Hyung-Jun Noh

Roseomonas aerilata sp. nov., isolated from an air sample

A polyphasic study was carried out to clarify the taxonomic position of a pink-coloured, Gram-negative bacterium isolated from air in the Suwon region of Korea. The novel strain, 5420S-30(T), grew in the temperature range of 5-35 degrees C (optimum 30 degrees C) and pH range of 5-9 (optimum pH 6-7). Growth did not occur in the presence of as little as 1 % (w/v) NaCl. It contained Q-10 as the predominant ubiquinone. The major fatty acids were C(18 : 1)omega7c, summed feature 3 (C(16 : 1)omega7c/iso-C(15 : 0) 2-OH) and C(16 : 0) (together representing 77.7 % of the total). The DNA G+C content was 72.1 mol%. The 16S rRNA gene sequence similarities between strain 5420S-30(T) and members of the genus Roseomonas were in the range 91.6-95.1 %, with the highest sequence similarities (95.1 and 94.5 %, respectively) to Roseomonas aquatica TR53(T) and Roseomonas gilardii ATCC 49956(T). On the basis of its phenotypic and genotypic characteristics, strain 5420S-30(T) represents a novel species of the genus Roseomonas, for which the name Roseomonas aerilata sp. nov. is proposed, with 5420S-30(T) (=KACC 12521(T) =DSM 19363(T)) as the type strain.

Rudanella lutea gen. nov., sp. nov., isolated from an air sample in Korea.

An orange-coloured bacterial strain, designated 5715S-11(T), was isolated from an air sample in Suwon, Republic of Korea. The strain was strictly aerobic, Gram-negative, non-spore-forming, non-flagellated and rod-shaped, frequently forming filaments. Growth of the strain was observed at 4-40 degrees C (optimum, 30 degrees C), pH 6.0-8.0 (optimum, pH 7.0) and 0-2 % (w/v) NaCl. Phylogenetically, strain 5715S-11(T) was shown to be a member of the family Spirosomaceae within the phylum Bacteroidetes. Its closest relatives were Spirosoma linguale LMG 10896(T) (87.9 % 16S rRNA gene sequence similarity) and Larkinella insperata LMG 22510(T) (86.2 % 16S rRNA gene sequence similarity). Predominant cellular fatty acids were summed feature 3 (C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH), C(16 : 1)omega5c and iso-C(15 : 0). Major polar lipids were phosphatidylethanolamine and unknown aminolipids and polar lipids. On the basis of the evidence from this polyphasic study, strain 5715S-11(T) is considered to represent a novel species of a new genus, for which the name Rudanella lutea gen. nov., sp. nov. is proposed. The type strain of Rudanella lutea is 5715S-11(T) (=KACC 12603(T) =DSM 19387(T)).

Xenophilus aerolatus sp. nov., isolated from air

A novel aerobic, Gram-negative, motile, rod-shaped bacterial strain designated 5516S-2(T) was isolated from an air sample taken in Suwon, Republic of Korea. Colonies were yellow-pigmented and circular with entire margins. 16S rRNA gene sequence analysis showed that strain 5516S-2(T) was closely related to Xylophilus ampelinus DSM 7250(T) (97.6 % sequence similarity), Variovorax soli KACC 11579(T) (97.5 %) and Xenophilus azovorans DSM 13620(T) (97.1 %). However, the phylogenetic tree indicated that strain 5516S-2(T) formed a separate clade from Xenophilus azovorans. Strain 5516S-2(T) displayed 42, 31 and 30 % DNA-DNA relatedness to the type strains of Xenophilus azovorans, Xylophilus ampelinus and V. soli, respectively. The major fatty acids (>10 % of total fatty acids) were C(16 : 0) (33.3 %), C(17 : 0) cyclo (18.8 %), C(18 : 1)omega7c (17.5 %) and summed feature 3 (comprising C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH; 13.0 %). The DNA G+C content was 69 mol%. The major quinone was ubiquinone Q-8. The predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and two unknown aminophospholipids. Genotypic and phenotypic characteristics clearly distinguished strain 5516S-2(T) from closely related species and indicated that it represents a novel species within the genus Xenophilus, for which the name Xenophilus aerolatus sp. nov. is proposed. The type strain is 5516S-2(T) (=KACC 12602(T)=DSM 19424(T)).

A New Steroidal Saponin from the Tubers of Ophiopogon japonicus and Its Protective Effect Against Cisplatin-Induced Renal Cell Toxicity

A new furostanol saponin, ophiopogonin T, was isolated from the tubers of Ophiopogon japonicus. Its structure was established by extensive spectroscopic techniques including 1D (1H and 13C) and 2D nuclear magnetic resonance (NMR) experiments (correlation spectroscopy (COSY), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond correlation (HMBC) and nuclear Overhauser effect spectroscopy (NOESY)), high-resolution electrospray ionization mass spectrometry (ESIMS), and chemical methods. Using cell-based assays, this compound was evaluated for its cytotoxic effect on cancer cell lines and its protective effect against anticancer drug-induced nephrotoxicity. Cisplatin-induced cytotoxicity in porcine kidney (LLC-PK1) cells was significantly reduced upon treatment with ophiopogonin T, without affecting human hepatoma (HepG2) cancer cell proliferation or tube formation in human umbilical vein endothelial cells (HUVECs). These results collectively reflect the beneficial effect of ophiopogonin T on the side effects of cisplatin.