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Journal of Animal Science and Biotechnology 2020年第1期11卷 121-131页

作者： Hongkui Wei Xichen Zhao Mao Xia Chengquan Tan Jun Gao John KHtoo Chuanhui Xu Jian Peng Department of Animal Nutrition and Feed Science College of Animal Science and TechnologyHuazhong Agricultural UniversityWuhanPeople’s Republic of China Department of Animal Nutrition and Feed Science College of Animal ScienceSouth China Agricultural UniversityGuangzhouPeople’s Republic of China Evonik Degussa(China)Co. LtdBeijingPeople’s Republic of China Evonik Nutrition&Care GmbH Hanau-WolfgangEssenGermany The Cooperative Innovation Center for Sustainable Pig Production WuhanPeople’s Republic of China.

Background:Over the last decade,the nutritional requirements of lactating modern genotype sows have increased.The current nutritional recommendations might be unable to meet the needs of increased litter size and milk production,and thus the nutritional requirements need to be re-evaluated.The current study was conducted to investigate the effects of dietary methionine to lysine(Met:lys)ratios on the performance of and methionine metabolism in lactating sows.Results:During the 1st week of lactation,piglets reared on sows in the 0.37 to 0.57 Met:lys ratio groups grew faster than those reared on sows in the control group(0.27)(Plys ratios in the lactation diet.Conclusions:The current study indicated that increasing the dietary Met:lys ratio(0.37~0.57)in the lactation diet had no significant effect on the overall performance of sows or the colostrum and milk composition,but it increased piglet mean BW and piglet ADG during the first week of lactation.Increasing dietary methionine levels had no significant effect on antioxidant function in lactation sows,even though it increased levels of GSH and GSH-Px in the plasma of sows during lactation.However,the content of homocysteine in the plasma and milk increased during lactation due to a high level of dietary methion

关键词： Lactation Methionine Met to lys ratios Oxidative stress Piglet growth performance Sow performance

CRYSTAL STRUCTURE DETERMINATION OF MUNG BEAN TRYPSIN INHIBITOR lys FRAGMENT-BOVINE TRYPSIN COMPLEX——MOLECULAR REPLACEMENT,ELECTRON DENSITY MAP AT 3.0 ■ RESOLUTION

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Science China Chemistry 1987年第12期30卷 1280-1288页

作者：曾杰陈忠国李根培卫新成卢光莹唐有祺林光大张荣光宣建成戚正武曹天钦 Institute of Physical Chemistry and Department of Biology Academia Sinica Shanghai Institute of Biochemistry Peking University

The orientation and position of the trypsin molecule in the complex crystal cell mung bean trypsin inhibitor lys fragment （MBILF）-bovine trypsin （BTRY） have been successfully determined by molecular replacement method with the model of the refined bovine trypsin molecule.Starting from the BTRY coordinates which were oriented and located in the correct azimuth and position in the complex cell according to the result from rotation function and translation function, sim-weighted Fourier map with coefficients 2|F|-|F| at 3.0 resolution was calculated.Besides the electron density which is obviously attributed to itself, in the vicinity of the active site of BTRY the dense contour levels corresponding to the MBILF and its boundary could be clearly seen in this map. The size of MBILF was approximately estimated at 15×15×25.

关键词： MOLECULAR REPLACEMENT,ELECTRON DENSITY MAP AT 3.0 RESOLUTION CRYSTAL STRUCTURE DETERMINATION OF MUNG BEAN TRYPSIN INHIBITOR lys FRAGMENT-BOVINE TRYPSIN COMPLEX lys maps MBI AT

THE CRYSTALLOGRAPHIC STUDY OF THE COM PLEX OF THE lys ACTIVE FRAGMENT OF THE MUNG BEAN TRYPSIN INHIBITOR WITH BOVINE TRYPSIN

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Science in China,Ser.B 1985年第11期28卷 1163-1166页

作者：张荣光林光大严友为唐伟中谭复隆戚正武曹天钦 Shanghai Institute of Biochemistry Academia Sinica

The lys fragment of mung bean trypsin inhibitor can combine with bovine trypsin to form a complex at an equal molar ratio. The single cxystals of the complex were obtained by using the micro-still-setting method and the X-ray diffraction extended to 1.8 resolution. Its space group is P212121 wlth cell dimensions α=62.9（1）, b=63.4（1） and c=69.7（2）. There is one complex molecule in a crystallographic asymmetric unit.

关键词： THE CRYSTALLOGRAPHIC STUDY OF THE COM PLEX OF THE lys ACTIVE FRAGMENT OF THE MUNG BEAN TRYPSIN INHIBITOR WITH BOVINE TRYPSIN lys

Semantics-Based Compliance An a lys is o f N e two rk S e cu rity Policy Hie ra rch ie s

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China Communications 2012年第7期9卷 22-35页

作者： Yao Shan Xia Chunhe Hu Junshun Jiao Jian Li Xiaojian Beijing Key Laboratory of Network Technology Beihang University Beijing 100191 P. R. China Beijing Information Technology University Beijing 100192 P. R. China College of Computer Science and Information Technology Guangxi Normal University Guilin 541004 P. R. China

Network security policy and the automated refinement of its hierarchies aims to simplify the administration of security services in complex network environments. The semantic gap between the policy hierarchies reflects the validity of the policy hierarchies yielded by the automated policy refinement process. However, little attention has been paid to the evaluation of the compliance between the derived lower level policy and the higher level policy. We present an ontology based on Ontology Web Language (OWL) to describe the semantics of security policy and their implementation. We also propose a method of estimating the semantic similarity between a given higher level security policy and the lower level ones to evaluate the compliance for the policy refinement approach. The method is verified in the case study. The experimental results demonstrate that the proposed method evaluates the semantic similarity between policy and implementation accurately, and that the algorithm of concept similarity analysis reflects the subjective similarity judgment of policy and implementation more accurate than the other algorithms.

关键词：语义本体Web语言 lys 立方网络安全策略层次结构安全服务网络环境

Intriguing Origins of Protein lysine Methylation:Influencing Cell Function Through Dynamic Methylation

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Genomics, Proteomics & Bioinformatics 2019年第6期17卷 551-557页

作者： Natalie Mezey William C.S.Cho Kyle K.Biggar Institute of Biochemistry and Department of Biology Carleton UniversityOttawaON K1S 5B6Canada Department of Clinical Oncology Queen Elizabeth HospitalKowloonHong Kong Special Administrative RegionChina

Introduction“There is a kink(shoulder)on[the]lys peak...”These words scribed in Richard P.Ambler’s laboratory notebook marked the discovery of protein methylation and a segue into a new field of scientific research[1].Initially,through ion-exchange chromatography and two-dimensional paper chromatography of the hydrolysate of Salmonella typhimurium flagellin,this“kink”was interpreted as a“new amino acid”,the e-Nmethyl-lysine(NML).This discovery,bolstered by a subsequent examination of purified NML,was the first glimpse of protein methylation in living cells[1].

关键词： lys Intriguing Origins of Protein lysine Methylation:Influencing Cell Function Through Dynamic Methylation

基于MS2噬菌体lys基因的质粒型条件自溶菌的构建与应用

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微生物学通报 2022年第11期49卷 4598-4607页

作者：吕敏佳刘捷婧周于婷陈萍欧阳永长广州医科大学生物化学与分子生物学教研室广东广州511436 广州医科大学附属第二医院转化医学中心广东广州510260

【背景】传统外源蛋白的原核表达通常需要以超声破碎或者酶解的方式破碎菌体,过程比较烦琐。【目的】构建基于MS2噬菌体lys基因的质粒型条件自溶菌,以简化外源蛋白的获取流程。【方法】从MS2噬菌体中克隆lys基因,构建重组表达质粒,并在... 详细信息

【背景】传统外源蛋白的原核表达通常需要以超声破碎或者酶解的方式破碎菌体,过程比较烦琐。【目的】构建基于MS2噬菌体lys基因的质粒型条件自溶菌,以简化外源蛋白的获取流程。【方法】从MS2噬菌体中克隆lys基因,构建重组表达质粒,并在大肠杆菌BL21(DE3)中异源表达,以此构建质粒型条件自溶菌,通过生长曲线和菌落形成单位反映自溶菌裂解效率,利用SDS-PAGE检测外源蛋白释放情况。【结果】构建了pBAD-lysBL21(DE3)、pBAD-Opti-lys BL21(DE3)及pCDF-BAD-Opti-lys BL21(DE3)这3种质粒型条件自溶菌。以上自溶菌在阿拉伯糖诱导后其宿主裂解效率均为99.99%以上,CFU结果显示含pCDF-BAD-Opti-lys质粒的宿主裂解效果更优,在此自溶菌BL21(DE3)中表达含His标签的重组绿色荧光蛋白(enhancedgreenfluorescent protein,eGFP),经阿拉伯糖诱导后菌体中约63.00%以上的eGFP释放至胞外,利用Ni-NTA可以直接从培养基中纯化得到约30 kDa的单一目的蛋白。【结论】基于MS2噬菌体lys基因成功构建了阿拉伯糖诱导的质粒型条件自溶菌,此自溶菌能够以自我裂解的方式释放大部分胞内外源蛋白,简化传统外源蛋白获取流程。

关键词： MS2噬菌体 lys 自溶菌蛋白纯化

PURIFICATION AND PRIMARY STRUCTURES OF DUCK FIBRINOPEPTIDES A AND B

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Science in China,Ser.B 1985年第1期28卷 31-35页

作者：袁敏朱平张耀时 Cardiovasoular Laboratory shanghai Chest Hospital Shanghai Institute of Biochemistry Academia Sinica

Duck fibrinopeptides A and B were purified by Dowex 50 W×2 ion exchange resin and DEAE-Sepharose CL-6B. The complete primary structures of duck fibrinopeptides A and B were determined by nianual Edman Sequence determination. The primary structure of duck fibrinopeptide A is pyr. Asp. Gly. lys. Ser. Set. Phe.Gln. lys. Glu. Gly, G]y. Gly, Val. Arg., and that of duck fibrinopeptide B is Pyr. Ala, Ser, Thr, Asp, Tyr. Asp. Asp. Glu. Asp. Glu. Ser. Thr. Val. Pro. Glu. Ala. Arg.

关键词： lys Gly PURIFICATION AND PRIMARY STRUCTURES OF DUCK FIBRINOPEPTIDES A AND B PTH

MULTIPLE SYNTHESIS OF SMALLPEPTIDE ANALOGS

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Chinese Chemical Letters 1993年第5期4卷 399-402页

作者： De Xin WANG and Gui Shen LU Institute of Materia, Chinese Academy of Medical Sciences, Beijing 100050

Two peptide analogs H-Tyr-Thr-Pro-Arg-lys-OH (1) and H-Tyr-Thr-Pro-Phe-lys-OH (2) were prepared successfully by the technique of simultaneous multiple peptides synthesis(SMPS) on a single resin support. The profiles of HPLC and amino acid analysis indicated that the purity of 1 and 2 was satisfactory. The average yield(74.9％) of each peptide was reasonable. This new technique of SMPS offered significant savings not only in time but in many expensive reagents as well.

关键词： Pro lys OH SMPS MULTIPLE SYNTHESIS OF SMALLPEPTIDE ANALOGS

高效弱阳离子交换色谱法对脲还原变性溶菌酶的折叠研究

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化学学报 2005年第7期63卷 597-602,F007页

作者：刘红妮王彦龚波林耿信笃西北大学现代分离科学研究所分离科学陕西省重点实验室西安710069

用高效弱阳离子交换色谱(HPWCX)对脲还原变性溶菌酶(lys)进行了复性研究.在流动相中脲浓度固定为4.0mol?L-1和选用对天然态蛋白有稳定作用的硫酸铵为盐或置换剂时,在蛋白浓度为15.0～50.0mg?mL-1时,HPWCX法比稀释法活性回收率高.为了提... 详细信息

用高效弱阳离子交换色谱(HPWCX)对脲还原变性溶菌酶(lys)进行了复性研究.在流动相中脲浓度固定为4.0mol?L-1和选用对天然态蛋白有稳定作用的硫酸铵为盐或置换剂时,在蛋白浓度为15.0～50.0mg?mL-1时,HPWCX法比稀释法活性回收率高.为了提高lys的质量及活性回收率对所用色谱条件进行了优化研究,当蛋白起始浓度为20.0mg?mL-1时,lys的质量回收率和活性收率分别为97.8%和95.4%.表明此种方法简便且有可能对其他还原变性蛋白的复性具有通用性.

关键词：离子交换色谱法溶菌酶还原高效折叠脲回收率稳定作用蛋白浓度优化研究色谱条件起始浓度变性蛋白 lys 置换剂硫酸铵流动相活性稀释法通用性复性质量