• Journal of Plant Biology
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• v.33 no.3
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• pp.211-215
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• 1990

There is a family of homologous proteins known to small GTP-inding proteins which have a GTP binding domains and GTPase activity with molecular weight of about 20000 in mammalian tissues. Recently at least 20 different small GTP-binding proteins including three rasproto-oncogene, smg25, rho, and ral gene products were identified. These proteins play a central role in cellular prolifration, neoplasia, signal transduction, terminal differentiation, and secretory process of the cells. In this review, I have briefly compiled current information on the different areas of research in the small GTP-binding proteins in an attempt to convey an overall view of the fundamental role that this family of protein in normal cellular processes. Moreover, furture goals of research in the small GTP-binding proteins as well as the possible existence of this family of proteins in plant cells were discussed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.413-417
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• 2003

To evaluate the antimicrobial activity of green tea against putrefactive microorganism in steamed bread, antibacterial activity of green tea extract against well-known strains of spoilage bacteria (Bacillus subtilis ATCC 6633, Bacillus pulmilus KCTC 3348 and Bacillus cereus IFO 12113) and mold (Aspergillus niger KCCM l1239) in bread was determined using the paper disk method. The green tea extract (GTE) showed the inhibition effects on the growth of all the strains of bacteria and mold at 1, 2, 3% levels. The activity of GTE was stable in the wide range of pH (4~9) and temperature (50~20$0^{\circ}C$). When green tea powder (GTP: 1, 3, 5%) was added to steamed bread increase of total bacterial and mold counts declined during storage at 25"C as the levels of GTP increased. By addition of 5% GTP, mold appeared 1 day late extending shelf life of steamed bread compared to control bread without GTP. Therefore, the levels of GTP added to steamed bread could be more than 5% for extended shelf life and wholesomeness of steamed bread.read.

• Journal of Preventive Medicine and Public Health
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• v.35 no.2
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• pp.169-174
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• 2002

Objective : To investigate gamma-Glutamyltransferase (${\gamma}-GTP$) and its related factors in male industrial workers. Method : Five hundred and tony male workers without heart disease, diabetes mellitus, renal disease, hepatitis, and other liver diseases were surveyed in October 1998. Blood samples were collected to test for ${\gamma}-GTP$, total-cholesterol and fasting blood glucose. A self-administered questionnaire survey on life style was also done. Results : The total geometric mean value of ${\gamma}-GTP$ was 30.6 U/L. According to a univariate analysis: age, BMI(body mass index, $kg/m^2$), alcohol consumption, current smoking, stress, diastolic blood pressure, and blood total cholesterol were significantly associated with ${\gamma}-GTP$(p<0.05). From a multiple regression analysis: BMI, alcohol consumption, current smoking, diastolic blood pressure and total-cholesterol were significantly related to ${\gamma}-GTP$(p<0.05). Coffee consumption was negatively related to ${\gamma}-GTP$, but not significantly. Conclusion : We recommend that a change in health behavior (i.e. reducing alcohol intake, controlling BMI and not smoking) is necessary to decrease ${\gamma}-GTP$ in male workers.

• BMB Reports
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• v.33 no.5
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• pp.391-395
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• 2000

Calexcitin, a calcium-binding protein, was previously cloned and functionally characterized in the squid Loligo pealei. We now report the cloning of a second form of Calexcitin, Calexcitin-2, found in the squid Todarodes pacificus optic lobe. Calexcitin-2 has a significantly different carboxyl terminal region than Calexcitin-1. It lacks the CAAX motif, which is a farnesylation site. The amino acid sequence of Calexcitin-2 shows an 84% identity with Calexcitin-1 and also displays a strong cross immunoreactivity. Western blotting shows that Calexcitin-2 was expressed exclusively in the optic lobe region of squid, but not in other body organs. Regardless of its lack of conserved regions for GTP-binding, Calexcitin-2 shows moderately low affinity GTP-binding and also shows dramatic conformational change induced by GTP-binding. Three possible GTP-binding region mutations, K142A, D144A, and K157A, did not change the G TP binding affinity. This raises the possibility that Calexcitin-2 may have a novel GTP-binding motif.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.12
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• pp.1560-1567
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• 2008

This study was designed to evaluate the effect of green tea products (GTP) on bone metabolism marker in ovariectomized (OVX) rats fed high cholesterol diet. Forty Sprague-Dawley female rats, 10 weeks of age ($279{\pm}2g$), were divided into 4 groups and fed on the experimental diets for 6 weeks: sham operated control (Sham-C) and OVX-control (OVX-C) groups treated high cholesterol diet. OVX-GTP 5% (OVX-G5) and OVX-GTP 20% (OVX-G20) groups were treated with high cholesterol diet containing 5% GTP and 20% GTP, respectively. Food efficient ratio was significantly (p<0.05) lower in OVX-G20 than in the other OVX groups. Bone mineral density of femur was not significantly different among the experimental groups in the order of Sham-C>OVX-G5 and OVX-G20>OVX-C. Alkaline phosphatase activities on serum was lower in the GTP supplement groups than in the OVX-C. Estradiol levels of serum were higher in the GTP supplement groups than in the OVX-C. Osteocalcin levels of serum was the lowest in the OVX-G20. Deoxypyridinoline crosslink values of urine, indicator of bone absorption, was the lowest in the OVX-G20 group. The GTP supplemented groups had a lower bone resorption ratio than in the OVX-C group. From the above results, these findings suggest the possibility of using GTP as a functional food materials related to bone metabolism in menopause.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.81.2-82
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• 2003

Plants have evolved along with pathogens, and they have developed sophisticated defense systems against specific microorganisms to survive. G-protons are considered one of the upstream signaling components working as a key for the defense signal transduction pathway. For activation and inactivation of G-protein, GTP-biding proteins are involved. GTP -binding proteins are found in all organisms. Small GTP-binding proteins, having masses of 21 to 30kD, belong to a superfamily, often named the Ras supefamily because the founding members are encoded by human Ras genes initially discovered as cellular homologs of the viral ras oncogene. Members of this supefamily share several common structural features, including several guanine nucleotide binding domains and an effector binding domain. However, exhibiting a remarkable diversity in both structure and function. They are important molecular switches that cycle between the GDP-bound inactive form into the GTP-bound active form through GDP/GTP replacement. In addition, most GTP-binding proteins cycle between membrane-bound and cytosolic forms. such as the RAC family are cytosolic signal transduction proteins that often are involved in processing of extracellular stimuli. Plant RAC proteins are implicated in regulation of plant cell architecture secondary wall formation, meristem signaling, and defense against pathogens. But their molecular mechanisms and functions are not well known. We isolated a RacB homolog from rice to study its role of defense against pathogens. We introduced the constitutively active and the dominant negative forms of the GTP-hinging protein OsRacB into the wild type rice. The dominant negative foms are using two forms (full-sequence and specific RNA interference with RacB). Employing southern, and protein analysis, we examine to different things between the wild type and the transformed plant. And analyzing biolistic bombardment of onion epidermal cell with GFP-RacB fusion protein revealed association with the nucle.

• The Korean Journal of Food And Nutrition
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• v.19 no.2
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• pp.227-233
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• 2006

The effects of adding green tea powder(GTP) on the quality and storage characteristics of sikhe, Korean traditional sweet rice drink, were studied, The values of sweetness and pH of the sikhe with GTP were $18.40{\sim}18.50%\;and\;5.81{\sim}5.85$, respectively. The L and a values were decreased, but the b value was highly increased when the amounts of GTP were increased. Sensory evaluation showed that color and flavor of sikhe made of GTP were the highest among the treatments. However, sweetness of sikhe with GTP was lowered as the addition of GTP was increased. Sensory attributes such as taste, tenderness, aftertaste and overall acceptability were significantly higher in sikhe perpared with 2% GTP than those of control group(p<0.05). During the storage, pH of the sikhe with GTP was not significantly changed at the nineteenth day of storage, but pH of control group was markedly decreased. The L, a and b values showed no significant changes during storage.

• Journal of Preventive Medicine and Public Health
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• v.30 no.3 s.58
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• pp.518-529
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• 1997

1,281 male subjects who had been examined more than 3 times for regular check-up in one human dock center of the university hospital were studied between 1990-1995, to evaluate the effect of health counselling with life style and $\gamma-GTP$ value between 1054 normal group without intervention and 227 abnormal group with intervention, ages from 30 to 69 years old. Total mean value of $\gamma-GTP$ was $45.7{\pm}40.7$ unit with highest $\gamma-GTP$ value in age group 50-59 on initial examination. Total abnormal rate was 17.7% with the highest abnormal rate of 18.6% in age group 50-59. Initially, the value of $\gamma-GTP$ was significantly different according to the degree of alcohol intake, relative weight and smoking in normal group(p<0.01) not in abnormal group. In conclusion, the value of $\gamma-GTP$ were significantly increasing in normal group without intervention and significantly decreasing in abnormal group with intervention(p<0.05), which suggests the effect of health counselling, such as the recommendation to change the health behaviour.

• Korean Journal of Microbiology
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• v.20 no.4
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• pp.201-209
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• 1982

An enzyme, named GTP cyclohydorlase, that catalizes the hydrolytic removal of carbon No.S of GTP has been partially purified from extracts of Pseudomonas putida (IAM 1506). The enzyme exists in two molecuar weight forms : a high molecular weight form (150,000) and a low molecular weight from (40,000). The high molecular weight form has been purified 25-fold. Some of the properties of the enzyme are as follows : It functions optimally at pH8.0, and at $52^{\circ}C$. The Km value for GTP is $20{\mu}M$. Divalent cations $(Cd^{2+}\;and\;Hg^{2+})$ 2+/) at a concentration of 5mM inhibit completely the enzyme activity. No metal ion including $Mg^{2+}$ is needed for the catalysis. The enzyme is heat labile ; its half at $57^{\circ}C$ is 1.5 min. Of a number of nucleotides tested, only GDP was used to any extent as substrbte in place of GTP. One of the products of the enzyme is determined to be a dihydro-neopterin compound.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.8
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• pp.816-823
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• 2008

This paper describes the test results of developed high speed data processing unit using Xilinx GTP(Multi-Gigabit-Transceiver) interface and DDR-2 memory. The high speed data processing unit receives input data from packet generator at 1.25Gbps and transmits stored data to the data receiving system at 700Mbps. Therefore, DDR-2 memory controller and Xilinx GTP interface are implemented by FPGA instead of CPU to process high speed data directly.