• BMB Reports
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• v.31 no.4
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• pp.307-327
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• 1998

Cytochrome c peroxidase (CcP) is a yeast mitochondrial enzyme which catalyzes the reduction of hydrogen peroxide to water using two equivalents of ferrocytochrome c. The CcP/cytochrome c system has many features which make it a very useful model for detailed investigation of heme protein structure/function relationships including activation of hydrogen peroxide, protein-protein interactions, and long-range electron transfer. Both CcP and cytochrome c are single heme, single subunit proteins of modest size. High-resolution crystallographic structures of both proteins, of one-to-one complexes of the two proteins, and a number of active-site mutants are available. Site-directed mutagenesis studies indicate that the distal histidine in CcP is primarily responsible for rapid utilization of hydrogen peroxide implying significantly different properties of the distal histidine in the peroxidases compared to the globins. CcP and cytochrome c bind to form a dynamic one-to-one complex. The binding is largely electrostatic in nature with a small, unfavorable enthalpy of binding and a large positive entropy change upon complex formation. The cytochrome c-binding site on CcP has been mapped in solution by measuring the binding affinities between cytochrome c and a number of CcP surface mutations. The binding site for cytochrome c in solution is consistent with the crystallographic structure of the one-to-one complex. Evidence for the involvement of a second, low-affinity cytochrome c-binding site on CcP in long-range electron transfer between the two proteins is reviewed.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.712-717
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• 1998

The complete nucleotide sequence of the cDNA clone encoding rat skeletal muscle myosin- binding protein H (MyBP-H) was determined and amino acid sequence was deduced from the nucleotide sequence (GenBank accession number AF077338). The full-length cDNA of 1782 base pairs(bp) contains a single open reading frame of 1454 bp encoding a rat MyBP-H protein of the predicted molecular mass 52.7kDa and includes the common consensus 1CA__TG' protein binding motif. The cDNA sequence of rat MyBP-H show 92%, 84% and 41% homology with those of mouse, human and chicken, respectively. The protein contains tandem internal motifs array (-FN III-Ig C2-FN III- Ig C2-) in the C-terminal region which resembles to the immunoglobulin superfamily C2 and fibronectin type III motifs. The amino acid sequence of the C-terminal Ig C2 was highly conserved among MyBPs family and other thick filament binding proteins, suggesting that the C-terminal Ig C2 might play an important role in its function. All proteins belonging to MyBP-H member contains `RKPS` sequence which is assumed to be cAMP- and cGMP-dependent protein kinase A phosphorylation site. Computer analysis of the primary sequence of rat MyBP-H predicted 11 protein kinase C (PKC)phosphorylation site, 7 casein kinase II (CK2) phosphorylation site and 4N-myristoylation site.

• Korean Journal of Food Science and Technology
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• v.3 no.2
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• pp.101-104
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• 1971

The dye-binding method based on the reaction of acidic orange-G dye with basic groups of protein molecule was investigated to observe its applicability to the determination of protein, basic amino acid and lysine contents in brown rice of several high-protein rice lines. The protein content of rice samples ranged from 7.91 to 10.53% and from 8.93 to 11.96% in terms of wet and dry bases, respectively. The correlation between dye-binding absorbance and protein content in terms of both dry and wet bases was highly significant; their correlation coefficients being $-0.955^{**}\;and\;-0.975^{**}$, respectively. The correlation of dye-binding absorbance lysine and basic amino acids were highly significant and their correlation coefficients were similar. Dye-binding absorbance-lysine showed a lower correlation than dye-binding absorbance-protein but a higher correlation than protein-lysine.

• Food Science of Animal Resources
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• v.39 no.4
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• pp.601-609
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• 2019

Bifidobacterium longum KACC 91563 secretes family 5 extracellular solute-binding protein via extracellular vesicle. In our previous work, it was demonstrated that the protein effectively alleviated food allergy symptoms via mast cell specific apoptosis, and it has revealed a therapeutic potential of this protein in allergy treatment. In the present study, we cloned the gene encoding extracellular solute-binding protein of the strain into the histidine-tagged pET-28a(+) vector and transformed the resulting plasmid into the Escherichia coli strain BL21 (DE3). The histidine-tagged extracellular solute-binding protein expressed in the transformed cells was purified using Ni-NTA affinity column. To enhance the efficiency of the protein purification, three parameters were optimized; the host bacterial strain, the culturing and induction temperature, and the purification protocol. After the process, two liters of transformed culture produced 7.15 mg of the recombinant proteins. This is the first study describing the production of extracellular solute-binding protein of probiotic bacteria. Establishment of large-scale production strategy for the protein will further contribute to the development of functional foods and potential alternative treatments for allergies.

• Journal of the Korean Magnetic Resonance Society
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• v.22 no.4
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• pp.125-131
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• 2018

Chemical shift perturbation (CSP) is a simple NMR technique for studying binding of a protein to various ligands. CSP is the only technique that can directly provide both a value for the dissociation constant and a binding site from the same set of measurements. To accurately analyze the CSP data, the exact binding mode such as multiple binding, should be carefully considered. In this review, we analyzed systematically the CSP data with multiple modes. This analysis might provide insight into the mechanism on how proteins selectively recognize their target ligands to achieve the biological function.

• Biomolecules & Therapeutics
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• v.4 no.1
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• pp.97-102
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• 1996

To investigate whether human $\beta$$_2$-adrenergic receptor devoid of the C-terminal two transmembrane helices retain its ligand binding activity and specificity, 5'780-bp DNA fragment of the receptor gene which encodes amino acid 1-260 of human $\beta$$_2$-adrenergic receptor was subcloned into the bacterial fusion protein expression vector and expressed as a form of glutathione-S-transferase (GST) fusion protein in E. coli DH5$\alpha$. The receptor fusion protein was expressed as a membrane bound form which was verified by SDS-PAGE and Western blot. The fusion protein expressed in this study specifically bound $\beta$-adrenergic receptor ligand [$^3$H] Dihydroalprenolol. In saturation ligand binding assay, the $K_{d}$ value was 7.6 nM which was similar to that of intact $\beta$$_2$-adrenergic receptor in normal animal tissue ( $K_{d}$=1~2 nM) and the $B_{max}$ value was 266 fmol/mg membrane protein. In competition binding assay, the order of binding affinity of various adrenergic receptor agonists to the fusion protein was isoproterenol》epinephrine norepinephrine, which was similar to that of intact receptor in normal animal tissue. These results suggest that N-terminal five transmembrane helices of the $\beta$$_2$-adrenergic receptor be sufficient to determine the ligand binding activity and specificity, irrespective of the presence or absence of the C-terminal two transmembrane helices.s.s.s.

• Journal of the Korean Magnetic Resonance Society
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• v.20 no.1
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• pp.22-26
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• 2016

FANCJ is a DNA helicase which contributes genome stability by resolving G-quadruplex DNA from 5' to 3' direction. In addition to main ATPase helicase core, FANCJ has the protein binding region at its C-terminal part. BRCA1 and BLM are the binding partner of FANCJ and these protein-protein interactions contribute genomic stability and the proper response to replication stress. As the first attempt for studying FANCJ-BLM interaction, we prepared BLM binding region of FANCJ and characterized with CD and NMR spectroscopy. FANCJ (881-941) with N-ter 6xHis was purified as the oligomer. Secondary structure prediction based on CD data revealed that FANCJ (881-941) composed with ${\beta}$ sheet, turn and coils.$^1H-^{15}N$ HSQC spectra showed nonhomogeneous peak intensities with less number of peaks comparing than the number of amino acids in the construct. It indicated that optimization should be necessary for detailed further structural studies.

• Ocean and Polar Research
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• v.23 no.4
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• pp.337-345
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• 2001

A Cd-binding protein was identified in the renal cytosol of the Antarctic clam Laternula elliptica which naturally contains high concentrations of Cd. The Cd-binding protein showed similar characteristics of metallothionein (MT) in molecular weight (about 10-12 kDa) and low spectral absorbance at 280 nm with relatively high absorbance at 254nm. Results of immuno-histochemical staining suggested that the MT-like Cd-binding protein was mainly located in the epithelial cells of the kidney. The MT-like protein was a major ligand of cytosolic Cd as shown in the elution profiles of chromatography and may play an important role in Cd sequestration and accumulation in L. elliptica kidney. A considerable amount of Cd was also found to be associated with particulate fraction, indicating the sequestration to particulate fraction is as important as binding to the cytosolic MT-like protein in Cd accumulation in the kidney.

• Food Science of Animal Resources
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• v.32 no.3
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• pp.301-307
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• 2012

We investigated the effects of non-meat protein binders combined with glucono-${\delta}$-lactone (GdL) on the binding properties regarding restructured pork prepared by high-pressure treatment. Soy protein isolate (SPI), casein (CS), whey protein concentrate (WPC), and egg white (EW) were used as non-meat protein binders and compared with the control (no binder) and with the ${\kappa}$-carrageenan (KC) treatment. The compression and depression rates were 2.3 and 37 MPa/s, respectively, and pressurization was conducted at 200 MPa for 30 min at $4^{\circ}C$. After pressurization, the physical properties (pH, water-holding capacity, color, tensile strength, and microscopic structure) of the sample were evaluated. The combination of pressurization with acidification enabled cold-set meat binding, and the binding strength of restructured pork was enhanced by the addition of non-meat proteins. Among binders, SPI demonstrated the best efficiency in binding meat pieces. Therefore, the present study demonstrated that the combination of acidification and pressurization processes with the utilization of non-meat protein binders has a potential benefit in meat restructuring.

• Journal of Life Science
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• v.8 no.2
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• pp.119-125
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• 1998

Column-purified double-stranded RNA binding factor (RBF) protein was tested for its binding affinity for the different forms of nucleic acids structure such as single-stranded(ss) and double-stranded(ds)RNA and ss- and dsDNA. The RBF protein was incubated with each of these nucleic acid structures in separate reactions and its comparative binding affnity was visualized by SDS-polyacrylamide gel electrophoresis. The RBF protein bound to the dsRNA molecule to form a tight RNA:protein complex in agreement with previous studies, but not to the other nucleic acid molecules confirming its distinctive affinity for the dsRNA structure. In phosphorylation assay in vito, the purified RBF protein significantly inhibited the autophosphorylation of the PKR derived from not only human but mouse source in the presence of poly(I):poly(C). It is suggesting that PKR vs. RBF is similarly under a competitive interaction among different eukaryotic organisms during protein synthesis.