Siwon Lee

Detection of Carnation necrotic fleck virus and Carnation ringspot virus Using RT-PCR

Carnation is considered to be one of the top three cutting flowers in the world, which is a main crop with 21 billion annual volume of manufacture. The four carnation items such as cuttings, seed, plant and unrooted cuttings are imported and exported. Viruses can be easily transmitted during vegetative propagation of carnation. Carnation necrotic fleck virus (CNFV) and Carnation ringspot virus (CRSV) are designated as Korea plant quarantine viruses and inspected. This study was aimed to develop specific primer sets for easy and rapid detection of CNFV and CRSV. Two RT-PCR primer sets were efficiently amplified 288 and 447 bp fragments for CNFV and 503 549 bp fragments for CRSV. Furthermore, developed nested primer sets make possible to high sensitive detection and verification. CNFV nested PCR primer sets all produced band of 147 bp and CRSV nested PCR primer sets did bands of 395 and 347 bp. In addition, plasmid inserted 6 sequences in amplicon were used as a positive control to improve inspection confidence. The successful application of PCR module newly developed in this study will be highly useful for detect of CNFV and CRSV for quarantine inspections.

Development of RT-PCR and Nested PCR for Detecting Four Quarantine Plant Viruses Belonging to Nepovirus

For quarantine purpose, we developed the RT- and nested PCR module of Tomato black ring virus (TBRV), Arabis mosaic virus (ArMV), Cherry leafroll virus (CLRV) and Grapevine fanleaf virus (GFLV). The PCR modules, developed in this study make diagnosis more convenient and speedy because of same PCR condition. And also, the methods are more accurate because it can check whether the result is contamination or not using the mutation-positive control. We discard or return the 27 cases of Nepovirus infection seed by employing the module past 3 years. This study provides a rapid and useful method for detection of four quarantine plant viruses.

Flavihumibacter cheonanensis sp. nov., isolated from sediment of a shallow stream.

A Gram-reaction-positive, rod-shaped, strictly aerobic and non-motile bacterial strain, designated WS16(T), was isolated from the sediment of a shallow stream located in Cheonan, Korea. The strain grew optimally at 28 °C, at pH 7.0 and in the absence of NaCl. Phylogenetic trees based on 16S rRNA gene sequences suggested that the isolate belonged to the genus Flavihumibacter of the phylum Bacteroidetes. Comparative 16S rRNA gene sequence analysis showed that strain WS16(T) was related most closely to Flavihumibacter petaseus T41(T) (96.8 % similarity). The isolate contained MK-7 as the predominant menaquinone and iso-C15 : 0, iso-C15 : 1 and iso-C17 : 0 3-OH as the major fatty acids. The genomic DNA G+C content of the isolate was 45.9 mol%. The results of a polyphasic taxonomic approach indicated that strain WS16(T) represents a novel species of the genus Flavihumibacter, for which the name Flavihumibacter cheonanensis sp. nov. is proposed. The type strain is WS16(T) ( = KACC 17467(T) = JCM 19322(T)).

Emticicia sediminis sp. nov. isolated from sediment of a shallow stream

A novel bacterial strain, designated JBR12T, was isolated from sediment of a shallow stream in Cheonan, Korea. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain JBR12T belongs to the genus Emticicia, and indicated that its closest relatives are Emticicia oligotrophica DSM 17448T (97.8 % sequence similarity) and E. ginsengisoli Gsoil 085T (94.3%). A DNA-DNA hybridization experiment revealed < 70 % genomic relatedness between strain JBR12T and E. oligotrophica DSM 17448T. The major fatty acids (>5% of the total) were iso-C15 : 0, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), iso-C15 : 0 3-OH, anteiso-C15 : 0 and iso-C15 : 0 3-OH. The DNA G+C content of strain JBR12T was 37.7 mol%. According to data from the present polyphasic taxonomic study, strain JBR12T represents a novel species of the genus Emticicia, for which the name Emticicia sediminis sp. nov. is proposed. The type strain is JBR12T ( = KACC 17466T = JCM 19321T).

Development of rapid and highly sensitive detection of Bean common mosaic necrosis virus in leguminous crops using loop-mediated isothermal amplification assay

Bean common mosaic necrosis virus (BCMNV) is a plant pathogenic virus that can infect leguminous crops such as kidney beans, sunn hemp, red beans, and mung beans. BCMNV has not been reported in Korea and is classified as a quarantine plant virus. Currently, the standard diagnostic method for diagnosis of BCMNV is reverse transcription (RT)-nested PCR system. However a more rapid monitoring system is needed to enable the testing of more samples. The use of highly efficient loop-mediated isothermal amplification (LAMP) assay for its detection has not yet been reported, and development of LAMP for detecting BCMNV in this study. In addition, confirmation of LAMP amplification can be achieved using restriction enzyme Mse I (T/TAA). The developed technique could be used for more rapid, specific and sensitive monitoring of BCMNV in leguminous crops than conventional nested RT-PCR.

Bacillus daqingensis sp. nov. isolated from near poultry farm soil

A novel bacterial strain, designated PFS-5T, was isolated from the soil environment with feces of a live poultry farm located in Cheonan, Republic of Korea. Strain PFS-5T was Gram-staining-positive, motile, strictly aerobic bacterium, rod-shaped, and endospore-forming. The strain contained meso-diaminopimelic acid in their peptidoglycan and MK-7 menaquinone. The major fatty acids were anteiso-C15:0 (44.2%), C16:0 (22.2%), and iso-C15:0 (16.7%). The DNA G+C content was 40.1 mol%. Comparative 16S rRNA gene sequence analysis identified strain PFS-5T in the genus Bacillus, exhibiting the highest level of sequence similarity with type strain of B. herbersteinensis D-1,5aT (96.9%), B. humi LMG 22167T (96.7%), B. alkalitelluris BA288T (96.1%), B. litoralis SW-211T (96.0%), and B. luteolus YIM93174T (95.5%). The major polar lipids of PFS-5T were diphosphatidylglycerol and phosphatidylglycerol. On the basis of result from poly-phasic data, strain PFS-5T represents a novel species, for which the name Bacillus cheonanensis sp. nov. is proposed (Type strai PFS-5T = KACC 17469T = JCM19333T).

Nocardioides suum sp. nov. isolated from the air environment in an indoor pig farm

A bacterial strain PBT33-2T was isolated from the air environment in an indoor pig farm. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain PBT33-2T belonged to the genus Nocardioides in the phylum Actinobacteria, and was most closely related to Nocardioides daphnia D287T in a maximum-likelihood and neighbor-joining phylogenetic trees. Strain PBT33-2T shared 95.3% sequence identity with N. daphnia D287T. However, the highest sequence similarity was shown with N. sediminis MSL-01T (96.0%). It had less than 96.0% sequence identities with other type species of the genus Nocardioides. Strain PBT-33-2T grew at 15–45°C (optimum 20–35°C), pH 5.0–11.0 (optimum pH 7.0) and 0–4.0% (w/v) NaCl (optimum 0%). The major fatty acid and quinone were iso-C16:0 and MK-8, and the DNA G+C content of strain PBT33-2T was 69.3 mol%. On the basis of poly-phasic results, strain PBT33-2T represents a novel species of the genus Nocardioides, for which the name Nocardioides suum sp. nov. is proposed. Its type strain is PBT33-2T (=KCTC 39558T =DSM 102833T).

Characterization of Culturable Bacteria in the Atmospheric Environment in Incheon, Korea

Objectives: This study aims to provide basic data regarding the bacterial total plate count in the atmospheric environment for related studies. Methods: Total plate count and the identification of culturable bacteria in the atmospheric environment in Incheon took place in 2015 using periodic survey. Correlationship analysis was performed between the number of culturable bacteria and environmental elements. In addition, an estimation of novel bacterial species was undertaken using the similarities and phylogenetic tree based on the 16S rRNA gene. Results: The total plate count of culturable bacteria was on average 176 CFU/m, and did not exceed 610 CFU/m in the atmospheric environment. Periodic monthly measuring of total plate count was highest in June at 293 CFU/m, while the lowest was in July at 125 CFU/m. Furthermore, as a result of the identification of culturable bacteria, the genera Arthrobacter and Kocuria were dominant, while novel bacterial taxa that belong to the genera Chryseobacterium and Herbiconiux were separated. Conclusion: The total number of culturable bacteria from the atmospheric environment in Korea is on average 176 CFU/m. In addition, the genera Arthrobacter and Kocuria dominate. The presence of novel bacterial taxa are expected in the atmospheric environment, such as belonging to the genera Chryseobacterium and Herbiconiux.

Erratum to: Bacillus cheonanensis sp. nov. isolated from near poultry farm soil

Despite the correct article title in the article PDF, due to Publishers error during the process of online publication, the title of the article appears incorrectly in the article webpage. The correct title is shown here and a well as in the article PDF. The Publisher deeply apologizes for this mistake.