• The Korean Journal of Ecology
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• v.14 no.1
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• pp.101-111
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• 1991

Amoeba sp. was cultured under the light and the dark conditions, and the activity of phosphatases was investigated. There was a linear correlation between the early reaction time and the activity of phosphatases when phosphatases were incubated at 30℃. Then the activity of acid phosphatase was about 2 times higher than that of alkaline phosphatase. The activity of phosphatase was optimal at pH 5.0 in acidic part and at pH 8.0 in alkaline part, respectively. The optimal temperature of phosphatases was near the 40℃. The isozyme patterns of cytoplasmic acid phosphatase were compared with those of membraneous one. Both the isozyme patterns were shown to bo polymorphic on the polyacyamide gel, but different band patterns were observed in the isozymes of the cytoplasmic and the membraneous acid phosphatases. The number of Amoeba sp. under the light stimulus for 48 hours decreased negative exponentially from the illumination. The activity of acid and alkaline phosphatases under the illumination of light incresed 1.7 and 1.5 times higher, respectively, than the activity of those under the dark condition. This result apperars to be related to the mechanism of the autophosphorylation.

• Journal of Korean Society of Forest Science
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• v.98 no.5
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• pp.531-538
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• 2009

We used enzyme electrophoresis to evaluate genetic diversity in five populations of endemic ash, Fraxinus chiisanensis in Korea. Of 15 putative allozyme loci examined 26.7% were polymorphic and expected heterozygosity for the species was low (0.082). Within the range, population were highly differentiated ($F_{ST}$=0.356) and little genetic variation was explained by geography. The pattern of distribution of variation showed low genetic variation within populations and pronounced divergence among populations, which was consistent with the prediction for the effects of limited gene flow and local genetic erosion. Although the frequencies of male plants were dominant ranging from 79.3% to 89.4%, most mating events seems to be inevitable mating between relatives in small populations based on heterozygote deficiency of this species. Small effective population size and the limited dispersal contributed to the low rates of gene flow within as well as between populations.

• YAKHAK HOEJI
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• v.19 no.4
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• pp.219-226
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• 1975

Physical and chemical properties on the aging inhibition mechanism of hydrous aluminum oxide were studied by means of dehydration velocity, activation energy, DTA, TGA, IR spectra, X-ray diffraction and TMA. During aging, changes may occur in the hydrous aluminum oxide structure which results in a loss of acid reactivity and in crystal formation to the hydrated hydrous alumina. The results obtained from the X-ray diffraction pattern and DTA, TGA thermogram studies showed that the aging product stabilized with either sorbitol or mannitol was hydrous aluminum oxide ($Al_{2}O_{3}{\cdot}xH_{2}O$) but the aging product not stabilized with either sorbitol or mannitol product not stabilized was hydrated hydrous aluminum oxide $Al_{2}O_{3}{\cdot}xH_{2}O{\cdot}yH_{2}O$. The activation energy of dehydration of the hydrous almina was about 17 Kcal. mol$^{1}$ deg$^{-1}$ which was observed a little less than that of 22 kcal.mol.$^{-1}$ deg.$^{-1}$ of or mannitol, the inhibition mechanism in the aging process from oxide is assumed to prevent the formation of the hydrated hydrous aluminum oxide and the aging process is thought of as analogous to the polymorphic transformations which occur as a system converts to its most stable state.

• Genomics & Informatics
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• v.11 no.2
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• pp.93-96
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• 2013

The prediction of externally visible characteristics from DNA has been studied for forensic genetics over the last few years. Externally visible characteristics include hair, skin, and eye color, height, and facial morphology, which have high heritability. Recent studies using genome-wide association analysis have identified genes and variations that correlate with human visible phenotypes and developed phenotype prediction programs. However, most prediction models were constructed and validated based on genotype and phenotype information on Europeans. Therefore, we need to validate prediction models in diverse ethnic populations. In this study, we selected potentially useful variations for forensic science that are associated with hair and eye color, iris pattern, and facial morphology, based on previous studies, and analyzed their frequencies in 1,920 Koreans. Among 20 single nucleotide polymorphisms (SNPs), 10 SNPs were polymorphic, 6 SNPs were very rare (minor allele frequency < 0.005), and 4 SNPs were monomorphic in the Korean population. Even though the usability of these SNPs should be verified by an association study in Koreans, this study provides 10 potential SNP markers for forensic science for externally visible characteristics in the Korean population.

• Korean Journal of Medicinal Crop Science
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• v.21 no.2
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• pp.91-96
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• 2013

This study describes the identification of Panax species using mitochondrial consensus primers. Initially, a total of thirty primers were tested in ten Korean ginseng cultivars and two foreign Panax species, P. quinquefolius and P. notoginseng. In the polymerase chain reaction (PCR) amplification results, three primers (cox1, nad1/2-3 and nad2/1-2) generated co-dominant polymorphic banding patterns discriminating Korean ginseng cultivars from P. quinquefolius and P. notoginseng. However, these primers could not generated polymorphisms among the Korean ginseng cultivars, and simply represented species-specific polymorphisms for P. quinquefolius and P. notoginseng. Primers PQ91 and PN418 were designed from the consensus sequence of nad1/2-3 region. Two banding patterns (A or B) were detected in PQ91. Korean ginseng cultivars and P. notoginseng shared the same banding pattern (A type) and P. quinquefolius was identified another banding pattern (B type). In the case of PN418, two banding patterns (A or B) were detected in the Korean ginseng cultivars and two foreign Panax species. Korean ginseng cultivars and P. quinquefolius shared the same banding pattern (A type) and P. notoginseng was identified another banding pattern (B type). The combination banding patterns of three Panax species, Korean ginseng cultivars (Panax ginseng C. A. Mey.), P. quinquefolius and P. notoginseng, was identified as 'AA', 'BA' and 'AB', respectively. Consequently, PQ91 and PN418 primer sets can be used to distinguish among Panax species.

• Korean Journal of Veterinary Service
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• v.41 no.3
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• pp.149-155
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• 2018

Salmonella Enteritidis (S. Enteritidis) are found in animals, humans, and environment. In addition, S. Enteritidis draws attention to the public health concerns due to carriage of antibiotic resistance traits. For these reasons, the prevalence and antibiotic resistance patterns of S. Enteritidis are significant issues with regard to public health. To address this issues, a total of 24 strains of S. Enteritidis from 164 samples collected from several slaughterhouses in Gyeong-Nam province in order for antibiotic resistance profiles. Subsequently, we characterized the genotyping by random amplification polymorphic DNA (RAPD)-PCR. As a result, very high level of resistance to protein synthesis inhibition antibiotics and most isolates were susceptible to others. Six random primers were used for RAPD-PCR to reveal genotypes of S. Enteritidis isolates. One of the primer, P1245, generated 147 distinct RAPD-PCR fragments ranging from 400~3000 bp. The number of RAPD-PCR products ranged from 4 to 8 for this primer. The RAPD-PCR fragments could be placed these strains into 3 subgroups and 2 classes by UPGMA cluster analysis. Interestingly, several S. Enteritidis that isolated from different slaughterhouses showed same genotype. These results showed only limited genetic variation among the isolates, those were grouped into a few different patterns of antibiotic resistance.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.8
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• pp.993-999
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• 2010

Serum lysozyme gene is one of the important genes influencing the immune system as its product can cause lysis of bacterial cell wall by cleaving the peptidoglycan layer. The present investigation on the serum lysozyme gene of Indian riverine buffalo was undertaken with the objectives to identify and characterize single nucleotide polymorphic patterns by PCR-SSCP method as well as to study the effect of different genotypes on serum lysozyme activity and somatic cell count. A total of 280 animals comprising four different famous bubaline breeds (Murrah, Mehsana, Surti and Bhadawari), spread over six different farms across the country were used for this study. A 276 bp (partial intron 2, complete exon 3 and partial intron 3) fragment of lysozyme gene was screened for polymorphism using the SSCP technique. Four genotypes namely AA, AB, BC and AC were observed, out of which BC genotype was found to be the most frequent. Among these three alleles, C allele (0.38) was most prevalent in these populations. Various SSCP allelic variants were cloned for sequencing and sequences were submitted to NCBI Genbank. From the alignment of the nucleotide sequences of various allelic variants, it was found that there were differences in 12 positions among the alleles, out of which maximum variation (at 8 places) was found in the intronic region. The allele A was closer to allele-C than allele-B. Allele B was phylogenetically equidistant from both of the other alleles. Mean lysozyme activity determined in serum samples of different animals of Murrah buffalo was $27.35{\pm}2.42\;{\mu}g$ per ml of serum, whereas the mean somatic cell count was $1.25{\pm}0.13{\times}10^5$ cells per ml of milk. The SSCP pattern-wise effects of various genotypes on lysozyme activity and SCC were analyzed. Although the mean values were apparently different in various genotypes, these differences were statistically non-significant. It can be concluded that the riverine buffaloes are sufficiently polymorphic with respect to serum lysozyme gene. The absence of AA genotype in Bhadawari breed of buffalo can be considered as a marker for breed characterization. The difference of four nucleotides in exon-3 indicates high selection pressure on the gene.

• Journal of Plant Biotechnology
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• v.45 no.3
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• pp.242-249
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• 2018

This study was conducted to develop an SNP set that can be useful for marker-assisted breeding (MAB) in watermelon (Citrullus. lanatus L) using Genotyping-by-sequencing (GBS) analysis of 20 commercial elite watermelon inbreds. The result of GBS showed that 77% of approximately 1.1 billion raw reads were mapped on the watermelon genome with an average mapping region of about 4,000 Kb, which indicated genome coverage of 2.3%. After the filtering process, a total of 2,670 SNPs with an average depth of 31.57 and the PIC (Polymorphic Information Content) value of 0.1~0.38 for 20 elite inbreds were obtained. Among those SNPs, 55 SNPs (5 SNPs per chromosome that are equally distributed on each chromosome) were selected. For the understanding genetic relationship of 20 elite inbreds, PCA (Principal Component Analysis) was carried out with 55 SNPs, which resulted in the classification of inbreds into 4 groups based on PC1 (52%) and PC2 (11%), thus causing differentiation between the inbreds. A similar classification pattern for PCA was observed from hierarchical clustering analysis. The SNP set developed in this study has the potential for application to cultivar identification, F1 seed purity test, and marker-assisted backcross (MABC) not only for 20 elite inbreds but also for diverse resources for watermelon breeding.

• Korean Journal of Plant Taxonomy
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• v.39 no.1
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• pp.48-54
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• 2009

We investigated the genetic diversity of an endemic rare species, Forsythia ovata Nakai by examining 93 ISSR amplicons in 84 individuals distributed among five populations. The overall percentage of polymorphic ISSR amplicons was 54.8% and mean number of amplicons per ISSR primer was 6.6. The amount of genetic diversity was relatively lower than other shrub species. The Mt. Seokbyeong and Mt. Seorak B populations had the highest level of genetic diversity. Although the Seokgae-jae population had the lowest level of genetic diversity, the population was genetically the most distinctive from the other populations. About 30.6% of the total variation was allocated between five populations, which was slightly higher than other shrub species. Such a pattern of genetic variation may have resulted from the limited distribution and small population sizes of F. ovata. The UPGMA dendrogram based on Nei's genetic distance showed some decisive geographic patterns. These results suggest that, in addition to the preservation of the natural stands, the conservation of larger number of populations with small number of individuals per population is more effective for the dynamic ex situ conservation and for maintaining the genetic diversity of F. ovata than smaller number of populations with large number of individuals.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.757-763
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• 2009

ISSR PCR technique was applied to investigate genetic relationship among 5 Mountain cultivated ginseng populations (Jinan, Hongcheon, Punggi, Andong and Yeongju) and cDNA libraries of wild ginseng roots were constructed and analyzed functional genes related to morphogenesis via EST. Twenty four ISSR markers tested produced 127 polymorphic loci from 5 regional Mountain cultivated ginseng. Among the regional samples, Yeongju was made 18 polymorphic loci that were the highest level of variations among the cultivated regions. The range of similarity coefficient was 0.46~0.58 and the regional samples of Punggi and Hongcheon, Jinan and Andong were classified to similar groups respectively, whereas Yeongju was shown to be separate group with high level of genetic variation in UPGMA cluster analysis. As a result, there was no relationship according to geographical distance and genetic similarity. Eleven cDNA clones were consisted of 9 known genes and 2 unknown genes analyzed by BLAST program of NCBI. To recognize expression pattern of Homeodomain transcription factor related genes, Northern Blot analysis was performed for wild ginseng's leaf and root. As a result, the gene was only expressed by Mountain wild ginseng root.