• Food Science and Preservation
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• v.19 no.3
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• pp.438-442
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• 2012

To prepare calcium-binding peptides as calcium supplement, barley proteins were hydrolyzed using Flavourzyme for 18 h and the hydrolysates were ultra-filtered under 3 kDa as a molecular weight. The resultant filtered peptides were fractionated using ion exchange and normal-phase high performance liquid chromatography. Then each fraction that was obtained was determined for its calcium-binding activity to isolate the calcium-binding peptides. As a result, the highest calcium-binding peptide fraction was obtained, and the results suggest that barley protein hydrolysates can be used as a calcium supplement.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.250-250
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• 1994

진정성 cyclopeptide인 sanjoinine-A의 진정작용을 분자 수준에서 밝히고자 sanjoinine-A의 ionophore 활성과 칼슘 결합 단백질인 calmodulin과의 결합을 CD와 NMR을 이용하여 연구하였다 sanjoinine-A는 칼슘과 마그네슘에 대하여 ionophore 활성이 있었으며 calmodulin과 두 단계로 결합한다는 것을 알 수 있었다. sanjoinine-A는 칼슘의 유무에 관계없이 calmodulin과 결합하였으며 CD와 NMR 스펙트럼상에서 현저한 변화가 있었다. sanjoinine-A가 calmodulin과 결합시 생체 내에서 활성 상태인 칼슘결합 calmodulin에 비하여 a-helix 구조비율이 감소하였으며 칼슘결합 loop에서 수소결합을 하고있는 amide 수소들의 exchange rate가 현저히 빨라졌다. sanjoinine-A는 calmodulin과 결합하여 칼슘결합 loop 주위의 공간구조를 변형시켜 그 활성을 변화시키는 것으로 보인다.

• Food Science and Preservation
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• v.22 no.2
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• pp.297-302
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• 2015

Calcium is one of the essential mineral for the humans due to its crucial physiological functions in the body. Calcium deficiency results in many diseases, such as osteoporosis. Therefore, calcium supplements are available as a functional food. However, most calcium supplements in the market have a limitation due to poor absorption and low bioavailability. Thus, calcium-chelated peptides for improving the absorption rate of calcium have been isolated from foods including porcine meat and bone meal (MBM), and mussel using the enzymatic hydrolysis of their protein. The hydrolysates of food were ultra-filtered in order to obtain small peptides less than 3 kDa and the Ca-binding peptides were isolated via the anion exchange chromatography. The binding activity and concentration of Ca-binding pepetides were determined. In particular, the MBM and mussel protein hydrolysates were fractionated by mono Q and Q-Sepharose, respectively. As a result, among the fractions, the fractions of MBM F2 and mussel F3 showed the highest Ca-binding activity. These results suggest that MBM and mussel protein hydrolysates can be used as calcium supplements.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.271-277
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• 2014

Purpose: The purpose of this study was to investigate the immunoreactivity of calretinin in Brazilian opossum (Monodelphis domestica) retina. Calcium-binding protein calretinin is known to play a key role in calcium-mediated signal transduction. Methods: Experiments have been performed by standard immunocytochemical techniques on retina of the Brazilian opossum. Results: Calretinin-immunoreactivity was exhibited within the horizontal subpopulations, AII amacrine and ganglion cell subpopulations in the Brazilian opossum retina. Especially, all calretinin-immunoreactive AII amacrine cells also expressed parvalbumin. Conclusions: Similar to other mammalian retinas, calretinin-immunoreactivity was also observed within the AII amacrine cells in the Brazilian opossum retina. Thus, calretinin can be a marker of AII amacrine cells in the Brazilian opossum retina.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.343-343
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• 1994

1. 목 적 : 혈액 중에 존재하는 약물은 대부분 혈장 단백질과 결합하며, 비단백 결합성 약물만이 생체막을 통과하여 여러 조직에 분포되고, target eel1에서 약리학적 작용을 나타내며, 대사, 배설 될 수 있다. 단백결합율이 높은 약물일수록 비결합성 약물의 양은 적어지며, 따라서 비결합성 약물의 증가는 약효의 상승을 의미하게 된다. 최근 만성 질환에 한약의 병용투여가 증가하고 있다. 본 실험에서는 단백결합율이 높은 감초의 주성분인 Glycyrrhizic acid(GA)와 고혈압 치료제로 많이 사용되는 칼슘 길항제를 병용 투여할 경우, 칼슘 길항제의 혈장 단백결합에 미치는 영향을 살펴 보았다. 2. 방 법 : Diltiazem hydrochloride, Verapamil hydrochloride, Nifedipine 와 GA를 model 약물로 하여 평형 투석법과 한외 여과법을 이용하여 fatty acid free human serum albumin(HSA), Low density lipoprotein( LDL ), of-Acid glycoprotein(AAG), plasma 각각에 대한 결합율을 HPLC로 분석하였으며 또한 Scatchard plot를 이용하여 binding parameter를 구하였다. 3. 결과 및 고찰 : GA는 Diltiazem의 HSA와 plasma의 결합율에 영향을 미쳤으며, Verapamil의 HSA, LDL, AAG, Plasma 결합율에, 그리고 Nifedipine의 HSA, LDL, Plasma의 단백 결합율에 영향을 주었으며, 각각 n과 Ka값에 변화를 주었다.

• Applied Biological Chemistry
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• v.43 no.4
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• pp.231-235
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• 2000

The changes of calmodulin levels, calmodulin-binding proteins, and $Ca^{2+}$/calmodulin-dependent glutamate decarboxylase during the growth of tobacco suspension cells were investigated. Tobacco cells exhibited a typical growth curve, including an exponential growth phase between 3 and 5 days after inoculation, and an apparent stationary phase occurring after 5 day. Although slight changes were observed from sample to sample, calmodulin protein levels remained similar during the phases of culture growth. Several $Ca^{2+}-dependent$ calmodulin-binding proteins including 56, 46, 36, and 32-kDa proteins were detected in tobacco cell extracts. The 56-kDa protein was identified as glutamate decarboxylase by Western-blot analysis using an anti-GAD monoclonal antibody. The levels of GAD protein and the specific activity of GAD enzyme were highest during the middle exponential phase of the culture growth cycle. These data suggest that $Ca^{2+}$/calmodulin-dependent glutamate decarboxylase is modulated during the growth of tobacco suspension cells.

• Journal of Applied Biological Chemistry
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• v.55 no.4
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• pp.263-266
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• 2012

Isolation of iron and calcium-binding peptides derived from cottonseed meal protein (CMP) hydrolysates was investigated. The degree of hydrolysis of CMP by Flavourzyme was monitored using trinitrobenzenesulfonic acid method and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Enzymatic hydrolysis of CMP for 12 h was sufficient for the preparation of CMP hydrolysates, and the hydrolysates were membrane-filtered under 3 kDa as a molecular weight. The filtered solution was fractionated using Q-Sepharose fast flow, Sephadex G-15, and reversed phase-high performance liquid chromatography for iron and calcium-binding peptides. As a result, F51 fraction was obtained as the best candidate for calcium and iron chelation, and the isolated iron and calcium-binding peptides can be used as functional food additives, similar to iron and calcium supplements.

• Journal of Applied Biological Chemistry
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• v.53 no.3
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• pp.174-178
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• 2010

Calcium and iron binding peptides were prepared by enzymatic hydrolysis and ultrafiltration of rice bran protein (RBP), which was isolated from defatted rice bran by phytase and xylanase treatment and ultrasonication. The isolated RBP had a molecular weight in the range of 10-66 kDa. The extracted proteins were hydrolyzed using Flavourzyme for 6 hr. After ultrafiltration under 5 kDa as molecular weight, the peptides were fractionated into 4 peaks by Sephadex G-15 gel permeation chromatography, and each fraction was determined for calcium and iron binding activity. As the result, Fl and F2 fractions were the best candidate for calcium and iron chelation, respectively. These results suggest that the calcium and iron binding peptides can be used as functional food additives in food industry.

• Journal of Korean Ophthalmic Optics Society
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• v.1 no.2
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• pp.1-6
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• 1996

The most common cause of blindness is cataract. The possible causes, radiation, sugar, drugs, trauma, nutrition, congenital, secondary to eye disease etc. Generally, the opacification of the lens are the result fa oxidation of the lens fibers. The basis for lens transparency is the structural integrity of lens fibers. Opacities were occur if there is a significant amount of high molecular weight protein aggregates. If Ca ions combined with lens ${\alpha}$-crystallin proteins, the lens fibers were aggregated by high molecular weight proteins and the lens were opacified. If Ca ions detached from lens ${\alpha}$-crystallin proteins, the lens fibers were aggregated by low molecular weight proteins and the lens were re-cleared. We need to find out the variety of factors can initiated the process of age-related cataract. And to understanding the mechanism how the various kind, of diabetic cataracts occur.

• Journal of Life Science
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• v.17 no.9 s.89
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• pp.1177-1181
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• 2007

Calmodulin (CaM), a ubiquitous calcium-binding protein, regulates diverse cellular functions by modulating the activity of a variety CaM-binding proteins (CaMBPs). Because eukaryotes have multiple CaMBPs, it is important to isolate and characterize them in different tissues and conditions. So far a number of CaMBPs have been identified through classical screening methods. Many classes of proteins have been predicted to bind CaMs based on their structural homology with already known targets. In an effort to develop a method for large-scale analysis of CaMBPs in Arabidopsis, we have generated a transgenic plants overexpressing AtCaM2-GFP. We performed protein pull-down assay to test whether exogenously expressed AtCaM2-GFP proteins can interact with CaMBPs. The exogenously expressed AtCaM2-GFP could strongly interact with a CaMBP, AS1 protein. This result suggests that AtCaM2-GFP in transgenic plants may interact with many CaMBPs in plant cell. Therefore, we will be able to isolate kinds of CaMBPs by using these transgenic plants in many different tissue and environments.