• BMB Reports
• /
• v.34 no.4
• /
• pp.365-370
• /
• 2001

We constructed a comparative expression system in order to produce recombinant human ferritin homo- and heteropolymers in Escherichia coli. Human ferritin H-(hfH) and L-chain (hfL) genes were expressed without amino acid changes under the control of a tac promoter. Ferritin heteropolymers of varying subunit composition were also produced by combining two different expression systems, a bicistronic expression system and a coplasmid expression system. As a result, recombinant H-chain ferritin and ferritin heteropolymers were catalytically active in forming iron core in vivo. In particular, the ferritin heteropolymer that is composed of 7% H-subunit and 93% L-subunit was capable of forming an iron core of the protein, while the L-chain ferritin homopolymer was inactive in vivo. This result indicates that the two H-subunits (i.e., 7% H-subunit content) are important to keep ferritin active in the cells. In addition, human ferritins were identified as the major iron binding proteins in the transformed cells. Also, the amount of iron bound to the recombinant ferritins was proportional to the H-subunit content in ferritin heteropolymers in vivo.

• 한국생물공학회:학술대회논문집
• /
• 2001.11a
• /
• pp.697-700
• /
• 2001

Iron is an essential nutrient for most organisms, which supplied to them in a protein-iron complex known as ferritin. Ferritins are multimeric proteins found in prokaryotes, plants and animals. They are consisted of spherical shell of 24 subunits defining a cavity of about 8nm in diameter, where an iron core is laid down. Expression of ferritin in recombinant E. coli at $37^{\circ}C$ led to the accumulation of recombinant ferritin. Insoluble form of ferritin was separated from disrupted cells, followed by various primary separation steps with two kinds of buffers. Collected samples from the primary steps were purified by DEAE-cellulose gels packed in a column. The fractions from the DEAE column were assayed to gain the amount and the purity of ferritin by using HPLC and SDS-PAGE.

• 한국생물공학회:학술대회논문집
• /
• 2002.04a
• /
• pp.510-513
• /
• 2002

Iron is an essential nutrient for most organisms, which supplied to them in a protein-iron complex known as ferritin. Ferritins are multimeric proteins those are consisted of spherical shell of 24 subunits defining a cavity of about 8nm in diameter. Soluble form of ferritin was separated from disrupted cells, followed by silica powder adsorption. Ferritin was recovered from silica-poweder by distiiled water, which was applied to DEAE anion exchage chromatography. Collected fractions from the DEAE column were assayed to gain the amount and the purity of ferritin by using GF-HPLC.

• Journal of Life Science
• /
• v.15 no.3 s.70
• /
• pp.439-446
• /
• 2005

Ferritin is known to be the principle iron-storage protein in a wide variety of rganisms. The electro­phoretic mobility and immunological cross-reactivity of dog splenic ferritin were compared with those of horse, bovine, and pig splenic ferritin after isolation using heat treatment, salting out, column chromatography, and ultrafiltration. These isolation methods allowed the recovery of $\~84{\mu}g$ of the ferritin per g of spleen. The iron content in the dog ferritin was $22.7\%$, which appeared to be higher than those in the other mammalian ferritins tested. The electrophoretic mobility of the dog ferritin under nondenaturing conditions was similar to its bovine counterpart, whereas it was more identical to pig and horse ferritins on an SDS-polyacrylamide gel. The molecular weight of the dog ferritin subunit was 19.5 kDa on an SDS-polyacrylarnide gel, and the subunit was unable to bind with iron. The polyclonal anti-dog ferritin raised in rats was able to cross-react with the pig, bovine, and horse ferritins, upon Ouchterlony double immunodiffusiion. A Western blot analysis also revealed that the anti-dog ferritin, which specifically bound with the dog ferritin subunit, could also recognize the horse, bovine, and pig ferritin subunits and the maximum cross-reactivity was exhibited with the pig ferritin subunit, indicating that the dog ferritin is immunochemically more similar to the pig ferritin than its other mammalian counterparts. Accordingly, these results elucidate the biochemical and immunochemical characteristics of dog ferritin that might have a potential to be applied as an oral iron supplement to treat iron deficiency anemia.

• Proceedings of the Korean Aquaculture Society Conference
• /
• 2003.10a
• /
• pp.43-43
• /
• 2003

EST analysis was performed to identify stress-responsive and immune-related genes from rock bream (Oplegnathus fasciatus). cDNA libraries were constructed with liver and randomly chosen 624 clones were subjected to automated sequence analysis. Of 624 clones sequenced in total, approximately 15% of ESTs was novel sequences (no match to GenBank) or sequences with high homology to hypothetical/unknown genes. The bioinforamtic sequence analysis including functional clustering, homology grouping, contig assembly with electronic northern and organism matches were carried out. Several potential stress-responsive biomarker and/or immune-related genes were identified in all the tissues examined. It included lectins, ferritins, CP450, proteinase, proteinase inhibitors, anti-oxidant enzymes, various heat-shock proteins, warm temperature acclimation protein, complements, methyltransferase, zinc finger proteins, lysozymes, macrophage maturation associated protein, and others. This information will offer new possibilities as fundamental baseline data for understanding and addressing their molecular mechanism involved in host defense and immune systems of this species.

• Journal of Magnetics
• /
• v.21 no.1
• /
• pp.20-24
• /
• 2016

Magnetic properties of bio-magnetic molecule ferritin have been investigated. Two ferritin samples were synthesized under different magnetic fields, 0 and 9.4 T, respectively. This work is focused on the influence of magnetic field on biomineralization process. While magnetization vs. temperature (M-T) data of both samples measured at 1000 Oe are almost identical except for low temperature region (T < 6 K), magnetization vs. field (M-H) data show noticeable difference. From an analysis of M-H data by using a modified Langevin function, we could extract the saturation magnetization $m_0$(T), the effective magnetic moment ${\mu}_{eff}$(T) and the linear susceptibility x(T). The difference between the samples is most prominent in the x(T), whereby the x(T) of the sample prepared at 9.4 T is 1.7 times bigger than that of the other. In addition, from hysteresis and relaxation measurements, we found the sample prepared at 9.4 T showed strikingly smaller coercivity and slower relaxation.

• BMB Reports
• /
• v.40 no.1
• /
• pp.82-87
• /
• 2007

Our heterologous expression system of the human ferritin H-chain gene (hfH) allowed us to characterize the cellular effects of ferritin in yeasts. The recombinant Saccharomyces cerevisiae (YGH2) evidenced impaired growth as compared to the control, which was correlated with ferritin expression and with the formation of core minerals. Growth was recovered via the administration of iron supplements. The modification of cellular iron metabolism, which involved the increased expression of high-affinity iron transport genes (FET3 and FTR1), was detected via Northern blot analysis. The findings may provide some evidence of cytosolic iron deficiency, as the genes were expressed transcriptionally under iron-deficient conditions. According to our results examining reactive oxygen species (ROS) generation via the fluorescence method, the ROS levels in YGH2 were decreased compared to the control. It suggests that the expression of active H-ferritins reduced the content of free iron in yeast. Therefore, present results may provide new insights into the regulatory network and pathways inherent to iron depletion conditions.

• Journal of fish pathology
• /
• v.26 no.3
• /
• pp.295-301
• /
• 2013

Ferritin is an evolutionarily conserved protein that plays an important role in iron storage and detoxification. In this study, the gene encoding a ferritin H subunit homologue (RbFH) was cloned from rock bream (Oplegnathus fasciatus) and analyzed at the expression. The full-length ferritin H cDNA was 1162 bp long and contained an open reading frame (ORF) of 531 bp that encoded 177 amino acid residues with a predicted molecular mass of 20.8 kDa. The 5' UTR was 297 bp in length, and the 3' UTR 298 bp, and preceded by a 5'-untranslated region that contains a putative Iron Regulatory Element (IRE). The deduced amino acid sequence of RbFH shares extensive sequence identities with the H ferritins of a number of fish species and contains the ferroxidase center that is preserved in ferritin H subunits. Examination of tissue specific expression indicated that RbFH expression was most abundant in PBLs, RBC, liver and muscle.

• Clinical and Experimental Pediatrics
• /
• v.59 no.7
• /
• pp.308-311
• /
• 2016

We report a human parechovirus-3 (HPeV-3) infection in 2 neonates who had prolonged fever (>5 days) with palmar-plantar erythema. This distinctive rash was observed 4-5 days after fever onset, just before defervescence. Elevated aspartate aminotransferase, lactate dehydrogenase, and ferritin levels were characteristic laboratory findings in the 2 cases, suggesting tissue damage caused by hypercytokinemia. Case 1 was treated with intravenous immunoglobulin, considering the possibility of severe systemic inflammatory responses. The initial ferritin level was 385 ng/mL (range, 0-400 ng/mL); however, the level increased to 2,581 ng/dL on day 5 after fever onset. Case 2 presented with milder clinical symptoms, and the patient recovered spontaneously. HPeV-3 was detected in cerebrospinal fluid and/or blood samples, but no other causative agents were detected. The findings from our cases, in accordance with recent studies, suggest that clinical features such as palmar-plantar erythema and/or hyperferritinemia might be indicators of HPeV-3 infection in neonates with sepsis-like illness. In clinical practice, where virology testing is not easily accessible, clinical features such as palmar-plantar erythema and/or hyperferritinemia might be helpful to diagnose HPeV-3 infection.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.18 no.2
• /
• pp.100-107
• /
• 2015

Purpose: We investigated the iron status of very low birth weight infants receiving multiple erythrocyte transfusions during hospitalization in the neonatal intensive care unit (NICU). Methods: We enrolled 46 very low birth weight infants who were admitted to the Kyungpook National University Hospital between January 2012 and December 2013. Serum ferritin was measured on their first day of life and weekly thereafter. We collected individual data of the frequency and volume of erythrocyte transfusion and the amount of iron intake. Results: A total of 38 (82.6%) of very low birth weight infants received a mean volume of $99.3{\pm}93.5mL$ of erythrocyte transfusions in NICU. The minimum and maximum serum ferritin levels during hospitalization were $146.2{\pm}114.9ng/mL$ and $456.7{\pm}361.9ng/mL$, respectively. The total volume of erythrocyte transfusion was not correlated to maximum serum ferritin concentrations after controlling for the amount of iron intake (r=0.012, p=0.945). Non-transfused infants took significantly higher iron intake compared to infants receiving ${\geq}100mL/kg$ erythrocyte transfusion (p<0.001). Minimum and maximum serum ferritin levels of non-transfused infants were higher than those of infants receiving <100 mL/kg erythrocyte transfusions (p=0.026 and p=0.022, respectively). Infants with morbidity including bronchopulmonary dysplasia or retinopathy of prematurity received a significantly higher volume of erythrocyte transfusions compared to infants without morbidity (p<0.001). Conclusion: Very low birth weight infants undergoing multiply erythrocyte transfusions had excessive iron stores and non-transfused infants also might had a risk of iron overload during hospitalization in the NICU.