• Applied Biological Chemistry
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• v.44 no.4
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• pp.219-223
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• 2001

Effects of hemoglobin (Hgb) concentration and degree of hydrolysis (DH) of Hgb on the separation of heme-iron were examined to produce highly enriched heme-iron from Hgb hydrolysate. Separation efficiency of Hgb hydrolysate with different DH was studied at wide pH range (pH $1.0{\sim}11.0$). Separation efficiency expressed as heme-iron/peptide ratio increased with decreasing Hgb concentration. When 5% Hgb (pH 10.0) was hydrolyzed using commercially available Esperase for 5 h at $50^{\circ}C$, DH was 25%. The precipitation of heme-iron-enriched peptides were remarkably high at pH range $3{\sim}6$. Optimal pH range for heme-iron with high heme-iron/peptide ratio shifted to acidic pH with increasing DHs of Hgb. The enriched heme-iron fraction in the precipitates showed a single band through urea-SDS-PAGE, with a molecular mass of 1 kDa. In the dry heme-iron product produced in a pilot bioreactor, content of heme-iron and heme-iron/peptide ratio were 27.1 and 38.7%, respectively, and production yield was 9.3%.

• Applied Biological Chemistry
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• v.46 no.2
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• pp.130-133
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• 2003

A method for separating heme-iron from hemoglobin (Hgb) hydrolysate by dialysis was developed. Recovery of heme-iron increased with increasing Hgb concentration, whereas rejection of peptide and separation effciency expressed by HP ratio (heme-iron/peptide) did not show significant differences. HP ratio increased with increases in the degree of hydrolysis of Hgb and $KH_2PO_4$ concentrations of dialysis solution. Recovery of heme-iron decreased with increase in the pH of dialysis solution due to wash-out of heme-iron across the dialysis membrane caused by increase in solubility of heme-iron. Rejections of peptide were 74.5 and 87.5% (2 and 5 kDa of cut off size, respectively), whereas recovery of heme-iron decreased from 86.5 (2 kDa) to 63.1% (25 kDa). Amounts of heme-iron and peptide of dried heme-iron product were 21.7 and 77.0%, and HP ratio and production yield were 28.2 and 6.5%, respectively.

• YAKHAK HOEJI
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• v.45 no.1
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• pp.78-84
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• 2001

Heme oxygenase is a rate-limiting enzyme in heme catabolism that cleaves heme to form biliverdin, iron, and carbon monoxide. Heme oxygenase-1 is expressed in many types of cells and tissues and is highly induced in response to oxidative stress. Carbon monoxide, one of the products of heme oxygenase, can stimulate soluble guanylate cyclase and dilate the vascular smooth muscle. So, the induction of heme oxygenase by lipopolysaccharide (LPS)-induced oxydative stress and the effect of the resultant carbon monoxide on aortic contractility were examined in this study. Zinc protoporphyrine IX (ZnPP), a inhibitor of heme oxygenase, elicited weak contraction of thoracic aortic ring, and this effect was more potent in aorta of LPS-treated rats than control and was blocked by methylene blue. The hyperreactivity to ZnPP in LPS-treated group was blocked by co-treatment with aminoguanidine. In the aortic ring of LPS-treated rats, ZnPP didn't change the vasoreactivity to phenylephrine or acetylcholine. ZnPP elicited hyper-tensive effect in concious rats, and pretreatment with LPS did not affect this effect. Prazosin significantly diminished the hypertensive effect of ZnPP. These results indicate that LPS induced heme oxygenase in aotra, and the resultant carbon monoxide diminished the aortic reactivity to vasoconstrictor.

• Environmental Engineering Research
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• v.19 no.2
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• pp.139-143
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• 2014

Catalytic degradation of pentachlorophenol in soil by heme and hydrogen peroxide has been hypothesized to occur through nonspecific catalytic reactions similar to those involving ligninase. The present study examines the evidence for a heme catalytic mechanism for the oxidation of organic compounds. In the presence of hydrogen peroxide, heme is converted to the ferryl heme radical (Hm-$Fe^{+4{\cdot}}$), which can oxidize organic compounds, such as 5-aminosalicylic acid (5-ASA). A second 5-ASA may later be oxidized by ferryl heme (Hm-$Fe^{+4}$), which reverts to the ferric heme state (Hm-$Fe^{+3}$) to complete the cycle. We believe that this catalytic cycle is involved in the degradation of hazardous pollutants, such as polycyclic aromatic hydrocarbons (PAHs). Remediation via heme catalytic reactions of PAHs in soil from a pole yard was evaluated, and about 96% of PAHs was found to disappear within 42 days after treatment with heme and hydrogen peroxide. In addition, benzo[a]pyrene and six other PAHs were undetectable among a total of 16 PAH compounds examined. Therefore, we propose heme catalysis as a novel technology for the remediation of hazardous compounds in contaminated soil.

• Journal of Nutrition and Health
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• v.25 no.7
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• pp.608-616
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• 1992

Using the hematofluiorometer normal values of the erythrocyte zinc protoporphyrin(ZPP) and ZPP/Heme ratio were measured in 312 males and 163 females aged from 6 month to 73 years old and compared with those of anemic persons. The mean$\pm$SD values of ZPP of normal Koreans were 28.5$\pm$6.4($\mu\textrm{g}$/dl) in males and 3.18$\pm$7.7 in females. the mean$\pm$SD of ZPP/Heme ratio were 49.5$\pm$12.3($\mu$mol/mol heme) in males and 62.0$\pm$15.8 in females. The difference in the mean ZPP and ZPP/Heme ratio values between male and female subjects were statistically signficant(p<0.0001) In male subjects the mean ZPP and ZPP/Heme ratio of the age groups less than 15 years old were higher than adult groups and the difference between age groups was significant(p<0.005 and p<0.0001 respecti-vely) The normal upper limit of the mean$\pm$2SD in normal male and female subjects were 41.3 and 47.2 for ZPP and 74.1 and 93.6 for ZPP/Heme ratio respectively. The mean values of ZPP and ZPP/Heme ratio measured in the anemic persons were higher than those of normal subjects and did not show any significant difference by the sex and age groups except in 6-14 years male groups. The test specificity(positivity) analyzed in the anemic persons by the cut-off values calculated from the normal data were 50.6% for ZPP and 73.0% for ZPP/Heme ratio. The correlation analysis between blood hemoglobin and erythrocyte ZPP or ZPP/Heme ratio in the total 801 normal and anemic subjects showed that there are very high logarithmic correlation between the hemoglobin levels and ZPP/Heme ratio (r=-0.8339) and high correla-tion between the hemoglobin levels and ZPP concentrations(r=-0.6372) These results suggested that the measurement of the erythrocyte ZPP and ZPP/Heme ratio with the hematofluorometer can be a usuful screening method for iron deficiency anermin because they provide a reliable immediate results with a small amount of sample and are relatively simple and inexpensive.

• Analytical Science and Technology
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• v.11 no.1
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• pp.73-78
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• 1998

The reverse detection heteronuclear multiple quantum coherence, HMQC study of metcyano complex of horse myoglobin(MbCN) has provided the complete assignment of hyperfine shifted resonances of heme carbons attached with proton(s). The application of HMQC experiment to the paramagnetic low-spin MbCN gives clear $^1H$ and $^{13}C$ coherences for the paramagnetic amino acid residues as well as heme side chains, and can be extended to the low-spin paramagnetic hemoprotein derivative for the assignment of natural abundance $^{13}C$ resonances. This assignment strategy can avoid possible ambiguities that may result from the sole utilization of $^1H$ nuclear Overhauser effect for the assignment of heme $^1H$ signals resonating in the diamagnetic region. The resulting 2,4-vinyl ${\alpha}$-carbons and 7-propionate ${\beta}$-carbon follow anomalous anti-Curie behavior, and are indicative of incoplanarity with heme plane. Magnetic/electronic asymmetry of heme induced by proximal histidine(His) makes spread that the hyperfine shifted heme carbon resonances over the range of 250 ppm at $25^{\circ}C$. These heme carbon resonances would be the much more sensitive probe than those of proton resonances in analyzing the nature of heme electronic structure of myoglobin.

• Journal of Microbiology and Biotechnology
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• v.19 no.6
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• pp.604-609
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• 2009

To investigate the potential use of microbial heme as an iron source, recombinant Escherichia coli coexpressing ALA synthase (HemA) as well as the NADP-dependent malic enzyme (MaeB) and dicarboxylic acid transporter (DctA) were cultured. The typical red pigment extracted from the recombinant E. coli after 38 h showed highest absorbance at 407 nm, and the amount of iron in 38.4 mg of microbial heme extract derived from 6-1 fermentation broth was 4.1 mg. To determine the commercial potential of the recombinant E.coli-synthesized iron-associated heme as an iron source, mice were fed the iron-free provender with the microbial heme extract. The average body weight reduction of mice fed non-iron provender was 2.3%, whereas no detectable weight loss was evident in mice fed microbial heme addition after 15 days. The heme content of the blood from microbial heme fed mice was 4.2 mg/ml whereas that of controls was 2.4 mg/ml, which implies that the microbial heme could be available for use as an animal iron source.

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

• Bulletin of the Korean Chemical Society
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• v.17 no.9
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• pp.820-826
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• 1996

The p2H dependence of the NMR chemical shifts of the proton signals of heme methyl groups and ionizable groups in the vicinity of the heme were investigated. The p2H titration of heme methyl signals in four macroscopic oxidation states by saturation tranfer method was performed in the range between p2H 5.2 and 9.0. While the p2H dependence of the heme methyl resonance in fully oxidized state was small, most resonances in the intermediate oxidation states showed certain shifts. Particularly, methyl resonances of heme 1 (sequential heme numbering) exhibited sharp p2H dependence in acidic range. β-CH2 of the propionate of hemes 1 and 4 were titrated in the range of p2H 4.5-9.0. Only the 6-propionate group of heme 1 was protonated in this p2H range and its titration curve was similar to those of methyl resonances of heme 1 in intermediate oxidation states. Analysis of the microscopic redox potentials showed that they change depending on p2H. The ionizable groups responsible for the p2H dependence of these potentials are 6-propionate of heme 1 in acidic range and His 67 in basic range.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.2
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• pp.162-165
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• 2002

To determine changes of heme compounds on lipid oxidation during repeat heating in white muscled fish (yellowfin sole and yellow croaker), myoglobin, metmyoglobin, total iron, nonheme iron and heme iron contents were analysed. Myoglobin content was decreased in the step of repeat heating. Especially, it was decreased the most rapidly roasted at 180$^{\circ}C$ for 20 min in fillet samples. The skinless fillet roasted at the lower temperature resulted in the higher level of metmyoglobin associated with the reduced myoglobin. Regardless of roasted temperature and time, total iron content was not change in contrast of raw meat throughout processing. Nonheme iron content was increased, but heme iron content was decreased during roasted, heated and reheated.