• Korean Journal of Microbiology
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• v.49 no.4
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• pp.377-382
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• 2013

The bacterial community structures of the marine sponge, Dactylospongia metachromia, collected from Chuuk of Micronesia on February 2012, were analyzed by denaturing gradient gel electrophoresis (DGGE). The DGGE fingerprints of two individuals of D. metachromia, CH607 and CH840 showed the same band patterns. The sequences derived from DGGE bands revealed 93~100% similarities with known bacterial species in the public database and high similarity with uncultured bacterial clones. The bacterial community structures of both D. metachromia sponges (CH607, CH840) were composed of 6 phyla, 8 classes: Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, Cyanobacteria, Spirochaetes. DGGE fingerprint - based phylogenetic analysis revealed that the bacterial community profiles were identical in two individuals of the same sponge species collected from the same geographical location.

• The Plant Pathology Journal
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• v.17 no.5
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• pp.281-289
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• 2001

We analyzed 88 strains of Gibberella fujikuroi (Analmorph: Fusarium section Liseola) from maize in Korea for mating population, mating type, fumonisin production vegetative compatibility, and random amplified polymorphic DNA (RAPD) patterns. We found 50 strains that were MATA-2, 22 that were MATA-1, 1 that was MATD-1, and 15 that were not reproducibly fertile with any of the mating type testers. Of the 50 MATA-2, 15 were female fertile, while 10 of the 22 MATA-1 strains were female fertile. A total of 1,138 nitrate non-utilizing (nit) mutants were recovered from a total of 88 strains. These strains were grouped into 39 vegetative compatability groups (VCGs) by demonstrating heterokaryosis between nit mutants. A single maize ear could be infected by more than one VCG of F. moniliforme. RAPD analysis measured genetic diversity among 63 strains of F. moniliforme. Several VCGs were distinguished by RAPD fingerprinting patterns. Most strains produced significant levels of fumonisins. However, 6 MATA-2 strains from a single VCG produced higher levels of fumonisin $\textrm{B}_3$ than that of fumonisin $\textrm{B}_1$ or $\textrm{B}_2$. From these data, we concluded that most Korean strains of F. moniliforme associated with maize belonged to mating population A and produced significant levels of fumonisins. Futhermore, RAPD analysis could differentiate strains associated with different VCGs.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.85-85
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• 2017

Potato is important carbohydrate source over the world in that revealing high productivity per the unit area, and their cultivation area is estimated to be increased to cope with a scarcity of food according to the population increase. Major cultivated species of potato is Solanum tuberosum (2n = 4x = 48) and regarded as being originated in Andes region of South America. The diverse potato genetic resources has been collected and perserved in Highland Agricultural Research Institute (NICS, RDA), and the genetic materials as DNA stock is conserved in National Agrobiodiversity Center(NAS, RDA). The understanding of genetic constitution of conserved diversity is the basis for the germplam management and further utilization. In this study, we analyzed the genetic diversity of potato germplasm(479 accessions) using 24 microsatellite markers which have been internationally used for fingerprinting of potato accession. The allele number and polymorphic information content (PIC) of total accessions per locus was ranged from 2 to 18 (mean = 8.2) and from 0.214 to 0.771 (mean = 0.595), respectively. Especially, the accession originated from Korea revealed average allele number of 6.0 (2 - 11) and average PIC value of 0.58 (0.193 - 0.763). Three groups were deduced by phylogenic analysis (Group-1, -2, -3); Korean accessions showed close genetic similarity to Japanese and USA accessions, and Korean landraces were mainly included in Group-3. We try to elaborate the genetic diversity analysis of conserved potato germplasm by acquiring more genotypes using applicable molecular markers.

• Journal of Microbiology and Biotechnology
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• v.22 no.4
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• pp.516-525
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• 2012

LAB were isolated from makgeolli locally produced around Jinju, Gyeongnam, S. Korea during spring of 2011. Randomly selected 11 isolates from MRS agar plates were identified first by API CHL 50 kits and then 16S rRNA gene sequencing. All 11 isolates were identified as Lactobacillus plantarum. Among them, ST4 grew in MRS broth with ethanol up to 10%, showing the highest alcohol resistance. L. plantarum ST4 was moderately resistant against acid and bile salts. When cellular proteins of L. plantarum ST4 under ethanol stress were analyzed by two-dimensional gel electrophoresis (2DE), the intensities of 6 spots increased, whereas 22 spots decreased at least 2-fold. Those 28 spots were identified by peptide mass fingerprinting (PMF). FusA2 (elongation factor G) increased 18.8-fold (6% ethanol) compared with control. Other proteins were AtpD (ATP synthase subunit beta), DnaK, GroEL, Tuf (elongation factor Tu), and Npr2 (NADH peroxidase), respectively. Among the 22 proteins decreased in intensities, lactate dehydrogenases (LdhD and LdhL1) were included.

• The Plant Pathology Journal
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• v.34 no.4
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• pp.269-285
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• 2018

Bacterial leaf blight is a major disease of eucalypt, especially under nursery conditions. Different bacterial species have been associated with the disease in several countries, and despite its importance worldwide, it is not clear to date whether similar disease symptoms are caused by the same or by different etiological agents. In this study, 43 bacterial strains were isolated from blighted eucalypt leaves collected in different geographic areas of Brazil and inoculated onto a susceptible eucalypt clone. Polyphasic taxonomy, including morphological, physiological, biochemical, molecular, and pathogenicity tests showed that only certain strains of Xanthomonas axonopodis caused symptoms of the disease. Strains varied in their aggressiveness, but no correlation with geographic origin was observed. MLSA-based phylogenetic analysis using concatenated dnaK, fyuA, gyrB and rpoD gene sequences allocated the strains in a well-defined clade, corresponding to Rademarker's group RG 9.6. Inoculation of nineteen plant species belonging to seven botanical families with representative strain LPF 602 showed it to be pathogenic only on Eucalyptus spp, and Corymbia spp. Based on distinct biochemical and pathogenic characteristics that differentiate the eucalypt strains from other pathovars of the X. axonopodis species, here we propose their allocation into the new pathovar X. axonopodis pv. eucalyptorum pv. nov.

• Korean Journal of Environmental Biology
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• v.25 no.4
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• pp.356-362
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• 2007

The rhizobacterial diversity associated with 9 native plant species inhabiting coastal sand dunes in Tae-an area, Chungnam Province, was studied using the denaturing gradient gel electrophoresis (DGGE) fingerprinting analysis over three times from October 2003 to March 2004. One dominant band commonly occurred in all of the rhizosphere samples, which was identified as that of Lysobacter enzymogenes. The other common bands included those derived from species of Pseudomonas and Bacillus. It was notable that L. enzymogenes was dominant in all of the 9 plant species and such dominance was consistent throughout the whole sampling period, which confirms the previous study by Lee et al. (2006a). The Bacillus bands were detected in all of the three samplings, and those of Pseudomonas were notable in the samples of December 2003. By the DGGE analysis alone, the significance of Lysobacter to the sand dune plants is not clear. However, considering their presence in healthy plants and the dominance in all plant species, Lysobacter may have positive roles in the survival or growth of the plants in sand dune area.

• Korean Journal of Veterinary Research
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• v.47 no.1
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• pp.33-41
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• 2007

Streptococcus spp. comprising Streptococcus (S.) uberis S. dysgalactiae strains is major causeof bovine mastitis from particularly well-managed or low somatic cell count herds that have successfullycontrolled contagious pathogens. In this study, antimicrobial susceptibility and genetic characteristics of S.uberis isolated from clinical or subclinical mastitis milk at 2003 were investigated. Eighty seven isolatesof Streptococus spp. were identified by the conventional biochemical methods. The antimicrobialsusceptibility by disk diffusion method was determined for 46 S. uberis, 11 S. bovis, 10 S. oralis, 6 S.uberis and 14 other Streptococcus spp.. Overall, the tested strains were susceptible to tetracycline (11.5%),amikacin (14.9%), streptomycin (16.1%), neomycin (26.4%), kanamycin (35.6%), gentamicin (65.2%),oxacillin (70.1%), ampicillin (75.9%), chloramphenicol (78.2%), and cephalothin (97.7%). Additionally, S.uberis strains were susceptible to pencillin G (97.8%), but resistant to erythromycin (76.0%) by minimalinhibitory concentration test. The multiple-drug resistance rate of isolated bacteria to 4 more thanamplification fingerprinting patterns amplifed with primer 8.6d showed that 3 to 8 number of distinguishableDNA fragments ranged from 180 bp to 1,20 bp. Thirty seven isolates of S. uberis strains were subtypedinto 8 distinct patterns. Each subtype revealed a typical pattern of antimicrobial susceptibilities. Thesefindings demonstrate that S. uberis isolates were mastitis pathogens of diverse serotypes, and oftenencountered the diverse resistant patterns.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.2
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• pp.94-101
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• 2008

In Korean waters, there are two color types (blue and purple) of the blue crab Portunus trituberculatus. The blue type is common, but the ratio of the purple type has increased in landings. To determine whether there were significant morphometric or genetic differences between the blue and purple types, crabs caught from the West Sea of Korea were examined. Based on covariance analysis, there were significant differences in 1 of 10 morphometric characteristics of males between the two types, in none of the ten characteristics for females. Using amplified fragment length polymorphism (AFLP) DNA fingerprinting, no specific AFLP marker was detected for each type. The heterozygosity and genetic diversity were very low. Analyses of pairwise distance, the Fst index, and genetic similarity revealed similar results, with very low genetic differentiation. Therefore, there is no significant difference between blue and purple types of the crab from the West Sea of Korea, and the two types in the West Sea can be managed as one stock.

• Development and Reproduction
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• v.4 no.2
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• pp.147-152
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• 2000

Four clonal lines of ayu, Plecoglossus altivelis, were produced through gynogenesis, mixed before hatching and reared communally. After 10 months, a randomly taken sample was subjected to a standardized shallow water stressor. Hematocrit, hemoglobin, red blood cells count (RBC) and mean corpuscular volume (MCV) were obtained from stressed and non-stressed fish. DNA fingerprinting was used to confirm the clonal nature of the organisms and to identified the clonal line to which each fish belonged. 1 observed significant differences between clona] lines mostly in the hematocrit and MCV measured under no-stress conditions. Such differences are suggested to represent mainly genetic variance, on account of the common environment provided to all the experimental groups. The stress response ratio was lower than expected, mainly due to some unexpectedly high non-stress values. Heritability values (h$^2$) were medium to high for the no-stress measurements (mean 0.238) and very low or zero for the stressed groups'traits (excepting one high value of 0.484). 1 conclude that the use of communally reared clonal lines represents a good tool for the characterization of the physiological traits, thus allowing for their utilization as genetic selection criteria.

• Korean Journal of Microbiology
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• v.53 no.3
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• pp.163-169
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• 2017

Strains D4 and D5 were isolated from peach-rotten soil during the peach harvest season. The isolates were identified based on morphological and biochemical characterization, and identification was determined by 16S rRNA gene sequencing. Results showed that D4 has high similarity to Lactobacillus plantarum ATCC $14917^T$ and Lactobacillus pentosus ATCC $8041^T$ at 99.05% and 98.98%, respectively. D5 was also similar to Lactobacillus pentosus ATCC $8041^T$ and Lactobacillus plantarum ATCC $14917^T$ at 98.71% and 98.64%, respectively. In contrast, isolates showed differences in carbohydrate utilization in comparison to Lactobacillus plantarum ATCC $14917^T$ and Lactobacillus pentosus ATCC $8041^T$. In view of this we performed VITEK MS matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) analysis, multiplex PCR fingerprinting, and random amplified polymorphic DNA (RAPD)-PCR to further confirm the identification of D4 and D5. The results of these analyses showed that both strains were most similar to Lactobacillus plantarum.