Chryseobacterium edaphi sp. nov. and Chryseobacterium gilvum sp. nov., isolated from soil

Two Gram-stain-negative, aerobic, yellow and rod-shaped bacteria, designated as strains PBS4-4^T and GMJ5^T, were isolated from soil samples collected in Goyang-si and Paju-si, Gyeonggi-do, Republic of Korea. Strains PBS4-4^T and GMJ5^T were both positive for catalase and oxidase. Strain PBS4-4^T grew at 15-37 °C and pH 5.0-12.0. Strain GMJ5^T grew at 15-37 °C and pH 5.0-11.0. Neither strain required NaCl for growth. 16S rRNA sequence analysis revealed that strains PBS4-4^T and GMJ5^T form a closely related cluster with the genus Chryseobacterium. The average nucleotide identity and digital DNA-DNA hybridization values between strain PBS4-4^T and its closely related strains were 79.4-84.5% and 23.2-28.7 %, respectively. For GMJ5^T, the values were 78.3-79.3% and 22.0-22.6 %, respectively. The major fatty acids shared by both novel strains were iso-C_15 : 0 and summed feature 3 (C_16 : 1 ω7c/C_16 : 1 ω6c). Strain GMJ5^T had one other major fatty acid: iso-C_17 : 0 3OH. Based on phenotypic, genomic and phylogenetic results, strains PBS4-4^T and GMJ5^T represent novel species within the genus Chryseobacterium, and the names Chryseobacterium edaphi sp. nov. and Chryseobacterium gilvum sp. nov. are proposed, respectively. The type strain of C. edaphi is PBS4-4^T (=KACC 22882^T=TBRC 17052^T) and the type strain of C. gilvum is GMJ5^T (=KACC 22883^T=TBRC 17053^T).

Chryseobacterium paridis sp. nov., an endophytic bacterial species isolated from the root of Paris polyphylla Smith var. yunnanensis

A Gram-negative, yellow-pigmented, rod-shaped bacterial strain YIM B02567^T was isolated from the root of Paris polyphylla Smith var. yunnanensis in China. Strain YIM B02567^T grew optimally at 25-30 °C and at pH 7.0 in the absence of NaCl on nutrient agar. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain YIM B02567^T belong to the genus Chryseobacterium, and was closely related to Chryseobacterium piperi CTM^T and Chryseobacterium soli DSM 19298^T. Whole genome sequencing indicated that the genome size was 4,774,612 bp and with a G + C content of 34.5 mol%. Values of the ANI and the dDDH between strain YIM B02567^T and its closely related Chryseobacterium species were below 81.72% and 24.7%. Strain YIM B02567^T contained menaquinone-6 as the sole isoprenoid quinone, anteiso-C_15:0, iso-C_17:1 ω9c and iso-C_17:0 3-OH as major fatty acids and phosphatidylethanolamine as major polar lipid. Based on the polyphasic analyses, strain YIM B02567^T could be differentiated genotypically and phenotypically from recognized species of the genus Chryseobacterium. The isolate, therefore, represents a novel species, for which the name Chryseobacterium paridis sp. nov. is proposed. The type strain is YIM B02567^T (= CGMCC 1.18657^T).

Chryseobacterium caseinilyticum sp. nov., a casein hydrolyzing bacterium isolated from rice plant and emended description of Chryseobacterium piscicola

A novel Gram-stain-negative, aerobic, asporogenous, catalase-positive and oxidase-negative, non-motile, golden-yellow pigmented, rod-shaped bacterium with casein-degrading ability, designated strain GCR10^T, was isolated from roots of rice plants collected from a paddy field near Dongguk University, Republic of Korea. The results of subsequent 16S rRNA gene sequence analysis indicated that GCR10^T shares the highest sequence identity with Chryseobacterium piscicola VQ-6316s^T (98.3%). Strain GCR10^T grew at 2-32 °C (optimum, 25 °C), at pH 6.0-8.0 (optimum, pH 7.0) and in the presence of 0-2.0% (w/v) NaCl (optimum in the absence of NaCl). The novel strain was able to produce carotenoid and flexirubin-type pigments. The predominant menaquinone was MK-6 and the major fatty acids were identified as iso-C_{15 : 0}, iso-C_{17 : 0} 3-OH and iso-C_{17 : 1}ω9c. The polar lipids were phosphatidylethanolamine, four unidentified aminoglycolipids, two unidentified aminolipids and two unidentified glycolipids. The genome of GCR10^T is 4.3 Mb in length with a DNA G+C content of 36.5 mol%. Average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values between GCR10^T and Chryseobacterium piscicola VQ-6316s^T were 82.1, 25.2 and 84.3 %, respectively, which clearly indicates that the novel strain is distinct from its closest relative. The demand for natural biodegradable pigments isolated frominsects, plants or microorganisms is increasing day by day because of their beneficial pharmacological properties. Here, we describe a novel strain that produces two types of pigment, carotenoid and flexirubin. On the basis of the results from phenotypic, genotypic and chemotaxonomic analyses, strain GCR10^T represents a novel species of the genus Chryseobacterium, and the name Chryseobacterium caseinilyticum sp. nov. is proposed. The type strain is GCR10^T (=KACC 21707^T=NBRC 114715^T).

Draft Genome Sequence of Phosphate-Solubilizing Chryseobacterium sp. Strain ISE14, a Biocontrol and Plant Growth-Promoting Rhizobacterium Isolated from Cucumber

Chryseobacterium sp. strain ISE14 is a phosphate-solubilizing endophytic bacterium that exhibits plant growth promotion and biocontrol activities against Phytophthora blight and anthracnose on pepper.

Chryseobacterium sp. strain ISE14 is a phosphate-solubilizing endophytic bacterium that exhibits plant growth promotion and biocontrol activities against Phytophthora blight and anthracnose on pepper. Here, we report the draft genome sequence of strain ISE14, which contains genes relating to phosphate solubilization, plant growth promotion, and biocontrol traits.

Draft Genome Sequence of Chryseobacterium sp. JV274 Isolated from Maize Rhizosphere

We report the draft genome sequence of Chryseobacterium sp. JV274. This strain was isolated from the rhizosphere of maize during a greenhouse experiment. JV274 harbors genes involved in flexirubin production (darA and darB genes), bacterial competition (type VI secretion system), and gliding (bacterial motility; type IX secretion system).

Chryseobacterium cucumeris sp. nov., an endophyte isolated from cucumber (Cucumis sativus L.) root, and emended description of Chryseobacterium arthrosphaerae

The Gram-stain-negative, yellow-pigmented, rod-shaped bacterial strain GSE06^T, isolated from the surface-sterilized root of a cucumber plant grown in a field in Gunsan, Korea, was characterized by not only cultural and morphological features but also physiological, biochemical and molecular analyses. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain GSE06^T was most closely related to species of the genus Chryseobacterium. Furthermore, strain GSE06^T exhibited the highest sequence similarities with the type strains Chryseobacterium indologenes ATCC 29897^T (98.9 %), Chryseobacterium gleum ATCC 35910^T (98.8 %), Chryseobacterium arthrosphaerae CC-VM-7^T (98.7 %), Chryseobacterium contaminans C26^T (98.5 %), Chryseobacterium artocarpi UTM-3^T (98.3 %), and Chryseobacterium gallinarum 100^T (97.9 %). Average nucleotide identity values between genome sequences of strain GSE06^T and the above-mentioned reference strains ranged from 81.2 to 86.9 %, which were lower than the threshold of 95 % (corresponding to a DNA-DNA reassociation value of 70 %). The DNA G+C content of strain GSE06^T was 36.1 mol%; the predominant respiratory quinone of the strain was MK-6. The major fatty acids were iso-C15 : 0, summed feature 9 (iso-C17 : 1ω9c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and iso-C17 : 0 3-OH. The major polar lipids were phosphatidylethanolamine, three aminolipids, one aminophospholipid, four glycolipids and one unidentified lipid. These results of phenotypic and genotypic characteristics could differentiate strain GSE06^T from closely related type strains belonging to the genus Chryseobacterium. Thus, strain GSE06^T is proposed as a representative of a novel species in the genus Chryseobacterium, Chryseobacterium cucumeris sp. nov. The type strain is GSE06^T (=KACC 18798^T=JCM 31422^T).

Chryseobacterium lineare sp. nov., isolated from a limpid stream

A Gram-stain-negative, aerobic, non-motile, rod-shaped, yellow-pigmented bacterial strain, XC0022T, isolated from freshwater of a limpid stream in Zhejiang, China, was studied using a polyphasic approach. The phylogenetic analysis based on 16S rRNA gene sequences clearly showed an allocation to the genus Chryseobacterium with the highest sequence similarities of 98.0 % to Chryseobacterium taeanense PHA3-4T, 97.2 % to Chryseobacterium taihuense THMBM1T, 97.1 % to Chryseobacterium rigui CJ16T and 97.1 % to Chryseobacteriumprofundimaris DY46T. 16S rRNA gene sequence similarities to all other species of the genus Chryseobacterium were below 97.0 % (92.3-96.8 %). DNA-DNA hybridization results showed that strain XC0022T was 55.3 %, 49.8 % and 31.1 % related to C. taeanense DSM 17071T, Chryseobacteriumtaichungense DSM 17453T and Chryseobacteriumgleum JCM 2410T, respectively. The quinone system was composed only of MK-6. Strain XC0022T possessed iso-C15 : 0, iso-C17 : 0 3-OH, C18 : 1ω9c and summed feature 3 (iso-C15 : 0 2-OH/C16 : 1ω7c) as the major fatty acids. The polar lipids profile consisted of one phosphatidylethanolamine, one unidentified glycolipid, four unidentified aminolipids and two unidentified lipids. The G+C content of the genomic DNA was 29.7 mol%. On the basis of phenotypic, phylogenetic and chemotaxonomic data, strain XC0022T (=KCTC 52364T=MCCC 1K02723T) represents a novel species of the genus Chryseobacterium, for which the name Chryseobacterium lineare sp. nov. is proposed.

Development of Culture Medium for the Isolation of Flavobacterium and Chryseobacterium from Rhizosphere Soil

An effective medium designated phosphate separately autoclaved Reasoner’s 2A supplemented with cycloheximide and tobramycin (PSR2A-C/T) has been developed for the isolation of Flavobacterium and Chryseobacterium strains from the plant rhizosphere. It consists of Reasoner’s 2A agar (R2A) prepared by autoclaving phosphate and agar separately and supplementing with 50 mg L⁻¹ cycloheximide and 1 mg L⁻¹ tobramycin. A comparison was made among the following nine media: PSR2A-C/T, PSR2A-C/T supplemented with NaCl, R2A agar, R2A agar supplemented with cycloheximide and tobramycin, 1/4-strength tryptic soy agar (TSA), 1/10-strength TSA, soil-extract agar, Schaedler anaerobe agar (SAA), and SAA supplemented with gramicidin, for the recovery of Flavobacterium and Chryseobacterium strains from the Welsh onion rhizosphere. Flavobacterium strains were only isolated on PSR2A-C/T, and the recovery rate of Chryseobacterium strains was higher from PSR2A-C/T than from the eight other media. In order to confirm the effectiveness of PSR2A-C/T, bacteria were isolated from onion rhizosphere soil with this medium. Flavobacterium and Chryseobacterium strains were successfully isolated from this sample at a similar rate to that from the Welsh onion rhizosphere.