• Journal of Microbiology and Biotechnology
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• 제25권10호
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• pp.1599-1605
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• 2015

The development of rapid and efficient genome sequencing methods has enabled us to study the evolutionary background of bacterial genetic information. Here, we present comparative genomic analysis of 17 Streptomyces species, for which the genome has been completely sequenced, using the pan-genome approach. The analysis revealed that 34,592 ortholog clusters constituted the pan-genome of these Streptomyces species, including 2,018 in the core genome, 11,743 in the dispensable genome, and 20,831 in the unique genome. The core genome was converged to a smaller number of genes than reported previously, with 3,096 gene families. Functional enrichment analysis showed that genes involved in transcription were most abundant in the Streptomyces pan-genome. Finally, we investigated core genes for the sigma factors, mycothiol biosynthesis pathway, and secondary metabolism pathways; our data showed that many genes involved in stress response and morphological differentiation were commonly expressed in Streptomyces species. Elucidation of the core genome offers a basis for understanding the functional evolution of Streptomyces species and provides insights into target selection for the construction of industrial strains.

• Journal of Microbiology and Biotechnology
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• 제30권3호
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• pp.341-351
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• 2020

To shed light on the genetic differences among food-originated coagulase-negative Staphylococcus (CNS), we performed pan-genome analysis of five species: Staphylococcus carnosus (two strains), Staphylococcus equorum (two strains), Staphylococcus succinus (three strains), Staphylococcus xylosus (two strains), and Staphylococcus saprophyticus (one strain). The pan-genome size increases with each new strain and currently holds about 4,500 genes from 10 genomes. Specific genes were shown to be strain dependent but not species dependent. Most specific genes were of unknown function or encoded restriction-modification enzymes, transposases, or prophages. Our results indicate that unique genes have been acquired or lost by convergent evolution within individual strains.

• 미생물학회지
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• 제51권4호
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• pp.329-337
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• 2015

Nitrosomonadales 목에서 속하는 균주 중 현재 유전체 서열이 알려진 모든 유전체(N=10)를 이용하여 범유전체 및 핵심유전체 분석을 수행한 결과, 각각 9,808개와 908개 유전자클러스터를 포함하는 것을 확인하였다. Betaproteobacteria의 다른 목의 참조군들과 비교를 통하여 범유전체와 핵심유전체의 크기에 유전체의 수와 집단 내의 유전체들의 차이가 영향을 미치는 것을 확인하였다. Nitrosomonas 속과 Nitrosospira 속의 범유전체는 7,180개와 4,586개, 핵심유전체는 1,092개와 1,600로로 각각 측정되어 Nitrosospira 속의 동질성이 더 높은 것을 확인하였다. Nitrosomonadales 목의 범유전체와 핵심유전체의 크기에 Nitrosomonas 속이 대부분의 영향을 미치는 것을 확인하였다. COG 분석을 통하여 핵심유전체의 크기에는 J (translation, ribosomal structure and biogenesis) 범주가 가장 큰 비율(9.7-21.0%)을 차지하며, 유전체 사이의 유전적 거리가 먼 집단일수록 그 비율이 높아지는 것을 확인하였다. 범유전체의 크기에는 "-" (unclassified) 범주가 34-51%의 높은 비율을 차지하고 있을 정도로 큰 영향을 미치는 것을 확인하였다. 총 97개의 유전자 클러스터가 참조군에는 없고 Nitrosomonadales에만 존재하는 것을 확인하였다. 이들 클러스터들은 Nitrosomonadales을 특징 지우는 유전자들인 ammonia monooxygenase의 유전자인 amoA와 amoB와 그와 관련 있는 amoE와 amoD들을 포함하는 반면에 unclassified 유전자들도 상당량(16-45%)을 포함하고 있다. 이러한 유전자 클러스터는 Nitrosomonadales의 유전적 특이성을 밝히는 데 중요한 역할을 할 것이다.

• 한국미생물·생명공학회지
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• 제46권2호
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• pp.162-170
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• 2018

Non-typhoidal Salmonella is one of the main pathogens causing food-borne illness in humans, with up to 20% of cases resulting from consumption of pork products. Over the gastroenteritis signs, multidrug resistant Salmonella has arisen. In this study, pan-susceptible phenotypic strains of Salmonella enterica serotype Weltevreden recovered from pig production chain in Chiang Mai, Thailand during 2012-2014 were chosen for analysis. The aim of this study was to use whole genome sequencing (WGS) data with an emphasis on antimicrobial resistance gene investigation to assess their pathogenic potential and genetic diversity determination based on whole genome Multilocus Sequence Typing (wgMLST) to expand epidemiological knowledge and to provide additional guidance for disease control. Analyis using ResFinder 3.0 for WGS database tracing found that one of pan-susceptible phenotypic strain carried five classes of resistance genes: aminoglycoside, beta-lactam, phenicol, sulfonamide, and tetracycline associated genes. Twenty four and 36 loci differences were detected by core genome Multilocus Sequence Typing (cgMLST) and pan genome Multilocus Sequence Typing (pgMLST), respectively, in two matching strains (44/13 vs A543057 and A543056 vs 204/13) initially assigned by conventional MLST and Pulsed-field Gel Electrophoresis (PFGE). One hundread percent discriminant ability can be achieved using the wgMLST technique. WGS is currently the ultimate molecular technique for various in-depth studies. As the findings stated above, a new of "gold standard typing method era" for routine works in genome study is being set.

• The Plant Pathology Journal
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• 제38권2호
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• pp.167-174
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• 2022

Pseudomonas amygdali is a hemibiotrophic phytopathogen that causes disease in woody and herbaceous plants. Complete genomes of four P. amygdali pathovars were comparatively analyzed to decipher the impact of genomic diversity on host colonization. The pan-genome indicated that 3,928 core genes are conserved among pathovars, while 504-1,009 are unique to specific pathovars. The unique genome contained many mobile elements and exhibited a functional distribution different from the core genome. Genes involved in O-antigen biosynthesis and antimicrobial peptide resistance were significantly enriched for adaptation to hostile environments. While the type III secretion system was distributed in the core genome, unique genomes revealed a different organization of secretion systems as follows: type I in pv. tabaci, type II in pv. japonicus, type IV in pv. morsprunorum, and type VI in pv. lachrymans. These findings provide genetic insight into the dynamic interactions of the bacteria with plant hosts.

• Journal of Microbiology and Biotechnology
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• 제31권4호
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• pp.601-609
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• 2021

Erythrobacter species are extensively studied marine bacteria that produce various carotenoids. Due to their photoheterotrophic ability, it has been suggested that they play a crucial role in marine ecosystems. It is essential to identify the genome sequence and the genes of the species to predict their role in the marine ecosystem. In this study, we report the complete genome sequence of the marine bacterium Erythrobacter sp. 3-20A1M. The genome size was 3.1 Mbp and its GC content was 64.8%. In total, 2998 genetic features were annotated, of which 2882 were annotated as functional coding genes. Using the genetic information of Erythrobacter sp. 3-20A1M, we performed pan-genome analysis with other Erythrobacter species. This revealed highly conserved secondary metabolite biosynthesis-related COG functions across Erythrobacter species. Through subsequent secondary metabolite biosynthetic gene cluster prediction and KEGG analysis, the carotenoid biosynthetic pathway was proven conserved in all Erythrobacter species, except for the spheroidene and spirilloxanthin pathways, which are only found in photosynthetic Erythrobacter species. The presence of virulence genes, especially the plant-algae cell wall degrading genes, revealed that Erythrobacter sp. 3-20A1M is a potential marine plant-algae scavenger.

• 과학기술학연구
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• 제19권2호
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• pp.117-167
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• 2019

인간 유전체 프로젝트의 초안 발표 이후 여러 한국인 유전체 프로젝트들이 추진되었다. 그 결과 등장한 한국인 유전체를 둘러싼 흥미로운 담론 중 하나는 "한국인 유전체" 서열 분석을 통해 "아시아인 맞춤의학"을 구현할 수 있다는 주장이다. 본 논문은 이를 한국 유전체 학자들이 자국민에 대한 유전체 자료를 상업화하려는 노력 가운데 발전시킨 전략으로 인지하고, 이 "아시아인 건강을 위한 한국인 게놈" 전략이 출현하게 된 배경을 역사적으로 검토한다. 이 글은 한국 유전체 프로젝트들의 전략이 탈식민 국가들에서 빈번하게 발견되는 "유전체 주권"(genome sovereignty) 정책이 2000년대 초반 이후 한국에서 주요 정책 의제로 부상한 아시아 지역주의와 결합하여 등장한 산물이라고 주장한다. 이를 통해 이 연구는 그간 범아시아 SNP 컨소시엄(Pan-Asian Single Nucleotide Polymorphism Consortium)을 중심으로 논의된 유전체학과 아시아인의 구성에 관한 과학기술학 연구가 국소적인 아시아인 관념과 아시아 지역주의를 가진 싱가포르의 경험을 지나치게 일반화해왔음을 지적한다. 이와 함께 한국 유전체학 거버넌스에서 과학기술학자들이 맡을 수 있는 역할에 대해서도 고민해 볼 기회를 제공할 것이다.

• Genomics & Informatics
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• 제12권1호
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• pp.42-47
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• 2014

Asian populations contain a variety of ethnic groups that have ethnically specific genetic differences. Ethnic variants may be highly relevant in disease and human differentiation studies. Here, we identified ethnically specific variants and then investigated their distribution across Asian ethnic groups. We obtained 58,960 Pan-Asian single nucleotide polymorphisms of 1,953 individuals from 72 ethnic groups of 11 Asian countries. We selected 9,306 ethnic variant single nucleotide polymorphisms (ESNPs) and 5,167 ethnic variant copy number polymorphisms (ECNPs) using the nearest shrunken centroid method. We analyzed ESNPs and ECNPs in 3 hierarchical levels: superpopulation, subpopulation, and ethnic population. We also identified ESNP- and ECNP-related genes and their features. This study represents the first attempt to identify Asian ESNP and ECNP markers, which can be used to identify genetic differences and predict disease susceptibility and drug effectiveness in Asian ethnic populations.

• Genomics & Informatics
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• 제17권4호
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• pp.43.1-43.5
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• 2019

Lactobacillus acidophilus UBLA-34, L. paracasei UBLPC-35, L. plantarum UBLP-40, and L. reuteri UBLRU-87 were isolated from different varieties of fermented foods. To determine the probiotic safety at the strain level, the whole genome of the respective strains was sequenced, assembled, and characterized. Both the core-genome and pan-genome phylogeny showed that L. reuteri was closest to L. plantarum than to L. acidophilus, which was closest to L. paracasei. The genomic analysis of all the strains confirmed the absence of genes encoding putative virulence factors, antibiotic resistance, and the plasmids.

• Journal of Animal Science and Technology
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• 제63권6호
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• pp.1411-1422
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• 2021

Lactobacillus acidophilus is a gram-positive, microaerophilic, and acidophilic bacterial species. L. acidophilus strains in the gastrointestinal tracts of humans and other animals have been profiled, but strains found in the canine gut have not been studied yet. Our study helps in understanding the genetic features of the L. acidophilus C5 strain found in the canine gut, determining its adaptive features evolved to survive in the canine gut environment, and in elucidating its probiotic functions. To examine the canine L. acidophilus C5 genome, we isolated the C5 strain from a Korean dog and sequenced it using PacBio SMRT sequencing technology. A comparative genomic approach was used to assess genetic relationships between C5 and six other strains and study the distinguishing features related to different hosts. We found that most genes in the C5 strain were related to carbohydrate transport and metabolism. The pan-genome of seven L. acidophilus strains contained 2,254 gene families, and the core genome contained 1,726 gene families. The phylogenetic tree of the core genes in the canine L. acidophilus C5 strain was very close to that of two strains (DSM20079 and NCFM) from humans. We identified 30 evolutionarily accelerated genes in the L. acidophilus C5 strain in the ratio of non-synonymous to synonymous substitutions (dN/dS) analysis. Five of these thirty genes were associated with carbohydrate transport and metabolism. This study provides insights into genetic features and adaptations of the L. acidophilus C5 strain to survive the canine intestinal environment. It also suggests that the evolution of the L. acidophilus genome is closely related to the host's evolutionary adaptation process.