• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.1
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• pp.29-38
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• 1972

The protein composition of abalone muscle was estimated with the following result: on a series of samples analyzed, water-soluble protein, $19\~22\%$, salt-soluble protein, $27\~39\%$: alkali-soluble protein, $20\~26\%$ : and stroma $20\~28\%$ : respectively. It was demonstrated by ultracentrifugal analysis that approximately $65\%$ of the salt-soluble protein is accounted for by paramyosin, $30\%$ by actomyosin, and $5\%$ by myosin, respectively. The ultracentrifugally homogenous paramyosin was prepared by BAILEY's ethanol-dried method. It showed a $S^{\circ}\;_{20,\;{\omega}$ of 3.14s, and was completely salted in with KCl beyond $0.35{\mu}$. The intrinsic viscosity at $25^{\circ}C$ was estimated at 3.1. The paramyosin is rich in several amino acids such as arginine, aspartic acid, glutamic acid, etc., and lacking of both proline and tryptophane, in rough accord with other paramyosins reported. The abalone paramyosin did not show ATPase activity over a pH range of 5 to 9,5 even in the presence of Ca++ or Mg++. So was the case with the paramyosin specimen prepared by BAILEY's wet-extraction method.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.26 no.2
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• pp.133-140
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• 1993

In order to obtain the fundamental factors influencing on gelation of Alaska pollack meat paste during processing, the interactions among hydrophobic residues, disulfide bonds and gel strength were investigated. Hydrophobic interactions between actomyosin molecules were strengthened when the temperature was raised from $5^{\circ}C\;to\;65^{\circ}C$, especially between the range from $25^{\circ}C\;to\;35^{\circ}C$. Total SH groups were decreased at the higher heating temperature and the severe decreasing occurred from $45^{\circ}C$. However the amounts of free SH groups were increased significantly over $45^{\circ}C$.

• Journal of Korean Physical Therapy Science
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• v.11 no.1
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• pp.20-27
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• 2004

It is widely accepted that smooth muscle contraction is triggered by intracellular $Ca^{2+}$ ($[Ca^{2+}]_i$) released from intracellular $Ca^{2+}$ stores such as sarcoplasmic reticulum (SR) and from the extracellular space, The increased $[Ca^{2+}]_i$ can phosphorylate the 20-kDa myosin light chain ($MLC_{20}$) by activating MLC kinase (MLCK), and this initiates smooth muscle contraction. In addition to the $[Ca^{2+}]_i$-MLCK-tension pathway, a number of intracellular signal molecules, including mitogen-activated protein kinase (MAPK), protein kinase C (PKC), phosphatidylinositol 3-kinase (PI3K), and Rho-associated coiled coil-forming protein kinase (ROCK), play important roles in the regulation of smooth muscle contraction. However, the mechanisms regulating contraction of caldesmon (CaD), actin-binding protein, are not entirely elucidated in the presence of $Ca^{2+}$. It is known that CaD tightly interacts with actin and inhibits actomyosin ATPase activity. Therefore, the purpose of the present study was to investigate the roles of $Ca^{2+}$-dependent CaD in smooth muscle contraction. Endothelin-1 (ET-1), G-protein coupled receptor agonist and vasoconstrictor, increased both vascular smooth contraction and phosphorylation of CaD in the presence of $Ca^{2+}$. These results suggest that ET-1 induces contraction and phosphorylation of CaD in rat aortic smooth muscle, which may he mediated by the increase of $[Ca^{2+}]_i$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.6
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• pp.829-834
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• 1998

It is well known that the native conformation of many proteins can be stabilized by carbohydrates or polyalcohols. However, the mechanism of the stabilization still remains unclear. In the present studies, to characterize the cryoprotective mechanism of corn starch enzyme hydrolysates on fish protin, solubility of hydrolysates, thermal behavior of hydrolysates and actomyosin solution, and enzyme kinetics in frozen system were investigated. The solubility of the hydrolysates increased with the increase in D.E. value. The $T_g^{'}$ of the hydrolysates were linearly correlated with D.E. value and the T-g value of the hydrolysates (D.E. 5,10,15,20) were reported to be $-7.2^{\circ}C\;-8.8^{\circ}C\;-11.9^{\circ}C$, and $-14.3^{\circ}C$, respectively. The results of enzyme experiments showed that the higher the D.E. value, the higher was the rate of reaction in frozen storage ($-12^{\circ}C$). It is found to support the cryostabilization mechanism that the hydrolysats act to enmesh the protein in a glass state where all deteriorative processes are greatly slowed down.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.574-578
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• 2001

Myofibrillar proteins were prepared from red muscle and white muscle of fresh water fish and sea water fish, and their thermostabilities and effect of temperature on the myofibrillar ATPase activities were compared. Differences in temperature dependency of myofibrillar ATPase activities were found between two species. Thermodynamic data for inactivation of myofibrillar proteins, such as D value, Z value, $\Delta$ $H^{{\neq}}$, $\Delta$ $G^{{\neq}}$ and $\Delta$ $S^{\neq}$ revealed that thermostabilities of myofibrillar proteins from fresh water fish were higher than those from sea water fish, and that myofibrillar proteins from red muscle were more heat labile than those from white muscle.

• Korean Journal of Food Science and Technology
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• v.18 no.3
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• pp.226-233
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• 1986

Myofibrillar proteins were prepared from red muscle and white muscle, and their thermostabilities were compared. Rate constants of inactivation of myofibrillar proteins were increased as the ionic strength of reaction mixture increased and also dielectric constant of reaction mixture decreased. Thermodynamic data forinactivation of myofibrillar proteins, such as $D-value,\;{\Delta}H^{\ddag},\;{\Delta}G{\ddag}\;and\;{\Delta}S^{\ddag$, revealed that thermostabilities of myofibrillar proteins from white muscle were higher than those from red muscle, and that myofibrillar proteins from chicken muscle were more heatlabile than from bovine muscle.

• Journal of Biomedical Engineering Research
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• v.40 no.1
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• pp.1-6
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• 2019

Human mesenchymal stem cells (hMSC) are multipotent stromal cells that have great potential to differentiate into a variety of cell types such as osteocytes, chondrocytes, and myocytes. Although there have been many studies on their clinical availability, little is known about how intracellular signals can be modulated by topographic features of the extracellular matrix (ECM). In this study, we investigated whether and how microwavy-patterned extracellular matrix (ECM) could affect the signaling activity of focal adhesion kinase (FAK), a key cellular adhesion protein. The fluorescence resonance energy transfer (FRET)-based FAK biosensor-transfected cells are incubated on microwavy-patterned surfaces and then platelet derived growth factor (PDGF) are treated to trigger FAK signals, followed by monitoring through live-cell FRET imaging in real time. As a result, we report that PDGF-induced FAK was highly activated in cells cultured on microwavy-patterned surface with L or M type, while inhibited by H type-patterned surface. In further studies, PDGF-induced FAK signals are regulated by functional support of actin filaments, microtubules, myosin-related proteins, suggesting that PDGF-induced FAK signals in hMSC upon microwavy surfaces are dependent on cytoskeleton (CSK)-actomyosin networks. Thus, our findings not only provide new insight on molecular mechanisms on how FAK signals can be regulated by distinct topographical cues of the ECM, but also may offer advantages in potential applications for regenerative medicine and tissue engineering.

• Journal of the Korean Society of Food Science and Nutrition
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• v.2 no.1
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• pp.1-21
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• 1973

The muscle of abalone, Notohaliotis discus (REEVE), and top-shell, Turbo cornutus Solander, were examined for protein composition. Then paramyosins which are known as one of the important structural protein of the muscle fibrils were isolated from the both muscle and their physico-chemical properties such as solubility, salting-out behaviour, intrinsic viscosity, ATPase activity, etc. involving amino acid composition and N-terminal amino acid residues were investigated to elucidate phylogenie characteristics more intensively from the viewpoint of comparative biochemistry. The analysis of protein composition resulted in the following estimations: abalone muscle; water-soluble protein of 22 %, salt-soluble protein, 34%, alkali-soluble protein, 20%, and stroma protein, 24%, and top-shell muscle; water-soluble protein of 16%, salt-soluble protein, 30%, alkali-soluble protein, 29%, and stroma protein, 25%, respectively. It is demonstrated in sedimentation analysis that paramyosin and myosin-actomyosin account for approximately 65% and 35% of the salt-soluble protein of abalone, and that the composition of both sediments in top-shell was approximately 70% and 30%, respectively. The ultracentrifugally homogenous paramyosins isolated essentially according to Bailey's ethanol-dried method from both of the muscle showed a $S^{\circ}_{20,w}$ of 3. 14s for abalone and a $S^{\circ}_{20,w}$ of 3.50s for top-shell. The both paramyosins were commonly rich in arginine, aspartic acid, and glutamic acid, while scarcely contained proline and tryptophan, in rough accord with the other paramyosins thus far reported. It is clear that these gastropod paramyosins showed of having the characteristic N-terminal amino acid residues such as N-aspartic acid, N-valine, N-serine, and N-threonine in common. The abalone paramyosin completely salted in with KCl beyond $0.35{\mu}$ and the top-shell paramyosin beyond $0.30{\mu}$. The abalone paramyosin was salted-out between 18% and 30% saturation of ammonium sulphate and the top-shell paramyosin between 22% and 29% saturation. The intrinsic viscosities at abalone and top-shell paramyosins at $25^{\circ}C$ were estimated respectively to be 3.1 dl/g and 2.6 dl/g showing somewhat higher than the values for some other paramyosins from lamellibranchs. In regard with the ATPase activity, the para myosin specimens did not exhibit any significant activity over through the pH conditions of 5 to 9.5. irrespective of the presence of $Ca^{++}$ or $Mg^{++}$. So was the case with the abalone paramyosin prepared by a slightly modified Bailey's wet-extraction method.

• Journal of Life Science
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• v.14 no.5
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• pp.770-777
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• 2004

It has been previously reported that unacetylated a-tropomyosin(TM) produced in E. coli failed to bind to actin while acetylated muscle TM and Ala-Ser dipeptide fusion TM (AS-TM) bound well to actin. In order to determine the structural requirement of the amino terminus for high actin affinity, a recombinant tropomyosin (Ala-TM) that a single Ala residue was added to the amino terminus of Ala-TM was constructed, overexpressed, and purified from E. coli. Actin affinity of Ala-TM was 2.3$\times$$10^{6}$$M^{-1}$, whereas that of unacetylated TM was considerably lower than 0.1$\times$$10^{-6}$$M^{-1}$ indicating that addition of a single Ala residue to the amino terminus drastically increased, at least twenty times, actin affinity of TM. Ala-TM, however, bound to actin about three times weaker than acetylated TM and AS- TM, implying that the addition of an Ala residue was insufficient for complete restoration of high actin affinity. While Ala-TM, AS-TM, and muscle TM showed inhibition and activation of actomyosin Sl ATPase activity depending on myosin Sl concentration, the degree of inhibition and activation was different from each other. AS-TM exhibited the greatest inhibition of the ATPase at low Sl concentration, whereas the greatest activation of the ATPase was observed with muscle TM. These results, together with previous findings, strongly suggested that local structure of the amino terminus is the crucial functional determinant of TM.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1120-1127
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• 1998

An attempt was made in this study to investigate the optimum condition of washing for preparation of mackerel surimi by alkaline washing of 1, 3, 5, and 7 times under atmospheric (760), 660, and 560 mmHg pressure. The qualities of surimis were examined by analyzing the factors such as water content, crude lipid, pH, volatile basic nitrogen (VBN), expressible drip, protein extractability, $Mg^{2+}-$, $Ca^{2+}-$ and EDTA-ATPase activity, transglutaminase (TGase) activity, gel strength and color. The contents of moisture, crude lipid, pH and VBN in surimis prepared by alkaline washing under atmospheric, and reduced pressure went up to $72.0{\sim}72.9%$, $4.8{\sim}5.7%$, $6.9{\sim}7.0$ and $6.7{\sim}7.0\;mg/100\;g$, respectively. Protein extractability, ATPase activity and TGase activity were highest in surimis prepared by alkaline washing under 560 mmHg. Gel strengths of surimi setting gel and cooked gel from five times washing under 560 mmHg were 420 g cm (atmospheric, 330 g cm) and 485 g cm (atmospheric, 412 g cm), respectively. For the preparation of mackerel surimi, optimum washing condition was five times washing under 560 mmHg.