Polyphasic Taxonomy in the Genus Burkholderia Leading to an Emended Description of the Genus and Proposition of Burkholderia vietnamiensis sp. nov. for N2-Fixing Isolates from Rice in Vietnam

Abstract

F-54501 Vandewre-les-Nancy, and URA CNRS 1977, Ecologie Microbienne, USBSE,The taxonomic position of nitrogen-fixing strains that were isolated from rhizosphere macerates of rice cultivated in the Binh Thanh region of Vietnam was determined by using polyphasic taxonomy. We determined the phylogenetic relationships of these organisms by performing DNA-rRNA hybridization experiments with a labeled rRNA probe from the type strain of Burkholderia cepacia, and we found that they belong to a single rRNA complex. Other members of this rRNA complex were also studied, and the N,-fixing strains were found to be closely related to B. cepacia. In addition, all members of the rRNA complex containing B. cepacia were studied by performing auxanographic and DNA-DNA hybridization experiments. Phenotypically and genotypically, the N,-fixing isolates constitute a single cluster together with two strains of clinical origin. These organisms constitute a new Burkholderia species, for which the name Burkholderia vietnamiensis is proposed; the type strain of this species is TVV75 (= LMG 10929). All members of this species can fix nitrogen. On the basis of our polyphasic taxonomy results and previously published data we concluded that the genus Burkholderia should be restricted to the following species: B. cepacia (the type species), Burkholderia mallei, Burkholderia pseudomallei, B. vietnamiensis, Burkholderia gladioli, Burkholderia caryophylli, Burkholderia plantarii, Burkholderia glumue, Burkholderia vandii, BurkhoMeria cocovenenans comb. nov., and Burkholderia andropogonis comb. nov. On the basis of genotypic and phenotypic results [Alcaligenes] eutrophus, [BurkhoZderia] solanacearum, and[Burkholderia] pickettii belong to two other clusters whose internal structures must be studied further.On the basis of the results of extensive phenotypic studies and DNA-rRNA and DNA-DNA hybridization experiments performed by Palleroni, Stanier, and their collaborators, the genus Pseudomonas was divided into five groups (24, 43, 46, 56). Additional phylogenetic data have shown that these groups are only very remotely related and that each of them contains species belonging to other genera (21-23, 70, 71). In addition to the former pseudomonads that have been shown to belong to the genus Xanthomonas and to a smaller group related to Pseudomonas diminuta and Pseudomonas vesicularis (21-23,43) classified in the recently described genus Brevundirnonas (52), three large groups of pseudomonads can be considered. Pseudomonas rRNA group I (43) is part of rRNA superfamily I1 (18) or the gamma subclass of the Proteobacteria (S), where it constitutes a separate rRNA complex (18,21,22,68); this group represents the authentic pseudomonads which are grouped with Pseudomonas aeruginosa, the type species (43). Although the internal relationships within this group have not been determined yet, it is evident that the genus Pseudomonas must be limited to this group and that all other Pseudomonas species have been generically misnamed as determined by phylogenetic da...

Burkholderia unamae sp. nov., an N2-fixing rhizospheric and endophytic species

“…For a long time, N 2 -fixing ability in bacteria of the genus Burkholderia was recognized only in the species Burkholderia vietnamiensis (Gillis et al, 1995). Recently, analysis of maize, sorghum and coffee plants grown under field conditions revealed the richness of the genus Burkholderia in unknown diazotrophs and the N 2 -fixing ability of B. kururiensis (Estrada-de los Santos et al, 2001).…”

Burkholderia zhejiangensis sp. nov., a methyl-parathion-degrading bacterium isolated from a wastewater-treatment system

“…Other fatty acids detected (that each exceeded 1 % of the total fatty acid content) were summed feature 3 (consisting of C 16 : 1 v7c and/or C 16 : 1 v6c; 7.20 %), C 16 : 0 2-OH (5.66 %), C 14 : 0 (5.49 %), summed feature 2 (consisting of C 14 : 0 3-OH and/or iso-C 16 : 1 I; 5.39 %), C 16 : 0 3-OH (4.73 %), C 19 : 0 v8c cyclo (4.38 %) and C 16 : 1 2-OH (1.03 %). The major cellular fatty acids and the presence of C 16 : 0 3-OH are characteristic of members of the genus Burkholderia (Gillis et al, 1995). The detailed fatty acid profiles of strain OP-1 T and closely related species of the genus Burkholderia are shown in Table S1 (available in IJSEM Online).…”

Atividade antimicrobiana de fungos endofíticos isolados de plantas tóxicas da amazônia: Palicourea longiflora (aubl.) rich e Strychnos cogens bentham

“…As linhagens foram identificadas como Burkholderia gladioli, pertencentes a um grupo de fixadoras de nitrogênio. "Em solos muito pobres como o da Amazônia, a presença de bactérias endofíticas fixadoras de nitrogênio ajuda a entender tamanha exuberância e riqueza da flora e, consequentemente, da fauna" (Pavan e Moreira-Filho, 1998 O grupo Burkholderia é composto por várias espécies que tem sido isoladas da rizosfera de diversos vegetais, de pacientes com fibrose cística (Whitby et al, 2000) e recentemente, de algumas plantas tropicais como cana-deaçúcar, gramíneas (Baldani, 1996), arroz (Gillis et al, 1995), mandioca (Belota, 1994) e abacaxi (Weber et al, 2000). Coenye et al (2000) fizeram a comparação das sequências da região 16S rDNA de Pseudomonas antimicrobica e constataram que ela pertencia ao grupo Burkholderia.…”