• Journal of Microbiology and Biotechnology
• /
• v.27 no.3
• /
• pp.500-506
• /
• 2017

To investigate the potential applications of bacterial heme, aminolevulinic acid synthase (HemA) was expressed in a Corynebacterium glutamicum HA strain that had been adaptively evolved against oxidative stress. The red pigment from the constructed strain was extracted and it exhibited the typical heme absorbance at 408 nm from the spectrum. To investigate the potential of this strain as an iron additive for swine, a prototype feed additive was manufactured in pilot scale by culturing the strain in a 5 ton fermenter followed by spray-drying the biomass with flour as an excipient (biomass: flour = 1:10 (w/w)). The 10% prototype additive along with regular feed was supplied to a pig, resulting in a 1.1 kg greater increase in weight gain with no diarrhea in 3 weeks as compared with that in a control pig that was fed an additive containing only flour. To verify if C. glutamicum-synthesized heme is a potential electron carrier, lactic acid bacteria were cultured under aerobic conditions with the extracted heme. The biomasses of the aerobically grown Lactococcus lactis, Lactobacillus rhamosus, and Lactobacillus casei were 97%, 15%, and 4% greater, respectively, than those under fermentative growth conditions. As a potential preservative, cultures of the four strains of lactic acid bacteria were stored at $4^{\circ}C$ with the extracted heme and living lactic acid bacterial cells were counted. There were more L. lactis and L. plantarum live cells when stored with heme, whereas L. rhamosus and L. casei showed no significant differences in live-cell numbers. The potential uses of the heme from C. glutamicum are further discussed.

• BMB Reports
• /
• v.43 no.5
• /
• pp.330-336
• /
• 2010

5-Aminolevulinate (ALA) is well-known as an essential biosynthetic precursor of all tetrapyrrole compounds, which has been suggested to improve plant salt tolerance by exogenous application. In this work, the gene encoding aminolevulinate synthase (ALA-S) in yeast (Saccharomyces cerevisiae Hem1) was introduced into the genome of Arabidopsis controlled by the Arabidopsis thaliana HemA1 gene promoter. All transgenic lines were able to transcribe the YHem1 gene, especially under light condition. The chimeric protein (YHem1-EGFP) was found co-localizing with the mitochondria in onion epidermal cells. The transgenic Arabidopsis plants could synthesize more endogenous ALA with higher levels of metabolites including chlorophyll and heme. When the $T_2$ homozygous seeds were cultured under NaCl stress, their germination and seedling growth were much better than the wild type. Therefore, introduction of ALA-S gene led to higher level of ALA metabolism with more salt tolerance in higher plants.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.6
• /
• pp.880-886
• /
• 2015

Bacterial heme was produced from a genetic-engineered Escherichia coli via the porphyrin pathway and it was useful as an iron resource for animal feed. The amount of the E. coli-synthesized heme, however, was only few milligrams in a culture broth and it was not enough for industrial applications. To analyze heme biosynthetic pathways, an engineered E. coli artificially overexpressing ALA synthase (hemA from Rhodobacter sphaeroides) and pantothenate kinase (coaA gene from self geneome) was constructed as a bacterial heme-producing strain, and both the transcription levels of pathway genes and the intermediates concentrations were determined from batch and continuous cultures. Transcription levels of the pathway genes were not significantly changed among the tested conditions. Intracellular intermediate concentrations indicated that aminolevulinic acid (ALA) and coenzyme A (CoA) were enhanced by the hemA-coaA co-expression. Intracellular coproporphyrinogen I and protoporphyrin IX accumulation suggested that the bottleneck steps in the heme biosynthetic pathway could be the spontaneous conversion of HMB to coproporphyrinogen I and the limited conversion of protoporphyrin IX to heme, respectively. A strategy to increase the conversion of ALA to heme is discussed based on the results.

• 대한생식의학회:학술대회논문집
• /
• 2006.06a
• /
• pp.6-11
• /
• 2006

Our previous study demonstrates a rapid activation of atypical PKC${\zeta}$ by the ovulatory dose of LH/hCG. The present study was therefore designed to identify PKC${\zeta}$ regulated-genes in rat ovarian preovulatory granulosa cells. Preovulatory granulosa cells cultured in the presence of myristoylated PKC${\zeta}$ pseudosubstrate peptide were subjected to identify differentially expressed genes by using anneling control primer RT-PCR. As a result, among sixteen genes identified, six genes (testin, glypican-4, retrovirus SC1, connective growth factor, aminolevulinic acid synthase1 and serum- inducible kinase) were rapidly stimulated by hCG. Northern blot analysis demonstrated that all these genes were rapidly stimulated by hCG and declined thereafter. In situ hybridization analysis revealed the expression of these genes in granulosa cells of preovulatory follicles. The present study demonstrates time- and cell-specific expression of PKC${\zeta}$-regulated genes, and may imply that these genes play a specific role(s) during LH-induced ovulation.

• Biomolecules & Therapeutics
• /
• v.31 no.5
• /
• pp.526-535
• /
• 2023

Breast cancer is the most common cancer and a frequent cause of cancer-related deaths among women wordlwide. As therapeutic strategies for breast cancer have limitations, novel chemotherapeutic reagents and treatment strategies are needed. In this study, we investigated the anti-cancer effect of synthetic homoisoflavane derivatives of cremastranone on breast cancer cells. Homoisoflavane derivatives, SH-17059 and SH-19021, reduced cell proliferation through G2/M cell cycle arrest and induced caspase-independent cell death. These compounds increased heme oxygenase-1 (HO-1) and 5-aminolevulinic acid synthase 1 (ALAS1), suggesting downregulation of heme. They also induced reactive oxygen species (ROS) generation and lipid peroxidation. Furthermore, they reduced expression of glutathione peroxidase 4 (GPX4). Therefore, we suggest that the SH-17059 and SH-19021 induced the caspase-independent cell death through the accumulation of iron from heme degradation, and the ferroptosis might be one of the potential candidates for caspase-independent cell death.

• Journal of Microbiology and Biotechnology
• /
• v.22 no.12
• /
• pp.1653-1658
• /
• 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.

• Microbiology and Biotechnology Letters
• /
• v.47 no.3
• /
• pp.337-342
• /
• 2019

We published that bacterial heme was over-produced in a recombinant Corynebacterium glutamicum expressing 5-aminolevulinic acid synthase ($hemA^+$) under control of a constitutive promoter ($P_{180}$) and the heme-producing C. glutamicum had commercial potentials; as an iron feed additive for swine and as a preservative for lactic acid bacteria. To enhance the heme production, the $hemA^+$ gene was expressed under controls of various promoters in the recombinant C. glutamicum. The $hemA^+$ expression by $P_{gapA}$ (a constitutive glycolytic promoter of glyceraldehyde-3-phosphate dehydrogenase) led 75% increase of heme production while the expression by $P_{H36}$ (a constitutive, very strong synthetic promoter) resulted in 50% decrease compared with the control ($hemA^+$ expression by $P_{180}$ constitutive promoter). The $hemA^+$ expression by a late log-phase activating $P_{sod}$ (an oxidative-stress responding promoter of superoxide dismutase) led 50% greater heme production than the control. The $hemA^+$ expression led by a heat-shock responding chaperone promoter ($P_{dnaK}$) resulted in 121% increase of heme production at the optimized heat-shock conditions. The promoter strength and induction phase are discussed based on the results for the heme production at an industrial scale.