• The Plant Pathology Journal
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• 제36권5호
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• pp.491-496
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• 2020

An understanding of the contribution of secondary metabolites (SMs) to the antagonistic and biocontrol activities of bacterial biocontrol agents serves to improve biocontrol potential of the strain. In this study, to evaluate the contribution of each SM produced by Pseudomonas fluorescens NBC275 (Pf275) to its antifungal and biocontrol activity, we combined in silico analysis of the genome with our previous study of transposon (Tn) mutants. Thirteen Tn mutants, which belonged to 6 biosynthetic gene clusters (BGCs) of a total 14 BGCs predicted by the antiSMASH tool were identified by the reduction of antifungal activity. The biocontrol performance of Pf275 was significantly dependent on 2,4-diacetylphloroglucinol and pyoverdine. The clusters that encode for arylpolyene and an unidentified small linear lipopeptide influenced antifungal and biocontrol activities. To our knowledge, our study identified the contribution of SMs, such as a small linear lipopeptide and arylpolyene, to biocontrol efficacy for the first time.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.830-839
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• 2007

Pradimicins are potent antifungal antibiotics having an unusual dihydrobenzo[$\alpha$]naphthacenequinone aglycone substituted with D-alanine and sugars. Pradimicins are polyketide antibiotics produced by Actinomadura hibisca P157-2. The gene cluster involved in the biosynthesis of pradimicins was cloned and sequenced. The pradimicin gene cluster was localized to a 39-kb DNA segment and its involvement in the biosynthesis of pradimicin was proven by gene inactivation of prmA and prmB(ketosynthases $\alpha\;and\;\beta$). The pradimicin gene cluster consists of 28 open reading frames(ORFs), encoding a type II polyketide synthase(PKS), the enzymes involved in sugar biosynthesis and tailoring enzymes as well as two resistance proteins. The deduced proteins showed strong similarities to the previously validated gene clusters of angucyclic polyketides such as rubromycin, griseorhodin, and fredericamycin. From the pradimicin gene cluster, prmP3 encoding a component of the acetyl-CoA carboxylase complex was disrupted. The production levels of pradimicins of the resulting mutants decreased to 62% of the level produced by the wild-type strain, which indicate that the acetyl-CoA carboxylase gene would have a significant role in the production of pradimicins through supplying the extender unit precursor, malonyl-CoA.

• Journal of Microbiology and Biotechnology
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• 제18권8호
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• pp.1416-1422
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• 2008

Epothilone and its analogs are a potent new class of anticancer compounds produced by myxobacteria. Thus, in an effort to identify new myxobacterial strains producing epothilone and its analogs, cellulose-degrading myxobacteria were isolated from Korean soils, and 13 strains carrying epothilone biosynthetic gene homologs were screened using a polymerase chain reaction. A migration assay revealed that Sorangium cellulosum KYC3013, 3016, 3017, and 3018 all produced microtubule-stabilizing compounds, and an LC-MS/MS analysis showed that S. cellulosum KYC3013 synthesized epothilone A.

• Mycobiology
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• 제50권4호
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• pp.254-257
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• 2022

Wolfiporia cocos is a wood-decay brown rot fungus belonging to the family Polyporaceae. While the fungus grows, the sclerotium body of the strain, dubbed Bokryeong in Korean, is formed around the roots of conifer trees. The dried sclerotium has been widely used as a key component of many medicinal recipes in East Asia. Wolfiporia cocos strain KMCC03342 is the reference strain registered and maintained by the Korea Seed and Variety Service for commercial uses. Here, we present the first draft genome sequence of W. cocos KMCC03342 using a hybrid assembly technique combining both short- and long-read sequences. The genome has a total length of 55.5 Mb comprised of 343 contigs with N50 of 332 kb and 95.8% BUSCO completeness. The GC ratio was 52.2%. We predicted 14,296 protein-coding gene models based on ab initio gene prediction and evidence-based annotation procedure using RNAseq data. The annotated genome was predicted to have 19 terpene biosynthesis gene clusters, which was the same number as the previously sequenced W. cocos strain MD-104 genome but higher than Chinese W. cocos strains. The genome sequence and the predicted gene clusters allow us to study biosynthetic pathways for the active ingredients of W. cocos.

• 미생물학회지
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• 제55권3호
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• pp.303-305
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• 2019

섬 해안가 토양에서 방선균주 Gordonia sp. MMS17-SY073를 분리하여 유전체 분석을 실시하였고, 그 결과 5,962,176 염기쌍 및 67.4%의 G + C 함량으로 이루어진 유전체 정보를 확보하였다. 유전정보 분석 결과 총 5,201개 단백질 지정 유전자, 6개 rRNA 유전자 및 45개 tRNA 유전자를 확인하였다. MMS17-SY073 균주는 16S rRNA 유전자를 이용한 분석 결과 분류학적으로 Gordonia soli의 표준균주와 가장 가까웠으며 그 유사도는 98.5%로 나타났다. MMS17-SY073 균주는 non-ribosomal peptide synthetase 유형을 비롯한 다수의 이차대사산물 생합성 유전자를 보유하고 있는 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제25권10호
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• pp.1648-1652
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• 2015

Azaphilone polyketides are synthesized by iterative non-reducing fungal polyketide synthases (NR-fPKSs) with a C-terminus reductive domain (-R). Several azaphilone biosynthetic gene clusters contain a putative serine hydrolase gene; the Monascus azaphilone pigment (MAzP) gene cluster harbors mppD. The MAzP productivity was significantly reduced by a knockout of mppD, and the MAzP NR-fPKS-R gene (MpPKS5) generated its product in yeast only when co-expressed with mppD. Site-directed mutations of mppD for conserved Ser/Asp/His residues abolished the product formation from the MpPKS5/mppD co-expression. MppD and its homologs are thus proposed as a new protein factor involved in the product formation of NR-fPKS-R.

• 한국미생물·생명공학회지
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• 제37권4호
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• pp.316-321
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• 2009

국내 토양으로부터 Chondromyces crocatus KYC2823을 순수 분리하고, 또 다른 5균주를 동반 세균이 함께 존재하는 상태로 분리하였다. 균주 KYC2823은 경북 청도군에서 채취한 토양시료에서 분리하였으며, 자실체 형태와 특이한 향의 발산을 포함한 여러 특성이 전형적인 C. crocatus임을 보였다. 이에 더해, 16S rDNA 염기서열이 C. crocatus의 새 표준균주로 제안된 Cm c5과 99.8% 유사하였다. 한편, PCR을 이용한 polyketide 생합성 유전자 조각의 클로닝 및 분석은 균주 KYC2823이 전자전달계 저해물질인 ajudazol과 actin cytoskeleton의 기능에 영향을 미치는 물질인 chondramide의 생합성 유전자, 그리고 아직까지 클로닝되지 않은 polyketide 계열 물질의 생합성 유전자를 가지고 있음을 보여주었다.

• Journal of Applied Biological Chemistry
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• 제62권2호
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• pp.157-165
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• 2019

Di- and tri-methylation of lysine 4 on histone H3 (H3K4me2 and H3K4me3, respectively) are epigenetic markers of active genes. Complex associated with Set1 (COMPASS) mediates these H3K4 methylations. The involvement of COMPASS activity in secondary metabolite (SM) biosynthesis was first demonstrated with an Aspergillus nidulans cclA knockout mutant. The cclA knockout induced the transcription of two cryptic SM biosynthetic gene clusters, leading to the production of the cognate SM. Monascus spp. are filamentous fungi that have been used for food fermentation in eastern Asia, and the pigment Monascus azaphione (MAz) is their main SM. Monascus highly produces MAz, implying that the cognate biosynthetic genes are highly active in transcription. In the present study, we examined how COMPASS activity modulates MAz biosynthesis by inactivating Monascus purpureus cclA (Mp-cclA) and swd1 (Mp-swd1). For both ${\Delta}Mp-cclA$ and ${\Delta}Mp-swd1$, a reduction in MAz production, accompanied by an abated cell growth, was observed. Suppression of MAz production was more effective in an agar culture than in the submerged liquid culture. The fidelity of the ${\Delta}Mp-swd1$ phenotypes was verified by restoring the WT-like phenotypes in a reversion recombinant mutant, namely, trpCp: Mp-swd1, that was generated from the ${\Delta}Mp-swd1$ mutant. Real-time quantitative Polymerase chain reaction analysis indicated that the transcription of MAz biosynthetic genes was repressed in the ${\Delta}Mp-swd1$ mutant. This study demonstrated that MAz biosynthesis is under the control of COMPASS activity and that the extent of this regulation is dependent on growth conditions.

• 한국미생물·생명공학회지
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• 제51권3호
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• pp.325-327
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• 2023

This paper presents the complete genome sequence of a novel marine actinomycete, Streptomyces sp. MMBL 11-1. The genome of Streptomyces sp. MMBL 11-1 was obtained through next-generation sequencing using the PacBio Sequel system and Illumina platform provided by Macrogen, Korea. The assembled genome consists of five contigs, with a total length of 8,496,900 bp and a G+C content of 71.6%. The genome harbors multiple biosynthetic gene clusters (BGCs) associated with producing microbial natural products (MNPs). The comprehensive genomic information of this type of strain will serve as a valuable resource for identifying other marine actinomycetes strains.

• Journal of Acupuncture Research
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• 제37권2호
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• pp.128-135
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• 2020

Background: Classical acupuncture is being used in the treatment of rheumatoid arthritis (RA). To explore the biological response to acupuncture, a network-based analysis was performed on gene expression data collected from an animal model of RA treated with acupuncture. Methods: Gene expression data were obtained from published microarray studies on blood samples from rats with collagen induced arthritis (CIA) and non-CIA rats, both treated with manual acupuncture. The weighted gene co-expression network analysis was performed to identify gene clusters expressed in association with acupuncture treatment time and RA status. Gene ontology and pathway analyses were applied for functional annotation and network visualization. Results: A cluster of 347 genes were identified that differentially downregulated expression in association with acupuncture treatment over time; specifically in rats with CIA with module-RA correlation at 1 hour after acupuncture (-0.27; p < 0.001) and at 34 days after acupuncture (-0.33; p < 0.001). Functional annotation showed highly significant enrichment of porphyrin-containing compound biosynthetic processes (p < 0.001). The network-based analysis also identified a module of 140 genes differentially expressed between CIA and non-CIA in rats (p < 0.001). This cluster of genes was enriched for antigen processing and presentation of exogenous peptide antigen (p < 0.001). Other functional gene clusters previously reported in earlier studies were also observed. Conclusion: The identified gene expression networks and their hub-genes could help with the understanding of mechanisms involved in the pathogenesis of RA, as well understanding the effects of acupuncture treatment of RA.