• BMB Reports
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• v.33 no.2
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• pp.188-192
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• 2000

Recombinant protein G has been utilized in the purification of antibodies from various mammalian species based on the interaction of antibodies with protein G. The interaction between immunoglobulin and protein G may not be restricted to the Fc protion of antibodies, as many different $F(ab)_2$ or Fab fragments can also bind to protein G. I found both FAb $F(ab)_2$ of 145-2C11, a hamster anti-mouse $CD3{\varepsilon}$ antibody, bound to the protein G-sepharose. Interestingly, Fab and $F(ab)_2$ of 145-2C11 did not bind to the protein A-sepharose. The binding of Fab and $F(ab)_2$ of 145-2C11 to protein G provided a useful method to remove proteases, chopped fragments of the Fc region, and other contaminating proteins. The remaining intact antibody in the protease reaction mixture can be removed by using a protein A-sepharose, because the Fab and $F(ab)_2$ portions of 145-2C11 did not bind to protein A-sepharose. The specific binding of Fab and $F(ab)_2$ portions of 145-sC11 to a protein G-sepharose (though not to a protein A-sepharose) and binding of intact 145-2C11 to both protein A- and G-sepharose will be useful in developing an effective purification protocol for Fab and $F(ab)_2$ portions of 145-2C11.

• Journal of Nutrition and Health
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• v.44 no.4
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• pp.338-343
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• 2011

This study assessed the current EAR, RDA, and AMDR for protein, which were set in 2005 and revised in 2010 as the DRIs for Koreans. A classical approach to establish the EAR for protein has been the nitrogen balance method. This method has practical limitations and problems in statistical analysis by giving over estimations of nitrogen balance. Thus, the present EAR for protein might be lower than the true requirement. Recent reevaluations of nitrogen balance studies by bilinear regression analysis and the IAAO method have indicated that the EAR of 0.66 g/kg bw/d should be increased by 39% to give 0.92 g/kg bw/d. The AMDR for protein in the Korean DRIs was set at 7-10%, which covers almost the entire population's protein intake. Since the 5th percentile of Korean protein intake is close to 10% of energy and due to the beneficial effects of protein beyond the maintenance of nitrogen equilibrium, the lower range of 7% needs to be increased up to 10%. For practical meal arrangement, 15% of energy as protein, which is close to the average protein intake of Koreans, seems to be proper, although the value is almost two times the EAR.

• Journal of the Korean Home Economics Association
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• v.29 no.3
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• pp.47-59
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• 1991

This study wa performed to investigate the effects of dietary protein and fiber on the lead and protein metabolism in lead poisoning rats. Seventy male rats of Sprague-Dawley strain weighing 172$\pm$2g were blocked into 14 gropus according to body weight. Protein(casein) was given at levels of 15 or 40%, and fibers(pectin, cellulose and CMC) were given at levels of 0, 4 or 10%. The results are summarized as follows: 1. Food intake, weight gain and food efficiency ratio(FER) in groups fed high protein diets were higher than those in low protein groups. Liver weight in groups fed no dietary fiber was higher than that of animals fed fiber. Kidney and femur weights were greater in high protein groups. Tibia and femur lengths, and tibia weight were not significantly different among groups. 2. Hemoglobin content and hematocrit values showed no significant differance with dietary factors. 3. Total protein contents of serum and liver showed no significant difference, but tended to increase with increasing dietary protein level. Both daily urinary and fecal nitrogen excretions in high protein groups were higher than those in low protein groups. Especially daily fecal nitrogen excretions in high dietary fiber groups were significantly high. Body nitrogen absorption rate was the highest in animals fed no fiber. 4. Pb levels in blood, liver, kidney and bone tended to decrease with high dietary protein and fiber levels. Especially Pb level of kidney was high in all groups. Daily urinary Pb excretion showed no significant difference with dietary factors, but fecal Pb excretion increased significantly in high protein and fiber groups.

• Journal of Aquaculture
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• v.13 no.1
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• pp.1-7
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• 2000

The effect of various dietary protein levels on growth and body composition of young common carp raised from 56 g to 170 g in recirculating system was investigated for 15 weeks when they were fed to visual satiety three times daily. Five experiemtal diets were formulated to contain 40, 35, 30, 25 and 21% protein levels and 3.56, 3.59. 3.63, 3.66 and 3.69 kcal/g diet GE levels respectively. Mean survival rates of the fish fed the 40, 35, 30 and 25% protein diets were not different but sig-nificantly higher than that of the fish fed the 40, 35, 30 and 25% protein diets were not different but sig-nificantly higher than that of o the fish fed the 21% protein diet(P<0.05) Weight gain (g/tank) of common carp fed the 30% protein diet was the best. However weight gain of the fish fed the 25, 30, 35 and 40% protein diets were not different but significantly better than that of the fish fed the 21% protein diet. Feed efficiency ratio of the 21% protein diet was significantly lower (P<0.05) than for other groups of diets which were not different among them. Protein efficiency ratio for the 21% protein diet was significantly lower (P<0.05) than for other groups of diets which were not different among them(P>0.05) Dietary protein level had no effect on hemoglobin content in the fish(P>0.05) Crude protein contents of whole body of the fish fed the 35 and 40% protein diets were significantly higher than that of the fish fed the 21$$\mid$% or 25% protein diet(P<0.05) Body crude lipid contents of the fish fed the 21 and 25% protein diets were significantly higher than that of the fish fed the 30% or 35% protein diet. Crude ash contents of the fish fed the 35 and 40% protein diets were significantly higher than that of the fish fed the 21% or 25% protein diet(P<0.05) Moisture content of the fish fed the 35% protein diet was significantly higher than that of the fish fed the 21% protein diet(P<0.05) In considering growth performance of common carp and efficiency of diet dietary protein level could be lowered up to 25% without the reduction of young common carp production in recirculating system.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.12
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• pp.1997-2003
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• 2004

This paper presents a new method and an associated device, capable of detecting protein presence and size from the shift of the mechanical stiffness changing points due to the presence and size of proteins in a nano-gap actuator. Compared to the conventional resonant detection method, the present nanomechanical stiffness detection method shows higher precision for protein detection. The present method also offers simple and inexpensive protein detection devices by removing labeling process and optical components. We design and fabricate the nanomechanical protein detector using an electrothermal actuator with a nano-gap. In the experimental study, we measure the stiffness changing points and their coordinate shift from the devices with and without target proteins. The fabricated device detects the protein presence and the protein size of 14.0$\pm$7.4nm based on the coordinate shift of stiffness changing points. We experimentally verify the protein presence and size detection capability of the nanomechanical protein detector for applications to high-precision biomolecule detection.

• Journal of Microbiology
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• v.33 no.2
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• pp.128-131
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• 1995

Using differential hybridization, we selected the prk gene fortuitously from Schizosaccharomyces pombe homologous to RACK1 of rat which encodes the receptor for activated protein kinase C. The cDNA sequence of prk was determined and its deduced amino acid sequence was 76% homologous to RACK1 and had the feature of trimeric G protein bata subunit. The specific amino acid sequences required for the protein kinase C binding were also present in Prk as in the case of RACK1 protein. From these similarities, we suggest that the Prk is protein kinase C binding protein of S. prombe. The involvement of Prk in signal transduction mediated by protein kinase C remained to be studied.

• Journal of Plant Biology
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• v.39 no.2
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• pp.123-126
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• 1996

The pattern of seed storage protein, vicilin, deposition and site of intracellular localization was examined in cotyledon cells of pea (Pisum sativum) seed using the immunocytochemical methods. The vicilin was confined to the cisternae fo the rough endoplasmic reticulum and dictyosome as well as protein granules newly formed in rough endoplasmic reticulum. Vacuolar protein deposites and protein bodies were also labelled by gold particles. After small protein bodies were formed in the rough endoplasmic reticulum, they were transported to large protein bodies and then fused together. Electron dense protein granule, elaborated in the dictyosome, appears to be transported from dictyosome to protein body. A few unlabelled protein granules seem to be accumulated in other type of proteins than vicilin.

• Journal of Nutrition and Health
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• v.24 no.1
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• pp.20-29
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• 1991

This study was carried out to compare the protein quality of lamb and beef meat. by feeding to growing rats. Sixty weanling rats, 30 males and 30 females, were blocked into 12 groups(6 gruops of males and 6 groups of females). They were fed casein. beef, or lamb as a protein source at two levels, 6 and 15%, for 5 weeks. The amount of food intake. food efficiency ratio, protein efficiency ratio. body weight gain. and the weights of skeletal muscles and liver were measured. Nitrogen retention, protein content in the liver and skeletal muscles, and the levels of protein and cholesterol in the serum were also assayed. Summarzing the results, there were no significant differences between lamb and beef on the growth and nitrogen utilization in the rats fed same percentage of protein diet. However. rats fed 15% protein diet showed significantly higher growth rate than those fed 6%. Therefore, it can be concluded that lamb is as good a protein food as beef in terms of protein quality.

• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.162-166
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• 2004

Phage P22 tailspike is a thermostable homotrimeric protein, and temperature-sensitive folding (tsf) and global suppressor mutations affect its folding yields at elevated temperatures. We earlier suggested that the folding of the tailspike protein in Escherichia coli requires an unidentified molecular chaperone. Accordingly, in the present study, the interactions of purified DnaK, DnaJ, and GrpE heat-shock proteins with the tailspike protein were investigated during the translation and folding of the protein. The cotranslational addition of DnaJ to the tailspike protein resulted in the arrest of folding, when Dnak and GrpE were missing. However, the presence of DnaK, DnaJ, and GrpE had no effect on the folding yield of the tails pike protein, thus, providing evidence for the binding of the nascent tailspike protein with DnaJ protein, a member of DnaK chaperoning cycle.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.212-216
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• 2015

Oseltamivir, also known as Tamifu, is an inhibitor of neuraminidase protein which plays an essential role in proliferation and replication of influenza virus. Binding to the active site of neuraminidase, the oseltamivir prevents the protein from enzyme reaction. Conformational change of the protein(neuraminidase) should be accompanied by the enzyme reaction, but the drug inhibits the protein to deform. In this study, we examine the influence of oseltamivir on protein's conformational change in the structural and mechanical point of view. Finite element analysis of the protein can be an useful approach to investigate the influence of oseltamivir on the deformation of a protein. We suggest the finite element based protein model, and then perform the linear static analysis with the displacement loading condition based on the first two largest motion which can be obtained from the normal mode analysis. The results show that it takes more energy to change shape of the protein with an oseltamivir attached than the protein without an oseltamivir.