• BMB Reports
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• 제28권6호
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• pp.523-526
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• 1995

Administering ${\delta}-aminolevulinic$ acid (ALA) to isolated pea (Pisum sativum L.) chloroplasts resulted in an increase of heme synthesis in the heme branch of the tetrapyrrole pathway. At 0.1 mM ALA, in the presence of 1 mM $FeSO_4$ heme synthesis was stimulated up to 7 fold of that in the absence of $FeSO_4$. N-Methylmesoporphyrin IX (NMMP), a powerful inhibitor of ferrochelatase, inhibited heme synthesis by 95% at one micromolar concentration. The addition of A TP to the chloroplasts caused not only heme synthesis, but Mg-protoporphyrin IX synthesis in the chlorophyll branch of the tetrapyrrole pathway. In the presence of NMMP, however, inhibition of Mg-protoporphyrin IX synthesis was not observed whereas heme synthesis was inhibited completely.

• 미생물학회지
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• 제24권2호
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• pp.98-105
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• 1986

Rhizobium melitoli 102F51에 N-methyl-N'-nitro-N-nitrosoguanidine 및 UV를 처리하여 heme 합성 특성이 다른 세 그룹의 mutant 즉 백색, 적백색 및 적색근류형성 mutant를 선별하여 이들 중 mutant들의 acetylene 환원력, 및 ${\delta}-aminolevulinic$ acid dehydratase (ALAD)를 free living 및 bacteriod 상태하에서 서로 비교하였다. 백색 근류를 형성하는 mutant는 적색 근류형성 mutant에 비하여 acetylene 환원력이 훨씬 낮았으며 ALAS 및 ALAD 활성은 free-living 상태에서는 각 mutant group 사이에서 큰 차이를 보이지 않았으나 bacteriod 상태에서는 백색근류생성 mutant에서 적색 근류형성 mutant group에 비하여 ALAS 및 ALAD 공히 현저히 낮았다. 근류에서 ALAS 활성은 heme 합성양에 비례하여 급진적으로 증가하였으나 ALAD 활성은 plant fraction에서는 감소하는 반면 bacteroid fraction에서는 완만하게 증가하였다.

• Journal of Microbiology and Biotechnology
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• 제23권5호
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• pp.668-673
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• 2013

A recombinant E. coli co-expressing ALA synthase (hemA), NADP-dependent malic enzyme (maeB), and dicarboxylic acid transporter (dctA) was reported to synthesize porphyrin derivatives including iron-containing heme. To enhance the synthesis of bacterial heme, five genes of the porphyrin biosynthetic pathway [pantothenate kinase (coaA), ALA dehydratase (hemB), 1-hydroxymethylbilane synthase (hemC), uroporphyrinogen III synthase (hemD), and uroporphyrinogen III decarboxylase (hemE)] were amplified in the recombinant E. coli co-expressing hemA-maeB-dctA. Pantothenate kinase expression enabled the recombinant E. coli to accumulate intracellular CoA. Intracellular ALA was the most enhanced by uroporphyrinogen III synthase expression, porphobilinogen was the most enhanced by ALA dehydratase expression, uroporphyrin and coproporphyrin were the most enhanced by 1-hydroxymethylbilane synthase expression. The strain co-expressing coaA, hemA, maeB, and dctA produced heme of $0.49{\mu}mol/g$-DCW, which was twice as much from the strain without coaA expression. Further pathway gene amplifications for the porphyrin derivatives are discussed based on the results.

• Journal of Microbiology and Biotechnology
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• 제22권12호
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• pp.1653-1658
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• 2012

We have reported previously that a recombinant Escherichia coli co-expresses aminolevulinic acid (ALA) synthase, an NADP-dependent malic enzyme, and a dicarboxylate transporter-produced heme, an iron-chelated porphyrin, in a succinate-containing complex medium. To develop an industrially plausible process, a chemically defined medium was formulated based on M9 minimal medium. Heme synthesis was enhanced by adding sodium bicarbonate, which strengthened the C4 metabolism required for the precursor metabolite, although a pH change discouraged cell growth. Increasing the medium pH buffering capacity (100mM phosphate buffer) and adding sodium bicarbonate enabled the recombinant E. coli to produce heme at rates 60% greater than those in M9 minimal medium. Adding growth factors (1 mg/l thiamin, 0.01 mg/l biotin, 5 mg/l nicotinic acid, 1 mg/l pantothenic acid, and 1.4 mg/l cobalamin) also induced positive heme production effects at levels twice of heme production in M9-based medium. Porphyrin derivatives and heme were found in the chemically defined medium, and their presence was confirmed by liquid chromatography/mass spectroscopy (LC/MS). The formulated medium allowed for the production of $0.6{\mu}M$ heme, $29{\mu}M$ ALA, $0.07{\mu}M$ coproporphyrin I, $0.21{\mu}M$ coproporphyrin III, and $0.23{\mu}M$ uroporphyrin in a 3 L pH-controlled culture.

• BMB Reports
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• 제34권4호
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• pp.385-389
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• 2001

Insulin-like growth factor binding protein-1 (IGFBP-1) appears to be an important modular of the insulin growth factor (IGF) bioactivity in metabolic disease and chronic hypoxia. Treatment of desferrioxamine (Dfo), cobalt, or nickel in HepG2 cells stimulated the expression of IGFBP1 mRNA as hypoxia. However, the presence of ferric ammonium citrate (FAC) in the 1% $O_2$ decreased the upregulation of the IGFBP-1 mRNA expression. In addition, actinomycin D and cycloheximide abolished the increase in the expression of IGFBP-1 mRNA that was induced by Dfo and transition metals (cobalt and nickel). To obtain further information about the putative oxygen sensor, we postulate that putative heme proteins, responsible for the oxygen-sensing process in HepG2 cells, should be sensitive to hypoada. The mechanism of these upregulations of the IGFBP-1 mRNA expression by Dfo and transition metals was investigated by treatment with 2 mM of 4,6-dioxoheptanoic acid (DHA), an inhibitor of heme biosynthesis. The results showed that 1% $O_2$-, Dfo-, cobalt-, or nickel induced IGFBP-1 mRNA expressions in HepG2 cells were all markedly inhibited when the heme synthesis was blocked by DHA. We suggest that the IGFBP-1 mRNA expression in the HepG2 cell is regulated by 1% $O_2$, Dfo, cobalt, or nickel, implicating the involvement of the putative heme-containing oxygensensing molecule.

• Journal of Microbiology and Biotechnology
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• 제20권4호
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• pp.712-717
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• 2010

Cytochrome P450 enzymes (P450s) are involved in the synthesis of a wide variety of valuable products and in the degradation of numerous toxic compounds. The P450 BM3 (CYP102A1) from Bacillus megaterium was the first P450 discovered to be fused to its redox partner, a mammalian-like diflavin reductase. Here, we report the development of a whole-cell biocatalyst using ice-nucleation protein (Inp) from Pseudomonas syringae to display a hemeand diflavin-containing oxidoreductase, P450 BM3 (a single, 119-kDa polypeptide with domains of both an oxygenase and a reductase) on the surface of Escherichia coli. The surface localization and functionality of the fusion protein containing P450 BM3 were verified by flow cytometry and measurement of enzymatic activities. The results of this study comprise the first report of microbial cell-surface display of a heme- and diflavin-containing enzyme. This system should allow us to select and develop oxidoreductases containing heme and/or flavins into practically useful whole-cell biocatalysts for extensive biotechnological applications, including selective synthesis of new chemicals and pharmaceuticals, bioconversion, bioremediation, live vaccine development, and biochip development.

• Clinical Nutrition Research
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• 제11권4호
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• pp.316-330
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• 2022

Iron plays a role in energy metabolism as a component of vital enzymes and electron transport chains (ETCs) for adenosine triphosphate (ATP) synthesis. The tricarboxylic acid (TCA) cycle and oxidative phosphorylation are crucial in generating ATP in mitochondria. At the mitochondria matrix, heme and iron-sulfur clusters are synthesized. Iron-sulfur cluster is a part of the aconitase in the TCA cycle and a functional or structural component of electron transfer proteins. Heme is the prosthetic group for cytochrome c, a principal component of the respiratory ETC. Regarding fat metabolism, iron regulates mitochondrial fat oxidation and affects the thermogenesis of brown adipose tissue (BAT). Thermogenesis is a process that increases energy expenditure, and BAT is a tissue that generates heat via mitochondrial fuel oxidation. Iron deficiency may impair mitochondrial fuel oxidation by inhibiting iron-containing molecules, leading to decreased energy expenditure. Although it is expected that impaired mitochondrial fuel oxidation may be restored by iron supplementation, its underlying mechanisms have not been clearly identified. Therefore, this review summarizes the current evidence on how iron regulates energy metabolism considering the TCA cycle, oxidative phosphorylation, and thermogenesis. Additionally, we relate iron-mediated metabolic regulation to obesity and obesity-related complications.

• 한국환경과학회지
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• 제26권2호
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• pp.239-248
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• 2017

Green synthesis of gold nanoparticles(GNPs) considered more ecofriendly and cost effective than other chemical methods use of dangerous reagents and solvents, improved material and energy efficiency and enhanced design of non-toxic products. In this study, we developed a green synthesis method for using Caulis in Taeniam (BCT). BCT were characterized by UV-vis, Zetasizer, TEM, XRD, and FTIR. The antioxidant activity of BCT was determined by DPPH and ABTS radical-scavenging assays, and heme oxygenase-1 induction in RAW 264.7 macrophages. The resulting BCT appeared spherical with an average diameter of 67.171.39 nm The aAntioxidant activity was increased in a dependent manner. To conclude, the green synthesis of BCT-GNPs was successful, and it appers to be useful in the for future applications.

• 한국식품영양과학회지
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• 제32권2호
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• pp.191-196
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• 2003

한국전통차로 알려진 녹차, 감잎 및 홍화의 열수추출물이 납투여된 흰쥐의 헴합성과 적혈구 중의 항산화효소 활성도 변화에 미치는 영향을 구명하기 위하여 체중 kg당 25 mg의 납을 매주 1회 경구투여 하였다. 녹차잎, 감잎 및 홍화 열수추출물은 매일 일정시간에 체중 kg당 1.26 g 수준이 되도록 4주간 경구투여하여 사육한 결과 헤마토크릿치, 헤모글로빈 함량 및 적혈구 수는 납 단독투여군이 정상군에 비하여 유의적인 감소를 보였으나 녹차, 감잎 및 홍화 열수추출물 급여로 감소 정도가 완화되었다. 혈액과 간조직 ALAD 중의 활성은 정상군에 비하여 납 단톡투여 군이 유의 적으로 감소되었으며, 한국전통차 열수 추출물 급여시 활성이 정상 수준 가까이 회복되었는데 그 효능은 혈액학적 성상 변화와 유사한 경향을 나타내었다 혈장 중 AST, ALT활성은 정상군에 비하여 납 단독투여군에서 유의적으로 증가되었으며 각각의 열수추출물 급여시 납에 의한 활성 증가가 현저하게 억제되어 정상수준으로 회복되었으며 한국전통차 종류에 따른 차이는 유의적이지는 않으나 감잎과 홍화가 효과적인 것으로 관찰되었다. 적혈구 중의 SOD와 CAT활성 및 GSH 함량은 납 단독투여시 유의적으로 증가되고 GSH-Px 활성은 감소된 반면, 녹차, 감잎 및 홍화 열수추출물 급여시 납으로 인한 적혈구의 항산화효소 활성변화가 완화되었다

• 생명과학회지
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• 제13권6호
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• pp.814-821
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• 2003

Heme 합성의 중간체이며 또한 광수용체로도 작용하는 protoporphyrin IX의 세포 내 농도 및 성장 배지에 존재하는 농도가 야생형 M. xanthus DK1622 균주로부터 측정되었다. Protoporphyrin IX의 세포 내 농도는 배양 시간이 경과함에 따라 계속 증가하여, 안정기에 최고치에 이르는 것으로 나타났다 안정기에 도달한 세포 내에는 6.4 picomoles/mg of protein의 protoporphrin IX이 존재하는 것으로 밝혀졌다. Protoporphyrin IX은 대수기 중간 시기부터 세포외로 분비가 시작되어, 안정기에 도달한 세포의 배양액에서는 세포의 단백질 대비하여 3.0 picomoles/mg of protein이 존재하는 것으로 측정되었다. 영양분의 고갈에 기인하여 형성된 포자에서도 protoporphyrin IX의 농도는 6.5 picomoles/mg of protein이 존재하는 것으로 관찰되었다. Succinylacetone을 $500\muM$ 농도로 성장 배지에 첨가하였을 경우에 protoporphyrin IX의 생산은 검출이 불가능할 정도로 방해를 받았으며, 세포성장이 저해되고 세포 성장은 정상의 절반 수준인 약 100 Klett unit에서 정지하는 것으로 나타났다. 하지만 포자의 형성은 succinylacetone의 첨가에 관계없이 89-100%의 생성율을 보였음으로 정상 농도의 protoporphyrin IX가 M. xanthus의 성장을 위해서는 중요하지만, 포자 형성 과정에 필수적인 것으로 보이지는 않는다. 안정기 세포에서 나타나는 photolysis 현상도 succinylacetone의 첨가 여부에 관계없이 유사한 수준으로 관찰되었다.