• Microbiology and Biotechnology Letters
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• v.38 no.1
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• pp.24-31
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• 2010

For the research of the natural marine antioxidant, an antioxidant-producing marine actinomycetes was isolated from sea water in Jeju coastal area. The strain was identified based on 16S rDNA sequencing, the morphology by a method of scanning electron microscopy, physiological and biochemical characteristics and cellular fatty acid analysis. The isolated strain ACT-18 was gram positive, aerobic, non-motile spores. Substrate mycelia are dark green and yellow gray aerial mycelia. The cell size of the strain was $0.5{\sim}1.0\;{\mu}m$. 16S rDNA sequence analysis showed that were Gram-positive bacteria grouped on Streptomyces sp. Results of cellular fatty acid analysis showed that major cellular fatty acids were $C_{15:0}$ anteiso (39.33%), $C_{16:1}$ cis 9 (11.96%), $C_{16:0}$ (13.08%) and $C_{17:0}$ anteiso (10.99%). The antioxidant activity of methanol extract from Streptomyce sp. ACT-18 was evaluated by measuring 1,1-diphenyl- 2-picrylhydrazyl (DPPH), hydroxyl, and alkyl radical scavenging activity using an electron spin resonance (ESR) spectrometer. DPPH radical scavenging activity of SBME (Streptomyces Broth Methanol Extract) A-18 was 46% at 0.1 mg/mL. Hydroxyl radical scavenging activity of SBME A-18 was 63% at 0.1 mg/mL. Alkyl radical scavenging activity of SBME A-18 was 39% at 0.1 mg/mL.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.173-180
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• 2000

The intern1 spacer regions (ISR) between the 16s and 23s $1_RNA$ genes of Aeronzonus iwonii blogroupsobria and A. caviae were investigated by PCR fragment length typing and DNA sequencing. A. iwonii bv.sobria has a speciIic 16s-23s pattern of 2-4 fiagments ranging Goin 479-539 bp, with the exception of thespecies Aeron7onns cmiae, which has 3 fragments ranglog from 470-602 bp. In all of the.4 vei*onii bv. sobr,iaand A, caviae strains examined in this study, the 470-481bp Tragnent, designated TSR-1, invariably contained $tDNA^{uc(GAT)$ and $tDNA^{Ala(TGC)$ in contrast to ISR-2 (513-525 bp). ISR-3 (537-539 bp) and ISR-4 (568-602 bp)containing TEX>$tDNA^{Olu(ITC)$ A stretch of 20 nucleotides (178-197 bp) in the ISR-4 was conserved only wit11mA.caiiue, from which the A. caiiae specific primer, named prAC-F, was designed and used for PCR with aAcaviae coimnon reverse primer A PCR product of 450 bp was apparent alnong I , caiizne strains, but not ii1.4.ijeronii bv. sob~ia strains. The PCR product was oot detected t"-om strains belonging to A. hjili-o~~hila, Ebrio,aud the family Ef\ulcornertei,obncteriaceae. This study provides the first molecular tool for mdentifying the species 8.caviae.ing the species 8. caviae.

• Korean Journal of Veterinary Research
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• v.36 no.1
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• pp.187-193
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• 1996

The T sergenti DNA fragments used as probes of KTS1(2.4kb) and KTS3(1.5kb) were labeled with digoxigenin-11-dUTP for the Southern hybridization. T sergenti DNAs from different geographic locations(Korea; Chonbuk, Kyungbuk, Chungnam, Kangwon, Cheju island, Japan; Shintoku, Shintoku 9209, Shintoku 9201, Shintoku 9202, Shintoku 9102) which had been digested with Pst I and EcoR I were probed by the digoxigenin-11-dUTP-labeled KTS1 and KTS3. As the results, the samples from Chonbuk, Kyungbuk, Cheju island in Korea and Shintoku, Shintoku 9209, Shintoku 9201, Shintoku 9102 in Japan were positively reacted, but the others from the other locations not reacted. In the comformation test of T sergenti DNA from different geographic locations, all of the samples were positively detected by PCR amplification.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.360-370
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• 2012

Current ecological knowledge of methanotrophic biofilms is incomplete, although they have been broadly studied in biotechnological processes. Four individual DNA samples were prepared from a methanotrophic biofilm, and a multiplex 16S rDNA pyrosequencing was performed. A complete library (before being de-multiplexed) contained 33,639 sequences (average length, 415 nt). Interestingly, methanotrophs were not dominant, only making up 23% of the community. Methylosinus, Methylomonas, and Methylosarcina were the dominant methanotrophs. Type II methanotrophs were more abundant than type I (56 vs. 44%), but less richer and diverse. Dominant non-methanotrophic genera included Hydrogenophaga, Flavobacterium, and Hyphomicrobium. The library was de-multiplexed into four libraries, with different sequencing efforts (3,915 - 20,133 sequences). Sorrenson abundance similarity results showed that the four libraries were almost identical (indices > 0.97), and phylogenetic comparisons using UniFrac test and P-test revealed the same results. It was demonstrated that the pyrosequencing was highly reproducible. These survey results can provide an insight into the management and/or manipulation of methanotrophic biofilms.

• Environmental Engineering Research
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• v.11 no.4
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• pp.173-180
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• 2006

Autotrophic nitrogen removal and its microbial community from a laboratory scale upflow anaerobic sludge bed reactor were characterized with dynamic behavior of nitrogen removal and sequencing result of molecular technique (DNA extraction, PCR and amplification of 16S rDNA), respectively. In the experiment treating inorganic wastewater, the anaerobic granular sludge from a full-scale UASB reactor treating industrial wastewater was inoculated as seed biomass. The operating results revealed that an addition of hydroxylamine would result in lithoautotrophic ammonium oxidation to nitrite/nitrate, and also hydrazine would play an important role for the success of sustainable nitrogen removal process. Total N and ammonium removal of 48% and 92% was observed, corresponding to nitrogen conversion of 0.023 g N/L-d. The reddish brown-colored granular sludge with a diameter of $1{\sim}2\;mm$ was observed at the lower part of sludge bed. The microbial characterization suggests that an anoxic ammonium oxidizer and an anoxic denitrifying autotrophic nitrifier contribute mainly to the nitrogen removal in the reactor. The results revealed the feasibility on development of high performance lithoautotrophic nitrogen removal process with its microbial granulation.

• Parasites, Hosts and Diseases
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• v.58 no.6
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• pp.689-694
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• 2020

Strongyloidiasis is caused by Strongyloides stercoralis and is one of the most neglected tropical diseases in tropical and subtropical regions. Although several strongyloidiasis cases have been reported in Korea, genetic analysis of Korean isolates is still incomplete. In this study, a parasite was isolated from a 61-year-old man diagnosed with strongyloidiasis during the treatment of lymphoma on his retroperitoneal lymph node. Diffuse symmetric wall thickening from the ascending to descending colon and a nematode-infected intestine was observed following microscopic examination. Genomic DNA was isolated from a patient tissue block, and S. stercoralis was identified by PCR and sequencing (18S rDNA). In order to determine phylogenetic location of a Korean isolate (named KS1), we analyzed cox1 gene (500-bp) and compared it with that from 47 previous S. stercoralis isolates (28 human isolates and 19 canid isolates) from Asian countries. Our results showed that phylogenetic tree could clearly be divided into 5 different groups according to hosts and regions. KS1 was most closely related with the Chinese isolates in terms of genetic distance.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.24 no.1
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• pp.30-37
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• 2021

Purpose: To investigate the differences in the colon microbiota composition of Hirschsprung's disease (HSCR) patients with and without a history of postoperative Hirschsprung's associated enterocolitis (HAEC). Methods: Colon tissue microbiota was characterized by bacterial deoxyribonucleic acid (DNA) extraction and 16S rDNA sequencing for taxonomic classification and comparison. Results: The sequence diversity richness within samples was significantly higher in samples from patients with a history of postoperative HAEC. We observed an increased relative abundance of the phyla Bacteroidetes, Firmicutes and Cyanobacteria in HAEC patients and Fusobacteria, Actinobacteria and Proteobacteria in HSCR patients and, an increased relative abundance of the genera Dolosigranulum, Roseouria and Streptococcus in HAEC patients and Propionibacterium and Delftia in HSCR patients. Conclusion: Our findings provide evidence that the colon tissue microbiota composition is different in HSCR patients with and without postoperative HAEC.

• The Plant Pathology Journal
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• v.37 no.3
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• pp.280-290
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• 2021

Population genetic studies of Hemileia vastatrix have been conducted in order to describe the evolutionary dynamics of the pathogen and the disease epidemiology as consequence of changes in disease management and host distribution occurred in Peru after the 2013 epidemic. These analyses were performed by sequencing the internal transcribed spacers of the nuclear ribosomal DNA (rDNA-ITS) of H. vastatrix collected from two coffee growing areas in 2014 and 2018. H. vastatrix population showed high haplotype diversity (Hd = 0.9373 ± 0.0115) with a low nucleotide diversity (π = 0.00322 ± 0.00018). Likewise, AMOVA indicated that fungus population has behaved as a large population without structuring by geographical origin and sampling years (F_ST = 0.00180, P = 0.20053 and F_ST = 0.00241, P = 0.19693, respectively). Additionally, the haplotype network based on intraspecific phylogenetic analysis of H. vastatrix using Peruvian and NCBI sequences revealed that Peruvian ancestral haplotypes, which were maintained in time and space, would correspond to the reported sequences of the races II and XXII. This result suggests that no substantial changes have occurred through time in Peruvian Hemileia vastatrix population.

• Journal of Microbiology and Biotechnology
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• v.16 no.1
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• pp.77-83
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• 2006

A gene encoding a $\gamma-butyrolactone$ autoregulator receptor was cloned from Saccharopolyspora erythraea, and the biochemical characteristics, including the autoregulator specificity, were determined with the purified recombinant protein. Using primers designed for the conserved amino acid sequence of Streptomyces $\gamma-butyrolactone$ autoregulator receptors, a 120 bp S. erythraea DNA fragment was obtained by PCR. Southern and colony hybridization with the 120 bp fragment as a probe allowed to select a genomic clone of S. erythraea, pESG, harboring a 3.2 kb SacI fragment. Nucleotide sequencing analysis revealed a 615 bp open reading frame (ORF), showing moderate homology (identity, $31-34\%$; similarity, $45-47\%$) with the $\gamma-butyrolactone$ autoregulator receptors from Streptomyces sp., and this ORF was named seaR (Saccharopolyspora erythraea autoregulator receptor). The seaR/pET-3d plasmid was constructed to overexpress the recombinant SeaR protein (rSeaR) in Escherichia coli, and the rSeaR protein was purified to homogeneity by DEAE-Sephacel column chromatography, followed by DEAE-ion-exchange HPLC. The molecular mass of the purified rSeaR protein was 52 kDa by HPLC gel-filtration chromatography and 27 kDa by SDS-polyacrylamide gel electrophoresis, indicating that the rSeaR protein is present as a dimer. A binding assay with tritium-labeled autoregulators revealed that rSeaR has clear binding activity with a VB-C-type autoregulator as the most effective ligand, demonstrating for the first time that the erythromycin producer S. erythraea possesses a gene for the $\gamma-butyrolactone$autoregulator receptor.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3997-4003
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• 2014

Background: Infection with certain human papillomavirus (HPV) genotypes is the most important risk factor related with cervical cancer. The objective of the present study was to investigate the prevalence of HPV infection, the distribution of HPV genotypes and HPV E6/E7 oncogene mRNA expression in Turkish women with different cervical cytological findings in Mersin province, Southern Turkey. Materials and Methods: A total of 476 cytological samples belonging to women with normal and abnormal cervical Pap smears were enrolled in the study. For the detection and genotyping assay, a PCR/direct cycle sequencing approach was used. E6/E7 mRNA expression of HPV-16, 18, 31, 33, and 45 was determined by type-specific real-time NASBA assay (NucliSENS EasyQ$^{(R)}$HPV v1.1). Results: Of the 476 samples, 106 (22.3%) were found to be positive for HPV DNA by PCR. The presence of HPV was significantly more common (p<0.001) in HSIL (6/8, 75%) when compared with LSIL (6/14, 42.9%), ASC-US (22/74, 29.7%) and normal cytology (72/380, 18.9%). The most prevalent genotypes were, in descending order of frequency, HPV genotype 66 (22.6%), 16 (20.8%), 6 (14.2%), 31 (11.3%), 53 (5.7%), and 83 (4.7%). HPV E6/E7 oncogene mRNA positivity (12/476, 2.5%) was lower than DNA positivity (38/476, 7.9%). Conclusions: Our data present a wide distribution of HPV genotypes in the analyzed population. HPV genotypes 66, 16, 6, 31, 53 and 83 were the predominant types and most of them were potential carcinogenic types. Because of the differences between HPV E6/E7 mRNA and DNA positivity, further studies are required to test the role of mRNA testing in the triage of women with abnormal cervical cytology or follow up of HPV DNA positive and cytology negative. These epidemiological data will be important to determine the future impact of vaccination on HPV infected women in our region.