• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제11권2호
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• pp.133-148
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• 2005

단백질 구조에 대한 유사성과 특이성에 대한 이해는 단백질의 기능을 파악하는데 있어 중요한 역할을 하고 있기 때문에, 많은 단백질 구조를 비교하는 시스템이 개발되고 있다. 그러나 이러한 시스템들은 단백질 구조 비교를 위한 자신의 알고리즘에 맞게 PDB에서 제공하는 데이타를 가공해야 한다 더욱이 PDB 데이타베이스에 저장된 데이타가 증가함에 따라 대용량의 단백질 구조 데이타베이스를 대상으로 주어진 단백질과 유사한 부분구조를 찾는 시스템은 보다 많은 계산량이 필요하여진다. 본 논문에서는 XML 데이타베이스인 eXist를 이용하여 PSAML 문서를 제공하는 PSAML 데이타베이스에 기반을 둔 WS4E(A Web-Based Searching Substructures of Secondary Structure Elements) 단백질 구조 비교 시스템을 소개한다. PSAML(Protein Structure Abstraction Markup Language)은 XML기반의 단백질 구조 표현 기법으로서 단백질의 2차구조 구성요소와 그들 사이의 관계를 이용하여 단백질 구조를 정형화된 방법으로 기술한다. 구축된 PSAML 데이타베이스를 이용하여, WS4E는 PSAML로 표현된 단백질 구조에서 유사한 부분 구조를 찾는 웹서비스를 제공한다. 또한, PSAML 데이타베이스에서 비교 대상이 되는 단백질의 숫자를 감소시키기 위하여, 단백질 2차구조가 가지는 공간상의 정보를 이용하여 하나의 단백질 구조를 표현하는 기법인 topology string을 이용하였다.

• International Journal of Industrial Entomology and Biomaterials
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• 제4권2호
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• pp.101-107
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• 2002

We describe here the cDNA sequence and mRNA expression of a novel family of the antioxidant protein, peroxiredoxin, from the firefly, Pyracoetia ruin. The 555 bp cDNA sequence codes for a 185 amino acid protein with a calculated molecular mass of approximately 21 kDa. The deduced protein of P. rufa peroxiredoxin gene contains two conserved cysteine residues. Alignment of the deduced protein of P. rufa peroxiredoxin gene showed 71.1% protein sequenceidentity to known insect Drosophila melanogaster peroxiredoxin. Northern blot analysis revealed that the P. rufa peroxiredoxin is specifically expressed in the fat body of P. rufa larvae.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권2호
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• pp.145-149
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• 2004

The expression of a fusion protein comprised of the B. thuringiensis crystal protein, Cry1Ac, and enhanced green fluorescent protein (EGFP) in Escherichia coli XLl-blue was examined. Three recombinant plasmids were transformed into E. coli XL1-blue and named as ProAc/Ec, MuEGFP/Ec and ProMu-EGFP/Ec, respectively. All transformants were observed by light and fluorescence microscopy at mid-log phase. The expression in E. coli transformants, ProMu-EGFP/Ec and MuEGFP/Ec, exhibited bright enough fluorescence to be observed. Furthermore, ProMu-EGFP/Ec produced fluorescent inclusions, which may have been recombinant crystals between EGFP and Cry1Ac while MuEGFP/Ec expressed soluble EGFP in cell. In SDS-PAGE, ProAc/Ec had 130 kDa crystal protein band and MuEGFP/Ec had thick 27 kDa EGFP band. However, ProMu-EGFP/Ec had about 150 kDa fusion protein band. Accordingly, these results indicated that a fusion protein between the B. thuringiensis crystal protein and a foreign protein under the lacZ promoter was successfully expressed as granular structure in E. coli. It is suggested that the E. coli expression system by N-terminal fusion of B. thuringiensis crystal protein may be useful as excellent means for fusion expression and characterization of B. thuringiensis fusion crystal protein.

• Asian-Australasian Journal of Animal Sciences
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• 제29권2호
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• pp.241-249
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• 2016

The supplementation of livestock feed with animal protein is a present cause for public concern, and plant protein shortages have become increasingly prominent in China. This conflict may be resolved by fully utilizing currently available sources of plant protein. We estimated the rumen degradability and the small intestinal digestibility of the amino acids (AA) in rapeseed meal (RSM), soybean meal (SBM), sunflower seed meal (SFM) and sesame meal (SSM) using the mobile nylon bag method to determine the absorbable AA content of these protein supplements as a guide towards dietary formulations for the dairy industry. Overall, this study aimed to utilize protein supplements effectively to guide dietary formulations to increase milk yield and save plant protein resources. To this end, we studied four cows with a permanent rumen fistula and duodenal T-shape fistula in a $4{\times}4$ Latin square experimental design. The results showed that the total small intestine absorbable amino acids and small intestine absorbable essential amino acids were higher in the SBM (26.34% and 13.11% dry matter [DM], respectively) than in the SFM (13.97% and 6.89% DM, respectively). The small intestine absorbable Lys contents of the SFM, SSM, RSM and SBM were 0.86%, 0.88%, 1.43%, and 2.12% (DM basis), respectively, and the absorbable Met contents of these meals were 0.28%, 1.03%, 0.52%, and 0.47% (DM basis), respectively. Among the examined food sources, the milk protein score of the SBM (0.181) was highest followed by those of the RSM (0.136), SSM (0.108) and SFM (0.106). The absorbable amino acid contents of the protein supplements accurately reflected protein availability, which is an important indicator of the balance of feed formulation. Therefore, a database detailing the absorbable AA should be established.

• Asian-Australasian Journal of Animal Sciences
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• 제21권11호
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• pp.1629-1634
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• 2008

A trial was conducted to determine the effect of low crude protein (CP) diets with constant metabolizable energy to crude protein (ME:CP) ratio on growth, body composition and nutrient utilization of broiler chicks from 1 to 26 days of age. Four dietary treatments having four levels of CP and ME as 23, 22, 21 and 20% and 3,036, 2,904, 2,772 and 2,640 kcal/kg, respectively, were formulated and a ME:CP ratio of 132 was maintained in all the diets. Digestible lysine was maintained at 1.10 of the diet. A total of 1,760 day-old Hubbard broiler chicks were randomly divided into 16 experimental units and each diet was offered to four experimental units at random. Feed intake was increased (p<0.05) while weight gain and feed conversion ratio were adversely affected (p<0.05) when the diets with low CP and ME were fed to broilers. Total protein intake and total ME intake were linearly decreased (p<0.05) and protein efficiency ratio and energy efficiency ratio were lower (p<0.05) than in the chicks fed dietary regimen with 22% CP and 2,904 kcal/kg ME. The whole body analysis of the birds revealed that chicks fed the lowest dietary regimens retained less (p<0.05) nitrogen and more ether extract than chicks fed the control diet, however, body dry matter, total body ash and fat free body protein were not affected. Similarly, protein and energy utilization were also unaffected by the dietary treatments. In summary, chicks fed low CP diets with constant ME:CP ratio grew slower, used feed less efficiently and retained less protein and more body fat than chicks fed the control diet.

• Nutritional Sciences
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• 제5권2호
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• pp.53-59
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• 2002

This study was conducted to examine the effects of dietary sources of fatty acids and protein on serum protein profiles, hepatic functional enzyme activities, mammary tumor incidence and tumor weight in 7, 12-dimethylbenz($\alpha$)anthracene (DMBA)-treated rats. The sources of dietary fatty acids were 18n6 (rich in linoleic acid), 18n3 (rich in linolenic acid) and 22n3 (rich in DHA) : sources of dietary protein were casein (C) and soy protein isolate (S). mammary tumors (MTs) were chemically induced by DMBA (9 mg/100 g body weight) which was gastrically intubated at 7 weeks of age. Each experimental diet was given for the following 25 weeks. Casein-fed rats (group C) exhibited significantly higher levels of weight gain and FER (food efficiency ratio) than did group S. Group C showed higher levels of serum protein and globulin, and higher albumin/globulin (A/G) ratios than group S. Liver functional enzyme activities (GOT, GPT, ALP, LDH, $\gamma$-GT) and LDH/GOT ratios were not influenced by dietary protein. GPT activity was lower in the group given 18n3, and ALP activity was lower in the group given 18n6. The incidence and total number of MTs appeared to be lower in the group given 22n3 than in the group given 18n3 or 18n6, even though the average weight of MTs was highest in the group given 22n3, The average weight of MTs was higher in the C group than in the S group. MT incidence had a positive correlation with LDH activity and LDH/GOT ratio. The average weight of MTs had a negative correlation with serum albumin levels and A/G ratios, and a positive correlation with ALP activity. This research suggests that the measurement of serum protein profiles and liver functional enzyme activities may be utilized to monitor the development of mammary tumors.

• 한국가금학회지
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• 제44권2호
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• pp.67-73
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• 2017

The purpose of our study was to determine the effects of varying levels of energy, protein, and amino acids on the performances of laying hens. A total of 240 Hy-Line Brown laying hens at 36 weeks of age were used in this 4-week feeding trial. The hens were randomly allocated to five treatment diets, with eight replications of six hens in each replicate cage. The treatment diets were as follows: A- basal diet + 18% crude protein, metabolizable energy 2,800 kcal, total (methionine + cysteine) 0.65%; B- basal diet + 17% crude protein, metabolizable energy 2,700 kcal, total (methionine + cysteine) 0.59%; C- basal diet + 16.5% crude protein, metabolizable energy 2,700 kcal, total (methionine + cysteine) 0.59%; D- basal diet + 16.5% crude protein, metabolizable energy 2,700 kcal, total (methionine + cysteine) 0.54%; and E- basal diet + 16% crude protein, metabolizable energy 2,680 kcal, total (methionine + cysteine) 0.54%. The study results revealed that the hen-day egg production of hens that were fed with low-energy diets (B, C, and D) was comparable with that of hens fed with high-energy diet A, whereas average daily feed intake in hens fed treatment diet D and E was significantly higher (P<0.05) than that in hens fed treatment diet A. Overall, the eggshell thickness was unaffected by any of the treatment diets. Egg weight was comparable among the treatment diets, except for treatment diet E. Haugh unit improved with decreasing levels of dietary energy, protein, and methionine + cysteine in the diet. We can summarize that laying hens fed with low dietary energy and low crude protein treatment diets B, C, and D had satisfactory performance compared with those fed with high-energy treatment diet A. This indicates that there is the potential to reduce feed costs by formulating diets with lower energy and low protein levels.

• 생명과학회지
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• 제17권2호통권82호
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• pp.179-184
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• 2007

단백질 티로신 kinase인 PTK6는 대부분의 유방암에서 과발현되며, 암세포의 증식만을 촉진하는데 역할을 한다. 이 연구에서 PTK6의 활성도메인을 초파리의 peptidoglycan recognition protein (PGRP) -LB 단백질을 퓨전파트너로 사용하여 바큘로바이러스 시스템을에서 과발현하는데 성공하였다. 우리는 PGRP-LB가 바큘로바이러스 시스템에서 잠재적으로 퓨전 단백질로 사용될 수 있는 가능성을 처음으로 발견하였다. 정제된 PTK6단백질은 기존의 박테리아에서 발현된 단백질보다 1.5배 높은 활성을 지녔다. 이 단백질은 PTK6의 분자기전 및 그것의 저해제 개발에 필수적인 결정 구조를 규명하는데 사용될 것이다.

• 생명과학회지
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• 제21권1호
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• pp.31-35
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• 2011

Dual-specificity protein phosphatase (DUSP)들은 인산화된 티로신 잔기와 인산화된 세린 또는 트레오닌 잔기를 탈인산화시키는 단백질 탈인산화효소 군을 이루고 있으며, 대부분의 DUSP들은 세포의 생존이나 분화에 관여하고 있다. 본 연구에서는 잘 알려지지 않은 인간 유래의 dual-specificity protein phosphatase인 DUSP28을 인간신장 cDNA에서 분리하였다. 대장균에서 생산된 재조합단백질은 6,8-difluoro-4-methylumbelliferyl phosphate (DiFMUP)에 대하여 좋은 활성을 보였다. 다양한 저해제와 2가 금속이온들이 DUSP28의 활성에 미치는 영향을 조사하였다. 다른 DUSP들에서와는 다르게, $Zn^{2+}$은 DUSP28의 탈인산화활성을 강하게 억제하였다. 이러한 결과로부터 DUSP28이 Zn과 연관된 신호전달경로에 관여할 것으로 추정된다. 더욱이, DUSP28은 인산화된 티로신잔기를 더욱 선호하는 경향이 있는 것으로 나타났고, 이는 세포 내에서도 비슷한 작용을 할 것으로 예상된다.

• Genomics & Informatics
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• 제18권3호
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• pp.28.1-28.9
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• 2020

Streptomyces coelicolor is a gram-positive soil bacterium which is well known for the production of several antibiotics used in various biotechnological applications. But numerous proteins from its genome are considered hypothetical proteins. Therefore, the present study aimed to reveal the functions of a hypothetical protein from the genome of S. coelicolor. Several bioinformatics tools were employed to predict the structure and function of this protein. Sequence similarity was searched through the available bioinformatics databases to find out the homologous protein. The secondary and tertiary structure were predicted and further validated with quality assessment tools. Furthermore, the active site and the interacting proteins were also explored with the utilization of CASTp and STRING server. The hypothetical protein showed the important biological activity having with two functional domain including POD-like_MBL-fold and rhodanese homology domain. The functional annotation exposed that the selected hypothetical protein could show the hydrolase activity. Furthermore, protein-protein interactions of selected hypothetical protein revealed several functional partners those have the significant role for the bacterial survival. At last, the current study depicts that the annotated hypothetical protein is linked with hydrolase activity which might be of great interest to the further research in bacterial genetics.