• Weed & Turfgrass Science
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• v.6 no.2
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• pp.151-156
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• 2017

Summer patch is the most serious disease at turfgrass field or golf course established with Kentucky bluegrass during high temperature season in Korea. Nevertheless, chemicals for the summer patch control are not yet registered in Korea. We isolated the pathogens from the turfgrass showing typical summer patch symptoms and identified as Magnaporthiopsis poae by using the internal transcribed spacer ITS1 and ITS4 sequences of rDNA. The inhibition rates of the pathogen were investigated for 10 fungicides. As results, the pathogen growth was suppressed when chemicals concentration increased and negatively correlated with incubation period with the chemicals. In triazole group, all chemicals (metconazole, myclobutanil, propiconazole and tebuconazole) treated showed the inhibition rates by 100%. Thiophanate-methyl showed the next highest inhibition effect against a summer patch pathogen. In strobilurin group, pyraclostrobin was the highest suppression effect compared with azoxystrobin and trifloxystrobin. Inhibition effect of fludioxonil and fluxapyroxad on pathogen was similar to the trifloxystrobin. Based on the results, triazole and carboxamide groups are strongly recommended due to the highest inhibition effect on the summer patch pathogen, Magnaporthiopsis poae.

• Journal of Mushroom
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• v.18 no.1
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• pp.100-106
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• 2020

Eight morel mushroom species were collected from Korea and other countries. The culture characteristics, genetic relationships, and beta-glucan content of the strains were analyzed. The mycelia of Morchella species exhibited optimal growth when cultured in dark at 25 ℃ in media with pH 7. The mycelia had a distinctive mycelial scent and characteristically changed color, being white initially, and then turning dark yellow to dark brown as it grew. The mycelia were classified into five types based on morphology. The isolates were identified as Morchella conica, two M. sextelata, M. importuna, M. esculenta, and three M. crassipes, based on ITS-rDNA sequences. PCR polymorphisms were variably produced within Morchella spp. using Universal Fungal Fingerprinting Primers (UFPF) and classified into four groups at the intra and inter species level. The strains, KMCC04971 and KMCC04407, showed the same banding pattern as M. conica and M. sextelata, respectively; however, these results were different from those of ITS analysis. Glucan content analysis by strain showed that the KMCC 04973 strain of M. importuna had the highest alpha- and beta-glucan content, at 16.4 g and 33.1 g per 100 g, respectively.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.669-673
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• 2008

For the development of a biological control method against B. cereus in cheonggukjang, 20 Bacillus spp. were isolated from the naturally fermented baektae and heuktae cheonggukjang, identified by using 16S rDNA sequences. Among the isolated strains, Bacillus sp. SC-8 was selected using the B. cereus lawn cell assay as an antagonistic microorganism against B. cereus. The culture medium of Bacillus sp. SC-8 after 24 hr of incubation at $37^{\circ}C$ also evidenced a high level of antagonistic activity. In cheonggukjang fermented with the mixed culture of Bacillus sp. SC-8 and B. cereus, antagonistic effect against B. cereus was maintained during the fermentation of cheonggukjang, while its effect was reduced during storage at $4^{\circ}C$ due to the decrement of cell population of Bacillus sp. SC-8. In Bacillus sp. SC-15, which was utilized a control, antagonistic activity against B. cereus was not demonstrated on the lawn cell plate assay and culture medium, but its effects were detected in cheonggukjang. Therefore, the production of antagonistic substances of Bacillus spp. depends on the fermentative environment.

• Korean Journal of Environmental Agriculture
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• v.39 no.1
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• pp.65-74
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• 2020

BACKGROUND: Soil carbon sequestration has been investigated for a long time because of its potential to mitigate the greenhouse effect. No- or reduced tillage, crop rotations, or cover crops have been investigated and practiced to sequester carbon in soils but the roles of soil biota, particularly microorganisms, have been mostly ignored although they affect the amount and stability of soil organic matters. METHODS AND RESULTS: In this study we analyzed the organic matter and microbial community in organically cultivated corn field soils where no-tillage (NT) or conventional tillage (CT) had been practiced for about three years. The amounts of organic matter and recalcitrant carbon pool were 18.3 g/kg dry soil and 4.1 g C/kg dry soil, respectively in NT soils, while they were 12.4 and 2.5, respectively in CT soils. The amounts of RNA and DNA, and the copy numbers of bacterial 16S rRNA genes and fungal ITS sequences were higher in NT soils than in CT soils. No-tillage treatment increased the diversities of soil bacterial and fungal communities and clearly shifted the bacterial and fungal community structures. In NT soils the relative abundances of bacterial phyla known as copiotrophs, Betaproteobacteria and Bacteroidetes, increased while those known as oligotrophs, Acidobacteria and Verrucomicrobia, decreased compared to CT soils. The relative abundance of a fungal phylum, Glomeromycota, whose members are known as arbuscular mycorrhizal fungi, was about two time higher in NT soils than in CT soils, suggesting that the higher amount of organic matter in NT soils is related to its abundance. CONCLUSION: This study shows that no-tillage treatment greatly affects soil microbial abundance and community structure, which may affect the amount and stability of soil organic matter.

• Journal of Veterinary Clinics
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• v.32 no.2
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• pp.158-161
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• 2015

Bacterial dermatitis is common disease that is necessary to treat with antibiotics. In recent, antibiotic-resistant bacteria is being increased in worldwide. The purpose of the present study was to evaluate the prevalence of resistant genes in Staphylococcus (S.) pseudintermedius isolated from dogs, and to compare the resistant gene profile with the result of antibiotic disc diffusion test. A total of seven S. pseudintermedius was included in the study. Bacterial identification was performed by 16S ribosomal RNA gene sequence analysis. S. pseudintermedius isolates had more than one antibiotic resistant gene (mecA, blaZ and aac(6')/aph(2"). While all isolates were PCR positive to blaZ gene, only two isolates were resistant to amoxicillin/clavulanate. Among five isolates harboring gentamicin resistance, one isolate was negative to aac(6')/aph(2")-targeted PCR. Taken together, the results suggest that resistant gene-targeted PCR and disc diffusion test are complementary to detect antibiotic resistance.

• Korean Journal of Microbiology
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• v.40 no.3
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• pp.237-243
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• 2004

The aim of this study is to investigate the detection rate of putative periodontopathogens, Porphyromonas gingivalis, Tannerella forsythia, and Actiobacillus actinomycetemcomitans, related to cardiovascular diseases(CVD). Plaques were sampled from 15 subjects (4 sites of denture base and/or tooth) with sterilized explorers and were transported in IX PBS. The detection of periodontopathogens was performed by polymerase chain reaction with species-specific primers based on 16S rDNA. The PCR products were cloned into pGEM-T easy vector and its nucleotides were sequenced in order to confirm the specificity. Our data showed that the detection rate of P. gingivalis and T forsythia in denture base of edentulous patients was 25％ and 75％, respectively. And the detection rate of P. gingivalis and T.forsythia in denture base of patient having one more tooth was 91％. The results indicate that plaque of denture base may serve as reservoirs of oral bacteria related to CVD.

• Applied Biological Chemistry
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• v.38 no.2
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• pp.111-117
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• 1995

In Escherichia coli, CRP forms a complex with cAMP and acts as a transcriptional regulator of many genes, including sugar metabolism operons. The E. coli MK2001, which is introduced the altered crp, is functional in the expression of lac, ara and man, in the absence of cAMP. However, the expression of mal gene is fully activated by the addition of cAMP or cGMP. The object of the study is cloning of the sfs (sugar fermentation stimulation) genes, which was involved in regulation of mal gene expression with the altered crp gene, and structural analysis and characterization of the genes at the molecular level. We have cloned 5 different E. coli genes which stimulate the maltose metabolism in a crp, cya::km (MK2001) background. Newly identified genes were designated as sfs. One of the sfs genes (pPC1), located at the 53.2 min map position on the E. coli chromosome, was further analyzed. Expression of the genes, which is involved in maltose metabolism, malQ (amylomaltase), was increased to 5.8-fold in the presence of a plasmid, pAP5, containing the subcloned sfs4 gene. The nucleotide seguence of a common 2,126 bp segment of the pPCM1 was determined and two open reading frames (ORF1 and ORF2) were detected. The ORF1 encodes the sfs4 gene and ORF2 encodes a truncated protein. Potential CRP binding site is located in the upstream of the putative promoter in the regulatory region. Expression of the cloned sfs4 gene was positively regulated by the cAMP-CRP complex.

• Applied Biological Chemistry
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• v.15 no.2
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• pp.163-168
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• 1972

Previously identified female pupae were X-irradiated with a dose of 1000r one day prior to moth transformation. Female mothes from irradiated and non-irradiated pupae were copulated with normal male ones and allowed to lay eggs. Fertilized eggs were collected at 6 intervals such as 5, 15, 45, 90 minutes, 12 and 40 hours after laying, and deep-freezed immediately after each collection until measurements. RNase activity and nucleic acid content were determined with each sample and following results were obtained. 1) It was proved to exist two RNases in silk worm eggs as in mammalian tissues, one active maximally at pH 5.8 and the other at pH 8.0, and the acid RNase activity was much higher than that of alkaline RNase. 2) The activity of acid and alkaline RNases increased remarkably during early development of the embryo of silk worm eggs, reaching the maximum activity at 45 minutes from laying time in non-irradiated group. There was no appreciable difference in two RNase activities for 45 minutes after laying in both control and irradiated groups, but the activity of acid and alkaline RNases in latter group was three times as much as that in former group, at 90 minutes from laying time and it was also found the acid RNase activity was 1.8 times higher than alkaline one in irradiated group. 3) The RNA-P content of control group increased considerably for initial 45 minutes, followed by a decline 45 minutes later with sight but steady increase thereafter. The RNA-P content of irradiated group, however, increased at initial 5 minutes, followed by a marked fall 90 minutes after laying, with no change thereafter. The DNA-P of control group showed a sharp increase for initial 45 minutes, followed by a decline 45 minutes later with no appreciable change thereafter, whereas that of irradiated group showed an increase at initial 15 minutes, followed by a sharp decline for following 45 minutes with a gradual increase thereafter. It was thus proved that the synthesis of nucleic acid in silk worm eggs was much suppressed by X-irradiation during early development of embryo. 4) The RNase activity varied in parallel with the RNA-P content in control group, but the RNA-P content in irradiated group was shown to be minimum value in concidence with the maximum activity of both RNases.

• Journal of Microbiology and Biotechnology
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• v.15 no.2
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• pp.287-295
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• 2005

In order to compare bacteria] community structure and diversity in activated sludges, terminal restriction fragment length polymorphism (T-RFLP) of PCR-amplified 16s rDNAs was analyzed for 31 domestic and industrial wastewater treatment plants (WTPs). Regardless of the characteristics of the wastewaters, the bacteria] community structures of activated sludges appeared diverse and complex. In particular, activated sludges in domestic WTPs contained higher bacterial diversity than those in industrial WTPs. It was also found that terminal restriction fragment (T-RF) profiles derived from domestic WTPs were very similar with each other, although activated sludges were collected from different plants at different locations. Interestingly, activated sludges of a WTP where restaurant and toilet sewages of a company were managed showed a bacterial community structure similar to that of domestic WTPs. Activated sludges in leather industria] WTPs also showed a high similarity. However, other wastewaters possessed different bacterial communities, so that overall similarity was as low as about $30\%$. Since activated sludges from WTPs for domestic wastewaters and a company sewage appeared to hold similar bacterial communities, it was necessary to confirm if similar wastewaters induce a similar bacterial community. To answer this question, analysis of T-RFs for activated sludges, taken from another 12 domestic WTPs, was conducted by using a 6­FAM$^{TM}$-Iabeled primer and an automated DNA sequencer for higher sensitivity. Among 12 samples, it was again found that T-RF profiles of activated sludges from Yongin, Sungnam, Suwon, and Tancheon domestic WTPs in Kyonggi-do were very similar with each other. On the other hand, T-RF profiles of activated sludges from Shihwa and Ansan WTPs were quite different from each other. It was thought that this deviation was caused by wastewaters, since Ansan and Shihwa WTPs receive both domestic and industrial wastewaters. From these results, it was tentatively concluded that similar bacterial communities might be developed in activated sludges, if WTPs treat similar wastewaters.

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.909-916
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• 2004

CCAAT/enhancer binding proteins(C/EBP) are a group of transcription factors expressed during preadipocyte differentiation. In the C/EBPs, C/EBPa plays an important role in lipid deposition and adipocyte differentiation. In this studies, we report the identification, characterization, and expression of a Hanwoo CIEBP$\alpha$ The Hanwoo C/EBP$\alpha$DNA includes a 1059 bp open reading frame encoding a protein of 353 amino acids. The CIEBPa amino acid sequences of the Hanwoo show strong conservation with the corresponding sequences reported in other species. The distribution of C/EBP$\alpha$ mRNA in various tissues of Hanwoo aged 12 months were investigated using Northern blotting analysis. The highest expression was detected in adipose tissue and more lower expression was detected in colon and lung. We also identified expression of C/EBPa mRNA in Hanwoo sirloin and adipose tissue aged 12, 26, and 30 months by real-time RT-PCR. The higest expression were detected at 26 months in the sirloin and at 12 and 26 months in the adipose tissue.