• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.6
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• pp.801-806
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• 2009

A species producing transglutaminase (EC 2.3.2.13) was isolated from forest soil and identified as Streptomyces platensis YK-2. The transglutaminase was purified from culture broth by 50% methanol precipitation, followed by successive chromatography on DEAE-Sephadex. The yield and purification-fold was 63.4% and 2.2-fold, respectively. The purified microbial transglutaminase (MTG) migrated as a single band of approximately 45 kDa upon sodium dodecyl sulfate polyacrylamide gel eletrophoresis. The isoelectric point determined by multichambered electrofocusing was pH $6.0{\sim}7.0$. The enzyme was strongly inhibited by $Hg^{++}$, but was activated by $Cd^{++}$, $Mg^{++}$, $Mn^{++}$, $Pb^{++}$ and reducing agents such as dithiothreitol and mercaptoethanol.

• Toxicological Research
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• v.32 no.3
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• pp.239-243
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• 2016

Propolis is a multicomponent, active, complex resinous substance collected by honeybees from a variety of plant sources. We have studied the effect of propolis on neurite outgrowth of SH-SY5Y human neuroblastoma cells induced to differentiate by all-trans-retinoic acid (RA). Propolis, at a concentration of $3{\mu}g/mL$, had no significant effect on the viability of differentiating SH-SY5Y cells. However, the neurite outgrowth of the differentiating SH-SY5Y cells treated with propolis ($0.3{\sim}3{\mu}g/mL$) for 48 hr was significantly inhibited in a dose-dependent manner. Treatment of RA-stimulated differentiating SH-SY5Y cells with 0.3 to $3{\mu}g/mL$ propolis resulted in decreased level of transglutaminase and 43-kDa growth-associated protein (GAP-43) in a dose-dependent manner. The results indicate that propolis is able to inhibit neurite outgrowth of differentiating SH-SY5Y cells.

• BMB Reports
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• v.34 no.2
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• pp.95-101
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• 2001

Tissue transglutaminase (TGII, $G{\alpha}h$) belongs to a family of enzymes which catalyze post-translational modification of proteins by forming isopeptides via $Ca^{2+}$-dependent reaction. Although TGII-mediated formation of isopeptides has been implicated to play a role in a variety of cellular processes, the physiological function of TGII remains unclear. In addition to this Tease activity, TGII is a guanosine triphosphatase (GTPase) which binds and hydrolyzes GTP It is now well recognized that the GTPase action of TGII regulates a receptor-mediated transmembrane signaling, functioning as a signal transducer of the receptor. This TGII function signifies that TGII is a new class of GTP-binding regulatory protein (G-protein) that differs from "Classical" heterotrimeric G-proteins. Regulation of enzyme is an important biological process for maintaining cell integrity. This review summarizes the recent development in regulation of TGII that may help for the better understanding of this unique enzyme. Since activation and inactivation of GTPase of TGII are similar to the heterotrimeric G-proteins, the regulation of heterotrimeric G-protein in the transmembrane signaling is also discussed.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2006.05a
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• pp.170-174
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• 2006

근육 단백질과 우유 단백질간의 상호작용의 촉매제로써 TGase의 최적화를 위한 온도와 배양시간을 결정하고자 본 실험을 실시하였다. 돼지 등심에서 근원섬유 단백질을 추출하였고 배양온도는 4, $37^{\circ}C$로, 배양시간은 0, 0.5, 2, 4시간으로 설정하였다. 단백질의 열량분석, 점도, 겔 강도, 단백질 밴드의 변화를 측정하였으며, 그 결과 단백질 열량 변화는 각 단백질 별로 열량 변화 패턴이 상이하게 나타났으며 근원섬유와 카제인 염의 혼합액은 각각의 단백질의 피크와 유사하게 나타났고 배양시간과 온도에 따라 차이를 보여 $4^{\circ}C$에 비하여 $37^{\circ}C$에서 열량 변화가 크게 나타났다. 점도의 경우 배양하지 않은 것과 비교했을 때 $37^{\circ}C$에서 2시간 배양했을 때부터 유의적인 차이를 보이며 증가했으나 4시간 배양한 것과는 차이를 나타내지 않았다. 전기영동의 경우에도 $37^{\circ}C$에서 30분 배양한 처리구는 큰 변화를 나타내지 않았으나 2시간부터 저분자의 밴드가 소멸되고 고분자의 biopolymer를 형성되었다.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.321-326
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• 2003

The objectives of this study were to develop restructured meat products(RMPs) using a transgluta-minase(TGase) and to improve the textural characteristics of RMPs manufactured with pale, soft, exudative(PSE) pork hams. The pH values of RMPs with PSE and normal pork were 5.94 and 6.07, respectively, and their water activity value was approximately 0.981. The RMPs had 70∼72％ moisture, 4∼5％ fat, 19∼20％ protein, and approximately 3％ ash contents. No differences in pH, water activity, chemical composition, and hunter color values were observed between RMPs manufactured with normal and PSE pork(p＞0.05). However, RMPs containing PSE pork hams had higher drip loss(％)(p＞0.05) than those with normal pork hams after 10 days of refrigerated storage. Although no differences were observed in the texture profile analysis(TPA) hardness and sensory evaluation, RMPs with PSE pork hams tended to have more pores and lower binding capacity those with normal pork. This result indicated that additional substrates or longer tumbling time(＞4 hr) for the manufacture of RMPs containing PSE pork were required for the products to have similar palatability to those with normal pork.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1152-1157
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• 1998

In this study, an attempt was made to obtain the optimum setting condition of frozen mackerel surimi prepared from alkaline washing under atmospheric, 660 and 560 mmHg pressure. Mackerel surimi were incubated at 15, 25, 35 and $45^{\circ}C$ for 2, 4, 6, 8 and 10 hr, respectively, followed by heating at $90^{\circ}C$ for 25 min to be cooked gel. The qualities of surimi gels were examined by analyzing the transglutaminase (TGase) activity, gel strength and scanning electron microscopy (SEM). For the preparation of mackerel surimi gel, optimum condition of setting was incubation at $35^{\circ}C$ for 6 hr.

• Molecules and Cells
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• v.21 no.1
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• pp.121-128
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• 2006

Maitotoxin (MTX) is known as one of the most potent marine toxins involved in Ciguatera poisoning, but intracellular signaling pathways caused by MTX was not fully understood. Thus, we have investigated whether intracellular reactive oxygen species (ROS) are involved in MTX-induced cellular responses in human umbilical vein endothelial cells. MTX induced a dose-dependent increase of intracellular [$Ca^{2+}$]. MTX stimulated the production of intracellular ROS in a dose- and time-dependent manner, which was suppressed by BAPTA-AM, an intracellular $Ca^{2+}$ chelator. Ionomycin also elevated the ROS production in a dose-dependent manner. MTX elevated transamidation activity in a time-dependent manner and the activation was largely inhibited by transfection of tissue transglutaminase siRNA. The activation of tissue transglutaminase and ERK1/2 by MTX was suppressed by BAPTA-AM or ROS scavengers. In addition, MTX-induced cell death was significantly delayed by BAPTA-AM or a ROS scavenger. These results suggest that [$Ca^{2+}$]-dependent generation of intracellular ROS, at least in part, play an important role in MTX-stimulated cellular responses, such as activation of tTGase, ERK phosphorylation, and induction of cell death, in human umbilical vein endothelial cells.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.1
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• pp.19-26
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• 2006

Objective: In order to elucidate the retrogressive degeneration of orofacial cleft, the fissured tissues of prenatal and postnatal cleft lip and palate were examined by histological and immunohistochemical methods. Design: Totally 42 cases of prenatal (n=17) and postnatal (n=25) cleft lip and/or palate were examined in comparison with 10 cases of normal lip and oral mucosa using immunohistochemical stainings of MMP-3, MMP-9, MMP-10, cathepsin G, PCNA, E-cadherin, TGase 2, HSP-70, vWF, and VEGF. Main Outcome Measures: In the fissured tissue the sebaceous glands were strongly positive for PCNA and grew into the underlying fibromuscular tissue (24/42). Some hyperplastic sebaceous glands of prenatal cleft lip produced infundibular follicular cyst (9/17). The skin and mucosal epithelia from the postnatal cleft lip and palate (10/25) showed severe basal hyperplasia (11/25) and melanocyte infiltration (7/25). Results: The immunostaining of MMP-3 and HSP-70 were strongly positive in the hyperplastic sebaceous glands and nearby atrophying muscle bundles of the fissured tissue, while MMP-9, MMP-10, and cathepsin G were almost negative. The immunoreactions of the other antibodies used in this study were similar between in the fissured tissues and in the normal controls. Conclusions: These data suggest that the over-expression of MMP-3 is closely related to the sebaceous gland hyperplasia, epithelial dysplasia, and the muscle degeneration, and that the over-expression of MMP-3 in the fissured tissue may continuously aggravate the cleft condition in the later life.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1166-1173
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• 2014

This study investigated the detoxification effects of enzymatic hydrolysate from oyster on acetaminophen-induced toxicity using HepG-2 cells. Oyster hydrolysate was made with 1% Protamex and 1% Neutrase after treatment with transglutaminase (TGPN) or without (PN). Two types of oyster hydrolysate were added to human-derived HepG-2 hepatocytes damaged by acetaminophen, after which the survival rate of HepG-2 cell was measured. In addition, glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) activities in the culture media were evaluated. The survival rates of HepG-2 cells were $136.2{\pm}1.4%$ at $100{\mu}g/mL$ of TGPN and $179.6{\pm}3.8%$ at $200{\mu}g/mL$ of TGPN. These cell survival rates were higher compared to that of the negative control group ($60.7{\pm}3.2%$) treated only with acetaminophen. GOT activity was $38.3{\pm}0.2$ Karmen/mL in the negative control group, whereas it was $19.9{\pm}0.5$ for TGPN ($200{\mu}g/mL$) and $22.0{\pm}2.4$ Karmen/mL for PN ($200{\mu}g/mL$). GOT and GTP activities were shown to be dependent on TGPN concentration, and significant reduction in activities could be conformed. The detoxification efficacy of TGPN was higher compared to that of PN. These results suggest that oyster hydrolysate has potential as a healthy food or pro-drug for liver protection.