• Journal of Life Science
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• v.26 no.10
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• pp.1218-1223
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• 2016

Abalones are gastropod mollusks belonging to the genus Haliotis. Fishery products are continuously declining worldwide while abalone production from aquatic farms has considerably increased. Although abalones are regarded as very important marine resources and considered to have big potential in sea-food farming industry around world, the slow growth rate of Pacific abalones is considered to be one of the most serious problems. For the genetic improvements in cultured abalone, advances in various breeding techniques for abalone have been reached through the introduction of selection, crossbreeding, hybridization, and polyploidy in several commercially important abalone species. Six species of abalone have been reported to be distributed along the coasts of Korea: Haliotis discus hannai, Haliotis discus discus, Haliotis madaka, Haliotis gigantea, Haliotis diversicolor diversicolor, and Haliotis diversicolor supertexta. The hybridization between these abalones may be one of the advanced technologies, and the preliminary experiments of interspecific hybrids between abalone species distributed in northern pacific areas including Korea, China, and Japan have been conducted. In this study, we reviewed the phylogenetic relationship of northern pacific abalone species which have the potential traits for aquaculture in Korea and their identifications. We also examined the development of molecular markers and some other aspects of the genetic approaches for successful development of hybrids.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.169-176
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• 2010

A pilot-scale wastewater treatment plant combined with rotating biological contactor and tapered aeration reactors was operated with the wastewater discharged from a food factory for 5 months. The bacterial communities of this plant were investigated by terminal restriction fragment length polymorphism (T-RFLP) and phylogenetic analysis of 16S rRNA genes. In spite of high concentration of nitrogen and phosphorus as well as organic carbon, removal efficiency of chemical oxygen demand, total nitrogen, and total phosphorus was 98%, 93%, and 95%, respectively. Bacterial community at the initial operation stage was clearly distinguished from that of the stable operation stage. The most predominant phylum in the sample of stable stage was Bacteroidetes. Major population of operation period was Haliscomenobacter, Sphaerotilus, and candidate division TM7, which were classified as filamentous bacteria. However, sludge bulking caused by these bacteria was not observed. The population that has a close relationship with Haliscomenobacter increased during the stable operation stage, emerging as the most predominant group. These results suggest that the filamentous bacteria participated in nutrient removal when using rotating biological contactor and tapered aeration reactor.

• Korean Journal of Microbiology
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• v.46 no.3
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• pp.270-277
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• 2010

In order to manufacture Bacillus cereus-free fermented soybean products, an antimicrobial agentproducing isolate against B. cereus was obtained from 150 traditionally fermented soybean products. The morphological and biochemical tests and the phylogenetic relationship among 16S rRNA gene sequences indicated that the isolate named as the strain SCK 121057 was most closely related to Bacillus licheniformis. The B. licheniformis isolate began to produce the antimicrobial agent after 48 h of incubation. The agent was nonproteinaceous and insensitive to heat, long term storage and protease K. Electron microscopic observation indicated that the agent attacked the membrane of B. cereus, leaving the ghost cell. The isolate inhibited growth of B. subtilis, Lactobacillus brevis and various types of pathogenic strains including Escherichia coli, E. faecalis, Micrococcus luteus, Staphylococcus aureus, Aspergillus flavus, A. ochraceus, and A. parasiticus as well as B. cereus. After coinoculation of B. licheniformis SCK 121057 and B. cereus in the ratio (as the basis of CFU/g sample) of 10 to 1 on the surface of cooked soybeans, cell numbers of B. cereus had been dramatically reduced after 31 days of incubation compared to those of single inoculation of B. cereus.

• The Korean Journal of Mycology
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• v.31 no.3
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• pp.121-128
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• 2003

This study was carried out to identify the phylogenetic relationship of Phellinus species and to know its distribution by comparing the DNA sequences of internal transcribed spacer regions(ITS1 and IST2) and 5.8S ribosomal DNA (rDNA) repeat unit. The Phellinus species had their specific sequences in IST1 and 2 regions depending on suedes. The comparison of the ITS sequences of standard strains indicated that the sequences of ITS1 were more variable than those of ITS2. Nine strains of the commercial products of Phellinus species used in this study were identified as P. lintues, P. baumii, P. igniarius, and P. pini. Most of commercial species were P. pini and P. baumii, and P. gilvus was not found. Also, P. linteus was only found in form of mycelial culture rather than fruiting body. Moreover, the species-specific primers were designed based on ITS sequence data. Each species-specific primers were bound in P. lintues(ITSF-PL2R), P. baumii(PB1F-ITS4R), P. igniarius(IF1-IR3), P. pini(PF1-PR3), and P. gilvus(GF2-GR4), respectively. These primer sets would be useful fer the detection of specific-species among unidentified Phellinus species rapidly.

• The Korean Journal of Mycology
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• v.33 no.1
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• pp.1-10
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• 2005

Nineteen strains of Trametes species were collected from the area of Kangwon Province, Korea. They have a variety of color hands and line-up markings on fruit bodies. Most strains were categorized into four types based on color bands, that is, dark brown, light brown, dark gray and light gray. They also have line-up marking shapes from sparse to compact on fruit bodies. In this study, we tried to investigate the relationship between the genetic variation and morphological appearance of these species using the nuclear ribosomal ITS1-5.8S-ITS2 region sequence, we used nineteen strains collected in nature and four species of five standard strains (T. versicolor KCTC16781, KCTC26203, T. villosa KCTC06866, T. suaveolens KCTC26205 and T. hirusta KCTC26200). The data of ITS sequences indicated that nineteen strains of T. versicolor have the difference of $1{\sim}6$ base pairs, comparing with standard strains of T. versicolor KCTC16781, and KCTC26203. Phylogenetic analysis of the Trametes species showed that they grouped into a wide range of single clade. Standard strains except T. versicolor KCTC16781 and KCTC26203, formed separated subgroup.

• Journal of Wetlands Research
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• v.17 no.2
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• pp.139-145
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• 2015

The purpose of this study is to describe and compare the morphological characteristics of seeds of 12 taxa of Araliaceae, and to evaluate their possible use for taxonomic considerations. For light microscope observations and measurements, the seeds were observed using Image Analyzing System. The observations were made on twenty randomly selected seeds of each species. Obtained data were statistically processed using analysis of variance. Principal Components Analysis indicated four groups of characters, the genera Aralia, Eleutherococcus, Panax and the others, which explained 65.47% of the total variation. As a results of Cluster Analysis using the eleven variables, 12 species of Araliaceae were also discriminated into four groups. Eleutherococcus senticosus and E. gracilistylus were closely related, which is well supported by the results from recent molecular studies. Also, the genera Dendropanax and Eleutherococcus were closely related in terms of seed characters.

• Journal of Life Science
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• v.23 no.2
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• pp.182-189
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• 2013

Halophytes are unique land plants that are capable of thriving in a high-salt environment. They are attracting public attention due to their ability to synthesize bioactive substances such as UV protectants or antioxidizing agents. To achieve unaffected growth under high salinity, halophytes may take advantage of the activities of cell growth factors such as expansins. Expansins are well-known cell wall proteins that are responsible for cell enlargement. They loosen cell walls, thereby contributing to actual plant growth. This study aimed to identify positive roles of expansins in the growth of halophytes. Three expansin cDNA clones were isolated from seedlings of Suaeda japonica. Comparing the deduced amino acid sequences of the expansin genes of S. japonica with those of other plant species suggested that the cDNA clones isolated from S. japonica belong to the EXPA (${\alpha}$-expansin) gene family. A phylogenetic tree based on the deduced amino acid sequences revealed that the expansins of S. japonica share a close evolutionary relationship with those of strawberry (Fragaria ananassa) and jujube (Ziziphus jujuba), both of which are woody dicots. SjEXPAs did not show any remarkable change in the gene expression level in different NaCl concentrations, providing a clue to the unaffected seedling growth of S. japonica in a high-salt environment. In conclusion, the present study presents the first report of expansin genes from halophytes and suggests a putative role for these genes in plant growth under high salinity.

• Horticultural Science & Technology
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• v.34 no.1
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• pp.142-153
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• 2016

The present study investigated identification of cultivars through phylogenetic analysis of 108 Citrus varieties and related cultivars using simple sequence repeat (SSR) markers. Two hundred three SSR primer pairs were used to detect polymorphic markers among 8 Citrus cultivars consisting of 4 mandarins, 1 orange, 1 tangor, 1 tangelo, and 1 pumelo. Eighteen SSR primer pairs were reproducible and showed highly polymorphic alleles. These markers were applied to assess genetic variations of the 108 varieties. Each marker detected 5-14 alleles, with an average of 9.28. The polymorphism information content varied from 0.417 to 0.791 with an average of 0.706. Cluster analysis with SSR markers resulted in 13 major groups reflecting cultivar types and pedigree information. Twelve orange cultivars in the $I-1^{st}$ sub-cluster and 23 mandarin cultivars in the $II-1^{st}$ sub-cluster, respectively, were not discriminated using the SSR markers. This could be due to narrow genetic backgrounds originated through bud mutation or nucellars seedlings. The SSR profile database of Citrus cultivars will be useful as a tool for protection of plant breeders' intellectual property rights in addition to assessing genetic diversity in Citrus cultivars and germplasms.

• Korean Journal of Plant Taxonomy
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• v.39 no.3
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• pp.135-142
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• 2009

Phylogeny of the family Ophioglossaceae and a phylogenetic position of Mankyua were estimated through analyses of chloroplast rbcL gene sequences and spore morphology. Sequence analysis of the rbcL gene clearly indicated that there are two major lineages in the family Ophioglossaceae: Botrychioid lineage and Ophioglossoid lineage. The Botrichioid lineage is composed of three distinct clades: Botrychium, Helminthostachys and Mankyua, where Helminthostachys and Mankyua were placed as sister groups to the Botrychium. Within the genus Botrychium, subgenera Septridium and Botrychium were monophyletic, while taxa of subgen. Botrypus branched as sister of the two, successively, thus making a non-monophyletic group. Ophioglossum formed the Ophioglossoied lineage, where the subgen. Ophioglossum is monophyletic, while subgen. Cheiroglossa and Ophoderma formed a sister relationship with subgen. Ophioglossum. In terms of external morphology and spores, Mankyua is most similar to Helminthostachys, however, patristic distance in the cladogram and trophophore characteristics of the two genera are distinct. Therefore, Mankyua is a well defined genus within the family in terms of morphology as well as molecular phylogeny which places it in basal position of the Botrychioid lineage on the gene tree.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.333-341
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• 2021

In this study, to select strains suitable as microbial agent from among rhizosphere microorganisms present in rhizosphere soil and roots, the mineral solubilization ability, antifungal activity against 10 types of plant pathogenic fungi, and plant growth-promoting activity of rhizosphere microorganisms were evaluated. As a result, DDP346 was selected because it has solubilization ability of phosphoric acid, calcium carbonate, silicon, and zinc; nitrogen fixing ability; production ability of siderophore, indole-3-acetic acid, and aminocyclopropane-1-carboxylate deaminase; and antifungal activity against seven types of plant pathogenic fungi. DDP346 showed a 99.9% homology with Acinetobacter pittii DSM 21653 (NR_117621.1); phylogenetic analysis also revealed a close relationship with Acinetobacter pittii based on the 16S rRNA base sequence. The growth conditions of DDP346 were identified as temperatures in the range of 10-40 ℃, pH in the range of 5-11, and salt concentrations in the range of 0-5%. In addition, a negative correlation coefficient (r² = -0.913, p <0.01) was shown between pH change and the solubilized phosphoric acid content of Acinetobacter sp. DDP346, and this is assumed to be due to the organic acid generated during culture. Consequently, through the evaluation of its mineral solubilization ability, antifungal activity against plant pathogenic fungi, and plant growth-promoting activity, the potential for the utilization of Acinetobacter sp. DDP346 as a multi-purpose microbial agent is presented.