Aquimarina versatilis sp. nov., isolated from seashore sand, and emended description of the genus Aquimarina.

Strain CBA3207T, a novel Gram-stain-negative, aerobic and rod-shaped bacterium, was isolated from the seashore sand of Jeju island in South Korea. Strain CBA3207T grew optimally at 25-30 °C and pH 7.0-7.5 with 3.0-4.0 % (w/v) NaCl. It was catalase-positive, oxidase-negative, and hydrolysed starch, gelatin, and Tweens 20, 40 and 80. The 16S rRNA gene sequence of strain CBA3207T showed 96.0, 95.6, 95.6, 95.5 and 95.5 % similarity to that of Aquimarinamytili PSC33T, Aquimarinaagarivorans HQM9T, Aquimarinalatercula DSM 2041T, Aquimarinaintermedia KMM 6258T and Aquimarinaamphilecti 92VT, respectively. The major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, iso-C15 : 1 G and summed feature 9 (10-methyl C16 : 0 and/or iso-C17 : 1ω9c). The major respiratory quinone was menaquinone-6, and the major polar lipids were phosphatidylethanolamine, an unidentified aminolipid and six unidentified lipids. The G+C content of the genomic DNA was 38.8 mol%. Based on phenotypic, genotypic and phylogenetic analyses, strain CBA3207T represents a novel species in the genus Aquimarina, for which the name Aquimarinaversatilissp. nov. is proposed. The type strain is CBA3207T (=KACC 17666T=JCM 19528T).

Differential Metabolic Profiles during the Developmental Stages of Plant-Parasitic Nematode Meloidogyne incognita.

Meloidogyne incognita is a common root-knot nematode with a wide range of plant hosts. We aimed to study the metabolites produced at each stage of the nematode life cycle to understand its development. Metabolites of Meloidogyne incognita were extracted at egg, J2, J3, J4, and female stages and 110 metabolites with available standards were quantified using CE-TOF/MS. Analyses indicated abundance of stage-specific metabolites with the exception of J3 and J4 stages which shared similar metabolic profiles. The egg stage showed increased abundance in glycolysis and energy metabolism related metabolites while the J2 metabolites are associated with tissue formation, motility, and neurotransmission. The J3 and J4 stages indicated amino acid metabolism and urea cycle- related metabolites. The female stage was characterized with polyamine synthesis, antioxidant activity, and synthesis of reproduction related metabolites. Such metabolic profiling helps us understand the dynamic physiological changes related to each developmental stage of the root-knot nematode life cycle.

Wohlfahrtiimonas larvae sp. nov., isolated from the larval gut of Hermetia illucens (Diptera: Stratiomyidae).

A novel, Gram-negative, facultative anaerobic, motile and short rod-shaped bacterium, strain KBL006(T) was isolated from the larval gut of Hermetia illucens, Black soldier fly. The 16S rRNA gene sequence of strain KBL006(T) showed 96.4 % similarity to that of Wohlfahrtiimonas chitiniclastica S5(T). Strain KBL006(T) grew optimally at 30 °C, at pH 8.0 and in the presence of 1-2 % (w/v) NaCl. Oxidase activity and catalase activity were positive. The major fatty acids were C18:1 ω7c, C14:0, and C16:0. The major respiratory quinone was ubiquinone-8 (Q-8). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol, and two phospholipids. The G+C content of the genomic DNA was 45.2 mol%. Based on these polyphasic data, strain KBL006(T) is considered to represent a novel species in the genus Wohlfahrtiimonas, for which the name Wohlfahrtiimonas larvae sp. nov. is proposed. The type strain is KBL006(T) (= KACC 16839(T) = JCM 18424(T)).

Paenalcaligenes hermetiae sp. nov., isolated from the larval gut of Hermetia illucens (Diptera: Stratiomyidae), and emended description of the genus Paenalcaligenes.

A novel Gram-stain-negative, facultatively anaerobic, non-motile and short rod-shaped bacterium, strain KBL009(T), was isolated from the larval gut of Hermetia illucens. Strain KBL009(T) grew optimally at 37 °C, at pH 6.0 and with 1-2 % (w/v) NaCl. The 16S rRNA gene sequence of strain KBL009(T) showed 97.6 % similarity to that of Paenalcaligenes hominis CCUG 53761A(T) indicating its classification with the genus Paenalcaligenes. The major fatty acids were cyclo-C17 : 0, C16 : 0 and summed feature 2 (comprising C14 : 0 3-OH/iso-C16 : 1). The respiratory quinones were ubiquinone-8 (Q-8), predominating, and a minor amount of Q-7. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unknown aminolipid and five unknown polar lipids. The polyamine pattern contained predominantly putrescine and relatively high amounts of spermidine. The betaproteobacterial-specific 2-hydroxyputrescine could only be detected in trace amounts. The G+C content of genomic DNA was 56.1 mol%. Results from DNA-DNA hybridization with P. hominis KCTC 23583(T) unambiguously demonstrated that strain KBL009(T) represents a novel species in the genus Paenalcaligenes. Based on phenotypic, genotypic and phylogenetic characterization, the novel species Paenalcaligenes hermetiae sp. nov. is proposed. The type strain is KBL009(T) ( = KACC 16840(T) = JCM 18423(T)). An emended description of the genus Paenalcaligenes is also provided.

Identification of Heterodera glycines (Tylenchida; Heteroderidae) Using qPCR.

The soybean cyst nematode, Heterodera glycines, is a major plant-parasitic nematode that has caused important economic losses to Korea's soybean production. Four species of cyst nematodes, H. schachtii, H. glycines, H. trifolii, and H. sojae, all belong to schachtii group are coexist in field soil in Korea. The rapid identification of the nematode is crucial for preventing crop damage and in decision making for controlling this nematode. This study aimed to develop a species-specific primer set for quantitative PCR (qPCR) assay of H. glycines. The specific primer set (HGF1 and HGR1) for H. glycines was designed based on the cytochrome c oxidase subunit I (COI) sequence of mitochondrial DNA. After optimization, it is possible to identify the H. glycines using a qPCR assay with DNA extracted from a single cyst and single second-stage juvenile (J2). The specificity was confirmed by the absence of SYBR fluorescent signals of three other Heterodera species. A serial dilution of DNA extracted from a single cyst was obtained for the sensitivity test. The result showed that the standard curve of the test had a highly significant linearity between DNA concentration and Ct value (R 2 = 0.996, slope = -3.49) and that the detection limit concentration of DNA of the primer set was 10 pg of DNA per reaction. Our findings suggested that H. glycines could be distinguished from H. sojae and other Heterodera species when a qPCR assay is used with a specific primer set.

Erratum: Morphological and Molecular Characterization of Heterodera schachtii and the Newly Recorded Cyst Nematode, H. trifolii Associated with Chinese Cabbage in Korea.

[This corrects the article on p. 297 in vol. 34, PMID: 30140183.].

Enhanced biosynthesis of saponins by coronatine in cell suspension culture of Kalopanax septemlobus.

Kalopanax septemlobus is a medicinal woody species of the family Araliaceae, and the pharmaceutical properties of saponins obtained from K. septemlobus suggest that K. septemlobus has the potential to be a crude drug and dietary health supplement. In this study, we established cell suspension culture of K. septemlobus to develop a sustainable source of natura-ceuticals. Friable calli were used for establishing cell suspension culture. The maximum amount of total saponins (1.56 mg/60 ml suspension) was obtained during the 15th day of incubation, whereas the maximum capacity of saponin production was reached after day 6 (0.42 µg/mg of fresh weight). The total saponin production in the cell suspension of K. septemlobus was significantly increased by coronatine (COR) at 160% at a dose of 1 µM compared with the mock-treated control, whereas methyl jasmonate treated cells exhibited less increase in total saponin level as compared to the COR-treated cells. In addition, the elicitation of COR strongly induced the expression of beta-amyrin synthase, thus resulting in the accumulation of oleanolic acid (2.369 ± 0.98 µg/mg of extract), a precursor for oleanane-type triterpene saponins. These results indicate that COR is an efficient elicitor for inducing phytochemicals in cell suspension culture and that it provides the possibility for producing saponins of K. septemlobus using cell suspension culture.

Morphological and Molecular Characterization of Heterodera schachtii and the Newly Recorded Cyst Nematode, H. trifolii Associated with Chinese Cabbage in Korea.

The sugar beet cyst nematode, Heterodera schachtii is a well known pathogen on Chinese cabbage in the highland fields of Korea. However, a race of cyst forming nematode with close morphological resemblance to H. trifolii was recently isolated from the same Chinese cabbage fields. Morphological species differentiation between the two cyst nematodes is challenging, with only minor differences between them. Thus, this study described the newly intercepted H. trifolii population, and reviewed morphological and molecular characteristics conceivably essential in differentiating the two nematode species. A comparison of morphometric measurements of both infective juveniles and vulval cones of cysts showed significant differences between the two cyst nematodes. When total RNA and genomic DNA were extracted from a mixed field population, COI genes and ITS regions were clearly amplified with primers of the two Heterodera species, suggesting that Heterodera population collected from the Chinese cabbage field consisted of a mixture of two species. COI and ITS of H. trifolii were predominantly amplified from nucleotides prepared from H. trifolii monoxenic population whereas those of H. schachtii were strongly detected in H. schachtii monoxenic cultures. Thus, this study confirms the coexistence of the two species in some Chinese cabbage fields; and the presence of H. trifolii in Korea is reported here for the first time.

Plantago lanceolata and Plantago rugelii Extracts are Toxic to Meloidogyne incognita but not to Certain Microbes.

Extracts from the plants Plantago lanceolata and P. rugelii were evaluated for toxicity to the root-knot nematode Meloidogyne incognita, the beneficial microbes Enterobacter cloacae, Pseudomonas fluorescens and Trichoderma virens, and the plant-pathogenic fungi Fusarium oxysporum f. sp. gladioli, Phytophthora capsici, Pythium ultimum, and Rhizoctonia solani. Wild plants were collected, roots were excised from shoots, and the plant parts were dried and ground to a powder. One set of extracts (10% w/v) was prepared in water and another in methanol. Treatments included extract concentrations of 25%, 50%, 75% and 100%, and water controls. Meloidogyne incognita egg hatch was recorded after 7-day exposure to the treatments, and second-stage juvenile (J2) activity after 48 hours. All extracts were toxic to eggs and J2, with P. lanceolata shoot extract tending to have the most activity against M. incognita. Numbers of active J2 remained the same or decreased in a 24-hour water rinse following the 48-hour extract treatment, indicating that the extracts were lethal. When data from water- and methanol-extracted roots and shoots of both plant species were combined for analysis, J2 tended to be more sensitive than eggs to the toxic compounds at lower concentrations, while the higher concentrations (75% and 100%) were equally toxic to both life stages. The effective concentrations causing 50% reduction (EC(50)) in egg hatch and in J2 viability were 44.4% and 43.7%, respectively. No extract was toxic to any of the bacteria or fungi in our assays.

Short-Term Effects of Low-Level Heavy Metal Contamination on Soil Health Analyzed by Nematode Community Structure.

The short-term effects of low-level contamination by heavy metals (As, Cd, Cu, and Pb) on the soil health were examined by analyzing soil nematode community in soils planted with tomatoes. For this, the soils were irrigated with five metal concentrations ([1, 1/4, 1/4(2), 1/4(3), and 0] × maximum concentrations [MC] detected in irrigation waters near abandoned mine sites) for 18 weeks. Heavy metal concentrations were significantly increased in soils irrigated with MC of heavy metals, among which As and Cu exceeded the maximum heavy metal residue contents of soil approved in Korea. In no heavy metal treatment controls, nematode abundances for all trophic groups (except omnivorous-predatory nematodes [OP]) and colonizer-persister (cp) values (except cp-4-5) were significantly increased, and all maturity indices (except maturity index [MI] of plant-parasitic nematodes) and structure index (SI) were significantly decreased, suggesting the soil environments might have been disturbed during 18 weeks of tomato growth. There were no concentration-dependent significant decreases in richness, abundance, or MI for most heavy metals; however, their significant decreases occurred in abundance and richness of OP and cp-4, MI2-5 (excluding cp-1) and SI, indicating disturbed soil ecosystems, at the higher concentrations (MC and MC/4) of Pb that had the most significant negative correlation coefficients for heavy metal concentrations and nematode community among the heavy metals. Therefore, the short-term effects of low-level heavy metal contamination on soil health can be analyzed by nematode community structures before the appearance of plant damages caused by the abiotic agents, heavy metals.

An effective dose assessment technique with NORM added consumer products using skin-point source on computational human phantom.

The aim of this study is to develop the assessment technique of the effective dose by calculating the organ equivalent dose with a Monte Carlo (MC) simulation and a computational human phantom for the naturally occurring radioactive material (NORM) added consumer products. In this study, we suggests the method determining the MC source term based on the skin-point source enabling the convenient and conservative modeling of the various type of the products. To validate the skin-point source method, the organ equivalent doses were compared with that by the product modeling source of the realistic shape for the pillow, waist supporter, sleeping mattress etc. Our results show that according to the source location, the organ equivalent doses were observed as the similar tendency for both source determining methods, however, it was observed that the annual effective dose with the skin-point source was conservative than that with the modeling source with the maximum 3.3 times higher dose. With the assumption of the gamma energy of 1MeV and product activity of 1Bqg-1, the annual effective doses of the pillow, waist supporter and sleeping mattress with skin-point source was 3.09E-16SvBq-1year-1, 1.45E-15SvBq-1year-1, and 2,82E-16SvBq-1year-1, respectively, while the product modeling source showed 9.22E-17SvBq-1year-1, 9.29E-16SvBq-1year-1, and 8.83E-17SvBq-1year-1, respectively. In conclusion, it was demonstrated in this study that the skin-point source method could be employed to efficiently evaluate the annual effective dose due to the usage of the NORM added consumer products.

Citrimicrobium luteum gen. nov., sp. nov., aerobic anoxygenic phototrophic bacterium isolated from the gut of a sea cucumber Stichopus japonicus.

A Gram-stain negative, yellow-pigmented, motile, pleomorphic bacterium, designated strain CBA4602(T), was isolated from the gut of the sea cucumber Stichopus japonicus, which was collected from Jeju Island in the Republic of Korea. In a phylogenetic analysis based on the 16S rRNA gene, strain CBA4602(T) belonged to the order Sphingomonadales in the class Alphaproteobacteria. The 16S rRNA gene sequence similarity between strain CBA4602(T) and 'Citromicrobium bathyomarinum' JF-1, the most closely related strain having nonvalidly published name, was 98.4%, followed by 95.2-96.7% identities with sequence of the other closest strains in the genus Erythrobacter. Strain CBA4602(T) had bacteriochlorophyll a and carotenoids. Strain CBA4602(T) grew in 0-10% (w/v) NaCl, at 10-42°C and pH 6.0-8.0, with optimal growth in 1-2% NaCl, at 30-37°C and pH 7.0. Strain CBA4602(T) was positive for catalase and oxidase activities and was able to hydrolyse gelatine and Tween 20 and 40, but not starch, Tween 80 or L-tyrosine. The G+C content of genomic DNA from strain CBA4602(T) was 68.0 mol% and Q-10 was the major detected isoprenoid quinone. The polar lipids were three unidentified phospholipids, three unidentified glycolipids, and two unidentified lipids. The dominant fatty acids were anteiso-C15:0, C16:0, anteiso-C17:0 and C18:0. As considering the current taxonomic status of the genus 'Citromicrobium' and polyphasic taxonomic analyses, strain CBA4602(T) represents a novel genus and species. The name Citrimicrobium luteum is proposed for the type strain CBA4602(T) (=KACC 17668(T) =JCM 19530(T)).