Transfer of Sejongia antarctica, Sejongia jeonii and Sejongia marina to the genus Chryseobacterium as Chryseobacterium antarcticum comb. nov., Chryseobacterium jeonii comb. nov. and Chryseobacterium marinum comb. nov

Chryseobacterium gotjawalense sp. nov. Isolated from Soil in the Volcanic Forest Gotjawal, Jeju Island

Strain wdc7T, a rod-shaped bacterium, was isolated from soil in the Gotjawal Forest on Jeju Island, South Korea. Strain wdc7T was Gram stain-negative, facultatively anaerobic, catalase- and oxidase positive, yellow pigmented, and non-flagellated. It grew at 4-37 °C and pH 5.0-8.0 in 0-3% (w/v) NaCl. 16S rRNA gene sequencing analysis revealed that strain wdc7T belonged to the genus Chryseobacterium and was most closely related to Chryseobacterium salivictor NBC 122T, with a sequence similarity of 98.51%. Menaquinone 6 was the sole respiratory quinone, and C15:0 anteiso, C15:0 iso, and summed feature 9 were the major fatty acids. The genome length was 3.30 Mbp, with a 37% G + C content. Average amino acid identity, average nucleotide identity, and digital DNA-DNA relatedness between strain wdc7T and C. salivictor NBC 122T were 93.52%, 92.80%, and 49.7%, respectively. Digital genomic and polyphasic analyses showed that strain wdc7T likely represented a new species of the genus Chryseobacterium. We proposed the name Chryseobacterium gotjawalense sp. nov., with wdc7T (= KCTC 92440T = JCM 35602T) as the type strain.

Pathological analysis and antimicrobial susceptibility of Chryseobacterium balustinum RTFCP 298 isolated from diseased rainbow trout, Oncorhynchus mykiss

In this study, six isolates of Chryseobacterium balustinum were characterized from diseased rainbow trout fingerlings. The virulence characteristics, pathogenicity, and antimicrobial susceptibility pattern of these isolates were investigated. The bacterium showed positive results for catalase, cytochrome oxidase, and aesculin hydrolysis, while negative results were obtained for DNase, gelatinase, methyl red, Voges-Proskauer's reaction, Simon citrate, Hydrogen sulphide, and starch hydrolysis. Amino acid metabolism analysis revealed the inability to metabolize arginine, lysine, and ornithine decarboxylase. Molecular characterization (16S rRNA) and phylogenetic analysis revealed the test isolates as C. balustinum, closely related to strain WLT (99.85% similarity) and C. balustinum P-27 (99.77%). Virulence assay indicated haemolytic activity and biofilm formation by the test bacterium. The challenge test confirmed moderate pathogenicity in rainbow trout and established Koch's postulates. The clinical manifestations of infection included fin erosion, eye and body surface haemorrhage, exophthalmia, and organ liquefaction. The minimum inhibitory concentrations of various antimicrobials ranged from 1 to > 256 µg mL-1. The novel synthetic antimicrobial peptides exhibited MICs of 8 to > 256 µg mL-1, suggesting a potential control method. These findings suggest that C. balustinum is an opportunistic pathogen with moderate pathogenicity in rainbow trout. Further research on the host-pathogen relationship is necessary to understand virulence characteristics and pathogenicity in aquaculture.

Pathogenic Potential and Control of Chryseobacterium Species from Clinical, Fish, Food and Environmental Sources

Chryseobacterium species are isolated and taxonomically evaluated from a wide range of sources. While C. gleum and C. indologenes have been implicated in human disease, the potential pathogenicity of numerous other species have not been investigated. The aims were therefore to evaluate 37 Chryseobacterium species and Elizabethkingia meningoseptica from environmental, food, fish, water and clinical sources for production of haemolysis, growth at 37 °C, and production of virulence enzymes. The control of these strains were investigated by determination of antimicrobial and disinfectant resistance. All the species produced α- or β-haemolysis. In terms of growth at 37 °C and production of virulence enzymes, C. soldanellicola (environmental), C. oranimense (food) and C. koreense (natural mineral water) could be potential human pathogens. Chryseobacterium piscium might be pathogenic to fish. Trimethoprim could be the most effective antimicrobial for the treatment of a Chryseobacterium species infection, while the disinfectants that contain poly-dimethyl ammonium chloride or benzalkonium chloride could be regarded as the most effective for decontamination of surfaces contaminated with Chryseobacterium species.

Kaistella flava sp. nov., isolated from Antarctic tundra soil, and emended descriptions of Kaistella yonginensis, Kaistella jeonii, Kaistella antarctica and Kaistella chaponensis

A rod-shaped, yellow-pigmented, Gram-stain-negative, non-motile and aerobic bacterium, designated 7-3A^T, was isolated from soil from King George Island, maritime Antarctica, and subjected to a polyphasic taxonomic study. Growth occurred at 4-37 °C (optimum, 20°C) and at pH 5.0-9.0 (optimum, pH 7.0-8.0). Tolerance to NaCl was up to 4 % (w/v) with optimum growth in the absence of NaCl. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 7-3A^T represented a member of the family Flavobacteriaceae. Strain 7-3A^T showed the highest sequence similarities with Kaistella yonginensis HMD 1043^T (96.65 %), Kaistella carnis NCTC 13525^T (96.53 %), Kaistella chaponensis DSM 23145^T (96.27 %), Kaistella antarctica LMG 24720^T (96.13 %) and Kaistella jeonii DSM 17048^T (96.06 %). A whole genome-level comparison of 7-3A^T with K. jeonii DSM 17048^T, K. antarctica LMG 24720^T, K. chaponensis DSM 23145^T, and Kaistella palustris DSM 21579^T revealed average nucleotide identity (ANI) values of 79.03, 82.25, 78.12, and 74.42 %, respectively. The major respiratory isoprenoid quinone was identified as MK-6 and a few ubiquinones Q-10 were identified. In addition, flexirubin-type pigments were absent. The polar lipid profile of 7-3A^T was found to contain one phosphatidylethanolamine, six unidentified aminolipids (AL) and two unidentified lipids (L). The G+C content of the genomic DNA was determined to be 34.54 mol%. The main fatty acids were iso-C_15 : 0, summed feature 9 (comprising iso-C_17 : 1ω9c and/or C_16 : 0 10-methyl), anteiso-C_15 : 0, iso-C_13 : 0 and summed feature 3 (comprising C_16 : 1ω7c and/or C_16 : 1ω6c). On the basis of the evidence presented in this study, a novel species of the genus Kaistella, Kaistella flava sp. nov., is proposed, with the type strain 7-3A^T (=CCTCC AB 2016141^T= KCTC 52492^T). Emended descriptions of Kaistella yonginensis, Kaistella jeonii, Kaistella antarctica and Kaistella chaponensis are also given.

Division of the genus Chryseobacterium: Observation of discontinuities in amino acid identity values, a possible consequence of major extinction events, guides transfer of nine species to the genus Epilithonimonas, eleven species to the genus Kaistella, and three species to the genus Halpernia gen. nov., with description of Kaistella daneshvariae sp. nov. and Epilithonimonas vandammei sp. nov. derived from clinical specimens

The genus Chryseobacterium in the family Weeksellaceae is known to be polyphyletic. Amino acid identity (AAI) values were calculated from whole-genome sequences of species of the genus Chryseobacterium, and their distribution was found to be multi-modal. These naturally-occurring non-continuities were leveraged to standardise genus assignment of these species. We speculate that this multi-modal distribution is a consequence of loss of biodiversity during major extinction events, leading to the concept that a bacterial genus corresponds to a set of species that diversified since the Permian extinction. Transfer of nine species (Chryseobacterium arachidiradicis, Chryseobacterium bovis, Chryseobacterium caeni, Chryseobacterium hispanicum, Chryseobacterium hominis, Chryseobacterium hungaricum,, Chryseobacterium pallidum and Chryseobacterium zeae) to the genus Epilithonimonas and eleven (Chryseobacterium anthropi, Chryseobacterium antarcticum, Chryseobacterium carnis, Chryseobacterium chaponense, Chryseobacterium haifense, Chryseobacterium jeonii, Chryseobacterium montanum, Chryseobacterium palustre, Chryseobacterium solincola, Chryseobacterium treverense and Chryseobacterium yonginense) to the genus Kaistella is proposed. Two novel species are described: Kaistella daneshvariae sp. nov. and Epilithonimonas vandammei sp. nov. Evidence is presented to support the assignment of Planobacterium taklimakanense to a genus apart from Chryseobacterium, to which Planobacterium salipaludis comb nov. also belongs. The novel genus Halpernia is proposed, to contain the type species Halpernia frigidisoli comb. nov., along with Halpernia humi comb. nov., and Halpernia marina comb. nov.

Genome-Based Taxonomic Classification of Bacteroidetes

The bacterial phylum Bacteroidetes, characterized by a distinct gliding motility, occurs in a broad variety of ecosystems, habitats, life styles, and physiologies. Accordingly, taxonomic classification of the phylum, based on a limited number of features, proved difficult and controversial in the past, for example, when decisions were based on unresolved phylogenetic trees of the 16S rRNA gene sequence. Here we use a large collection of type-strain genomes from Bacteroidetes and closely related phyla for assessing their taxonomy based on the principles of phylogenetic classification and trees inferred from genome-scale data. No significant conflict between 16S rRNA gene and whole-genome phylogenetic analysis is found, whereas many but not all of the involved taxa are supported as monophyletic groups, particularly in the genome-scale trees. Phenotypic and phylogenomic features support the separation of Balneolaceae as new phylum Balneolaeota from Rhodothermaeota and of Saprospiraceae as new class Saprospiria from Chitinophagia. Epilithonimonas is nested within the older genus Chryseobacterium and without significant phenotypic differences; thus merging the two genera is proposed. Similarly, Vitellibacter is proposed to be included in Aequorivita. Flexibacter is confirmed as being heterogeneous and dissected, yielding six distinct genera. Hallella seregens is a later heterotypic synonym of Prevotella dentalis. Compared to values directly calculated from genome sequences, the G+C content mentioned in many species descriptions is too imprecise; moreover, corrected G+C content values have a significantly better fit to the phylogeny. Corresponding emendations of species descriptions are provided where necessary. Whereas most observed conflict with the current classification of Bacteroidetes is already visible in 16S rRNA gene trees, as expected whole-genome phylogenies are much better resolved.

Polyphasic characterization reveals the presence of novel fish-associated Chryseobacterium spp. in the Great Lakes of North America

Recent reports suggest an emergence of novel Chryseobacterium spp. associated with aquaculture-reared fish worldwide. Herein, we report on multiple Chryseobacterium spp. infecting Great Lakes fishes that are highly similar to previously detected isolates from Europe, Africa, and Asia but have never before been reported in North America. Polyphasic characterization, which included extensive physiological, morphological, and biochemical analyses, fatty acid profiling, and phylogenetic analyses based upon partial 16S rRNA gene sequences, highlighted the diversity of Great Lakes' fish-associated chryseobacteria and also suggested that at least 2 taxa represent potentially novel Chryseobacterium spp. Screening for the ability of representative chryseobacteria to elicit lesions in experimentally challenged fish showed that they induced varying degrees of pathology, some of which were severe and resulted in host death. Median lethal dose (LD50) experiments for the isolate that elicited the most extensive pathology (Chryseobacterium sp. T28) demonstrated that the LD50 exceeded 4.5 × 108 cfu, thereby suggesting its role as a facultative fish-pathogenic bacterium. Histopathological changes in T28-infected fish included epithelial hyperplasia of the secondary lamellae and interlamellar space that resulted in secondary lamellar fusion, monocytic infiltrate, and mucus cell hyperplasia, all of which are consistent with branchitis, along with monocytic myositis, hemorrhage within the muscle, liver, adipose tissue, and ovaries, spongiosis of white matter of the brain, multifocal edema within the granular cell layer of the cerebellar cortex, and renal tubular degeneration and necrosis. The findings of this study underscore the widespread presence of chryseobacteria infecting Great Lakes fish.

Emerging flavobacterial infections in fish: A review

Flavobacterial diseases in fish are caused by multiple bacterial species within the family Flavobacteriaceae and are responsible for devastating losses in wild and farmed fish stocks around the world. In addition to directly imposing negative economic and ecological effects, flavobacterial disease outbreaks are also notoriously difficult to prevent and control despite nearly 100 years of scientific research. The emergence of recent reports linking previously uncharacterized flavobacteria to systemic infections and mortality events in fish stocks of Europe, South America, Asia, Africa, and North America is also of major concern and has highlighted some of the difficulties surrounding the diagnosis and chemotherapeutic treatment of flavobacterial fish diseases. Herein, we provide a review of the literature that focuses on Flavobacterium and Chryseobacterium spp. and emphasizes those associated with fish.

Chryseobacterium angstadtii sp. nov., isolated from a newt tank

As part of an undergraduate microbiology course, a yellow-orange-pigmented, Gram-staining negative, rod-shaped, non-motile bacterial strain was isolated from a glass tank housing several red-spotted newts (Notophthalmus viridescens). The sequence of the 16S rRNA gene of this strain, designated KM(T), was 97.4-98.0 % similar to those of the type strains of Chryseobacterium luteum, C. shigense and C. vrystaatense, while the similarity levels for protein-coding genes were less than 94.7 % for rpoB, less than 92.1 % for groEL and less than 87.1 % for gyrB. These values are lower than for many other established distinct species. Polyphasic characterization and comparison to these relatives revealed that strain KM(T) was similar to other Chryseobacterium strains in that it contained MK-6 as its major respiratory quinone and phosphatidylethanolamine as the most abundant polar lipid, produced flexirubin-type pigments, oxidase and catalase and primarily contained the fatty acids iso-C15 : 0, iso-C17 : 1ω9c, iso-C17 : 0 3-OH and summed feature 3 (comprising C16 : 1ω6c and/or C16 : 1ω7c). Based on the results of this study, strain KM(T) represents a novel species, for which the name Chryseobacterium angstadtii sp. nov. is proposed. The type strain is KM(T) ( = ATCC BAA-2160(T) = NRRL B-59516(T) = KCTC 23297(T)).

DNA-DNA hybridization study of strains of Chryseobacterium, Elizabethkingia and Empedobacter and of other usually indole-producing non-fermenters of CDC groups IIc, IIe, IIh and IIi, mostly from human clinical sources, and proposals of Chryseobacterium bernardetii sp. nov., Chryseobacterium carnis sp. nov., Chryseobacterium lactis sp. nov., Chryseobacterium nakagawai sp. nov. and Chryseobacterium taklimakanense comb. nov

The taxonomic classification of 182 phenotypically similar isolates was evaluated using DNA-DNA hybridization and 16S rRNA gene sequence analysis. These bacterial isolates were mainly derived from clinical sources; all were Gram-negative non-fermenters and most were indole-producing. Phenotypically, they resembled species from the genera Chryseobacterium, Elizabethkingia or Empedobacter or belonged to CDC groups IIc, IIe, IIh and IIi. Based on these analyses, four novel species are described: Chryseobacterium bernardetii sp. nov. (type strain NCTC 13530(T) = CCUG 60564(T) = CDC G229(T)), Chryseobacterium carnis sp. nov. (type strain NCTC 13525(T) = CCUG 60559(T) = CDC G81(T)), Chryseobacterium lactis sp. nov. (type strain NCTC 11390(T) = CCUG 60566(T) = CDC KC1864(T)) and Chryseobacterium nakagawai sp. nov. (type strain NCTC 13529(T) = CCUG 60563(T) = CDC G41(T)). The new combination Chryseobacterium taklimakanense comb. nov. (type strain NCTC 13490(T) = X-65(T) = CCTCC AB 208154(T) = NRRL B-51322(T)) is also proposed to accommodate the reclassified Planobacterium taklimakanense.

Chryseobacterium ginsengisoli sp. nov., isolated from the rhizosphere of ginseng and emended description of Chryseobacterium gleum

Strain DCY 63T, isolated from the rhizosphere of ginseng, was a Gram-reaction-negative, strictly aerobic, non-motile, catalase- and oxidase-positive rod. 16S rRNA gene sequence analysis revealed that strain DCY 63T belonged to the genus Chryseobacterium and was closely related to Chryseobacterium indoltheticum LMG 4025T (98.1 %), Chryseobacterium ginsenosidimutans THG 15T (98.0 %) and Chryseobacterium scophthalmum LMG 13028T (97.1 %). The major polar lipids of strain DCY 63T were phosphatidylethanolamine (PE), four unidentified aminolipids and three unidentified polar lipids, and the major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and summed feature 9 (iso-C17 : 1ω9c and/or C16 : 0 10-methyl). The predominant isoprenoid quinone of strain DCY 63T was MK-6 and the G+C content of the genomic DNA was 31.6 mol%. The DNA–DNA relatedness values between strain DCY 63T and C. indoltheticum LMG 4025T, C. ginsenosidimutans THG 15T and C. scophthalmum LMG 13028T were less than 30 %. On the basis of these data, strain DCY 63T is considered to represent a novel species of the genus Chryseobacterium , for which the name Chryseobacterium ginsengisoli sp. nov. is proposed. The type strain is DCY 63T ( = KCTC 23760T = JCM 18019T). An emended description of Chryseobacterium gleum is also proposed.

Chryseobacterium frigidisoli sp. nov., a psychrotolerant species of the family Flavobacteriaceae isolated from sandy permafrost from a glacier forefield

During diversity studies of the glacier forefields of the Larsemann Hills, East Antarctica, a novel psychrotolerant, non-motile Gram-negative, shiny yellow, rod-shaped, aerobic bacterium, designated strain PB4(T) was isolated from a soil sample. Strain PB4(T) produces indole from tryptophan and hydrolyses casein. It grows between 0 and 25 °C with an optimum growth temperature of 20 °C. A wide range of substrates are used as sole carbon sources and acid is produced from numerous carbohydrates. The major menaquinone is MK-6. Identified polar lipids are ethanolamines and ornithine lipids. Major fatty acids (>10 %) are iso-C15 : 0 (13.0 %) and iso-2OH-C15 : 0 (51.2 %). G+C content is 33.7 mol%. The polyamine pattern is composed of sym-homospermidine (25.1 µmol g(-1) dry weight), minor amounts of cadaverine (0.2 µmol g(-1) dry weight) and spermidine (0.4 µmol g(-1) dry weight) and traces of putrescine and spermine (<0.1 µmol g(-1) dry weight). Strain PB4(T) had highest 16S rRNA gene similarities with the type strains of Chryseobacterium humi (97.0 %) and Chryseobacterium marinum (96.5 %). Considering phenotypic and genotypic characterization, strain PB4(T) represents a novel species in the genus Chryseobacterium (family Flavobacteriaceae), for which the name Chryseobacterium frigidisoli sp. nov. is proposed. The type strain is PB4(T) ( = DSM 26000(T) = LMG 27025(T)).

Chryseobacterium rigui sp. nov., isolated from an estuarine wetland

A bacterium, designated strain CJ16(T), was isolated from the estuarine wetland of the Han River. Cells of the isolate were yellow-pigmented, Gram-stain-negative, non-motile and rod-shaped. Growth of strain CJ16(T) was observed in TSB at 5-37 °C (optimum 30 °C), at pH 5.0-9.0 (optimum pH 6.0) and with 0-3 % (w/v) NaCl (optimum 0 %). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain CJ16(T) was most closely related to Chryseobacterium hagamense KCTC 22545(T) (97.2 % 16S rRNA gene sequence similarity). Genomic relatedness based on DNA-DNA hybridization between strain CJ16(T) and C. hagamense KCTC 22545(T) was 23 % (strain CJ16(T) as probe) and 19 % (strain KCTC 22545(T) as probe). Chemotaxonomic analysis revealed that strain CJ16(T) possessed MK-6 as the major isoprenoid quinone and sym-homospermidine as the predominant polyamine. The predominant fatty acids were iso-C15 : 0 (26.9 %), iso-C17 : 0 3-OH (16.8 %) and summed feature 9 (comprising C16 : 0 10-methyl and/or iso-C17 : 1ω9c; 10.5 %). The DNA G+C content of strain CJ16(T) was 37.9 mol%. Based on phenotypic, genotypic and phylogenetic studies, strain CJ16(T) represents a novel species of the genus Chryseobacterium, for which the name Chryseobacterium rigui sp. nov. is proposed. The type strain is CJ16(T) ( = KACC 16560(T)  = JCM 18078(T)).

Chryseobacterium chaponense sp. nov., isolated from farmed Atlantic salmon (Salmo salar)

Two bacterial strains, designated Sa 1147-06T and Sa 1143-06, were isolated from Atlantic salmon (Salmo salar) farmed in Lake Chapo, Chile, and were studied using a polyphasic approach. Both isolates were very similar; cells were rod-shaped, formed yellow-pigmented colonies and were Gram-reaction-negative. Based on 16S rRNA gene sequence analysis, strains Sa 1147-06T and Sa 1143-06 shared 100 % sequence similarity and showed 98.9 and 97.5 % sequence similarity to Chryseobacterium jeonii AT1047T and Chryseobacterium antarcticum AT1013T, respectively. Sequence similarities to all other members of the genus Chryseobacterium were below 97.3 %. The major fatty acids of strain Sa 1147-06T were iso-C13 : 0, iso-C15 : 0, anteiso-C15 : 0 and iso-C17 : 1 ω9c, with iso-C15 : 0 3-OH, iso-C16 : 0 3-OH and iso-C17 : 0 3-OH constituting the major hydroxylated fatty acids. DNA–DNA hybridizations with C. jeonii JMSNU 14049T and C. antarcticum JMNSU 14040T gave relatedness values of 20.7 % (reciprocal 15.1 %) and 15.7 % (reciprocal 25.7 %), respectively. Together, the DNA–DNA hybridization results and differentiating biochemical properties showed that strains Sa 1147-06T and Sa 1143-06 represent a novel species, for which the name Chryseobacterium chaponense sp. nov. is proposed. The type strain is Sa 1147-06T (=DSM 23145T =CCM 7737T).

Chryseobacterium yonginense sp. nov., isolated from a mesotrophic artificial lake

A Gram-staining-negative, non-motile, yellow-pigmented bacterial strain, designated HMD1043(T), was isolated from a mesotrophic artificial lake in Korea. The major fatty acids were anteiso-C(15 : 0) (28.3 %), iso-C(15 : 0) (22.9 %), summed feature 9 (comprising iso-C(17 : 1)ω9c and/or 10-methyl C(16 : 0); 8.8 %) and iso-C(13 : 0) (5.3 %). The DNA G+C content was 31.3 mol%. A phylogenetic tree based on 16S rRNA gene sequences showed that strain HMD1043(T) formed a lineage within the genus Chryseobacterium and was most closely related to Chryseobacterium antarcticum AT1013(T) (96.8 % 16S rRNA gene sequence similarity) and Chryseobacterium jeonii AT1047(T) (96.4 %). On the basis of the evidence presented in this study, strain HMD1043(T) is described as belonging to a novel species of the genus Chryseobacterium, for which the name Chryseobacterium yonginense sp. nov. is proposed. The type strain is HMD1043(T) ( = KCTC 22744(T)  = CECT 7547(T)).

Chryseobacterium xinjiangense sp. nov., isolated from alpine permafrost

Strain TSBY 67(T) was isolated during a study on the phylogenetic diversity of culturable bacteria from alpine permafrost in Tianshan Mountains, China. On the basis of 16S rRNA gene sequence analysis, strain TSBY 67(T) was closely related to members of the genus Chryseobacterium and exhibited 96.8 % 16S rRNA gene sequence similarity to Chryseobacterium aquaticum 10-46(T) and Chryseobacterium soldanellicola PSD 1-4(T). Strain TSBY 67(T) grew aerobically, at 4-37 °C, with 0-2 % NaCl and at pH 6-8. Cells were Gram-staining negative, non-motile and non-spore-forming rods. The dominant cellular fatty acids were iso-C(15 : 0) (26.9 %), iso-C(17 : 0) 3-OH (16.1 %) and iso-C(17 : 1)ω9c (15.4 %). The G+C content of the DNA was 33.5 mol%. Strain TSBY 67(T) was distinguishable from its closest phylogenetic neighbours by a combination of phenotypic characteristics. Therefore, strain TSBY 67(T) represents a novel species of the genus Chryseobacterium, for which the name Chryseobacterium xinjiangense sp. nov. is proposed. The type strain is TSBY 67(T) ( = NRRL B-51308(T) = CCTCC AB 207183(T)).

Chryseobacterium palustre sp. nov. and Chryseobacterium humi sp. nov., isolated from industrially contaminated sediments

Two Gram-staining-negative bacterial strains, designated 3A10T and ECP37T, were isolated from sediment samples collected from an industrially contaminated site in northern Portugal. These two organisms were rod-shaped, non-motile, aerobic, catalase- and oxidase-positive and formed yellow colonies. The predominant fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C17 : 1 ω9c and iso-C17 : 0 3-OH. The G+C content of the DNA of strains 3A10T and ECP37T was 43 and 34 mol%, respectively. The major isoprenoid quinone of the two strains was MK-6. 16S rRNA gene sequence analysis revealed that strains 3A10T and ECP37T were members of the family Flavobacteriaceae and were related phylogenetically to the genus Chryseobacterium. Strain 3A10T showed 16S rRNA gene sequence similarity values of 97.2 and 96.6 % to the type strains of Chryseobacterium antarcticum and Chryseobacterium jeonii, respectively; strain ECP37T showed 97.3 % similarity to the type strain of Chryseobacterium marinum. DNA–DNA hybridization experiments revealed levels of genomic relatedness of <70 % between strains 3A10T and ECP37T and between these two strains and the type strains of C. marinum, C. antarcticum and C. jeonii, justifying their classification as representing two novel species of the genus Chryseobacterium. The names proposed for these organisms are Chryseobacterium palustre sp. nov. (type strain 3A10T =LMG 24685T =NBRC 104928T) and Chryseobacterium humi sp. nov. (type strain ECP37T =LMG 24684T =NBRC 104927T).

Novel ultramicrobacterial isolates from a deep Greenland ice core represent a proposed new species, Chryseobacterium greenlandense sp. nov

Three novel orange, ultramicrobacterial isolates, UMB10, UMB14, and UMB34(T) were isolated from enrichment cultures inoculated with a melted 3,043 m deep Greenland ice core sample. Phylogenetic analysis of the 16S rRNA gene sequences indicated that the isolates belonged to a single species within the genus Chryseobacterium. They were most closely related to Chryseobacterium aquaticum (99.3%), Chryseobacterium soli (97.1%), and Chryseobacterium soldanellicola (96.9%). Genomic hybridization showed low levels of relatedness between UMB34(T) and C. aquaticum and C. soldanellicola (19-30%) and C. soli and Chryseobacterium jejuense (45-56%). Comparative genomic fingerprinting analysis using the enterobacterial repetitive intergenic consensus (ERIC) sequence showed nearly identical banding patterns for the three isolates and these patterns were distinct from those of C. aquaticum, C. soldanellicola, C. soli, and C. jejuense. The cells were short rods, lacked flagella, had cell volumes of <0.1 mum(3), formed buds and smaller protrusions (blebs), produced copious extracellular material and a flexirubin type pigment. UMB34(T) produced acids from carbohydrates and utilized glucose and maltose although it did not assimilate mannose. The DNA G + C was 39.6-41.6 mol%. Based on the differences from validly named Chryseobacterium species, it was concluded that these isolates represent a new species for which the name, Chryseobacterium greenlandense is proposed. The type strain is UMB34(T) (=CIP 110007T = NRRL B-59357).

Chryseobacterium treverense sp. nov., isolated from a human clinical source

A yellow-pigmented, Gram-reaction-negative bacterium isolated from a human clinical source was investigated using a polyphasic approach in order to clarify its taxonomic status. Comparative 16S rRNA gene sequence analysis showed that the new isolate constituted a distinct phyletic line within the genus Chryseobacterium, displaying >2.8 % sequence divergence with recognized species of this genus. The generic assignment was confirmed by chemotaxonomic data which revealed a fatty acid profile consisting of straight-chain saturated, monounsaturated and branched-chain fatty acids of iso-/anteiso-types as well as 3-hydroxylated fatty acids; a menaquinone with six isoprene units (MK-6) as the predominant respiratory quinone and sym-homospermidine as the predominant polyamine. The novel isolate could be distinguished from other members of the genus Chryseobacterium by a set of distinct biochemical properties. On the basis of phenotypic and phylogenetic evidence, it is proposed that the new isolate represents a novel species of the genus Chryseobacterium for which the name Chryseobacterium treverense sp. nov. is proposed. The type strain is IMMIB L-1519(T) (=DSM 22251(T)=CCUG 57657(T)).