• Korean Journal of Medicinal Crop Science
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• v.16 no.3
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• pp.195-198
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• 2008

Karyotypic analysis and FISH (fluorescence in situ hybridization) with 45S and 5S rRNA genes were carried out in Persicaria tinctoria H Gross. The somatic metaphase chromosomes were ranged from 2.25 ${\mu}m$ to 1.50 ${\mu}m$ in length. Chromosome number was 2n = 4x = 40 with the basic number of x = 10. The chromosome complement of the species consisted of 16 pairs of metacentrics (chromososomes 1,2,3,4,6,7,8,9, 10, 11, 12, 13, 15, 18, 19 and 20) and 4 pairs of submetacentrics (chromosome 5, 14, 16 and 17). The karyotype formula was K(2n) = 4x = 32 m + 8 sm. In FISH analysis, three pairs of 45S rRNA gene loci on the terminal region of submetacentrics (chromosomes 5, 16 and 17) and two pairs of 5S rRNA gene loci on the centromeric region of metacentrics (chromosomes 9 and 11) were detected, respectively.

• Journal of fish pathology
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• v.26 no.2
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• pp.77-88
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• 2013

Starry flounder, Platichthys stellatus (body length $4.4{\pm}0.51cm$) that became sick during an outbreak of disease at mariculture facilities at Ulsan, Korea in August of 2012, were examined to identify the cause of the disease. Diseased fish didn't show a unique sign, but the oxidase-positive and gram negative rod was isolated from moribund fish. The bacterium was revealed as Photobacterium damselae subsp. piscicida by biochemical analysis and sequence analysis of the 16S rRNA and capsular polysaccharide (CPS) genes. The isolates (AD5) was carrying susceptible to ofloxacin and gentamycin and showed high growth value at $18^{\circ}C$ and $25^{\circ}C$ compared to four other P. damsela strains.

• Korean Journal of Microbiology
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• v.39 no.3
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• pp.192-196
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• 2003

To obtain large pools of lactic acid bacteria, a strain was isolated from Tongchimi. Through its sugar fermentation and analysis of 16S rRNA gene, it was identified to be Lactobacillus plantarum HB1. This strain is Gram-positive and catalase-negative. In the range of 1～88 bp in the HB1 16S rRNA gene, the HB1 strain was homologous with other L. plantarum strains by almost 100%, and in the range of the rest 32 bp, the HB1 strain showed considerable variation, compared to other strains. Nitrate which may exist in radish can be easily converted to nitrite. The nitrite interacts with amine, and becomes nitrosamine which may cause stomach cancer. The culture obtained by HB1 strain could eliminate 400 ${\mu}M$ nitrite within 1.5 hr. It is necessary to isolate specific components which are involved in nitrite elimination in the culture and to study on its mechanism.

• Journal of Life Science
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• v.24 no.4
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• pp.361-369
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• 2014

Broad-range and specific 16S rRNA gene PCR is used for detection and identification of bacterial pathogens in clinical specimens from patients with a high suspicion for infection. We describe the development of a broad-range and specific PCR primer, based on bacterial 16S rRNA, for use in routine diagnostic clinical microbiology services. The primers were designed by using conservative regions of 16S rRNA sequences from 10 strains. Ninety-eight clinical strains were isolated from clinical patient specimens. A total of 98 strains of bacteria were identified by phenotypic methods; PCR with newly designed primers and universal primers. All purified PCR products were sequenced using both forward and reverse primers on an automated DNA analyzer. In this study, we evaluated the usefulness of the newly designed primers and the universal primers for the detection of bacteria, and both these techniques were compared with phenotypic methods for bacteria detection. When we also tested 98 strains of clinical isolates with newly designed primers, about 778 bp DNA fragments were amplified and identified from all strains. Of the 98 strains, 94 strains (95.9%) correspond in comparison with phenotypic methods. The newly designed primers showed that the identities of 98 (100%) strains were the same as those obtained by universal PCR primers. The overall agreement between the newly designed primers and universal primers was 100%. The primer set was designed for rapid, accurate, and cheap identification of bacterial pathogens. We think the newly designed primer set is useful for the identification of pathogenic bacteria.

• Korean Journal of Microbiology
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• v.54 no.1
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• pp.81-83
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• 2018

We sequenced the genome of the Neisseria sp. KEM232 isolated from the smooth surface caries of human cavity of a 7-year old male in Republic of Korea by using the standard dilution plating technique. The genome comprises a single circular 2,371,912 bp chromosome with a G + C content of 58.5%, 2,210 protein-coding genes, 108 pseudo genes, 51 RNA genes, and one CRISPR array. Based on the 16S rRNA gene sequence similarity and average nucleotide identity, the strain KEM232 is most closely related to Neisseria baciliformis.

• Research in Plant Disease
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• v.17 no.3
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• pp.265-271
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• 2011

Seven phytoplasma diseases have been occurred on floricultural crops in Korea : Ph-ch1 and Ph-ch2 of chrysanthemum, Ph-lily of lily, petunia flat stem-Korean (PFS-K) of petunia, poinsettia branch inducing- Korean (PoiBI-K) of poinsettia, statis witches' broom-Korean (SWB-K) of statis and azalea witches broom (AWB). Classification of the seven phytoplasmal diseases based on 16S ribosomal RNA (rRNA) sequences showed that floricultural crop phytoplasma disease were widespread in order of aster yellow (AY), stolbur and X-disease in Korea. In phenotypic characters, the fasciation was occurred in both monocotyledon plant of lily and dicotyledon plants of petunia and poinsettia. Besides, the fascination was occurred in Ph-lily of stolbur, petunia PFS-K of AY and PoiBI-K of X-disease. This result indicated that phytoplasma classification based on 16S rRNA and symptoms are not consistently related. The comparison of 16S rRNA sequence of the seven floricultural crop phytoplasma with five tree phytoplasmal diseases of jujube witches' broom, paulownia witches' broom, wild jujube witches' broom, mulberry dwarf, golden rain phytoplasma occurred in Korea showed as high as 88.5-99.9% homology. Among them, especially mulberry dwarf showed the highest homology with the seven floricultural crop phytoplasms. Based on this result, floricultural crop phytoplasmas were assumed to be transmitted by insect vectors from tree phytoplasmas in Korea.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.148-155
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• 2015

The diversity of endobacteria in the edible part (cap and stipe) king oyster mushroom (Pleurotus eryngii) was investigated using 16S rRNA sequence analysis. The bacterial 16S rRNA libraries were constructed from the body cap (BC) and the body stipe (BS) of the king oyster mushroom. The twenty sequenced BC clones were divided into four groups and the largest group was affiliated with the Firmicutes (40% of clones). While, the twenty sequenced BS clones could be divided into six groups and the largest group was affiliated with the Actinobacteria (40% of clones). The predominant bacterial family from both the cap and stipe of the mushroom was corresponded with the Gram positive bacteria (62.5%).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.2
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• pp.103-109
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• 2000

Complete senuences of the mitochondrial rRNA Benes were determined among six salmonines in Korean Waters (Brachpmystax lenok, Onoorhpchus keta, O. masou mason, O. mason ishikawae, O. mykiss, and albino mutant of O. mykiss). The purposes of this study were to provide the basic information on levels of mtDNA polymorphism among these species for genetic characterization; discuss phylogentic relationships among three Oncorhynchus sepecies; demonstrate the utility of rRNA gene sequence data as a genetic marker for disringuishinf among Korean salmonines. PCR/direct sequencing data indicated the following consistent results; 1) 12S rRNA genes was 945 bases long in Oncorhynchus species, and 946 bases in B. lenot including one insertion. 2) Of sequence variation in mitochondrial rRNA regions, transitional substitutions were superior to transversion. 3) The significant differences were not shown in the intraspecific variation values in these gene regions. The percentage sequence divergence values were ranged from $0.066 to 0.212{\%}$. 4) The interspecific divergences were greater than the intraspecific variation. Nevertheless, ribosomal RMh genes were more conserved among species than the other mitochondrial genes, and they showed potentiality as an intergenic marker for systematics. In addition, phylogenetic trees, constructed from this data, supported that cherry salmon was closer to chum salmon than to rainbow trout, and that lenok was most distantly related species in six salmonid species.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.220-225
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• 2019

Studies based on microbial community analyses have increased in the recent decade since the development of next generation sequencing technology. Associations of gut microbiota with host's health are one of the major outcomes of microbial ecology filed. The major approach for microbial community analysis includes the sequencing of variable regions of 16S rRNA genes, which does not provide the information of bacterial activities. Here, we conducted RNA-based microbial community analysis and compared results obtained from DNA- and its cDNA-based microbial community analyses. Our results indicated that these two approaches differed in the ratio of Firmicutes and Bacteroidetes, known as an obesity indicator, as well as abundance of some key bacteria in gut metabolisms such as butyrate producers and probiotics strains. Therefore, cDNA-based microbial community may provide different insights regarding roles of gut microbiota compared to the previous studies where DNA-based microbial community analyses were performed.

• Journal of Korean society of Dental Hygiene
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• v.13 no.5
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• pp.889-900
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• 2013

Objectives : Molecular biology techniques were employed to assess diversity of bacterial in children's dental caries. Methods : DNA of germs was extracted and the diversity of the 16S rRNA clones was analyzed by amplified rDNA restriction analysis and sequencing. The experimental samples were pit and fissure caries (PC), deep dentinal caries (DC), smooth surface caries (SC), and supragingival plaque (PQ) from 50 children of age less than 12 years old. The control group was healthy teeth supragingival plaque (HT). Thirty clones from each 16S rRNA clone library of 5 samples were randomly selected, thus a total of 150 clones were analyzed. Results : Amplified rDNA restriction analysis uncovered 18, 20, 11, 17, and 22 phylotypes from healthy teeth, pit and fissure caries, deep dentinal caries, smooth surface caries, and supragingival plaque, respectively. Sequencing analysis found the dominance of Actinomycs naeslundii and Fusobacterium nucleatum in the healthy teeth; Leptotrichia sp. in the pit and fissure caries; Actinomyces sp., Streptococcus mutans, and Rahnella aquatilis in the deep dentinal caries; Streptococcus mutans and Actinomyces sp. in the smooth surface caries; Enterobacter hormaechei and Streptococcus sanguinis in the supragingival plaque. Conclusions : Clonal analysis identified 6 phyla, 20 genera, and 51 species.