title: Pseudoxanthomonas taiwanensis sp. nov., a novel thermophilic, N2O-producing species isolated from hot springs.
abstract: Two novel thermophilic bacterial strains, with an optimum growth temperature of between 50 and 60 degrees C, were isolated from the Chi-ban Hot Springs in eastern Taiwan. Strains CB-225 and CB-226(T) were aerobic, thermophilic, non-sporulating, yellow-pigmented heterotrophic organisms. These strains exhibited an unusual denitrification reaction, reducing nitrite, but not nitrate, with the production of N2O only. On the basis of a phylogenetic analysis of 16S rDNA sequences, DNA-DNA similarity data, morphological, physiological and biochemical characteristics, and fatty acid compositions, it was found that the novel strains belonged to the genus Pseudoxanthomonas and represented a novel species within this genus, for which the name Pseudoxanthomonas taiwanensis is proposed; the type strain is CB-226(T) (= ATCC BAA-404(T) = CCRC 17172(T)). P. taiwanensis differs from the only member of the genus Pseudoxanthomonas, the mesophilic species Pseudoxanthomonas broegbernensis, in that it exhibits a higher growth temperature and different morphological characteristics, such as the absence of polar flagella.
authors.affiliation: Department of Botany, National Taiwan University, 106 Taipei, Taiwan.
authors.forename: Mao-Yen
authors.initials: MY
authors.lastname: Chen
authors.forename: San-San
authors.initials: SS
authors.lastname: Tsay
authors.forename: Kuei-Yu
authors.initials: KY
authors.lastname: Chen
authors.forename: Yu-Ching
authors.initials: YC
authors.lastname: Shi
authors.forename: Yung-Ting
authors.initials: YT
authors.lastname: Lin
authors.forename: Guang-Huey
authors.initials: GH
authors.lastname: Lin
mesh_terms: D001482:Base Composition; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D005227:Fatty Acids / Q000032:analysis; D005618:Fresh Water / Q000382:microbiology; D020563:Gammaproteobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D005798:Genes, Bacterial; D006358:Hot Temperature; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009609:Nitrous Oxide / Q000378:metabolism; D010641:Phenotype; D010802:Phylogeny; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013624:Taiwan; D009626:Terminology as Topic; D014974:Xanthomonas / Q000145:classification / Q000235:genetics / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D005227:Fatty Acids; D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S; D009609:Nitrous Oxide