. phymatum, and B. tuberum has paved the way for a more detailed analysis of the evolu- tionary and mechanistic differences between nodulating strains of alpha- and betaproteobacteria. Initial analyses of genome sequences have suggested that plant-associated Burkholderia spp. have lower G+C contents than Burkholderia spp. that are opportunistic human pathogens, thus supporting previous suggestions that the plant- and human-associated groups of Burkholderia actually belong in separate genera.

UR - http://www.scopus.com/inward/record.url?scp=80054737011&partnerID=8YFLogxK

U2 - 10.1094/MPMI-06-11-0172

DO - 10.1094/MPMI-06-11-0172

M3 - Article

SN - 0894-0282

VL - 24

SP - 1276

EP - 1288

JO - MOLECULAR PLANT-MICROBE INTERACTIONS

JF - MOLECULAR PLANT-MICROBE INTERACTIONS

IS - 11

ER -