Burkholderia dilworthii strain WSM3556(T) is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from an effective N2-fixing root nodule of Lebeckia ambigua collected near Grotto Bay Nature Reserve, in the Western Cape of South Africa, in October 2004. This plant persists in infertile and deep sandy soils with acidic pH, and is therefore an ideal candidate for a perennial based agriculture system in Western Australia. WSM3556(T) thus represents a potential inoculant quality strain for L. ambigua for which we describe the general features, together with genome sequence and annotation. The 7,679,067 bp high-quality permanent draft genome is arranged in 140 scaffolds of 141 contigs, contains 7,059 protein-coding genes and 64 RNA-only encoding genes, and is part of the GEBA-RNB project proposal.

Burkholderia sp. strain WSM4176 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from an effective N2-fixing root nodule of Lebeckia ambigua collected in Nieuwoudtville, Western Cape of South Africa, in October 2007. This plant persists in infertile, acidic and deep sandy soils, and is therefore an ideal candidate for a perennial based agriculture system in Western Australia. Here we describe the features of Burkholderia sp. strain WSM4176, which represents a potential inoculant quality strain for L. ambigua, together with sequence and annotation. The 9,065,247 bp high-quality-draft genome is arranged in 13 scaffolds of 65 contigs, contains 8369 protein-coding genes and 128 RNA-only encoding genes, and is part of the GEBA-RNB project proposal (Project ID 882).

Ensifer medicae WSM244 is an aerobic, motile, Gram-negative, non-spore-forming rod that can exist as a soil saprophyte or as a legume microsymbiont of Medicago species. WSM244 was isolated in 1979 from a nodule recovered from the roots of the annual Medicago polymorpha L. growing in alkaline soil (pH 8.0) in Tel Afer, Iraq. WSM244 is the only acid-sensitive E. medicae strain that has been sequenced to date. It is effective at fixing nitrogen with M. polymorpha L., as well as with more alkaline-adapted Medicago spp. such as M. littoralis Loisel., M. scutellata (L.) Mill., M. tornata (L.) Mill. and M. truncatula Gaertn. This strain is also effective with the perennial M. sativa L. Here we describe the features of E. medicae WSM244, together with genome sequence information and its annotation. The 6,650,282 bp high-quality permanent draft genome is arranged into 91 scaffolds of 91 contigs containing 6,427 protein-coding genes and 68 RNA-only encoding genes, and is one of the rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project proposal.

Genome analysis of fourteen mimosoid and four papilionoid beta-rhizobia together with fourteen reference alpha-rhizobia for both nodulation (nod) and nitrogen-fixing (nif/fix) genes has shown phylogenetic congruence between 16S rRNA/MLSA (combined 16S rRNA gene sequencing and multilocus sequence analysis) and nif/fix genes, indicating a free-living diazotrophic ancestry of the beta-rhizobia. However, deeper genomic analysis revealed a complex symbiosis acquisition history in the beta-rhizobia that clearly separates the mimosoid and papilionoid nodulating groups. Mimosoid-nodulating beta-rhizobia have nod genes tightly clustered in the nodBCIJHASU operon, whereas papilionoid-nodulating Burkholderia have nodUSDABC and nodIJ genes, although their arrangement is not canonical because the nod genes are subdivided by the insertion of nif and other genes. Furthermore, the papilionoid Burkholderia spp. contain duplications of several nod and nif genes. The Burkholderia nifHDKEN and fixABC genes are very closely related to those found in free-living diazotrophs. In contrast, nifA is highly divergent between both groups, but the papilionoid species nifA is more similar to alpha-rhizobia nifA than to other groups. Surprisingly, for all Burkholderia, the fixNOQP and fixGHIS genes required for cbb3 cytochrome oxidase production and assembly are missing. In contrast, symbiotic Cupriavidus strains have fixNOQPGHIS genes, revealing a divergence in the evolution of two distinct electron transport chains required for nitrogen fixation within the beta-rhizobia.

Burkholderia sp. strain UYPR1.413 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Parapiptadenia rigida collected at the Angico plantation, Mandiyu, Uruguay, in December 2006. A survey of symbionts of P. rigida in Uruguay demonstrated that this species is nodulated predominantly by Burkholderia microsymbionts. Moreover, Burkholderia sp. strain UYPR1.413 is a highly efficient nitrogen fixing symbiont with this host. Currently, the only other sequenced isolate to fix with this host is Cupriavidus sp. UYPR2.512. Therefore, Burkholderia sp. strain UYPR1.413 was selected for sequencing on the basis of its environmental and agricultural relevance to issues in global carbon cycling, alternative energy production, and biogeochemical importance, and is part of the GEBA-RNB project. Here we describe the features of Burkholderia sp. strain UYPR1.413, together with sequence and annotation. The 10,373,764 bp high-quality permanent draft genome is arranged in 336 scaffolds of 342 contigs, contains 9759 protein-coding genes and 77 RNA-only encoding genes.

Cupriavidus sp. strain UYPR2.512 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Parapiptadenia rigida grown in soils from a native forest of Uruguay. Here we describe the features of Cupriavidus sp. strain UYPR2.512, together with sequence and annotation. The 7,858,949 bp high-quality permanent draft genome is arranged in 365 scaffolds of 369 contigs, contains 7,411 protein-coding genes and 76 RNA-only encoding genes, and is part of the GEBA-RNB project proposal.

Rhizobium sullae strain WSM1592 is an aerobic, Gram-negative, non-spore-forming rod that was isolated from an effective nitrogen (N2) fixing root nodule formed on the short-lived perennial legume Hedysarum coronarium (also known as Sulla coronaria or Sulla). WSM1592 was isolated from a nodule recovered from H. coronarium roots located in Ottava, bordering Sassari, Sardinia in 1995. WSM1592 is highly effective at fixing nitrogen with H. coronarium, and is currently the commercial Sulla inoculant strain in Australia. Here we describe the features of R. sullae strain WSM1592, together with genome sequence information and its annotation. The 7,530,820 bp high-quality permanent draft genome is arranged into 118 scaffolds of 118 contigs containing 7.453 protein-coding genes and 73 RNA-only encoding genes. This rhizobial genome is sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project.

Strains of a pink-pigmented Methylobacterium sp. are effective nitrogen- (N2) fixing microsymbionts of species of the African crotalarioid genus Listia. Strain WSM2598 is an aerobic, motile, Gram-negative, non-spore-forming rod isolated in 2002 from a Listia bainesii root nodule collected at Estcourt Research Station in South Africa. Here we describe the features of Methylobacterium sp. WSM2598, together with information and annotation of a high-quality draft genome sequence. The 7,669,765 bp draft genome is arranged in 5 scaffolds of 83 contigs, contains 7,236 protein-coding genes and 18 RNA-only encoding genes. This rhizobial genome is one of 100 sequenced as part of the DOE Joint Genome Institute 2010 G enomic E ncyclopedia for B acteria and A rchaea- R oot N odule B acteria (GEBA-RNB) project.

Ensifer medicae Di28 is an aerobic, motile, Gram-negative, non-spore-forming rod that can exist as a soil saprophyte or as a legume microsymbiont of Medicago spp. Di28 was isolated in 1998 from a nodule recovered from the roots of M. polymorpha growing in the south east of Sardinia (Italy). Di28 is an effective microsymbiont of the annual forage legumes M. polymorpha and M. murex and is capable of establishing a partially effective symbiotic association with the perennial M. sativa. Here we describe the features of E. medicae Di28, together with genome sequence information and its annotation. The 6,553,624 bp standard draft genome is arranged into 104 scaffolds of 104 contigs containing 6,394 protein-coding genes and 75 RNA-only encoding genes. This rhizobial genome is one of 100 sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project.

Cupriavidus sp. strain AMP6 is an aerobic, motile, Gram-negative, non-spore-forming rod that was isolated from a root nodule of Mimosa asperata collected in Santa Ana National Wildlife Refuge, Texas, in 2005. Mimosa asperata is the only legume described so far to exclusively associates with Cupriavidus symbionts. Moreover, strain AMP6 represents an early-diverging lineage within the symbiotic Cupriavidus group and has the capacity to develop an effective nitrogen-fixing symbiosis with three other species of Mimosa. Therefore, the genome of Cupriavidus sp. strain AMP6 enables comparative analyses of symbiotic trait evolution in this genus and here we describe the general features, together with sequence and annotation. The 7,579,563 bp high-quality permanent draft genome is arranged in 260 scaffolds of 262 contigs, contains 7,033 protein-coding genes and 97 RNA-only encoding genes, and is part of the GEBA-RNB project proposal.