A recently isolated, selenate-respiring microorganism (strain AXT [T = type strain]) was classified by using a polyphasic approach in which both genotypic and phenotypic characteristics were determined. Strain AXT is a motile, gram-negative, rod-shaped organism with a singlepolar flagellum. On the basis of phenotypic characteristics, this organism can be classified as a Pseudomonas sp. However, a comparison of the 16S rRNA sequence of strain AXT with the sequences of other organisms indicated that strain AXT is most similar to members of the beta subclass (level of similarity, 86.8%) rather than to members of the gamma subclass (level of similarity, 80.2%) of the Proteobacteria. The presence of the specific polyamine 2-hydroxyputrescine and the presence of a ubiquinone with eight isoprenoid units in the side chain (ubiquinone Q-8) excluded strain AXT from the authentic genus Pseudomonas and allowed placement in the beta subclass of the Proteobacteria. Within the beta subclass, strain AXT is related to Iodobacter fluvatile. The phylogenetic distance (level of similarity, less than 90%), as well as a lack of common phenotypic characteristics between these organisms, prevents classification of strain AXT as a member of the genus Iodobacter. In addition, strain AXT possesses a unique mechanism for anaerobic respiration, which allows it to utilize selenate as an electron acceptor without interference by nitrate. Therefore, we propose that strain AXT should be the first member of a new genus and species, Thauera selenatis.
AulingG.,
BusseH.-J.,
PilzF.,
WebbL.,
KneifeiH.,
ClausD.1991; Rapid differentiation by polyamine analysis of Xanthomonas from phytopathogenic pseudomonads and other members of Proteobacteria interacting with plants. Int. J. Syst. Bacteriol. 41:223–228
BeckingJ. H.1984; Genus Dencia Jensen, De and Bhattacharya 1969. 321–325 In
KriegN. R.,
HoltJ. G.
(ed.) Bergey’s manual of systematic bacteriology vol 1 Williams Wilkins Co; Baltimore:
BowmanJ. P.,
SlyL. I.,
HaywardA. C.1988; Pseudomonas mixta sp. nov., a bacterium from soil with degradative activity on a variety of complex polysaccharides. Syst. Appl. Microbiol 11:53–59 Wilkins Co; Baltimore:
BowmanJ. P.,
StackebrandtE.,
SlyL. I.
Unpublished data
BusseH.-J.
1990; Chemotaxonomische und phylogenetische Charakterisierung von Schadstoffe abbauenden Gram-negativen Mikroorganismen. Ph.D. thesis University of Hannover, Hannover; Germany:
BusseH.-J.,
AulingG.1992; The genera Alcaligenes and “Achromobacter”. p. 2542–2555 In
BalowsA.,
TrperH.-G.,
DworkinM.,
HarderW.,
SchleiferK.-H.
(ed.) The prokaryotes. A handbook on the biology of bacteria: ecophysiology, isolation, identification, applications, 2nd ed. Springer-Verlag; New York:
BusseH.-J.,
EI-BannaT.,
AulingG.1989; Evaluation of different approaches for identification of xenobiotic-degrading pseudomonads. Appl. Environ. Microbiol 55:1578–1583
BusseH.-J.,
El-BannaT.,
OyaizuH.,
AulingG.1992; Identification of xenobiotic-degrading isolates from the beta subclass of the Proteobacteria by a polyphasic approach including 16S rRNA partial sequencing. Int. J. Syst. Bacteriol 42:19–16
De VosP.,
De LeyJ.1983; Intra- and intergeneric similarities of Pseudomonas and Xanthomonas ribosomal ribonucleic acid cistrons. Int. J. Syst. Bacteriol 33:487–509
De VosP.,
GoorM.,
GillisM.,
De LeyJ.1985; Ribosomal ribonucleic acid cistron similarities of phytopathogenic Pseudomonas species. Int. J. Syst. Bacteriol 35:169–184
De VosP.,
KerstersK.,
FalsenE.,
PotB.,
GillisM.,
SegersP.,
De LeyJ.1985; Comamonas Davis and Park 1962 gen. nov. rev. emend., and Comamonas terrigena Hugh 1962 sp. nom. rev. Int. J. Syst. Bacteriol 35:443–453
De VosP.,
Van LandschootA.,
SegersP.,
TytgatR.,
GillisM.,
BauwensM.,
RossauR.,
GoorM.,
PotB.,
KerstersK.,
LizzaragP.,
De LeyJ.1989; Genotypic relationships and taxonomic localization of unclassified Pseudomonas and Pseudomonas- like strains by deoxyribonucleic acid-ribosomal ribonucleic acid hybridizations. Int. J. Syst. Bacteriol 39:35–49
DewhirstF. E.,
PasterB. J.,
BrightP. L.1989; Chromobacterium, Eikenella, Kingella, Neisseria, Simonsiella, and Vitreoscilla species comprise a major branch of the beta group Proteobacteria by 16S ribosomal ribonucleic acid sequence comparison: transfer of Eikenella and Simonsiella to the family Neisseriaceae (emend.). Int. J. Syst. Bacteriol 39:258–266
GhernaR.,
PientaP.,
CoteR.
(ed.) 1989; American Type Culture Collection Catalogue of Bacteria and Phages. , 17th ed. American Type Culture Collection; Rockville, Md:
GlauertA.1975; Practical methods in electron microscopy, fixation, dehydration and embedding of biological specimens. American Elsevier Publishing Co; New York:
JennemanG. E.,
MontgomeryA.,
MclnemeyM. J.1986; Method for detection of microorganisms that produce gaseous nitrogen oxides. Appl. Environ. Microbiol 51:776–780
KerstensK.,
De LeyJ.1984; Genus Alcaligenes Castellani and Chalmers 1919. p. 361–373 In
KriegN. R.,
HoltJ. G.
(ed.) Bergey’s manual of systematic bacteriology vol 1 The Williams & Wilkins Co; Baltimore:
KriegN. R.1984; Genus Aquaspirillum Hylemon, Wells, Krieg and Jannasch 1973. p. 72–90 In
KriegN. R.,
HoltJ. G.
(ed.) Bergey’s manual of systematic bacteriology vol. 1 The Williams & Wilkins Co; Baltimore:
LoganN. A.1989; Numerical taxonomy of violet-pigmented, gram-negative bacteria and description of Iodobacter fluviatile gen. nov. comb. nov. Int. J. Syst. Bacteriol 39:450–156
MacyJ. M.,
MichelT. A.,
KirschD. G.1989; Selenate reduction by a Pseudomonas species: a new mode of anaerobic respiration. FEMS Microbiol. Lett 61:195–198
NelsonD. C.,
WaterburyJ. B.,
JannaschH. W.1984; DNA base composition and genome size of the prokaryotic symbiont in Riftia pachyptila (Pogonophora). FEMS Microbiol. Lett 24:267–271
O’ConnorS. P.,
DorschM.,
SteigerwaltA. G.,
BrennerD. J.,
StackebrandtE.1991; 16S rRNA sequences of Bartonella bacilliformis and cat scratch disease bacillus reveal phylogenetic relationships with the alpha-2 subgroup of the class Proteobacteria.. J. Clin. Microbiol 29:2144–2150
OyaizuH.,
KomagataK.1983; Grouping of Pseudomonas species on the basis of cellular fatty acid composition and the quinone system with special reference to the existence of 3-hydroxy fatty acids. J. Gen. Appl. Microbiol 29:17–40
PalleroniN. J.1984; Genus I. Pseudomonas Migula 1894. p. 141–219 In
KriegN. R.,
HoltJ. G.
(ed.) Bergey’s manual of systematic bacteriology vol. 1 The Williams & Wilkins Co.; Baltimore:
RaineyF.,
DorschM.,
MorganH. W.,
StackebrandtE.1992; 16S rDNA analysis of Spirochaeta thermophila its phylogenetic position and implications for the systematics of the order Spirochaetales.. Syst. Appl. Microbiol 15:197–202
SmibertR. M.,
KriegN. R.1981; General characterization. p. 411–449InGerhardtP.,
MurrayR. G. E.,
CostilowR. N.,
NesterE. W.,
WoodW. A.,
KriegN. R.,
PhillipsG. B.
(ed.) Manual of methods for general microbiology American Society for Microbiology; Washington D.C:
SneathP. H. A.1984; Genus Janthinobacterium De Ley, Segers and Gillis 1974. p. 376–377 In
KriegN. R.,
HoltJ. G.
(ed.) Bergey’s manual of systematic bacteriology vol 1 The Williams & Wilkins Co; Baltimore:
SneathP. H. A.1984; Genus Chromobacterium Bergonzini 1881. p. 580–582 In
KriegN. R.,
HoltJ. G.
(ed.) Bergey’s manual of systematic bacteriology vol 1 The Williams & Wilkins Co; Baltimore:
StackebrandtE.,
MurrayR. G. E.,
TriiperH. G.1988.; Proteobacteria classis nov., name for the phylogenetic taxon that includes the “purple bacteria and their relatives”. Int. J. Syst. Bacteriol 38:321–325
SwingsJ.,
De VosP.,
Van Den MooterM.,
De LeyJ.1983; Transfer of Pseudomonas maltophilia Hugh 1981 to the genus Xanthomonas as Xanthomonas maltophilia (Hugh 1981) comb, nov. Int. J. Syst. Bacteriol 33:409–413
WillemsA.,
De LeyJ.,
GillisM.,
KerstersK.1991; Comamonadaceae, a new family encompassing the acidovorans rRNA complex, including Variovorax paradoxus gen. nov., comb, nov., for Alcaligenes paradoxus (Davis 1969). Int. J. Syst. Bacteriol 41:445–450
WillemsA.,
FalsenE.,
PotB.,
JantzenE.,
HosteB.,
Van- dammeP.,
GillisM.,
KerstersK.,
De LeyJ.1990; Acidovorax, a new genus for Pseudomonas facilis, Pseudomonas delafieldii, EF group 13, EF group 16, and several clinical isolates, with the species Acidovorax facilis comb, nov., Acidovorax delafieldii comb, nov., and Acidovorax temperans sp. nov. Int. J. Syst. Bacteriol 40:384–398
WillemsA.,
GillisM.,
KerstersK.,
Van den BroeckeL.,
De LeyJ.1987; Transfer of Xanthomonas ampelina Panagopoulos 1969 to a new genus, Xylophilus gen. nov., and Xylophilus ampelinu (Panagopoulos 1969) comb. nov. Int. J. Syst. Bacterid 37:422–430
WillemsA.,
PotB.,
FalsenE.,
VandammeP.,
GillisM.,
KerstersK.,
De LeyJ.1991; Polyphasic taxonomic study of the emended genus Comamonas: relationship to Aquaspirillum aquaticum, E. Falsen group 10, and other clinical isolates. Int. J. Syst. Bacteriol 41:427–444
WoeseC. R.,
BlanzP.,
HahnC. M.1984; What isn’t a pseudomonad: the importance of nomenclature in bacterial classification. Syst. Appl. Microbiol 5:179–195
WoeseC. R.,
WeisburgW. G.,
PasterB. J.,
HahnC. M.,
TannerR. S.,
KriegN. R.,
KoopsH.-P.,
HarmsH.,
Stacke- brandtE.1984; The phylogeny of purple bacteria: the beta subdivision. Syst. Appl. Microbiol 5:327–336
YabuuchiE.,
YanoI.,
OyaizuH.,
HashimotoY.,
EzakiT.,
YamamotoH.1990; Proposals of Sphingomonas paucimobilis gen. nov. and comb, nov., Sphingomonasparapaucimobilis sp. nov., Sphingomonas yanoikuyae sp. nov., Sphingomonas ad haesiva sp. nov., Sphingomonas capsulata comb, nov., and two genospecies of the genus Sphingomonas. Microbiol. Immunol 34:99–119