• Animal Systematics, Evolution and Diversity
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• v.16 no.2
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• pp.203-211
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• 2000

Partial mitochondrial 16S rDNA and COI gene were amplified using PCR and sequenced for four species of oysters in Korea. Phylogenetic relationships among them were inferred from their aligned sequences by neighbor-joining method. The sequence comparison data of two mitochondrial genes showed that the genetic distinction between two oyster genera (Crassostreo and Ostrea) was obvious. Phylogenetic analysis based on the nucleotide sequences and A+T percentage of two genes indicates that C. gigas and C. nippona strongly formed a sister group and then C. ariakensis was clustered with the clade although that based on amino acid sequences of COI gene by neighbor-joining method represented different phylogenetic tree.

• Korean Journal of Microbiology
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• v.46 no.4
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• pp.405-408
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• 2010

Diversity of myxobacteria in five soil samples from Asansi and Uponeup in Korea was explored by means of polymerase chain reaction (PCR) using primers that specifically bind 16S rDNA of myxobacteria. DNA sequence analysis of 76 PCR fragments containing myxobacterial 16S rDNA revealed five putative novel myxobacterial genera whose 16S rDNA sequences shared <95% sequence identity with those of the type strains. This finding indicates the presence of many uncultured and unidentified myxobacterial species in Korean soil.

• Research in Plant Disease
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• v.9 no.4
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• pp.189-195
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• 2003

Bacteria causing fermentation in Oriental melon were identified as three independent groups on the basis of 16S rDNA sequence analysis. The 16S rDNA sequence of the strain CM2105 showed the highest identity (99.6%) with that of Microbacterium phyllosphaerae, and also indicated high sequence identity to that of M. holiorum (99.5%). The 16S rDNA sequences of the strain CM2101 and CM2121 matched at the high sequence similarity (98.9%, 98.8, respectively), to that of Pseudomonas pavonacea, and the DNA sequence of CM2126 showed high sequence identity to that of P. costantinii (99.5%), and P. grimontii (99.0%). The 16S rDNA sequence of the strain CM2113 showed the highest identity (99.7%) with that of Enterobacter cloacae. The 16S rDNA sequences, the physiological and biochemical analysis suggested that the strain CM2105 belonged to Microbacterium phyllosphaerae, CM2101, CM2121 and CM2126 to Pseudomonas spp., CM2113 to Enterobacter cloacae.

• The Korean Journal of Ecology
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• v.22 no.1
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• pp.45-50
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• 1999

A bacteriocin-producing strain was isolated from kimchi at the early stage of kimchi fermentation. It was identified as Lactococcus lactis by morphological, cultural and physiological characteristics and partial sequence of 16S rDNA. The bacteriocin from isolate had antimicrobial activity against gram positive pathogenic bacteria, such as Listeria monocytogenes. Staphylococcus aureus and several strains of lactic acid bacteria but not to gram negative bacteria, Yersinia enterocolitica. The bacteriocin was sensitive to protease, protease ⅩⅣ, a-chymotrypsin and pepsin but not to lipase, trypsin and lysozyme. The bacteriocin activity was stable at pH 2-11 and temperature of 100 for 10 min. Thus, Listeria monocytogenes could be inhibited by Lactococcus lactis at early stage of fermentation.

• Animal Systematics, Evolution and Diversity
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• v.36 no.4
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• pp.382-386
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• 2020

In this study, Prionospio depauperata Imajima, 1990 is newly reported in Korean fauna. Prionospio depauperata can be distinguished from other relatives by the four pairs of branchiae which are pinnate on chaetigers 2 and 5, and apinnate on chaetigers 3 and 4; caruncle extending to the end of chaetiger 2; and moderate dorsal crest present on chaetigers 7-13. The morphological diagnosis of P. depauperata are provided with the photographs of four Prionospio species. The mitochondrial cytochrome c oxidase subunit 1 (CO1), 16S ribosomal DNA (16S rDNA), and the nuclear 18S ribosomal DNA (18S rDNA) sequences of four Prionospio species from Korean waters, P. depauperata Imajima, 1990, P. japonica Okuda, 1935, P. krusadensis Fauvel, 1929, and P. membranacea Imajima, 1990, were determined for the first time. The inter-specific genetic distances among the congeners of four Prionospio species were 22.3-29.6% in CO1, 10.5-25.0% in 16S rDNA, and 0.3-3.6% in 18S rDNA.

• Animal Systematics, Evolution and Diversity
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• v.37 no.4
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• pp.349-353
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• 2021

Scolelepis (Parascolelepis) papillosa (Okuda, 1937), originally described from a single incomplete individual from Jeju Island in Korea, was collected from the intertidal sandflats of Soan Island (Jeollanam-do province) in Korea. The examined specimens of S. (P.) papillosa agree well with the original description in having the papillae on the basal sheath of the palps, presence of occipital antenna, absence of notochaetae in chaetiger 1, branchiae completely fused with notopodial postchaetal lamellae at the anterior chaetigers, and neuropodial hooded hooks appearing from chaetiger 16. In this study, the sequences of partial mitochondrial cytochrome c oxidase subunit I (COI), 16S ribosomal DNA (16S rDNA), and the nuclear 18S ribosomal DNA (18S rDNA) of the species were determined. We also provide the detailed description and illustrations on this species based on the complete specimens newly collected in this study.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.170-176
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• 2009

Culture-independent 16S rDNA-DGGE profiling and phylogenetic analysis were used to examine the predominant bacterial communities associated with the two sponges, Dictyonella sp. and Spirastrella abata from Jeju island. The culture-independent approach involved extraction of total bacterial DNA, PCR amplification of the 16S ribosomal DNA using primer pair 341f-GC and 518r, and separation of the amplicons on a denaturing gradient gel. Denaturing gradient gel electrophoresis banding patterns indicated 8 and 7 bands from the two sponge species, Dictyonella sp. and Spirastrella abata, respectively. There were not common major bands in two different sponges. Comparative sequence analysis of variable DGGE bands revealed from 93% to 98% similarity to the known published sequences. The dominant bacterial group of Dictyonella sp. belonged to uncultured Gammaproteobacteria, while, that of Spirastrella abata belonged to uncultured Alphaproeobacteria and Firmicutes. DGGE analysis indicated predominant communities of the sponge-associated bacteria differ in the two sponges from the same geographical location. This result revealed that bacterial community profiles of the sponges were host species-specific.

• Korean Journal of Microbiology
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• v.37 no.2
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• pp.137-144
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• 2001

In order to investigate the diversity of bacterial community in the mud flat of Sunchon Bay, Chunnam province, diversity of amplified 16S rDNA was examined. Total DNA was extracted from sediment soils and 16S rDNAs were amplified using PCR primers based on the universally conserved sequences in bacteria. Clonal libraries were constructed and 111 clones were examined by amplified rDNA restriction analysis (ARDRA) using HaeIII. Clones were clustered based on restriction patterns using computer program, GelCompar II. One hundred different RFLP types were detected from 111 clones. The 20 clones were selected and sequenced according to dendrograms derived from ARDRA, to cover most of the bacterial diversity in the clone libraries. None of the clones were identical to any representatives in the Ribosomal Database Project small subunit RNA databases and GenBank. All sequences showed between 77 and 96.8% similarity to the known 16s rRNA sequence from cultured organisms. The 20 clones sequenced fell into seven major lineages of the domain Bacteria: alpha-, delta-, gamma-Proteobacteria, low G+C Gram positive bacteria, high G+C Gram positive bacteria, Sphingobacteria (Cytophaga) and Cyanobacteria (chloroplast). Among the clones, the Proteobacteria were dominant.

• Korean Journal of Microbiology
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• v.39 no.3
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• pp.187-191
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• 2003

In an attempt to isolate myxobacteria from soil samples, we isolated swarm and fruiting body forming bacteria that have bacteriolytic activity on Coli-spot agar plate. For the classification of myxobacteria, 16S rDNA RFLP patterns were analyzed. Amplified 16S rDNAs of myxobacteria type strains (Family I, II, III and IV), negative control strains and soil-isolates were restricted with HaeIII, EcoRI and EcoRV, respectively. We found that the soil-isolates belongs to myxobacteria Family I, II, III.

• Journal of Microbiology and Biotechnology
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• v.24 no.6
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• pp.812-822
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• 2014

Metagenomic analysis of the human intestinal microbiota has extended our understanding of the role of these bacteria in improving human intestinal health; however, a number of reports have shown that current total fecal DNA extraction methods and 16S rRNA universal primer sets could affect the species coverage and resolution of these analyses. Here, we improved the extraction method for total DNA from human fecal samples by optimization of the lysis buffer, boiling time (10 min), and bead-beating time (0 min). In addition, we developed a new long-range 16S rRNA universal PCR primer set targeting the V6 to V9 regions with a 580 bp DNA product length. This new 16S rRNA primer set was evaluated by comparison with two previously developed 16S rRNA universal primer sets and showed high species coverage and resolution. The optimized total fecal DNA extraction method and newly designed long-range 16S rRNA universal primer set will be useful for the highly accurate metagenomic analysis of adult and infant intestinal microbiota with minimization of any bias.