• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2005년도 생물공학의 동향(XVII)
• /
• pp.1002-1002
• /
• 2005

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2005년도 생물공학의 동향(XVII)
• /
• pp.962-963
• /
• 2005

• 한국생물공학회:학술대회논문집
• /
• 한국생물공학회 2005년도 생물공학의 동향(XVII)
• /
• pp.490-490
• /
• 2005

• 한국동물학회:학술대회논문집
• /
• 한국동물학회 2000년도 한국생물과학협회 학술발표대회
• /
• pp.286.3-287
• /
• 2000

No Abstract, See Full Text

• 농약과학회지
• /
• 제12권1호
• /
• pp.97-101
• /
• 2008

소나무재선충에 대한 살선충 활성을 나타내는 방선균의 탐색 및 동정을 위하여 2000여개의 방선균배양액 라이브러리로부터 살선충 활성을 탐색하였다. 현재 소나무재선충에 대한 생물학적 방제제로 사용되고 있는 Streptomyces avermitilis 균주 배양액의 살선충 활성과 비교하여 선발한 결과, 강력한 살선충 활성을 나타내는 균주 AW050027을 균주를 최종 선발하였다. 선발군주에 대하여 형태학적, 배양학적, 생리학적 특성 분석 및 분자계통분류학적 분석을 한 결과 선발군주는 Micromonospora coriariae $NAR01^T$ 균주와 98.9%의 상동성을 가진 균주로 동정되었다.

• Journal of Microbiology and Biotechnology
• /
• 제25권11호
• /
• pp.1787-1795
• /
• 2015

The transition from primary to secondary metabolism in antibiotic-producing Streptomyces correlates with expression of genes involved in stress responses. Consequently, regulatory pathways that regulate specific stress responses are potential targets to manipulate to increase antibiotic titers. In this study, genes encoding key proteins involved in regulation of the osmotic stress response in Streptomyces avermitilis, the industrial producer of avermectins, are investigated as targets. Disruption of either osaB_Sa, encoding a response regulator protein, or osaC_Sa, encoding a multidomain regulator of the alternative sigma factor SigB, led to increased production of both oligomycin, by up to 200%, and avermectin, by up to 37%. The mutations also conditionally affected morphological development; under osmotic stress, the mutants were unable to erect an aerial mycelium. In addition, we demonstrate the delivery of DNA into a streptomycete using biolistics. The data reveal that information on stress regulatory responses can be integrated in rational strain improvement to improve yields of bioactive secondary metabolites.

• Journal of Microbiology and Biotechnology
• /
• 제18권7호
• /
• pp.1216-1220
• /
• 2008

Sequence analysis of the metabolically rich genome of Streptomyces peucetius ATCC 27952 revealed a 2,199 bp sesquiterpene alcohol (germacradienol) synthase-encoding gene from the germacradienol synthase/terpene cyclase gene cluster. The gene was named spterp13, and its putative function is as a germacradienol synthase/terpene cyclase. The amino acid sequence of Spterp13 shows 66% identity with SAV2163 (GeoA) from S. avermitilis MA4680 and 65% identity with SCO6073 from S. coelicolor A3(2), which produces germacradienol/geosmin. The full-length recombinant protein was heterologously expressed as a his-tagged fusion protein in Escherichia coli, purified, and shown to catalyze the $Mg^{2+}$-dependent conversion of farnesyl diphosphate to the germacradienol, which was verified by gas chromatography/mass spectrometry.

• 한국미생물·생명공학회지
• /
• 제38권4호
• /
• pp.475-480
• /
• 2010

Actinomycetes are Gram-positive soil bacteria and one of the most important industrial microorganisms due to superior biosynthetic capabilities of many valuable secondary metabolites as well as production of various valuable bioconversion enzymes. Among them are cytochrome P450 hydroxylase (CYP), which are hemoproteins encoded by a super family of genes, are universally distributed in most of the organisms from all biological kingdoms. Actinomycetes are a rich source of soluble CYP enzymes, which play critical roles in the bioactivation and detoxification of a wide variety of metabolite biosynthesis and xenobiotic transformation. Cyclosporin A (CyA), one of the most commonly-prescribed immunosuppressive drugs, was previously reported to be hydroxylated at the position of 4th N-methyl leucine by a rare actinomycetes called Sebekia benihana, leading to display different biological activity spectrum such as loss of immunosuppressive activities yet retaining hair growth-stimulating side effect. In order to improve this regio-selective CyA hydroxylation in S. benihana, previously-identified several secondary metabolite up-regulatory genes from Streptomyces coelicolor and S. avermitilis were heterologously overexpressed in S. benihana using an $ermE^*$ promoter-containing Streptomyces integrative expression vector. Among tested, SCO4967 encoding a conserved hypothetical protein significantly stimulated region-specific CyA hydroxylation in S. benihana, implying that some common regulatory systems functioning in both biosynthesis and bioconversion of secondary metabolite might be present in different actinomycetes species.

• Journal of Microbiology and Biotechnology
• /
• 제20권12호
• /
• pp.1689-1695
• /
• 2010

Pantothenate kinase (PanK) catalyzes the first step in the biosynthesis of the essential and ubiquitous cofactor coenzyme A (CoA) in all organisms. Here, we report the identification, cloning, and characterization of panK-sp from Streptomyces peucetius ATCC 27952. The gene encoded a protein of 332 amino acids with a calculated molecular mass of 36.8 kDa and high homology with PanK from S. avermitilis and S. coelicolor A3(2). To elucidate the putative function of PanK-sp, it was cloned into pET32a(+) to construct pPKSP32, and the PanK-sp was then expressed in E. coli BL21(DE3) as a His-tag fusion protein and purified by immobilized metal affinity chromatography. The enzyme assay of PanK-sp was carried out as a coupling assay. The gradual decrease in NADH concentration with time clearly indicated the phosphorylating activity of PanK-sp. Furthermore, the ca. 1.4-fold increase of DXR and the ca. 1.5-fold increase of actinorhodin by in vivo overexpression of panK-sp, constructed in pIBR25 under the control of a strong $ermE^*$ promoter, established its positive role in secondary metabolite production from S. peucetius and S. coelicolor, respectively.

• 미생물학회지
• /
• 제41권4호
• /
• pp.255-261
• /
• 2005

Streptomyces griseus trypsin(SGT)을 코드하는 sprT 유전자를 포함하여 약 6.7 kb의 DNA 단편을 Streptomyces griseus ATCC 10137의 염색체 DNA로부터 클로닝 하여 염기서열을 결정하였다. 염기서열 분석 결과, 염색체 DNA를 EcoRI-HindIII 제한효소로 완전 분해하여 클로닝한 약6.7 kb의 단편에는 sprT유전자를 포함하여 총6개의 완전한 ORF (open reading frame)와 1개의 불완전한 ORF가 존재하는 것으로 밝혀졌으며, 순서대로 ORF1, SGT, ORF2, ORF3, ORF4, ORF5, ORF6로 명명하였다. 예상 단백질의 아미노산 서열 분석 결과, ORF1은 oxidoreductase, ORF3는 ArsR family의 transcription regulator, ORF4는 Listeria monocytogenes의 LPXTG motif를 갖는 peptidoglycan bound protein, ORF5는 transmembrane helix를 갖는 막단백질, ORF6는 Streptomyces avermitilis에서 보고된 lipoprotein과 높은 상동성을 보였으며, ORF2는 기능을 예측 할 수 없었다. 이와 같은 분석결과, sprT 유전자 주위에는 세포막이나 세포벽 구성성분을 코드하는 유전자가 존재하고 있으며, 따라서 SGT Pretense는 이러한 세포막 또는 세포벽 합성이나 분해과정에서 어떤 기능을 담당할 가능성 이 있는 것으로 추측되었다.