• 제목/요약/키워드: Corynebacterium glutamicum

검색결과 141건 처리시간 0.087초

Studies on Intergeneric Protoplast fusion and L-Lysine Productivity

  • 이인선;조정일
    • 동아시아식생활학회지
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    • 제5권1호
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    • pp.93-99
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    • 1995
  • For the improvement of the L-lysine productivity of Brevibacterium flavum and Corynebacterium glutamicum, fusants were induced by interspecific protoplast fusion of Bacillus subtilis with C. glutamicum and B. flavum. The following results were obtained through protoplast formation of strains condition of protoplast fusion, characteristics of the fusants, and the productivity of lysine form starch. B. flavum BF-5 and C. glutamicum protoplasts were made by the treatment of 0.3unit/$m\ell$ of penicillin G at the early stationary growth phase for 2 hours followed by incubation with 10mg/$m\ell$ of lysozyme at 37$^{\circ}C$ for 120 min. When a mixture of the protoplast was treated with 30% PEG(M.W.6,000) solution containing 50mM CaCl2 at optimal conditions, the intergeneric fusion frequency between protoplasts of C. glutamicum CG-2 and B. subtilis BD 224 was 7.1${\times}$105. The genetic properties on the L-lysine producing fusants were compared with those of parental strains. As a results, the intergeneric fusants were completed in each auxotrophic requirement, resistances for S-(2-amino-ethyl)-L-cysteine and kanamycine were confirmed. And one of fusants selected, FBB-41 were found to be genetically stable fusants. The aspartokinase activity of FBB-41 strain increased than that of the parent strain.

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Towards Methionine Overproduction in Corynebacterium glutamicum - Methanethiol and Dimethyldisulfide as Reduced Sulfur Sources

  • Bolten, Christoph J.;Schroder, Hartwig;Dickschat, Jeroen;Wittmann, Christoph
    • Journal of Microbiology and Biotechnology
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    • 제20권8호
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    • pp.1196-1203
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    • 2010
  • In the present work, methanethiol and dimethyldisulfide were investigated as sulfur sources for methionine synthesis in Corynebacterium glutamicum. In silico pathway analysis predicted a high methionine yield for these reduced compounds, provided that they could be utilized. Wild-type cells were able to grow on both methanethiol and dimethyldisulfide as sole sulfur sources. Isotope labeling studies with mutant strains, exhibiting targeted modification of methionine biosynthesis, gave detailed insight into the underlying pathways involved in the assimilation of methanethiol and dimethyldisulfide. Both sulfur compounds are incorporated as an entire molecule, adding the terminal S-$CH_3$ group to O-acetylhomoserine. In this reaction, methionine is directly formed. MetY (O-acetylhomoserine sulfhydrylase) was identified as the enzyme catalyzing the reaction. The deletion of metY resulted in methionine auxotrophic strains grown on methanethiol or dimethyldisulfide as sole sulfur sources. Plasmid-based overexpression of metY in the ${\Delta}$metY background restored the capacity to grow on methanethiol or dimethyldisulfide as sole sulfur sources. In vitro studies with the C. glutamicum wild type revealed a relatively low activity of MetY for methanethiol (63 mU/mg) and dimethyldisulfide (61 mU/mg). Overexpression of metY increased the in vitro activity to 1,780 mU/mg and was beneficial for methionine production, since the intracellular methionine pool was increased 2-fold in the engineered strain. This positive effect was limited by a depletion of the metY substrate O-acetylhomoserine, suggesting a need for further metabolic engineering targets towards competitive production strains.

Triclosan과 죽염을 함유한 바디워시의 액취 등에 미치는 효과에 대한 연구 (The Effect of Body Wash Containing Triclosan and Bamboo Salt on Axillary Malodor)

  • 노석선;윤우식;정지영;유형욱;황동성;최승만;이정래;강상진;장석윤
    • 대한화장품학회지
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    • 제35권3호
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    • pp.219-228
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    • 2009
  • 1.0 wt% triclosan과 0.4 wt% 죽염을 함유한 바디워시의 액취 등에 미치는 효과에 대한 연구를 위하여 in vitro 항균시험 및 무작위 배정, 이중맹검, 교차설계로 진행한 임상시험을 실시하였다. 1.0 wt% triclosan과 0.4 wt% 죽염을 함유한 바디워시는 Corynebacterium glutamicum, Corynebacterium xerosis, Corynebacterium jeikeium를 균주로 한 in vitro 항균 실험에서 모두 우수한 항균 효과가 있었다. 1.0 wt% triclosan과 0.4 wt% 죽염을 함유한 바디워시는 액취를 전반적으로 유의성 있게 감소시켰고 그 효과는 최소 9 h 동안 지속되었다. 1.0 wt% triclosan과 0.4 wt% 죽염을 함유한 바디워시는 액와 균수를 유의성 있게 감소시켰고 그 효과는 최소 9 h 동안 지속되었다. 임상시험 기간 동안 피시험자 전체에서 이상반응 증상은 나타나지 않았다. 결론적으로 1.0 wt% triclosan과 0.4 wt% 죽염을 함유한 바디워시는 액취에 대한 감소효과와 피부 안전성이 우수하였다.

Coryneform bacteria의 原形質體 形成, 再生 및 融合에 관한 硏究 (The protoplast formation, regeneration and fusion of coryneform bacteria)

  • 신명교;이세영;임번삼;전문진
    • 미생물학회지
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    • 제22권3호
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    • pp.175-181
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    • 1984
  • In order to develope a protoplast fusion system for industrial coryneform bacteria, the optimum conditions for the formation and regeneration of progoplast were examined for Brevibacterium flavum and Corynebacterium glutamicum and the protoplast fusion was performed. For the formation of the protoplast of B. flavum and C. glutamicum, the optimum time for penicillin G. treatment to obtain protoplast was mid-exponential growth phase ($O.D_{580}=0.6-0.8,\;8.0{\times}10^7-1.0{\times}10^8cell/ml$). At the optimum conditions (0.3units/ml penicillin G and $400{\mu}g/ml$ lysoyme for treatement), frequencies of protoplast formation and protoplast regeneration were 99% and 25%, respectively. Protoplast regeneration frequency was highest under the optimum conditions for the protoplast formation. Addition of 25mM $Mg^{2+}\;and\;50mM\;Ca^{2+}$ to the regeneration medium further increased the regeneration frequencies. The protoplast fusion frequencies of B. flavum and C. glutamicum in intraspecies fusion were $1.0{\times}10^{-8}\;and\;7.8{\times}10^{-4}$, of the regenerated protoplast respectively, when 33% of PEG (polythylene glycol) 6,000 was used as the fusing agent.

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