• 한국가금학회지
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• 제35권4호
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• pp.381-389
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• 2009

본 연구는 아미노산 소화율과 육계의 생산성에 대하여 CDDGS의 효과를 평가하기 위해 실시하였다. <시험 1> CDDGS의 $TME_n$가는 $2,937{\pm}50.1\;kcal/kg$ 이었다. <시험 2> 공시계는 1일령 Ross종 육계 192수를 CDDGS 첨가 수준에 따라 총 4처리구, 처리당 4반복, 반복당 12수씩 완전 임의 배치하였다. 시험 사료는 육계 초기($0{\sim}2$주), 전기($2{\sim}4$주)와 후기($4{\sim}6$)의 기본 사료에 CDDGS를 0, 6, 12, 18% 첨가하였으며, ME가와 CP는 일정하게 유지하였다. 증체량에는 큰 차이가 없었으나, 섭취량은 CDDGS 비급여구가 급여구보다 증가하였다(P<0.05). CDDGS 처리구에서 인의 소화율이 크게 증가하였으며, 아미노산 소화율은 CDDGS 첨가구가 대조구에 비해 lysine, threonine, aspartic acid 및 glycine에서 낮게 나타났다(P<0.05). 이상의 결과로부터, CDDGS는 높은 ME가를 가지고 있으며, CDDGS 첨가구는 대조구에 비해 아미노산 소화율이 낮았으나, 육계 생산성에는 크게 영향을 미치지 않았다.

• 생명과학회지
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• 제23권2호
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• pp.324-331
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• 2013

O-GlcNAc 화(O-GlcNAcylation)는 단백질의 serine이나 threonine에 N-acetylglucosamine (GlcNAc) 분자가 결합하는 것으로, 기존의 당단백질과 달리 세포질 및 핵단백질 모두에 일어난다. 또한 수정의 속도가 빠르고 가역적으로 일어남이 인산화 수식과 유사하다. 그러나 수많은 인산화효소와 탈인산화효소가 관여하는 것과 달리 O-GlcNAc 수식은 O-GlcNAc transferase (OGT)와 O-GlcNAcase (OGA) 단 두 개의 효소에 의하여 이루어진다. 이러한 단순한 조절기전은 세포가 내외환경에 즉시 적응할 수 있도록 진화한 것으로 해석된다. 즉, O-GlcNAc 수식은 특정한 단백질 하나 하나의 활성을 켜거나 끄는 것이 아니라, 세포의 신호전달과정의 효율을 전반적으로 조절하는 '가변저항기(rheostat)' 역할을 한다. O-GlcNAc 수식은 흔히 같은 아미노산 혹은 그 주변의 아미노산이 인산화되는 것을 수반하는데, 이는 인산화와 함께 서로 조화를 이루어 세포활성을 조절하는 것으로 해석된다. 최근 O-GlcNAc이 더 나아가 O-GlcNAc-P로 인산화될 가능성이 제시되고 있는 바, 본 총설에서는 이의 가능성을 이론적으로 설명하고, 실제 실험결과를 소개한다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권3호
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• pp.394-402
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• 2003

Individual and combined supplementation of phosphorus-adequate, wheat-based broiler diets with exogenous phytase and xylanase was evaluated in three experiments. The effects of the enzyme combination in lysine-eficient diets containing wheat and sorghum were more pronounced than those of the individual feed enzymes. The inclusion of phytase plus xylanase improved (p<0.05) weight gains (7.3%) and feed efficiency (7.0%) of broilers (7-28 days post-hatch) and apparent metabolisable energy (AME) by 0.76 MJ/kg DM. Phytase plus xylanase increased (p<0.05) the overall, apparent ileal digestibility of amino acids by 4.5% (0.781 to 0.816); this was greater than the responses to either phytase (3.6%; 0.781 to 0.809) or xylanase (0.7%; 0.781 to 0.784). Absolute increases in amino acid digestibility with the combination exceeded the sum of the individual increases generated by phytase and xylanase for alanine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, phenylalanine, threonine, tyrosine and valine. These synergistic responses may have resulted from phytase and xylanase having complementary modes of action for enhancing amino acid digestibilities and/or facilitating substrate access. The two remaining experiments were almost identical except wheat used in Experiment 2 had a higher phytate concentration and a lower estimated AME content than wheat used in Experiment 3. Individually, phytase and xylanase were generally more effective in Experiment 2, which probably reflects the higher dietary substrate levels present. Phytase plus xylanase increased (p<0.05) gains (15.4%) and feed efficiency (7.0%) of broiler chicks from 4-24 days post-hatch in Experiment 2; whereas, in Experiment 3, the combination increased (p<0.05) growth to a lesser extent (5.6%) and had no effect on feed efficiency. This difference in performance responses appeared to be 'rotein driven'as the combination increased (p<0.05) nitrogen retention in Experiment 2 but not in Experiment 3; whereas phytase plus xylanase significantly increased AME in both experiments. In Experiments 2 and 3 the combined inclusion levels of phytase and xylanase were lower that the individual additions, which demonstrates the benefits of simultaneously including phytase and xylanase in wheat-based poultry diets.

• Applied Biological Chemistry
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• 제36권6호
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• pp.525-532
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• 1993

쌀의 주요 저장 단백질중의 하나인 알콜용해성 프롤라민의 성질을 분석하고 이들을 동정하기 위하여 유전자 database로부터 얻은 17개의 프롤라민 유전자의 염기서열을 상호비교 분석하였다. 유전자로부터 유추된 단백질 서열의 다중분석결과 프롤라민들은 계통발생적으로 type에서 type IV의 4개의 군으로 크게 분류할 수 있었다. 이러한 분류는 아미노산 서열 중간과 카복실 말단쪽의 짧은 결손에 의해 여러 형태의 아미노산 서열에 의한 것임을 알 수 있었다. 1군에서 4군까지의 군들은 meththionine과 cysteine과 같은 황을 포함하는 아미노산이 각각 1, 4, 10, 30%로 구성된 특징을 보여 주었다. 또한 각 군들은 등전점이 9.2, 8.2, 6.7, 7.4인 각군별로 매우 상이한 등전점을 나타내었다. 아울러 GC3s에 대한 유효 암호수(effective codon number, Nc)와 우선 암호수(preferred codon number)의 분석과 상관 그래프를 통해서 프롤라민 유전자들의 군별 전이 효율의 차이가 현저하여 프롤라민 생산 수준의 군별차이의 가능성을 제시하였다.

• Journal of Microbiology and Biotechnology
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• 제20권1호
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• pp.208-216
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• 2010

Fusarium verticillioides is an important pathogen of maize, being responsible for ear rots, stalk rots, and seedling blight worldwide. During the past decade, F. verticillioides has caused several severe epidemics of maize seedling blight in many areas of China, which lead to significant losses. In order to understand the molecular mechanisms regulating fungal development and pathogenicity in this pathogen, we isolated and characterized the gene fpk1 (GenBank Accession No. EF405959) encoding a homolog of the cAMP-dependent protein kinase catalytic subunit, which included a 1,854-bp DNA sequence from ATG to TAA, with a 1,680-bp coding region, and three introns (lengths: 66 bp, 54 bp, and 54 bp), and the predicated protein precursor had 559 aa. The mutant ${\Delta}fpk1$, which was disrupted of the fpkl gene, showed reduced vegetative growth, fewer and shorter aerial mycelia, strongly impaired conidiation, and reduced spore germination rate. After germinating, the fresh hypha was stubby and lacking of branch. When inoculated in susceptible maize varieties, the infection of the mutant ${\Delta}fpk1$ was delayed and the infection efficiency was reduced compared with that of the wild-type strain. AU this indicated that gene fpk1 participated in hyphal growth, conidiophore production, spore germination, and virulence in F. verticillioides.

• Journal of Microbiology and Biotechnology
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• 제25권1호
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• pp.89-97
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• 2015

Bacillus subtilis HK176 with high fibrinolytic activity was isolated from cheonggukjang, a Korean fermented soyfood. A gene, aprE176, encoding the major fibrinolytic enzyme was cloned from B. subtilis HK176 and overexpressed in E. coli BL21(DE3) using plasmid pET26b(+). The specific activity of purified AprE176 was 216.8 ± 5.4 plasmin unit/mg protein and the optimum pH and temperature were pH 8.0 and 40℃, respectively. Error-prone PCR was performed for aprE176, and the PCR products were introduced into E. coli BL21(DE3) after ligation with pET26b(+). Mutants showing enhanced fibrinolytic activities were screened first using skim-milk plates and then fibrin plates. Among the mutants, M179 showed the highest activity on a fibrin plate and it had one amino acid substitution (A176T). The specific activity of M179 was 2.2-fold higher than that of the wild-type enzyme, but the catalytic efficiency (k_cat/K_m) of M179 was not different from the wild-type enzyme owing to reduced substrate affinity. Interestingly, M179 showed increased thermostability. M179 retained 36% of activity after 5 h at 45℃, whereas AprE176 retained only 11%. Molecular modeling analysis suggested that the 176^th residue of M179, threonine, was located near the cation-binding site compared with the wild type. This probably caused tight binding of M179 with Ca²⁺, whichincreased the thermostability of M179.

• 한국식품과학회지
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• 제8권4호
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• pp.263-272
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• 1976

According to the intercombined review of chemical and biological investigation it has been noted that the metabolizable energy per gram dietary protein of mixed diet of daily intake patterned by Korean population has been found 3.4-3.6 Cal., which entails 10-12% level of the protein calorie percentage of total metabolizable energy, the biological value being fallen within the scope 63-73. The structure of dietary protein has revealed that the lysine and isoleucine were primary limiting amino acids and threonine secondary limiting as a general trend, however, it is assumed that the ultimate nutritional effect of dietary protein might be restricted uniformly among regions by the amount of lysine, since the lysine availability has been yielded as low as 72-82% level. As for the net protein utillization NPUst falls in the range of 52-62 and the NPUop 47-58. In either part the mountainous region has demonstrated lowest value and the urban area highest, these trend being obviously associated with the ratio of animal protein relative to the vegetable origin. The net dietary protein calorie percentage (NDpCal %) has been found within the range of 5-7 that may be capable of meeting the requirement for the maintenance of adult, though for the growth it is insufficient. Present level of total caloric intake would not influence on the fate of protein value of prevailing regional diet in terms of caloric restriction, since the present intake of food energy is higher than the lower limit of caloric intake that would impair the biological performance of dietary protein fed ad libitum basis. Based on the protein efficiency, the adequacy of current level of protein intake was analyzed in terms of utilizable protein, and it has been demonstrated that the 37.8g of utilizable protein in the fishery region and 38.2g in the mountainous region were bellow the FAO recommendation. Accordin to the hematological study it may be interpreted that the anemic symptoms of the mountainous region has some possibility of being related to the inferior status of dietary protein in quality as well as in quantity.

• 한국수산과학회지
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• 제47권6호
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• pp.818-823
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• 2014

This study compared the effects of feeding diets consisting of an experimental extruded pellet with tapioca starch (EEP), commercial extruded pellet (CEP), and raw-fish-based pellet (MP) on the growth, flesh quality, and apparent digestibility coefficient of the olive flounder Paralichthys olivaceus. Two replicated groups of 4,000 fish each (initial mean weight: $81.8{\pm}3.5g$) were fed one of the experimental diets for 5 months. After the feeding trial, the final mean weight, weight gain, specific growth rate, and feed efficiency of fish fed the EEP was significantly higher than those of fish fed the CEP and MP. Moisture content in the whole-body of fish fed MP was significantly higher than those of fish fed other diets. However, the highest crude protein in the whole-body was found in fish groups fed the EEP. Significantly higher contents of 24:1n-9, 20:5n-3, 22:6n-3 and lower 18:1n-7 was observed in fish fed the EEP compared with fish fed the MP. The amino acid contents in the whole-body showed significant differences in the composition depending on the feed, but the distribution of free amino acids showed similar patterns. Among amino acids, glutamic acid showed the highest content in all the experimental groups, and the threonine, cysteine, and lysine contents were significantly higher in the groups fed with EEP and CEP than in the group fed with MP. Digestibility of nutrients of the EEP was significantly higher than that of fish fed the CEP. This suggests that extruded pellets can be used to feed olive flounder without compromising growth and flesh quality in comparison to raw-fish-based moist pellets. Formulation of the EEP could be used as a practical feed for olive flounder.

• Asian-Australasian Journal of Animal Sciences
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• 제28권12호
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• pp.1742-1750
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• 2015

As a novel approach for disease control and prevention, nutritional modulation of the intestinal health has been proved. However, It is still unknown whether branched-chain amino acid (BCAA) is needed to maintain intestinal immune-related function. The objective of this study was to determine whether BCAA supplementation in protein restricted diet affects growth performance, intestinal barrier function and modulates post-weaning gut disorders. One hundred and eight weaned piglets ($7.96{\pm}0.26kg$) were randomly fed one of the three diets including a control diet (21% crude protein [CP], CON), a protein restricted diet (17% CP, PR) and a BCAA diet (BCAA supplementation in the PR diet) for 14 d. The growth performance, plasma amino acid concentrations, small intestinal morphology and intestinal immunoglobulins were tested. First, average daily gain (ADG) (p<0.05) and average daily feed intake (ADFI) (p<0.05) of weaned pigs in PR group were lower, while gain:feed ratio was lower than the CON group (p<0.05). Compared with PR group, BCAA group improved ADG (p<0.05), ADFI (p<0.05) and feed:gain ratio (p<0.05) of piglets. The growth performance data between CON and BCAA groups was not different (p>0.05). The PR and BCAA treatments had a higher (p<0.05) plasma concentration of methionine and threonine than the CON treatment. The level of some essential and functional amino acids (such as arginine, phenylalanine, histidine, glutamine etc.) in plasma of the PR group was lower (p<0.05) than that of the CON group. Compared with CON group, BCAA supplementation significantly increased BCAA concentrations (p<0.01) and decreased urea concentration (p<0.01) in pig plasma indicating that the efficiency of dietary nitrogen utilization was increased. Compared with CON group, the small intestine of piglets fed PR diet showed villous atrophy, increasing of intra-epithelial lymphocytes (IELs) number (p<0.05) and declining of the immunoglobulin concentration, including jejunal immunoglobulin A (IgA) (p = 0.04), secreted IgA (sIgA) (p = 0.03) and immunoglobulin M (p = 0.08), and ileal IgA (p = 0.01) and immunoglobulin G (p = 0.08). The BCAA supplementation increased villous height in the duodenum (p<0.01), reversed the trend of an increasing IELs number. Notably, BCAA supplementation increased levels of jejunal and ileal immunoglobulin mentioned above. In conclusion, BCAA supplementation to protein restricted diet improved intestinal immune defense function by protecting villous morphology and by increasing levels of intestinal immunoglobulins in weaned piglets. Our finding has the important implication that BCAA may be used to reduce the negative effects of a protein restricted diet on growth performance and intestinal immunity in weaned piglets.

• 한국수산과학회지
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• 제47권3호
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• pp.227-233
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• 2014

We designed a 16-week feeding experiment to test the effects of dietary supplementation with distillers' dried grain (DDG) on the growth, feed utilization, and body composition of juvenile muddy loach Misgurnus anguillicaudatus. Seven isonitrogenous and isocaloric diets were formulated to contain 0% DDG (Control); 10%, 20%, and 30 % DDG from rice (diets RM10, RM20 and RM30); and 10%, 20%, and 30% DDG from rice and wheat flour (diets RWM10, RWM20 and RWM30), respectively. Three replicate groups of juvenile muddy loach averaging $1.5{\pm}0.10$ g were fed one of the diets to satiation twice daily. Survival of juvenile muddy loach fed the RWM20 and RWM30 diets was higher than that of the control group (P<0.05), while weight gain tended to decrease when fish were fed diets containing DDG. Weight gain of fish fed the RWM10 diet was greater than that of fish fed other diets, but the RM30 diet resulted in less weight gain than did the control (P<0.05). The feed and protein efficiency ratios of fish fed the RM10, RM20, RM30, RWM10, RWM20 and RWM30 diets were all similar to the control (P>0.05). Neither daily feed intake nor proximate composition of the whole body was affected by dietary DDG (P>0.05). The compositions of isoleucine, leucine, lysine, threonine, and valine were all elevated in fish fed the RM30, RWM10, RWM20 and RWM30 diets relative to those of other groups (P<0.05). In contrast, methionine + cystine and phenylalanine + tyrosine were all lower in fish fed the RM30, RWM10, RWM20 and RWM30 diets, as compared to those of other groups (P<0.05). Our results suggest that DDG is suitable as a partial replacement for soybean meal and wheat flour, and could be used at a rate of up to 20% for rice, or 30% for rice and wheat flour, for optimum growth performance of juvenile muddy loach.