• Asian-Australasian Journal of Animal Sciences
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• 제26권3호
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• pp.358-365
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• 2013

A series of in vitro studies were carried out to determine i) the effects of enzyme and formaldehyde treatment on the degradation characteristics of carbohydrate and protein sources and on the synchronicity of these processes, and ii) the effects of synchronizing carbohydrate and protein supply on rumen fermentation and microbial protein synthesis (MPS) in in vitro experiments. Untreated corn (C) and enzyme-treated corn (EC) were combined with soy bean meal with (ES) and without (S) enzyme treatment or formaldehyde treatment (FS). Six experimental feeds (CS, CES, CFS, ECS, ECES and ECFS) with different synchrony indices were prepared. Highly synchronous diets had the greatest dry matter (DM) digestibility when untreated corn was used. However, the degree of synchronicity did not influence DM digestibility when EC was mixed with various soybean meals. At time points of 12 h and 24 h of incubation, EC-containing diets showed lower ammonia-N concentrations than those of C-containing diets, irrespective of the degree of synchronicity, indicating that more efficient utilization of ammonia-N for MPS was achieved by ruminal microorganisms when EC was offered as a carbohydrate source. Within C-containing treatments, the purine base concentration increased as the diets were more synchronized. This effect was not observed when EC was offered. There were significant effects on VFA concentration of both C and S treatments and their interactions. Similar to purine concentrations, total VFA production and individual VFA concentration in the groups containing EC as an energy source was higher than those of other groups (CS, CES and CFS). The results of the present study suggested that the availability of energy or the protein source are the most limiting factors for rumen fermentation and MPS, rather than the degree of synchronicity.

• 한국양식학회지
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• 제6권1호
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• pp.47-53
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• 1993

새로운 양식 대상종으로 메기의 생산량 증가를 위하여 사료 중 최적 단백질 함량을 설정 하고자 실험한 결과는 다음과 같다. 평균 체중 약 7g되는 메기 치어의 체중은 사료중 단백질 함량 $25\%\~55\%$ 사이에서 단백질 함량이 높은 사료를 공급할수록 증가하였으나, 근육 단백질의 증가는 $45\%$ 부근에서 최고치에 달하였으며, 그 이상으로 사료 단백질 함량을 증가시켜도 변화가 없었다. 단백질 효율 및 정미단백 이용율은 $25\%$ 부근에서 최고치에 달했지만 $45\%$ 부근에서 일시적으로 증가하여 단백질 함량 $45\%$ 실험구가 가장 양호한 것으로 나타났다. 따라서 멸치분을 단백질 원으로 하였을 때 메기 치어 사료의 최적 단백질 함량은 $45\%$로 사료된다.

• 동아시아식생활학회지
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• 제7권2호
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• pp.153-158
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• 1997

This study was designed to find out the effects of soybean protein and milk protein between nondiabetic and diabetic rats. The experimental results are summarized as follows. 1. Total food intake was higher in diabetic soybean protein group than other groups but it was not significant. 2. The change of body weight was lower in diabetic soybean protein group than other groups and the soybean protein was effective to maintain the ideal body weight. 3. The effects of lowering total cholesterol and glucose in serum was higher in soybean protein groups than the milk protein groups.

• Asian-Australasian Journal of Animal Sciences
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• 제13권3호
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• pp.317-322
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• 2000

In situ and in vivo digestion trials were conducted to determine the degradation of dry matter (DM), crude protein (CP) and effective protein degtadability (EPD), and digestibility of nutrients of Hazelnut kernel oil meal (HKOM), and effects of HKOM on nitrogen (N) balance. In the in situ study, nylon bag were suspended in the rumen of 3 Karayaka rams to estimate protected protein. Protein sources were analyzed for pepsin soluble protein (PSP) using a Pepsin Digestion Method. In the digestion trials, 4 Karayaka rams (36 mo.) were used in a $4{\times}4$ Latin square to evaluate the digestibility of nutrients and N retention to measure effects of diets containing HKOM, soybean meal (SBM) corn gluten meal (CGM) and urea (U). The degradability of DM and CP, and PSP content of HKOM were lower (p>0.05) than that of SBM, but higher (p<0.001) than that of CGM. EPD of HKOM was higher (p<0.01) than that of SBM or CGM. The apparent digestion coefficients of organic matter and CP for HKOM were lower than for SBM, but higher than for CGM. N retention of HKOM was higher than that of SBM and lower than that of CGM (p>0.05). In conclusion, these data may indicate that the HKOM is a high digestible feed source with a value between SBM and CGM.

• 미생물학회지
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• 제29권5호
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• pp.270-277
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• 1991

A mutational alteration in the signal sequence of ribose-binding protein (RBP) of Escherichia coli, rbsB103, completely blocks the export of the protein to the periplasm. Intragenic suppressors for this mutation have been selected on minimal medium with ribose as a sole carbon source. Six suppressor mutations were characterized in detail and were found to have single amino acid wubstitution in the mature portion of RBP, which resulted in the mobility shift of the proteins on SDS polyacrylamide gel. Amino acid changes of these suppressors were localized in several peptides which are packed to form the N terminal domain of typical bilobate conformation of RBP. The involvement of SecB, a molecular chaperone, was investigated in the suppression of signal sequence mutation. Translocation efficency was found to be increased by the presence of SecB for all suppressors. It is likely that the folding characteristics of RBP altered by the suppressor mutations affect the affinity of interaction between SecB and RBP.

• Bulletin of the Korean Chemical Society
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• 제25권11호
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• pp.1676-1680
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• 2004

We demonstrate that wide-angle X-ray scattering pattern from photoactive yellow protein (PYP) in solution using a high flux third generation synchrotron X-ray source reflects not only the overall structure, but also fine structures of the protein. X-ray scattering data from PYP in solution have been collected in q ranges from 0.02 ${\AA}^{-1}$ to 2.8 ${\AA}^{-1}$. These data are sensitive to the protein structure and consistent with the calculation based on known crystallographic atomic coordinates. Theoretical scattering patterns were also calculated for the intermediates during the photocycle of PYP to estimate the feasibility of time-resolved wide-angle X-ray scattering experiments on such proteins. These results demonstrate the possibility of using the wide-angle solution X-ray scattering as a quantitative monitor of photo-induced structural changes in PYP.

• Journal of Microbiology and Biotechnology
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• 제17권12호
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• pp.1949-1954
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• 2007

A simple way to prevent protein hyperglycosylation in Hansenula polymorpha was found. When glucose oxidase from Aspergillus niger and carboxymethyl cellulase from Bacillus subtilis were expressed under the control of an inducible methanol oxidase (MOX) promoter using methanol as a carbon source, hyperglycosylated forms occurred. In contrast, MOX-repressing carbon sources (e.g., glucose, sorbitol, and glycerol) greatly reduced the extent of hyperglycosylation. Carbon source starvation of the cells also reduced the level of glycosylation, which was reversed to hyperglycosylation by the resumption of cell growth. It was concluded that the proteins expressed under actively growing conditions are produced as hyperglycosylated forms, whereas those under slow or nongrowing conditions are as short-glycosylated forms. The prevention of hyperglycosylation in the Hansenula polymorpha expression system constitutes an additional advantage over the traditional Saccharomyces cerevisiae system in recombinant production of glycosylated proteins.

• KSBB Journal
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• 제13권3호
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• pp.325-330
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• 1998

The methylotrophic yeast, Pichia pastoris, is known to be a potential host to offer many advantages for production of recombinant proteins. Fermentation parameters were optimized to enhance the heterologous ${\beta}$-galactosidase productivity with P. pastoris. Optimum concentration of methanol, used as inducer, was observed to be 8 g/L and the extent of repression of AOX1 promoter by glycerol was lower than by glucose. The degradation of the gene product ${\beta}$-galactosidase by protease was inhibited as the pH increased from 5 to 8 and the yeast extract(1%) as nitrogen source increased expression level 4 times higher compared to yeast nitrogen base(1%) as nitrogen source increased expression level 4 times higher compared to yeast nitrogen base(1%). Induction method, in which methanol is just added to fermentation medium without centrifugation, was found to be as much effective as the one with centrifugation.

• 한국전기전자재료학회논문지
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• 제17권4호
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• pp.404-409
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• 2004

We fabricated photo-sensor for fluorescence detection in LOC. LOC is high throughput screening system. Our LOC screens biochemical reaction of protein using the immunoassay, and converts biochemical reaction into electrical signal using LIF(Laser Induced Fluorescence) detection method. Protein is labeled with rhodamine intercalating dye and finger PIN photodiode is used as photo-sensor We measured fluorescence emission of rhodamine dye and analyzed tendency of fluorescence detection, according to photo-sensor size, light intensity, and rhodamine concentration. Detection current was almost linearly proportional to two parameters, intensity and concentration, and was inversely proportional to photo-sensor size. Integrated LOC consists of optical-filter deposited photo-sensor and PDMS microchannel detected 50 (pg/${mu}ell$) rhodamine. For integrated LOC including light source, we used green LED as the light source and measured emitted fluorescence.

• Journal of Plant Biology
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• 제29권3호
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• pp.145-156
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• 1986

The excretion of ammonia and glutamine synthetase activities were measured in aposymbiotic Paramecium and symbiotic Paramecium. The uptake of nitrate and ammonia, and specific enzyme activities of nitrate reductase, glutamate dehydrogenase and glutamine synthetase were investigated in symbiotic Chlorella from Paramecium bursaria and Chlorella ellipsoidea. The ammonia concentration in the culture media of aposymbiotic Paramecium was increased according to the growth of the Paramecium but it was not changed in symbiotic Paramecium. Nitrate, the major nitrogen source, was taken up at a rate of 0.635 nmol/ 106 Chlorella/hr in Chlorella ellipsoidea. Most of ammonia was assimilated to glutamine by glutamine synthetase, of which acitivty was 1,467 $\mu$mol/mg protein/min in Chlorella elliposidea. Contrary to Chlorella ellipsoidea, ammonia and glutamine transported from the Paramecium were the nitrogen source of symbiotic Chlorella and ammonia was taken up at a rate of 3.854 nmo./106 Chlorella/hr into synmbiotic Chlorella. Most of ammonia were assimilated to glutamate by glutamate dehydrogenase in symbiotic Chlorella. The glutamate dehydrogenase (GDH/NADH) activity was 0.851 $\mu$mol/mg protein/min.