• Journal of Microbiology and Biotechnology
• /
• 제30권4호
• /
• pp.505-514
• /
• 2020

The symbiotic nature of the relationship between algae and marine bacteria is well-studied among the complex microbial interactions. The mutual profit between algae and bacteria occurs via nutrient and vitamin exchange. It is necessary to analyze the genome sequence of a bacterium to predict its symbiotic relationships. In this study, the genome of a marine bacterium, Pseudoruegeria sp. M32A2M, isolated from the south-eastern isles (GeoJe-Do) of South Korea, was sequenced and analyzed. A draft genome (91 scaffolds) of 5.5 Mb with a DNA G+C content of 62.4% was obtained. In total, 5,101 features were identified from gene annotation, and 4,927 genes were assigned to functional proteins. We also identified transcription core proteins, RNA polymerase subunits, and sigma factors. In addition, full flagella-related gene clusters involving the flagellar body, motor, regulator, and other accessory compartments were detected even though the genus Pseudoruegeria is known to comprise non-motile bacteria. Examination of annotated KEGG pathways revealed that Pseudoruegeria sp. M32A2M has the metabolic pathways for all seven vitamin Bs, including thiamin (vitamin B1), biotin (vitamin B7), and cobalamin (vitamin B12), which are necessary for symbiosis with vitamin B auxotroph algae. We also identified gene clusters for seven secondary metabolites including ectoine, homoserine lactone, beta-lactone, terpene, lasso peptide, bacteriocin, and non-ribosomal proteins.

• Journal of Microbiology and Biotechnology
• /
• 제30권7호
• /
• pp.974-981
• /
• 2020

Sequence type 410 (ST410) of Escherichia coli is an extraintestinal pathogen associated with multi drug resistance. In this study, we aimed to investigate the horizontal propagation pathway of a high-risk clone of E. coli ST410 that produces Klebsiella pneumoniae carbapenemase (KPC). blaKPC-encoding E. coli and K. pneumoniae isolates were evaluated, and complete sequencing and comparative analysis of blaKPC-encoding plasmids from E. coli and K. pneumoniae, antimicrobial susceptibility tests, polymerase chain reaction, multilocus sequence typing, and conjugal transfer of plasmids were performed. Whole-genome sequencing was performed for plasmids mediating KPC-2 production in E. coli and K. pneumoniae clinical isolates. Strains E. coli CPEc171209 and K. pneumoniae CPKp171210 were identified as ST410 and ST307, respectively. CPEc171209 harbored five plasmids belonging to serotype O8:H21, which is in the antimicrobial-resistant clade C4/H24. The CPKp171210 isolate harbored three plasmids. Both strains harbored various additional antimicrobial resistance genes. The IncX3 plasmid pECBHS_9_5 harbored blaKPC-2 within a truncated Tn4401a transposon, which also contains blaSHV-182 with duplicated conjugative elements. This plasmid displayed 100% identity with the IncX3 plasmid pKPBHS_10_3 from the K. pneumoniae CPKp171210 ST307 strain. The genes responsible for the conjugal transfer of the IncX3 plasmid included tra/trb clusters and pil genes coding the type IV pilus. ST410 can be transmitted between patients, posing an elevated risk in clinical settings. The emergence of a KPC-producing E. coli strain (ST410) is concerning because the blaKPC-2-bearing plasmids may carry treatment resistance across species barriers. Transgenic translocation occurs among carbapenem-resistant bacteria, which may spread rapidly via horizontal migration.

• Journal of Ginseng Research
• /
• 제37권2호
• /
• pp.227-247
• /
• 2013

MicroRNAs (miRNAs) are a class of recently discovered non-coding small RNA molecules, on average approximately 21 nucleotides in length, which underlie numerous important biological roles in gene regulation in various organisms. The miRNA database (release 18) has 18,226 miRNAs, which have been deposited from different species. Although miRNAs have been identified and validated in many plant species, no studies have been reported on discovering miRNAs in Panax ginseng Meyer, which is a traditionally known medicinal plant in oriental medicine, also known as Korean ginseng. It has triterpene ginseng saponins called ginsenosides, which are responsible for its various pharmacological activities. Predicting conserved miRNAs by homology-based analysis with available expressed sequence tag (EST) sequences can be powerful, if the species lacks whole genome sequence information. In this study by using the EST based computational approach, 69 conserved miRNAs belonging to 44 miRNA families were identified in Korean ginseng. The digital gene expression patterns of predicted conserved miRNAs were analyzed by deep sequencing using small RNA sequences of flower buds, leaves, and lateral roots. We have found that many of the identified miRNAs showed tissue specific expressions. Using the insilico method, 346 potential targets were identified for the predicted 69 conserved miRNAs by searching the ginseng EST database, and the predicted targets were mainly involved in secondary metabolic processes, responses to biotic and abiotic stress, and transcription regulator activities, as well as a variety of other metabolic processes.

• 농업과학연구
• /
• 제45권4호
• /
• pp.655-663
• /
• 2018

The insect gut microbiome is known to have important roles in host growth, development, digestion, and resistance against pathogens. In addition, the genetic diversity of the insect gut microbiota has recently been recognized as potential genetic resources for industrial bioprocessing. However, there is limited information regarding the insect gut microbiota to better help us understand their potential benefits for enhanced pig production. With the development of next-generation sequencing methods, whole genome sequence analysis has become possible beyond traditional culture-independent methods. This improvement makes it possible to identify and characterize bacteria that are not cultured and located in various environments including the gastrointestinal tract. Insect intestinal microorganisms are known to have an important role in host growth, digestion, and immunity. These gut microbiota have recently been recognized as potential genetic resources for livestock farming which is using the functions of living organisms to integrate them into animal science. The purpose of this literature review is to emphasize the necessity of research on insect gut microbiota and their applicability to pig production or bioindustry. In conclusion, bacterial metabolism of feed in the gut is often significant for the nutrition intake of animals, and the insect gut microbiome has potential to be used as feed additives for enhanced pig performance. The exploration of the structure and function of the insect gut microbiota needs further investigation for their potential use in the swine industry particularly for the improvement of growth performance and overall health status of pigs.

• 농업과학연구
• /
• 제45권3호
• /
• pp.385-400
• /
• 2018

Marker-assisted backcrossing (MABC) is useful for selecting offspring with a highly recovered genetic background for a recurrent parent at early generation unlike rice and other field crops. Molecular marker sets applicable to practical MABC are scarce in vegetable crops including tomatoes. In this study, we used the National Center for Biotechnology Information- short read archive (NCBI-SRA) database that provided the whole genome sequences of 234 tomato accessions and selected 27,680 tag-single nucleotide polymorphisms (tag-SNPs) that can identify haplotypes in the tomato genome. From this SNP dataset, a total of 143 tag-SNPs that have a high polymorphism information content (PIC) value (> 0.3) and are physically evenly distributed on each chromosome were selected as a MABC marker set. This marker set was tested for its polymorphism in each pairwise cross combination constructed with 124 of the 234 tomato accessions, and a relatively high number of SNP markers polymorphic for the cross combination was observed. The reliability of the MABC SNP set was assessed by converting 18 SNPs into Luna probe-based high-resolution melting (HRM) markers and genotyping nine tomato accessions. The results show that the SNP information and HRM marker genotype matched in 98.6% of the experiment data points, indicating that our sequence analysis pipeline for SNP mining worked successfully. The tag-SNP set for the MABC developed in this study can be useful for not only a practical backcrossing program but also for cultivar identification and F1 seed purity test in tomatoes.

• Journal of Animal Science and Technology
• /
• 제57권12호
• /
• pp.47.1-47.10
• /
• 2015

Background: Knowledge of linkage disequilibrium (LD) levels among different populations can be used to detect genetic diversity and to investigate the historical changes in population sizes. Availability of large numbers of SNP through new sequencing technologies has provided opportunities for extensive researches in quantifying LD patterns in cattle breeds. The aim of this study was to compare the extent of linkage disequilibrium among Iranian cattle breeds using high density SNP genotyping data. Results: A total of 70 samples, representing seven Iranian indigenous cattle breeds, were genotyped for 777962 SNPs. The average values of LD based on the $r^2$ criterion were computed by grouping all syntenic SNP pairwises for intermarker distances from 0 Kb up to 1 Mb using three distance sets. Average $r^2$ above 0.3 was observed at distances less than 30 Kb for Sistani and Kermani, 20 Kb for Najdi, Taleshi, Kurdi and Sarabi, and 10 Kb for Mazandarani. The LD levels were considerably different among the Iranian cattle breeds and the difference in LD extent was more detectable between the studied breeds at longer distances. Lower level of LD was observed for Mazandarani breed as compared to other breeds indicating larger ancestral population size in this breed. Kermani breed continued to have more slowly LD decay than all of the other breeds after 3 Kb distances. More slowly LD decay was observed in Kurdi and Sarabi breeds at larger distances (>100 Kb) showing that population decline has been more intense in more recent generations for these populations. Conclusions: A wide genetic diversity and different historical background were well reflected in the LD levels among Iranian cattle breeds. More LD fluctuation was observed in the shorter distances (less than 10 Kb) in different cattle populations. Despite of the sample size effects, High LD levels found in this study were in accordance with the presence of inbreeding and population decline in Iranian cattle breeds.

• Journal of Microbiology and Biotechnology
• /
• 제27권8호
• /
• pp.1419-1427
• /
• 2017

As probiotics play an important role in maintaining a healthy gut flora environment through antitoxin activity and inhibition of pathogen colonization, they have been of interest to the medical research community for quite some time now. Probiotic bacteria such as Lactobacillus plantarum, which can be found in fermented food, are of particular interest given their easy accessibility. We performed whole-genome sequencing and genomic analysis on a GB-LP1 strain of L. plantarum isolated from Korean traditional fermented food; this strain is well known for its functions in immune response, suppression of pathogen growth, and antitoxin effects. The complete genome sequence of GB-LP1 is a single chromosome of 3,040,388 bp with 2,899 predicted open reading frames. Genomic analysis of GB-LP1 revealed two CRISPR regions and genes showing accelerated evolution, which may have antibiotic and antitoxin functions. The aim of the present study was to predict strain specific-genomic characteristics and assess the potential of this new strain as lactic acid bacteria at the genomic level using in silico analysis. These results provide insight into the L. plantarum species as well as confirm the possibility of its utility as a candidate probiotic.

• Journal of Microbiology and Biotechnology
• /
• 제29권5호
• /
• pp.785-793
• /
• 2019

Black rot caused by Xanthomonas campestris pv. campestris (Xcc) is the most damaging disease in Brassica crops around the world. In this study, we developed a molecular marker specific to Xcc race 5. To do this, the available whole genome sequences of Xcc races/strains and Xc subspecies were aligned and identified a highly variable genomic region (XccR5-89.2). Subsequently, a primer set covering the 'XccR5-89.2' region was designed and tested against the genomic DNA of Xcc races/strains, Xc subspecies and other plant-infecting bacterial strains (Pseudomonas syringae pv. maculicola and Erwinia carotovora subsp. carotovora). The results showed that the 'XccR5-89.2' primer pair amplified a 2,172-bp fragment specific to Xcc race 5. Moreover, they also amplified a 1,515-bp fragment for Xcc race 1 and an over 3,000-bp fragment for Xcc race 3. However, they did not amplify any fragments from the remaining Xcc races/strains, subspecies or other bacterial strains. The 'XccR5-89.2' primer pair was further PCR amplified from race-unknown Xcc strains and ICMP8 was identified as race 5 among nine race-unknown Xcc strains. Further cloning and sequencing of the bands amplified from race 5 and ICMP8 with 'XccR5-89.2' primers revealed both carrying identical sequences. The results showed that the 'XccR5-89.2' marker can effectively and proficiently detect, and identify Xcc race 5 from Xcc races/strains, subspecies and other plant-infecting bacteria. To our knowledge, this is the first report for an Xcc race 5-specific molecular marker.

• 한국균학회지
• /
• 제49권1호
• /
• pp.33-44
• /
• 2021

본 연구에서는 국내에 유통되고 있는 40개 표고 품종들로부터 산백향과 설백향의 구분이 가능한 CAPS 마커를 개발하였다. 제한효소 Hha I 과 HpyCH4IV를 이용한 밴드 패턴 분석을 통해 각각 산백향과 설백향을 다른 균주들과 구분하여 구별성을 확보할 수 있었다. 본 연구에서 개발된 CAPS 마커는 표고의 품종들 간에 유전적 다양성을 부여함으로써, 품종을 보호할 수 있는 분자생물학적 근거가 될 수 있다. 이로써 향후 유전자원에 대한 국가간 분쟁을 미연에 방지할 수 있을 것이다.

• The Plant Pathology Journal
• /
• 제37권6호
• /
• pp.619-631
• /
• 2021

Alfalfa mosaic virus (AMV), an economically important pathogen, is present worldwide with a very wide host range. This work reports for the first time the infection of Vinca minor and Wisteria sinensis with AMV using RNA sequencing and reverse transcription polymerase chain reaction confirmation. De novo assembly and annotating of contigs revealed that RNA1, RNA2, and RNA3 genomic fragments consist of 3,690, 2,636, and 2,057 nucleotides (nt) for IR-VM and 3,690, 2,594, and 2,057 nt for IR-WS. RNA1 and RNA3 segments of IR-VM and IR-WS closely resembled those of the Chinese isolate HZ, with 99.23-99.26% and 98.04-98.09% nt identity, respectively. Their RNA2 resembled that of Canadian isolate CaM and American isolate OH-2-2017, with 97.96-98.07% nt identity. The P2 gene revealed more nucleotide diversity compared with other genes. Genes in the AMV genome were under dominant negative selection during evolution, and the P1 and coat protein (CP) proteins were subject to the strongest and weakest purifying selection, respectively. In the population genetic analysis based on the CP gene sequences, all 107 AMV isolates fell into two main clades (A, B) and isolates of clade A were further divided into three groups with significant subpopulation differentiation. The results indicated moderate genetic variation within and no clear geographic or genetic structure between the studied populations, implying moderate gene flow can play an important role in differentiation and distribution of genetic diversity among populations. Several factors have shaped the genetic structure and diversity of AMV: selection, recombination/reassortment, gene flow, and random processes such as founder effects.