Paraburkholderia translucens sp. nov. and Paraburkholderia sejongensis sp. nov., isolated from grassland soil and showing plant growth promoting potential.

Two Gram-negative bacterial strains designated MMS20-SJTN17T and MMS20-SJTR3T were isolated from a grassland soil sample, and taxonomically characterized using a polyphasic approach. The 16S rRNA gene sequence analysis indicates that both strains belong to the genus Paraburkholderia of the class Betaproteobacteria, with strain MMS20-SJTN17T being mostly related to Paraburkholderia sprentiae WSM5005T (96.45 % sequence similarity) and strain MMS20-SJTR3T to Paraburkholderia tuberum STM678T (98.59 % sequence similarity). MMS20-SJTN17T could grow at 15-40 °C (optimum, 25-30 °C) and at pH 6.0-8.0 (optimum, pH 6.0-7.0), whereas MMS20-SJTR3T could grow at 10-40 °C (optimum, 30-37 °C) and at pH 6.0-8.0 (optimum, pH 6.0). Both strains tolerated up to 1 % (w/v) NaCl (optimum, 0 %). The major fatty acids of MMS20-SJTN17T were C16 : 0 and C19 : 0 cyclo ω8c, and those of MMS20-SJTR3T were C17 : 0 cyclo and a summed feature comprising C18 : 1 ω7c and/or C18 : 1 ω6c. The major isoprenoid quinone of both strains was ubiquinone-8 and the diagnostic polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. Regarding plant growth promoting potential, both strains were capable of producing indole acetic acid, siderophore and 1-aminocyclopropane-1-carboxylic acid deaminase, and also showed phosphate-solubilizing activity. A genome-based comparison using orthologous average nucleotide identity and digital DNA-DNA hybridization values indicates that strain MMS20-SJTN17T shares highest relatedness with Paraburkholderia monticola JC2948T and MMS20-SJTR3T with Paraburkholderia antibiotica G-4-1-8T, with values clearly below the cutoffs for species distinction. Examination of biosynthetic gene clusters responsible for secondary metabolite production reveals unique characteristics distinguishing each strain from closely related Paraburkholderia species. On the basis of genotypic, phenotypic, chemotaxonomic and phylogenomic data, each strain should be classified as a novel species of the genus Paraburkholderia, for which the names Paraburkholderia translucens sp. nov. (=MMS20-SJTN17T=LMG 32366T=KCTC 82783T) and Paraburkholderia sejongensis sp. nov. (=MMS20-SJTR3T=LMG 32367T=KCTC 82784T) are proposed.

Description of Chryseobacterium fluminis sp. nov., a keratinolytic bacterium isolated from a freshwater river.

A Gram-stain-negative, aerobic, rod-shaped bacterial strain, designated MMS21-Ot14T, was isolated from a freshwater river, and shown to represent a novel species of the genus Chryseobacterium on the basis of the results from a polyphasic approach. The 16S rRNA gene sequence analysis revealed that MMS21-Ot14T represented a member of the genus Chryseobacterium of the family Weeksellaceae and was closely related to Chryseobacterium hagamense RHA2-9T (97.52 % sequence similarity), Chryseobacterium gwangjuense THG A18T (97.46 %) and Chryseobacterium gregarium P 461/12T (97.27 %). The optimal growth of MMS21-Ot14T occurred at 25-30 °C, pH 6.0-7.0 and in the absence of NaCl. MMS21-Ot14T was capable of hydrolysing casein, starch, DNA, Tween 20 and tyrosine. The strain also showed keratinolytic activity with keratin azure and decolourising activity with remazol brilliant blue R (RBBR), which indicated potential ability to degrade keratin and lignin. The main polar lipids of MMS21-Ot14T were phosphatidylethanolamine, unidentified aminophospholipids, unidentified aminolipids, an unidentified phospholipid and several unidentified lipids. The predominant fatty acids of MMS21-Ot14T were iso-C15 : 0 and iso-C17 : 0 3-OH, and the major isoprenoid quinone was menaquinone 6 (MK-6). The whole genome of MMS21-Ot14T was 5 062 016 bp in length with a DNA G+C content of 37.7 %. The average nucleotide identity and digital DNA-DNA hybridisation values between MMS21-Ot14T and phylogenetically related members of the genus Chryseobacterium were well below the threshold values for species delineation. It is evident from the results of this study that MMS21-Ot14T should be classified as representing a novel species of the genus Chryseobacterium, for which the name Chryseobacterium fluminis sp. nov. (type strain, MMS21-Ot14T = KCTC 92255T = LMG 32529T) is proposed.

Paenarthrobacter aromaticivorans sp. nov., a paraoxon-degrading bacterium isolated from red pepper cultivation soil.

A bacterial strain designated MMS21-TAE1-1T, capable of degrading paraoxon, was isolated from red pepper soil (36° 25' 26.0″ N, 126° 25' 47.0″ E) and subjected to polyphasic taxonomic characterisation. MMS21-TAE1-1T was an aerobic, non-motile and Gram-stain-positive bacterium. MMS21-TAE1-1T showed growth at 10-37 °C (optimum, 30 °C), at pH 4-10 (optimum, pH 7) and in the presence of 0-6 % NaCl (optimum, 0 %). On the basis of the results of 16S rRNA gene sequence analysis, MMS21-TAE1-1T could be assigned to the genus Paenarthrobacter and shared the highest sequence similarities with Paenarthrobacter aurescens NBRC 12136T (99.72 %), then with Paenarthrobacter nitroguajacolicus G2-1T (99.65 %) and Paenarthrobacter ilicis DSM 20138T (99.17 %). However, the results of genome-based comparison using orthologous average nucleotide identity (orthoANI) and digital DNA-DNA hybridisation indicated that MMS21-TAE1-1T could be readily distinguished from all species of the genus with validly published names. The predominant menaquinone of MMS21-TAE1-1T was MK-9(H2). The diagnostic polar lipids were diphosphatidylglycerol and phosphatidylinositol, and unidentified glycolipids were also present. The major fatty acids were anteiso-C15 : 0, anteiso-C17 : 0, iso-C16 : 0 and iso-C15 : 0. The chemotaxonomic properties of MMS21-TAE1-1T were generally consistent with those of members of the genus Paenarthrobacter. The genome of MMS21-TAE1-1T contained genes related to degradation of aromatic compounds. It is evident from the results of this study that strain MMS21-TAE1-1T merits recognition as representing a novel species of the genus Paenarthrobacter, for which the name Paenarthrobacter aromaticivorans sp. nov. is proposed. The type strain is MMS21-TAE1-1T (=KCTC 49652T = LMG 32368T).

Flavobacterium humidisoli sp. nov., isolated from riverside soil.

A novel Gram-stain-negative, yellow-pigmented, non-motile and rod-shaped bacterial strain designated MMS21-Er5T was isolated and subjected to polyphasic taxonomic characterization. MMS21- Er5T could grow at 4-34 °C (optimum, 30 °C), at pH 6-8 (optimum, pH 7) and in the presence of 0-2% NaCl (optimum, 1 %). The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that MMS21- Er5T showed low levels of sequence similarities with other species, as the highest similarity of 97.83 % was observed with Flavobacterium tyrosinilyticum THG DN8.8T, then 97.68 % with 'Flavobacterium ginsengiterrae' DCY 55 and 97.63 % with Flavobacterium banpakuense 15F3T, which were well below the suggested cutoff for species distinction. The whole genome sequence of MMS21-Er5T consisted of a single contig of 5.63 Mbp, and the DNA G+C content was 34.06 mol%. The in-silico DNA-DNA hybridization and orthologous average nucleotide identity values were highest with Flavobacterium tyrosinilyticum KCTC 42726T (45.7 and 91.92% respectively). The predominant respiratory quinone for the strain was menaquinone-6 (MK-6), the major cellular fatty acid was iso-C15 : 0, and the diagnostic polar lipids were phosphatidylethanolamine and phosphatidyldiethanolamine. The combination of physiological and biochemical tests clearly distinguished the strain from related species of the genus Flavobacterium. On the basis of these results, strain MMS21-Er5T evidently represents a novel species of the genus Flavobacterium, for which the name Flavobacterium humidisoli sp. nov. is proposed (type strain=MMS21-Er5T=KCTC 92256T =LMG 32524T).

Time course of symptom disappearance after microvascular decompression for hemifacial spasm.

OBJECTIVE: This study is to investigate time course of symptom disappearance in patients whose spasm relieved completely after microvascular decompression (MVD). METHODS: Of 115 patients with hemifacial spasm (HFS) who underwent MVD from April 2003 to December 2006, 89 patients who had no facial paralysis after operation and showed no spasm at last follow-up more than 1.5 years after operation were selected. Symptom disappearance with time after MVD was classified into type 1 (symptom disappearance right after operation), type 2 (delayed symptom disappearance) and type 3 (unusual symptom disappearance). Type 2 was classified into type 2a (with postoperative silent period) and type 2b (without silent period). RESULTS: Type 1, type 2a, type 2b and type 3 were 38.2%, 48.37%, 12.4% and 1.1%, respectively. Delayed disappearance group (type 2) was 60.7%. Post-operative symptom duration in all cases ranged from 0 to 900 days, average was 74.6 days and median was 14 days. In case of type 2, average post-operative symptom duration was 115.1 days and median was 42 days. Five and 3 patients required more than 1 year and 2 years, respectively, until complete disappearance of spasm. In type 2a, postoperative silent period ranged from 1 to 10 days, with an average of 2.4 days. CONCLUSION: Surgeons should be aware that delayed symptom disappearance after MVD for HFS is more common than it has been reported, silent period can be as long as 10 days and time course of symptom disappearance is various as well as unpredictable.