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Two bacterial strains, isolates AC10T and AC20, which were reported in a previous study on the diversity of acetic acid bacteria in Thailand, were subjected to a taxonomic study. The phylogenetic analysis based on the 16S rRNA gene sequences showed that the two isolates were located closely to the type strains of Gluconobacter oxydans and Gluconobacter roseus . However, the two isolates formed a separate cluster from the type strains of the two species. The genomic DNA of isolate AC10T was sequenced. The assembled genomes of the isolate were analysed for average nucleotide identity (ANI) and digital DNA–DNA hybridization (dDDH). The results showed that the highest ANI and dDDH values between isolate AC10T and G. oxydans DSM 3503T were 91.15 and 68.2 %, which are lower than the suggested values for species delineation. The genome-based tree was reconstructed and the phylogenetic lineage based on genome sequences showed that the lineage of isolate AC10T was distinct from G. oxydans DSM 3503T and its related species. The two isolates were distinguished from G. oxydans and their relatives by their phenotypic characteristics and MALDI-TOF profiles. Therefore, the two isolates, AC10T (=BCC 15749T=TBRC 11329T=NBRC 103576T) and AC20 (=BCC 15759=TBRC 11330=NBRC 103579), can be assigned to an independent species within the genus Gluconobacter , and the name Gluconobacter aidae sp. nov. is proposed for the two isolates.

Two bacterial strains, designated as isolates VTH-Ai14T and VTH-Ai15, that have plant growth-promoting ability were isolated during the study on acetic acid bacteria diversity in Vietnam. The phylogenetic analysis based on 16S rRNA gene sequences showed that the two isolates were located closely to Acetobacter nitrogenifigens RG1T but formed an independent cluster. The phylogenetic analysis based on 16S rRNA gene and three housekeeping genes’ (dnaK, groEL, and rpoB) sequences were analyzed. The genomic DNA of the two isolates, VTH-Ai14T and VTH-Ai15, Acetobacter nitrogenifigens RG1T, the closest phylogenetic species, and Acetobacter aceti NBRC 14818T were hybridized and calculated the %similarity. Then, phenotypic and chemotaxonomic characteristics were determined for species’ description using the conventional method. The 16S rRNA gene and concatenated of the three housekeeping genes phylogenetic analysis suggests that the two isolates were constituted in a species separated from Acetobacter nitrogenifigens, Acetobacter aceti, and Acetobacter sicerae. The two isolates VTH-Ai14T and VTH-Ai15 showed 99.65% and 98.65% similarity of 16S rRNA gene when compared with Acetobacter nitrogenifigens and Acetobacter aceti and they were so different from Acetobacter nitrogenifigens RG1T with 56.99 ± 3.6 and 68.15 ± 1.8% in DNA-DNA hybridization, when isolates VTH-Ai14T and VTH-Ai15 were respectively labeled. Moreover, the two isolates were phenotypically distinguished from Acetobacter nitrogenifigens in growth in the presence of 0.35% acetic acid (v/v), on nitrogen-free LGI medium and D-mannitol, and in no ability to solubilize phosphate. Therefore, the two isolates, VTH-Ai14T(= VTCC 910031T= BCC 67843T= TBRC 11175T= NRIC 0977T) and VTH-Ai15 (= VTCC 910032 = BCC 67844 = TBRC 11176 = NRIC 0978), can be assigned to an independent species within the genus Acetobacter, and the name of Acetobacter sacchari sp. nov. is proposed for the two isolates.

Two Gram-staining-negative, strictly aerobic, rod-shaped bacteria, designated strains AVA-1T and AVA-2, were isolated from the root of Aloe vera (L.) Brum.f. derived from Chachoengsao Province, Thailand. The strains contained cytochrome oxidase and catalase activities. They grew in 4 % (w/v) NaCl, at a pH range of 6.0–9.0 (optimally at pH 7) and at 20–42 °C (optimally at 30–37 °C). The major isoprenoid quinone was ubiquinone with eight isoprene units (Q-8). The major fatty acids were C16 : 0 and C17 : 0 cyclo. On the basis of 16S rRNA gene sequence analysis, the strains represent a species belonging to the genus Achromobacter and are closely related to Achromobacter xylosoxidans NBRC 15126T (98.80 %), Achromobacter insolitus LMG 6003T (98.64 %), Achromobacter aminicus LMG 26690T (98.59 %), Achromobacter pulmonis LMG 26696T (98.58 %) and Achromobacter insuavis LMG 26845T (98.58 %). The DNA G+C content of strain AVA-1T was 66.5 mol%. The novel strains had low DNA–DNA relatedness values with related type strains. On the basis of the phenotypic and genotypic data obtained, the strains clearly represent a novel species, for which the name Achromobacter aloeverae sp. nov. is proposed. The type strain is strain AVA-1T (=LMG 29108T=NBRC 111463T=PCU 352T=TISTR 2383T).

A Gram-negative, rod-shaped, and non-motile bacterium, designated as AI32T, was isolated from a fruit in Surat Thani, the southern district of Thailand. Phylogenetic analyses of the 16S rRNA gene, 16S-23S rRNA gene ITS, and groEL gene sequences showed that the isolate formed a quite independent cluster located outside the clusters of Acetobacter peroxydans and Acetobacter papayae. Analysis of 16S rRNA gene sequence showed that the isolate was related to the type strains of A. peroxydans and A. papayae, respectively, with 99.4 % and 99.3 % similarities. The DNA G + C content of the isolate was 59.6 mol%. The isolate was positive in catalase test and showed no growth on ethanol in the presence of ammonium sulfate. The isolate produced only d-gluconic acid from d-glucose. The predominant fatty acid of isolate AI32T was C18:1ω7C. Based on the results obtained in physiological and biochemical tests and in genotypic differences between the isolate and the type strains of the validly named species of the genus Acetobacter, the isolate is classified as a novel species, for which the name of Acetobacter suratthanensis sp. nov. is introduced. The type strain of the species is AI32T (= BCC 26087T = NBRC 111399T).

Tanticharoenia aidae sp. nov. was introduced for two strains, designated as VTH-Ai06T and VTH-Ai07, which were isolated from the stems of sugar cane collected in Vietnam. In a phylogenetic tree based on 16S rRNA gene sequences derived from the neighbor-joining method, the two strains formed a cluster along with the type strain of Tanticharoenia sakaeratensis with a bootstrap value of 64 %. The pair-wise 16S rRNA gene sequence similarity was 98.3 % between strain VTH-Ai06T and the type strain of T. sakaeratensis. The range of DNA G+C contents was from 65.2 to 65.4 mol%. In DNA–DNA hybridization, the two strains showed low similarities to T. sakaeratensis BCC 15772T. Cellular fatty acids were of C18:1ω7c as a major. A major isoprenoid quinone was Q-10. Phenotypically, the two strains differed from the type strain of T. sakaeratensis in no production of dihydroxyacetone from glycerol. The type strain is VTH-Ai06T (= VTCC 910001T = BCC 67839T = NBRC 110637T), whose DNA G+C content was 65.4 mol%.

Flexibacter tractuosa [Lewin, 1969] was reclassified as Marivirga tractuosa . Flexibacter tractuosus NBRC 15981T was reclassified herein by using a polyphasic taxonomic approach. Cells of the strain were strictly aerobic, Gram-stain-negative, slender rods, which were motile by gliding. The major respiratory quinone was menaquinone-7 and the predominant (>5 %) cellular fatty acids were iso-C15 : 0, iso-G-C15 : 1, C16 : 1ω7c and iso-C17 : 0 3-OH. The polar lipid pattern indicated the presence of a phosphatidylethanolamine, several unidentified aminolipids, glycolipids and five unidentified polar lipids. The G+C content of the genomic DNA was 35.8 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain NBRC 15981T clustered with members of the genus Marivirga in the family Flammeovirgaceae of the phylum Bacteroidetes . Levels of DNA–DNA relatedness were less than 16 % between strain NBRC 15981T and the two closely related species, Marivirga sericea NBRC 15983T and Marivirga tractuosa NBRC 15989T. Strain NBRC 15981T could be differentiated from these type strains in the genus Marivirga based on the polar lipid pattern and the activity of α-chymotrypsin, as well as by α-glucosidase and β-glucosidase activity. On the basis of these results, NBRC 15981T is proposed as representing a novel species of the genus Marivirga , named Marivirga harenae sp. nov. The type strain is JK11T (=NBRC 15981T=NCIMB 1429T).

A coccoid and amorphous-shaped, non-gliding, proteorhodopsin-containing, yellow bacterium, designated strain SG-18T, was isolated from seawater in the western North Pacific Ocean near Japan. The strain was Gram-stain-negative, obligately aerobic, heterotrophic and oxidase-positive. It hydrolysed aesculin but not DNA, urea, gelatin or agar. Growth occurred in the presence of 1–5 % NaCl, with optimum growth at 2 % NaCl. The strain grew at 15–37 °C with an optimum temperature of 25–30 °C. The DNA G+C content of the genomic DNA of strain SG-18Twas 47.0 mol% (HPLC). The predominant isoprenoid quinone was MK-6, and major cellular fatty acids were iso-C15 : 1G, iso-C15 : 0, iso-C15 : 03-OH. Phylogenetic trees generated by using 16S rRNA gene sequences revealed that strain SG-18Tbelonged to the familyFlavobacteriaceaeand showed 92.7 % sequence similarity to the most closely related species,Croceitalea eckloniaeDOKDO 025T. On the basis of phenotypic and phylogenetic features, strain SG-18Tis classified as representing a novel species of a new genus within the familyFlavobacteriaceae, for which the nameAureicoccus marinusgen. nov., sp. nov. is proposed. The type strain of the type species is SG-18T( = NBRC 108814T = KCTC 23967T).

seven species are now-adays accommodated (Franke et al., 1999; Fuentes-Ramirez et al., 2001; Gillis et al., 1989; Tazato et al., 2012; Yamada and Yukphan, 2008). In the systematic and ecological studies of acetic acid bacteria, the present authors found that a certain strain isolated from the natural environment of Vietnam was located in a unique phylogenetic position, name-ly, outside of the

Two aerobic, Gram-negative, orange pigmented and irregular rod-shaped bacteria, designated S1-05 and S1-08T, were isolated from seawater from the Pacific Ocean. Phylogenetic analysis based on their 16S rRNA gene sequences revealed that the novel isolates could be affiliated with the genus Nonlabens of the family Flavobacteriaceae. The strains S1-05 and S1-08T shared 100 % pairwise sequences similarity with each other and showed less than 96.8 % similarity with the cultivated members of the genus Nonlabens. The novel isolates are phenotypically and physiologically different from strains described previously. The strains were found to be non-motile, oxidase positive, catalase positive and hydrolyzed gelatin and aesculin. The G+C contents of the DNA were determined to 41.4 and 41.7 mol% and MK-6 the predominant menaquinone. Anteiso-C15:0 and iso-C15:0 were found to be the major two cellular fatty acids. On the basis of polyphasic taxonomic studies, it was concluded that strains S1-05 and S1-08T represent a novel species within the genus Nonlabens, for which the name Nonlabens marina sp. nov. is proposed. The type strain of N. marina is S1-08T (=KCTC 23432T = NBRC 107738T).

The ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to discriminate laboratory-derived antibiotic-resistant bacterial strains of known genetic origin was examined. A computer-based cluster analysis of spectral data successfully discriminated the majority of single- as well as multiple-antibiotic-resistant Escherichia coli strains examined. Cluster analysis of Staphylococcus aureus strains with different levels of novobiocin resistance showed that as the degree of resistance increased similarity to the wild-type strain decreased. These results demonstrate that MALDI-TOF MS is capable of discriminating antibiotic-resistant bacterial strains and may have potential for differentiating bacterial strains with varying degrees of antibiotic-resistance.

BACKGROUND: Fermented rice flour (khao-khab, a non-glutinous rice) and related products are Thai traditional products. The types of acetic acid bacteria (AAB) microflora in khao-khab have not been reported. In this study, Acetobacter strains were isolated and identified based on the phenotypic and chemotaxonomic characteristics and molecular aspects. RESULTS: Twenty-five acetic acid bacteria isolated from fermented rice products and a starter for sweetened rice in Thailand by an enrichment culture approach, were assigned to the genus Acetobacter by phenotypic and chemotaxonomic characterisations. On the basis of the 16S rRNA gene sequence and 16S–23S rRNA gene ITS restriction analyses, 25 isolates were divided into six groups and identified at the specific level: (1) Group 1 included five isolates, which were identified as A. indonesiensis; (2) Group 2 included two isolates, which were identified as A. lovaniensis; (3) Group 3 included one isolate, which was identified as A. orientalis; (4) Group 4 included eleven isolates, which were identified as A. pasteurianus; (5) Group 5 included three isolates, which were identified as A. syzygii and (6) Group 6 included three isolates, which were unidentified and considered to constitute a new species. CONCLUSION: Results revealed that various Acetobacter species were distributed in Thai fermented rice flour and related products. A novel Acetobacter species was isolated from the product. Copyright © 2011 Society of Chemical Industry

The genus Gluconacetobacter is divided into two groups phylogenetically, phenotypically and ecologically: the Gluconacetobacter liquefaciens group and the Gluconacetobacter xylinus group. For the latter group, the genus Komagatabacter is newly introduced, and the type species of the new genus is designated as Komagatabacter xylinus (Brown 1886) comb. nov. Twelve species of the Gluconacetobacter xylinus group are transferred to the new genus as new combinations.

A novel bacterium, designated strain OX-01T, was isolated from acidic soil, taxonomically investigated and identified as an agent that catabolizes (+)-catechin into taxifolin. Strain OX-01T is a Gram-reaction-negative, aerobic, non-sporulating, non-motile and rod-shaped bacterium. 16S rRNA gene sequence analysis identified this strain as a member of the genus Burkholderia and occupying a phylogenetic position closest to, but clearly distinct from, Burkholderia sacchari. Strain OX-01T does not have any nif genes, which are required for N2-fixation, in its genome, a feature that is similar to B. sacchari, which lacks nifH, but is distinct from the N2-fixing features of many other phylogenetically related taxa, such as Burkholderia ferrariae, B. heleia, B. mimosarum, B. nodosa, B. silvatlantica, B. tropica and B. unamae. Strain OX-01T has the following chemotaxonomic characteristics: the major ubiquinone is Q-8, the DNA G+C content is 64 mol% and the major fatty acids are C16 : 0, C17 : 0 cyclo and C18 : 1 ω7c. It also has a unique profile of carbohydrate utilization among other species of the genus Burkholderia. The strain cannot assimilate many pentoses, hexoses and oligosaccharides, whereas it can catabolize (+)-catechin and its putative aromatic derivatives, such as 4-hydroxy-3-methoxycinnamic acid, protocatechuic acid, p-hydroxybenzoic acid, trans-p-coumaric acid and vanillic acid. Based on its morphological, physiological and chemotaxonomic characteristics, together with DNA–DNA relatedness values and 16S rRNA gene sequence comparison data, we show that strain OX-O1T represents a novel species of the genus Burkholderia, for which the name Burkholderia oxyphila sp. nov. is proposed. The type strain is OX-01T (=NBRC 105797T =DSM 22550T).

The taxonomic position of three bacterial strains, Asr22-19T, NBRC 101035 and NBRC 101041, isolated from shellfish in Japan, was determined by using a polyphasic taxonomic approach. The strains were facultatively anaerobic, motile by gliding and Gram-staining-negative slender rods. Their major respiratory quinone was menaquinone-7 and their predominant cellular fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 0 3-OH, C16 : 0 3-OH, and C16 : 0. The G+C content of the genomic DNA was 42.0–42.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strains clustered with the genus Persicobacter in the family ‘Flammeovirgaceae’. DNA–DNA relatedness values were higher than 68 % among strains Asr22-19T, NBRC 101035 and NBRC 101041, and were lower than 28 % between strain Asr22-19T and Persicobacter diffluens NBRC 15940T. The three novel strains could be differentiated from Persicobacter diffluens by several phenotypic characteristics. On the basis of these results, the novel species Persicobacter psychrovividus sp. nov. (type strain Asr22-19T=NBRC 101262T=CIP 109100T) is proposed and emended descriptions are given for the genus Persicobacter and for Persicobacter diffluens.

The taxonomic positions of two bacterial strains, ir6-1T and ir6-4T, isolated from soil collected in Iriomote Island in Japan, were determined by using a polyphasic taxonomic approach. The strains were facultatively anaerobic, motile and Gram-stain-negative rods and their optimum pH for growth was pH 4.0. Their major respiratory quinone was ubiquinone-8 and the predominant cellular fatty acids were C14 : 0, C16 : 0, C16 : 1 ω7c and C18 : 1 ω7c. The G+C content of the genomic DNA of ir6-1T and ir6-4T was 59.9 and 57.5 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences showed that the strains clustered with the genus Silvimonas in the class Betaproteobacteria. DNA–DNA similarities were lower than 53 % among ir6-1T, ir6-4T and Silvimonas terrae NBRC 100961T, and these strains could be differentiated from each other by several phenotypic characters. Based on these results, we propose the emendation of the genus Silvimonas and inclusion of two novel species, Silvimonas iriomotensis sp. nov. (type strain ir6-1T=NBRC 103188T =CGMCC 1.8859T =KCTC 22513T) and Silvimonas amylolytica sp. nov. (ir6-4T =NBRC 103189T =CGMCC 1.8860T =KCTC 22514T).

Twenty-six strains of acetic acid bacteria were isolated from fruits, flowers and related materials collected in Thailand. They were divided into three genera, Acetobacter, Gluconobacter and Asaia, by phenotypic characterization and 16S rRNA gene sequence analyses. On the basis of 16S-23S rRNA gene internal transcribed spacer (16S-23S rDNA ITS) restriction and 16S rRNA gene sequence analyses, fourteen isolates assigned to the genus Acetobacter were divided into five groups: 1) Group 1A or A. tropicalis (one isolate); 2) Group 2A or A. orientalis (four isolates); 3) Group 3A or A. pasteurianus (five isolates); 4) Group 4A or A. syzygii (one isolate); and 5) Group 5A or A. ghanensis (three isolates). The eleven isolates assigned to the genus Gluconobacter were divided into three groups: 6) Group 1B or G. frateurii (four isolates); 7) Group 2B or G. japonicus (six isolates); and 8) Group 3B or unidentified (one isolate). The remaining isolate was placed into: 9) Group 1C or unidentified, which was assigned to the genus Asaia and considered to constitute a new species on the basis of the 16S rRNA gene sequence analysis and DNA-DNA hybridization.

Forty-five acetic acid bacteria, which were isolated from fruits, flowers and other materials collected in Thailand by an enrichment culture approach, were assigned to the genusGluconobacter by phenotypic and chemotaxonomic characterisations. On the basis of 16S–23S rRNA gene ITS restriction and 16S rRNA gene sequence analyses, the forty-five isolates were grouped into five groups and identified at the specific level as follows: 1) seventeen isolates were grouped into Group A and identified asG. oxydans; 2) twelve isolates were grouped into Group B and identified asG. cerinus; 3) nine isolates were grouped into Group C and identified asG. frateurii; 4) six isolates were included into Group D and identified asG. thailandicus; 5) one isolate was grouped into Group E, characterised by a restriction pattern comprised of 667 and 48-bp fragments inAvaII digestion, differing from those of strains of Group C orG. frateurii and Group D orG. thailandicus, and unidentified.

A polyphasic study was performed to determine the taxonomic position of strain EK05(T) isolated from a root-outgrowth of Entada koshunensis, a legume available in Okinawa, Japan. Phylogenetic analysis of the 16S rRNA gene showed that the strain belongs to the genus Bradyrhizobium. Subsequent multilocus sequence analysis with ITS, glnII, recA, gyrB, and atpD sequences revealed that the isolate represents a distinct evolutionary lineage within the genus Bradyrhizobium. DNA-DNA hybridization indicated that strain EK05(T) shares61% DNA relatedness with the type strains of all six recognized species of Bradyrhizobium, confirming that this strain is a novel species within the genus. Phylogenetic trees based on symbiotic loci, nifH and nodC, also placed strain EK05(T) clearly in a novel branch. On the basis of its phylogenetic distinctiveness, we propose Bradyrhizobium iriomotense sp. nov. for strain EK05(T). The type strain is EK05(T) (= NBRC 102520(T) = LMG 24129(T)).

Phylogenetic relationships of the species belonging to the genus Myxococcus were elucidated based on the sequences of 16S rRNA genes and 16S-23S rRNA gene internal transcribed spacer (ITS) regions. The Myxococcus species were consequently classified into four distinct groups. The type strain of Myxococcus coralloides occupied an independent position (Group 1); it has been recently reclassified as Corallococcus coralloides. Group 2 comprised the type strains of both Myxococcus virescens and Myxococcus xanthus, and some strains assigned to Myxococcus flavescens. The type strain of M. flavescens was contained in Group 3 along with the strains of Myxococcus fulvus. Group 4 included the strains belonging to C. coralloides, M. fulvus, and M. stipitatus. The type strain of M. fulvus that was allocated outside Group 4 in the 16S rRNA gene tree belonged to Group 3 in the ITS tree. These results strongly suggest that the morphological characteristics of Myxococcus species are not consistent with the phylogenetic relationships. The Myxococcus species must therefore be redefined according to the phylogenetic relationships revealed in this study.

Asaia lannaensis sp. nov. was described for two strains isolated from flowers of the spider lily collected in Chiang Mai, Thailand. The isolates produced acetic acid from ethanol on ethanol/calcium carbonate agar, differing from the type strains of Asaia bogorensis, Asaia siamensis, and Asaia krungthepensis, but did not grow in the presence of 0.35% acetic acid (v/v). The new species is the fourth of the genus Asaia, the family Acetobacteraceae.

Tanticharoenia sakaeratensis gen. nov., sp. nov. is proposed for three strains isolated from soil collected in Thailand. The three strains, AC37(T), AC38, and AC39, were included within a lineage comprising the genera Asaia, Kozakia, Swaminathania, Neoasaia, Acetobacter, Gluconobacter, and Saccharibacter in a phylogenetic tree based on 16S rRNA gene sequences, but formed a quite different, independent cluster. Pair-wise sequence similarities of strain AC37(T) were 96.5-92.1% to the type strains of Acetobacter aceti, Gluconobacter oxydans, Acidomonas methanolica, Gluconacetobacter liquefaciens, Asaia bogorensis, Kozakia baliensis, Swaminathania salitolerans, Saccharibacter floricola, Neoasaia chiangmaiensis, and Granulibacter bethesdensis. The three strains had DNA base compositions comprising respectively 65.6, 64.5, and 65.6 mol % G+C with a range of 1.1 mol %, and formed a single species. Phenotypically, the three strains did not oxidize acetate or lactate, but grew on 30% D-glucose (w/v). Chemotaxonomically, they had Q-10. The type strain is AC37(T) (= BCC 15772(T) = NBRC 103193(T)).

Strain NBRC 12467 T was examined genetically, phylogenetically, phenotypically, and chemotaxonomically. The DNA G+C content of the strain was 59.5 mol%. The strain represented low levels of DNA-DNA hybridization of 49-9% to the type strains of eight Gluconobacter species. The strain formed a cluster along with the type strains of G. albidus and G. kondonii in phylogenetic trees based on 16S rRNA gene sequences. In a phylogenetic tree based on 165-23S rRNA gene ITS sequences, however, the strain formed an independent cluster from the type strains of the eight Gluconobacter species. Such phylogenetic relationships were supported by the calculated pair-wise 16S rRNA gene and 16S-23S rRNA gene ITS sequence similarities. The strain was distinguished from the type strains of the eight Gluconobacter species by 16S-23S rRNA gene ITS restriction analysis using five restriction endonucleases. The strain produced a water-soluble brown pigment and 2,5-diketo-D-gluconate from D-glucose, differing from the type strains of the eight Gluconobacter species, and acid from meso-erythritol very weakly, differing from the type strains of the remaining seven Gluconobacter species except for the type strain of G. roseus, but not from maltose, differing from the type strain of G. oxydans, and had Q-10. For the strain, which was once classified as G. oxydans subsp. sphaericus, Gluconobacter sphaericus (Ameyama 1975) comb. nov. is proposed. The type strain is NBRC 12467 T , which is also deposited as BCC 14448 T .

119‒125 (2008) * Address reprint requests to: Dr. Yuzo Yamada, BIOTEC Cul-ture Collection, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, 113 Thailand Science Park, Phaholyothin Road, Klong 1, Klong Luang, Pathumthani 12120, Thailand. E-mail: yamada333@kch.biglobe.ne.jp

The taxonomic positions of two bacterial strains, MBIC01146(T) and MBIC01099, isolated from marine environments of Japan and Palau, respectively, were determined by using a polyphasic approach. The bacteria were aerobic, motile, Gram-negative rods and formed star-shaped aggregations. The G+C content of the genomic DNA ranged from 58.5 to 58.7 mol%. The major respiratory quinone was ubiquinone-10 and the predominant cellular fatty acids were C(16 : 0), C(18 : 1)omega6c and C(18 : 1)omega7c. 16S rRNA gene sequence analyses based on both neighbour-joining and maximum-parsimony methods revealed that strains MBIC01146(T) and MBIC01099 were positioned within the cluster comprising Ruegeria atlantica and Silicibacter lacuscaerulensis within subgroup alpha-3 of the Proteobacteria. The phenotypic and chemotaxonomic characteristics of the novel strains were similar to those of Ruegeria atlantica; however, DNA-DNA hybridization tests showed that the isolates represented an independent species. The isolates could be differentiated from Ruegeria atlantica based on several characteristics. Therefore, strains MBIC01146(T) and MBIC01099 are considered to represent a novel species of the genus Ruegeria, for which the name Ruegeria mobilis sp. nov. is proposed. The type strain is MBIC01146(T) (=NBRC 101030(T)=CIP 109181(T)). An emended description of Ruegeria atlantica Uchino et al. 1999 is also given.

An aerobic, Gram-stain-negative, coccobacillus-shaped, non-endospore-forming, pink-pigmented bacterium, designated PN2T, was isolated from an olive leaf. The strain grew at 15–35 °C with an optimum temperature for growth at 30 °C, and at pH 5.0–7.5 with an optimum pH for growth at 6.0. Growth was observed in the presence of up to 1.02 % (w/v) NaCl. The major fatty acids were C19 : 0 cyclo ω8c, C16 : 0 and C18 : 1ω7c. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, unknown aminolipids, an unknown phospholipid and an unknown lipid. The respiratory quinone was ubiquinone-10. The DNA G+C content of strain PN2T was 70.4 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain PN2T was closely related to members of the genus Roseomonas and shared highest similarity with Roseomonas mucosa ATCC BAA-692T (96.5 %), Roseomonas gilardii subsp. gilardii ATCC 49956T (96.2 %) and Roseomonas gilardii subsp. rosea ATCC BAA-691T (96.2 %). Furthermore, the DNA–DNA relatedness value between strain PN2T and the closest related species R. mucosa ATCC BAA-692T was 27 %. These data allowed the phenotypic and genotypic differentiation of strain PN2T from its closest phylogenetic neighbour (R. mucosa ATCC BAA-692T). Based on phenotypic and genotypic characteristics, strain PN2T is classified as representing a novel species of the genus Roseomonas for which the name Roseomonas elaeocarpi sp. nov. is proposed. The type strain is PN2T ( = BCC 44864T = NBRC 107871T).

Three Lactobacillus-like strains, NB53T, NB446T and NB702, were isolated from traditional fermented food in Thailand. Comparative 16S rRNA gene sequence analysis indicated that these strains belong to the Lactobacillus plantarum group. Phylogenetic analysis based on the dnaK, rpoA, pheS and recA gene sequences indicated that these three strains were distantly related to known species present in the L. plantarum group. DNA–DNA hybridization with closely related strains demonstrated that these strains represented two novel species; the novel strains could be differentiated based on chemotaxonomic and phenotypic characteristics. Therefore, two novel species of the genus Lactobacillus, Lactobacillus plajomi sp. nov. (NB53T) and Lactobacillus modestisalitolerans sp. nov. (NB446T and NB702), are proposed with the type strains NB53T ( = NBRC 107333T = BCC 38054T) and NB446T ( = NBRC 107235T = BCC 38191T), respectively.

The taxonomic positions of five bacterial strains isolated from the Yaeyama Islands of Japan and ‘Microscilla arenaria’ NBRC 15982 were determined using a polyphasic taxonomic approach. 16S rRNA gene sequence analyses placed all of the strains close to the genus Flammeovirga. DNA–DNA hybridization studies, biochemical and physiological characterizations and chemotaxonomic analyses suggested that ‘M. arenaria’ NBRC 15982 and the five novel isolates represented two separate species of the genus Flammeovirga. Emendation of the genus Flammeovirga Nakagawa et al. 1997 and the species Flammeovirga aprica (Reichenbach 1989) Nakagawa et al. 1997 is proposed. In addition, ‘Microscilla arenaria’ Lewin 1969 is proposed as Flammeovirga arenaria nom. rev., comb. nov. (with the type strain NBRC 15982T=CIP 109101T) and the novel isolates are proposed as Flammeovirga yaeyamensis sp. nov. (type strain IR25-3T=NBRC 100898T=CIP 109099T).

In this paper minimal standards for the description of new genera and cultivable species in the family Flavobacteriaceae are proposed in accordance with Recommendation 30b of the Bacteriological Code (1990 Revision). In addition to specified phenotypic characteristics, the description of new species should be based on DNA-DNA hybridization data, and the placement of new taxa should be consistent with phylogenetic data derived from 16S rRNA sequencing. An emended description of the family is also proposed as several new taxa have been described since 1996. These proposals have been endorsed by the members of the Subcommittee on the taxonomy of Flavobacterium and Cytophaga-like bacteria of the International Committee on Systematics of Prokaryotes.

Phylogenetically, Cytophaga aprica and Cytophaga diffluens occupy independent positions in the flavobacter-bacteroides phylum. Both of these organisms are gram-negative rods that are motile by gliding, chemoorganotrophic, and aerobic, degrade several kinds of biomacromolecules, and inhabit marine environments. Their major isoprenoid quinone is menaquinone 7. The G+C content of the DNA of C. aprica is 35 to 37 mol%, and the G+C content of the DNA of C. diffluens is 40 to 42 mol%. In addition to constituting an independent phylogenetic lineage, each species has a distinctive cellular polyamine constitution. C. aprica is characterized by possessing cadaverine as its major polyamine, and C. diffluens is characterized by possessing spermidine, in contrast to most species of the genera Cytophaga, Flavobacterium, and Flexibacter and related organisms, which possess homospermidine. Transfer of C. aprica to the genus Flammeovirga gen. nov. as Flammeovirga aprica comb. nov. and transfer of C. diffluens to the genus Persicobacter gen. nov. as Persicobacter diffluens comb. nov. are proposed.

A 16S rRNA sequence analysis revealed that the genera Cytophaga, Flavobacterium, and Flexibacter are all polyphyletic and should be redefined and reorganized. Cytophaga hutchinsonii, the type species of the genus Cytophaga, belongs to a lineage that also contains Cytophaga aurantiaca. The genus Cytophaga is emended so that it contains only these two species, which decompose distinctly crystalline cellulose. Cytophaga salmonicolor and Cytophaga agarovorans form a lineage which is intermediate between other aerobic species and anaerobic bacteroides. Phenotypically, these organisms are characterized by being facultative anaerobes, inhabiting marine environments, and containing menaquinone-7 and spermidine. We propose that C. salmonicolor and C. agarovorans should be transferred to the genus Marinilabilia gen. nov. as Marinilabilia salmonicolor comb. nov. and Marinilabilia agarovorans comb. nov., respectively.

A Gram-negative, coccobacilli, non-spore forming and non-motile bacterium, designated PN1(T), was isolated from a banana leaf collected in Mattra island, Thailand. This isolate was observed to grow optimally at 30 °C and pH 7.0, and to grow with 0-3 % NaCl. Comparative 16S rRNA gene sequence analysis showed that strain PN1(T) is closely related to members of the genus Roseomonas, exhibiting the highest 16S rRNA gene sequence similarity to Roseomonas aestuarii JC17(T) (96.5 %). The DNA G + C content of strain PN1(T) was determined to be 69.7 mol %. Based on physiological and biochemical tests, and genotypic differences between strain PN1(T) and the validly named species of the genus Roseomonas, it is proposed that the strain be classified as a new species of Roseomonas for which the name Roseomonas musae sp. nov. is proposed. The type strain is PN1(T) (= BCC 44863(T) = NBRC 107870(T)).

Two aerobic, Gram-negative, orange pigmented and irregular rod-shaped bacteria, designated S1-05 and S1-08(T), were isolated from seawater from the Pacific Ocean. Phylogenetic analysis based on their 16S rRNA gene sequences revealed that the novel isolates could be affiliated with the genus Nonlabens of the family Flavobacteriaceae. The strains S1-05 and S1-08(T) shared 100 % pairwise sequences similarity with each other and showed less than 96.8 % similarity with the cultivated members of the genus Nonlabens. The novel isolates are phenotypically and physiologically different from strains described previously. The strains were found to be non-motile, oxidase positive, catalase positive and hydrolyzed gelatin and aesculin. The G+C contents of the DNA were determined to 41.4 and 41.7 mol% and MK-6 the predominant menaquinone. Anteiso-C15:0 and iso-C15:0 were found to be the major two cellular fatty acids. On the basis of polyphasic taxonomic studies, it was concluded that strains S1-05 and S1-08(T) represent a novel species within the genus Nonlabens, for which the name Nonlabens marina sp. nov. is proposed. The type strain of N. marina is S1-08(T) (=KCTC 23432(T) = NBRC 107738(T)).