The taxonomic status of four strains from several mineral water sources in Taejon, Korea, was examined. The DNA base compositions of these strains ranged from 62 to 66 mol %. All of the strains contained sphingolipids and ubiquinone 10 as the main respiratory quinone. The cellular fatty acids of these strains included octadecenoic acid, hexadecanoic acid and 2-hydroxymyristic acid, without 3-hydroxy fatty acids. On the basis of morphological, physiological and chemotaxonomic characteristics, together with 16S rDNA sequence comparison and DNA-DNA reassociation data, three new species of the genus Sphingomonas are proposed for the strains isolated from natural mineral water: Sphingomonas aquatilis sp. nov. for strain JSS7T (= KCTC 2881T = KCCM 41067T), Sphingomonas koreensis sp. nov. for strains JSS26T (= KCTC 2882T = KCCM 41069T) and JSS28 (= KCTC 2883 = KCCM 41066) and Sphingomonas taejonensis sp. nov. for strain JSS54T (= KCTC 2884T = KCCM 41068T).

Proposal of the genus Thermoactinomyces sensu stricto and three new genera, Laceyella, Thermoflavimicrobium and Seinonella, on the basis of phenotypic, phylogenetic and chemotaxonomic analyses Phylogenetic analysis based on 16S rRNA gene sequences revealed that Thermoactinomyces species with validly published names can be assigned to four clusters or lineages. The type strains of Thermoactinomyces sacchari and Thermoactinomyces putidus were differentiated from the type strains of Thermoactinomyces vulgaris and Thermoactinomyces intermedius by the predominant menaquinone and fatty acid profiles. The type strains of Thermoactinomyces dichotomicus and Thermoactinomyces peptonophilus formed lines of descent distinct from other Thermoactinomyces species. Thermoactinomyces dichotomicus KCTC 3667 T was distinguishable from the type strains of Thermoactinomyces vulgaris and Thermoactinomyces intermedius by the contents of two fatty acids, iso-C 16 : 0 and iso-C 17 : 0 . Thermoactinomyces dichotomicus could be distinguished from other Thermoactinomyces species by DNA G+C content and some phenotypic properties, particularly its property of forming a yellow colour. The type strain of Thermoactinomyces peptonophilus was distinguishable from other Thermoactinomyces species by differences in menaquinone profile, major fatty acids, DNA G+C content and some physiological properties including optimal growth temperature. On the basis of these data, the creation of three new genera, Laceyella, Thermoflavimicrobium and Seinonella, is proposed in addition to the genus Thermoactinomyces sensu stricto. The genus Laceyella gen. nov. is proposed to accommodate Thermoactinomyces sacchari and Thermoactinomyces putidus as Laceyella sacchari comb. nov. and Laceyella putida comb. nov., the genus Thermoflavimicrobium gen. nov. is proposed for Thermoactinomyces dichotomicus as Thermoflavimicrobium dichotomicum comb. nov. and the genus Seinonella gen. nov. is proposed for Thermoactinomyces peptonophilus as Seinonella peptonophila comb. nov.The genus Thermoactinomyces was proposed by Tsilinsky (1899) with the single species Thermoactinomyces vulgaris. Additional Thermoactinomyces species have since been described: Thermoactinomyces sacchari (Lacey, 1971), Thermoactinomyces peptonophilus (Nonomura & Ohara, 1971), Thermoactinomyces candidus (Kurup et al., 1975), Thermoactinomyces intermedius (Kurup et al., 1980), Thermoactinomyces thalpophilus (Unsworth & Cross, 1980) and Thermoactinomyces putidus (Lacey & Cross, 1989).Thermoactinomyces dichotomicus was proposed for 'Actinobifida dichotomica', described previously by Krasil'nikov & Agre (1964) (Cross & Goodfellow, 1973). More recently, Thermoactinomyces candidus was reclassified as a synonym of Thermoactinomyces vulgaris and Thermoactinomyces thalpophilus as a synonym of Thermoactinomyces sacchari . Thermoactinomyces species were long recognized as actinomycetes because of their morphological characteristics, forming aerial and substrate mycelia. On the basis of endospore formation, DNA G+C conten...

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The taxonomic position of a misclassified strain, Zoogloea ramigera IAM 12670T (= ATCC 25925T = P. R. Dugan lUT), was reevaluated. A phylogenetic analysis based on 16s ribosomal rDNA sequences revealed that this organism was located in the beta subclass of the class Proteobacteria with members of the genus TeZZuria as its closest relatives. On the basis of phenotypic and phylogenetic information, we propose that this organism should be reclassified in a new taxon with the name Duganella zoogloeoides gen. nov., sp. nov.

Three strains of " Agrobacterium sanguineum", an aerobic marine bacterial species described previously, were re-characterized from phylogenetic and taxonomic viewpoints. 16S rDNA sequence comparisons showed that the " A. sanguineum" strains belong to the alpha-4 subgroup of alpha-Proteobacteria, with members of the genera Erythromicrobium and Porphyrobacter as their closest relatives. DNA-DNA hybridization studies indicated that the " A. sanguineum" strains were distinguishable from any previously known species of these genera. Bacteriochlorophyll a, monosaccharide-type glycosphingolipids, 2-OH fatty acids of C14:0, C15:0, C16:0, and C16:1, and ubiquinone-10 were detected in the " A. sanguineum" strains. The G+C of the DNA was 63.8-64.0 mol%. Two of the " A. sanguineum" strains, IAM 12620 (=ATCC 25659) and ATCC 25661, were able to grow with biphenyl and dibenzofuran as sole carbon source in the presence of 0.05% yeast extract. The medium in these cultures turned yellowish-orange at the exponential phase of growth due to the release of soluble chromogenic metabolites. The remaining " A. sanguineum" strain, ATCC 25660, and all test strains of Erythromicrobium and Porphyrobacter neither grew nor produced yellow-orange pigment with biphenyl or dibenzofuran. In PCR experiments, bphA1 gene, coding for the large subunit protein of biphenyl dioxygenase, was detected in " A. sanguineum" IAM 12620 and ATCC 25661. Based on these results, we propose classifying " A. sanguineum" IAM 12620 and ATCC 25661 as a new species of the genus Porphyrobacter with the name Porphyrobacter sanguineus sp. nov.