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牛支原体能量耦合因子转运蛋白S组件Mb BioY摄取外源生物素的功能分析
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作者 陈启伟 权衡 +5 位作者 陈胜利 刘东慧 于永峰 李彩玉 宫晓炜 储岳峰 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第1期282-289,共8页
牛支原体(M.bovis)感染与生存依赖于外界微环境提供的各类营养代谢因子。开展M.bovis外源生物素摄取的机制研究,将对M.bovis防控具有极其重要的意义。通过对M.bovis PG45 Mb BioY(MBOVPG45_0349)基因进行系统发育分析、分子对接分析,筛... 牛支原体(M.bovis)感染与生存依赖于外界微环境提供的各类营养代谢因子。开展M.bovis外源生物素摄取的机制研究,将对M.bovis防控具有极其重要的意义。通过对M.bovis PG45 Mb BioY(MBOVPG45_0349)基因进行系统发育分析、分子对接分析,筛选M.bovis PG45 Mb BioY突变株,比较PG45和PG45ΔMb BioY的生物素敏感性,异源构建Mb BioY功能性克隆验证其功能。结果表明,PG45染色体上存在一种崭新的生物素膜转运蛋白,全长996 bp,GC含量30.95%,蛋白长度为332个氨基酸,是由7个跨膜结构域组成的能量偶合因子(ECF)转运蛋白S成分Mb BioY。进一步验证后发现,当M.bovis缺失Mb BioY会影响其生长,表现出生物素代谢营养缺陷的表型。通过异源敲入生物素代谢营养缺陷大肠杆菌MG1655,表明Mb BioY单独存在时,就能够恢复生物素代谢营养缺陷大肠杆菌缺失株的生理功能。初步证明,Mb BioY编码的是能量偶合因子(ECF)转运蛋白的S成分具有摄取外源生物素的能力,该研究结果将补充细菌生物素代谢调控的多样性和复杂性,为M.bovis的有效防控提供独特视角。 展开更多
关键词 牛支原体 能量耦合因子转运体 生物素 转运
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生物素对荷斯坦奶牛泌乳性能、养分消化和瘤胃发酵的影响
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作者 郭天雄 周则闻 +4 位作者 安静 王聪 刘强 郭刚 张亚伟 《动物营养学报》 CAS CSCD 北大核心 2024年第1期352-359,共8页
本试验旨在研究生物素对荷斯坦奶牛泌乳性能、养分消化和瘤胃发酵的影响。选取产奶量、胎次和泌乳天数相近的荷斯坦奶牛48头,随机分为4组,分别在基础饲粮中添加0(对照组)、10、20和30 mg/d的生物素,每组12头牛。预试期20 d,正试期60 d... 本试验旨在研究生物素对荷斯坦奶牛泌乳性能、养分消化和瘤胃发酵的影响。选取产奶量、胎次和泌乳天数相近的荷斯坦奶牛48头,随机分为4组,分别在基础饲粮中添加0(对照组)、10、20和30 mg/d的生物素,每组12头牛。预试期20 d,正试期60 d。正试期间,记录每头牛每天的采食量和产奶量,采集饲粮、奶、粪便、瘤胃液和血液样品,测定乳成分含量、养分表观消化率、瘤胃发酵参数和血液指标。结果表明:随着生物素添加水平的提高,奶牛干物质采食量无显著变化(P>0.05);产奶量、乳脂肪和乳蛋白质产量、乳脂肪含量以及饲料效率呈线性提高(P<0.05);各养分表观消化率呈线性提高(P<0.05);瘤胃pH和乙酸/丙酸值呈线性降低(P<0.05);瘤胃总挥发性脂肪酸、乙酸和丙酸含量呈线性提高(P<0.05);瘤胃嗜淀粉瘤胃杆菌、溶纤维丁酸弧菌、白色瘤胃球菌、黄色瘤胃球菌、总细菌和总真菌数量呈线性提高(P<0.05);血清葡萄糖、甘油三酯和胰岛素含量无显著变化(P>0.05),血清非酯化脂肪酸和β-羟丁酸含量呈线性降低(P<0.05),血清生物素含量呈线性提高(P<0.05)。由此可见,补充生物素改善了奶牛泌乳性能、养分消化和瘤胃发酵,推荐生物素添加水平为20 mg/d。 展开更多
关键词 生物素 奶牛 产奶性能 养分消化 瘤胃发酵
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生物素对产蛋期种鹅血清生化指标、肠道黏膜上皮形态及肠道菌群结构的影响
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作者 孙小怡 张名爱 +4 位作者 王宝维 凡文磊 孔敏 岳斌 王秉翰 《动物营养学报》 CAS CSCD 北大核心 2024年第4期2395-2405,共11页
本试验旨在研究生物素对产蛋期种鹅血清生化指标、肠道黏膜上皮形态及肠道菌群结构的影响。试验选用150只体型相近的34周龄五龙鹅(豁眼鹅)种鹅,随机分为6组,每组5个重复,每个重复5只鹅(1公4母)。各组饲粮中生物素添加水平分别为0(对照)... 本试验旨在研究生物素对产蛋期种鹅血清生化指标、肠道黏膜上皮形态及肠道菌群结构的影响。试验选用150只体型相近的34周龄五龙鹅(豁眼鹅)种鹅,随机分为6组,每组5个重复,每个重复5只鹅(1公4母)。各组饲粮中生物素添加水平分别为0(对照)、0.1、0.2、0.3、0.4和0.5 mg/kg。预试期1周,正试期17周。结果表明:1)饲粮生物素添加水平对血清总胆固醇、低密度脂蛋白胆固醇、甘油三酯含量没有显著影响(P>0.05)。0.2、0.3、0.4 mg/kg生物素组的血清总蛋白含量显著高于对照组(P<0.05),0.1、0.2、0.3、0.5 mg/kg生物素组的血清白蛋白含量显著高于对照组(P<0.05),0.2、0.3、0.4、0.5 mg/kg生物素组的血清高密度脂蛋白胆固醇含量显著高于对照组(P<0.05)。2)0.2、0.3、0.4、0.5 mg/kg生物素组的十二指肠绒毛高度显著高于对照组(P<0.05),且0.2 mg/kg生物素组的十二指肠绒毛高度显著高于其他各组(P<0.05)。0.3 mg/kg生物素组的十二指肠绒毛高度/隐窝深度显著高于除0.2 mg/kg生物素组外的其他各组(P<0.05)。饲粮生物素添加水平对十二指肠隐窝深度没有显著影响(P>0.05)。3)与对照组相比,0.2 mg/kg生物素组的盲肠福西亚马赛菌属和侏儒杆菌属的相对丰度显著升高(P<0.05),盲肠罗姆布茨菌属、苏黎世杆菌属、黄酮菌属的相对丰度显著降低(P<0.05)。由此可见,饲粮中添加适宜水平生物素可以促进产蛋期种鹅肠道黏膜上皮形态发育,调节肠道菌群结构。在本试验条件下,产蛋期种鹅饲粮生物素适宜添加水平为0.26~0.34 mg/kg。 展开更多
关键词 产蛋期种鹅 生物素 血清生化指标 黏膜上皮形态 菌群结构
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CpOGA^(D298N)与核心链霉亲和素Stv13融合表达用于检测蛋白质O⁃GlcNAc修饰
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作者 黎先感 杨明 +4 位作者 鲁莹 李玲 马骞 李静 张连文 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2024年第4期513-519,共7页
氧连接的β-N-乙酰葡萄糖胺修饰(O-GlcNAc修饰)是一种发生在蛋白质丝氨酸、苏氨酸羟基上的一种动态、可逆的翻译后修饰。O-GlcNAc修饰在细胞的许多关键过程中发挥重要作用,也是研究阿尔茨海默病和糖尿病等的重要途径,但是常用于O-GlcNA... 氧连接的β-N-乙酰葡萄糖胺修饰(O-GlcNAc修饰)是一种发生在蛋白质丝氨酸、苏氨酸羟基上的一种动态、可逆的翻译后修饰。O-GlcNAc修饰在细胞的许多关键过程中发挥重要作用,也是研究阿尔茨海默病和糖尿病等的重要途径,但是常用于O-GlcNAc蛋白检测的抗体特异性或者检测分子量范围仍存在问题且耗时(~36 h)过长,对后续研究造成困扰。在本研究中,我们设计构建了产气荚膜梭菌OGA(O-GlcNAcase)突变体(CpOGA^(D298N))与核心链霉亲和素Stv13融合表达质粒pET28a-CpOGA^(D298N)-Stv13。将质粒pET28a-CpOGA^(D298N)-Stv13转化到大肠杆菌BL21(DE3)中进行诱导表达,获得了融合蛋白质CpOGA^(D298N)-Stv13。通过CpOGA^(D298N)特异性结合O-GlcNAc的能力及生物素-亲和素特异性亲和作用,设计了Far-Western blot(Far-WB)用于检测蛋白质O-GlcNAc修饰,利用sOGT(short form O-GlcNAc transferase)、去O-GlcNAc修饰sOGT、细胞裂解液样本及人肝细胞核因子1A(hepatocyte fuclear factor 1A,HNF1A)对该方法进行验证。本研究成功构建了一种蛋白质O-GlcNAc修饰检测方法,耗时相对O-GlcNAc特异性抗体缩短至5~7 h,丰富了蛋白质O-GlcNAc修饰的检测方法,为其后续研究奠定了基础。 展开更多
关键词 氧连接的β-N-乙酰葡萄糖胺修饰 CpOGA^(D298N)-Stv13 生物素 Far-Western blot
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^(177)Lu-DTPA-BIS-BIOTIN的制备及正常鼠体内生物分布 被引量:1
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作者 邓新荣 杜进 罗志福 《核化学与放射化学》 CAS CSCD 北大核心 2010年第3期184-188,共5页
研究了DTPA-BIS-BIOTIN的177Lu标记方法,优化了标记条件,并进行了标记物在正常小鼠体内分布实验。在最佳标记条件下(DTPA-BIS-BIOTIN 25μg,标记介质pH=4.5,80℃反应20 min),177Lu-DTPA-BIS-BIOTIN标记率大于99.0%,室温下放置96 h,标记... 研究了DTPA-BIS-BIOTIN的177Lu标记方法,优化了标记条件,并进行了标记物在正常小鼠体内分布实验。在最佳标记条件下(DTPA-BIS-BIOTIN 25μg,标记介质pH=4.5,80℃反应20 min),177Lu-DTPA-BIS-BIOTIN标记率大于99.0%,室温下放置96 h,标记物体外稳定性良好。正常小鼠体内分布实验结果表明,177Lu-DTPA-BIS-BIOTIN在血液中清除快,主要浓集于肝、脾和肾,经肾脏排泄。本研究为进一步采用177Lu-DTPA-BIS-BIOTIN进行肿瘤预定位显像及治疗研究提供了实验基础。 展开更多
关键词 177Lu DTPA-BIS-biotin 放射性标记 生物分布
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生物素靶向显影探针Biotin-S-S-Rhodol对乳腺癌细胞的靶向显影作用
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作者 吴碧娟 周杏子 +2 位作者 孙婧雯 谭翠雯 吴新荣 《南方医科大学学报》 CAS CSCD 北大核心 2017年第1期124-129,共6页
目的对新型生物素靶向显影探针(Biotin-S-S-Rhodol,3a)的靶向显影性能进行分析。方法采用紫外吸收光谱和荧光光谱分析谷胱甘肽(GSH)处理后3a的光谱特性;采用不同浓度GSH处理3a,荧光光谱分析3a对GSH的敏感性;采用流式细胞术和荧光倒置显... 目的对新型生物素靶向显影探针(Biotin-S-S-Rhodol,3a)的靶向显影性能进行分析。方法采用紫外吸收光谱和荧光光谱分析谷胱甘肽(GSH)处理后3a的光谱特性;采用不同浓度GSH处理3a,荧光光谱分析3a对GSH的敏感性;采用流式细胞术和荧光倒置显微镜观察生物素预处理前后MCF-7细胞、MDA-MB-231细胞和Hs 578Bst细胞对3a的摄取率和靶向显影性能;四甲基偶氮唑盐比色法(MTT)初步分析3a对MCF-7细胞、MDA-MB-231细胞和Hs 578Bst细胞的毒性。结果 3a的最强吸收峰在510 nm处,在544 nm处荧光发射信号最强;荧光光谱结果显示随着GSH浓度(0~6 mmol/L)处理浓度提高,544 nm波长处的荧光强度升高;MDA-MB-231、MCF-7细胞对3a的摄取率明显高于Hs 578Bst细胞;3a能实现乳腺癌细胞专一性成像,成像清晰;2~20μmol/L 3a对人正常乳腺细胞无明显毒性,可在一定程度上抑制MCF-7细胞和MDA-MB-231细胞存活。结论 3a能通过生物素介导专一靶向乳腺癌细胞,成像清晰,对正常乳腺细胞毒性极低,有一定的抑制乳腺癌细胞存活作用。 展开更多
关键词 biotin-S-S-Rhodol 生物素 罗丹明 二硫键 靶向显影 乳腺癌
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奥曲肽-葡聚糖-亲和素的偶联及其与^(177)Lu-DTPA-BIS-BIOTIN的体外结合
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作者 邓新荣 杜进 +2 位作者 翟士桢 沈亦佳 罗志福 《同位素》 CAS 2011年第3期146-150,共5页
以葡聚糖为载体,奥曲肽为导向分子合成了生长抑素配体化合物奥曲肽-葡聚糖-亲和素(Tyr3-oct-reotide-dxtran 40-avidin,TOC-Dx40-Av);在体外模拟肿瘤预定位二步法以177Lu-DTPA-BIS-BIOTIN对TOC-Dx40-Av培养的PANC-1细胞的结合特性进行... 以葡聚糖为载体,奥曲肽为导向分子合成了生长抑素配体化合物奥曲肽-葡聚糖-亲和素(Tyr3-oct-reotide-dxtran 40-avidin,TOC-Dx40-Av);在体外模拟肿瘤预定位二步法以177Lu-DTPA-BIS-BIOTIN对TOC-Dx40-Av培养的PANC-1细胞的结合特性进行了研究。将长满人源胰腺癌细胞PANC-1的24孔板置于含有TOC-Dx40-Av的缓冲液中培养,2 h后洗去上清液,再用含不同浓度177Lu-DTPA-BIS-BIOTIN(177Lu-DT-PA-BIS-BIOTIN的摩尔质量范围为48.8~391 pmol)的缓冲液继续培养细胞,使177Lu-DTPA-BIS-BIOTIN与细胞上的亲和素结合,测定细胞上结合的放射性计数,考察TOC-Dx40-Av与177Lu-DTPA-BIS-BIOTIN的结合特性以评价合成的大分子亲和素连接物的活性。实验结果显示,奥曲肽-葡聚糖-亲和素的化学纯度>99%,其中亲和素的含量为6.46 g/L。体外细胞结合实验结果表明,177Lu-DTPA-BIS-BIOTIN能快速与细胞上连接的亲和素结合,生物素与亲和素的摩尔比约为1∶1达到平衡。 展开更多
关键词 177Lu-DTPA-BIS-biotin 亲和素 葡聚糖 奥曲肽 偶联
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姜黄素-生物素偶联物的合成及抗肿瘤活性研究
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作者 马红艳 王立强 《合成化学》 CAS 2024年第3期216-224,共9页
为进一步开发安全有效的抗口腔癌药物,利用酰基化法及羧氨缩合法制备一系列姜黄素类衍生物,采用药物拼合原理,使姜黄素连接具有一定抗肿瘤活性及靶向性的生物素,合成一系列姜黄素-生物素偶联物(目标化合物2、4、5),其结构经^(1)H NMR、^... 为进一步开发安全有效的抗口腔癌药物,利用酰基化法及羧氨缩合法制备一系列姜黄素类衍生物,采用药物拼合原理,使姜黄素连接具有一定抗肿瘤活性及靶向性的生物素,合成一系列姜黄素-生物素偶联物(目标化合物2、4、5),其结构经^(1)H NMR、^(13)C NMR和HR-MS(ESI)确证。采用四甲基偶氮唑蓝(MTT)法检测目标化合物对人口腔表皮样癌细胞(KB细胞)增殖的抑制作用。结果显示:化合物2在作用24 h及48 h时对KB细胞的IC_(50)分别是40.82μmol/L和26.23μmol/L,提示其抗肿瘤活性优于姜黄素。化合物4在作用24 h及48 h时对KB细胞的IC_(50)分别是39.83μmol/L和51.24μmol/L,提示在作用24 h时,其抗肿瘤活性优于原药姜黄素。 展开更多
关键词 姜黄素 生物素 药物拼合原理 偶联物 四甲基偶氮唑蓝 抗肿瘤活性
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建立一种基于BAS化学发光技术检测血清β-hCG,Prog水平的抗生物素干扰方法
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作者 陈龙 郑详武 《现代检验医学杂志》 CAS 2024年第1期141-145,共5页
目的在基于生物素-链霉亲和素(biotin-avidin/streptavidin,BAS)的化学发光技术检测人绒毛膜促性腺激素β亚基(β-human chorionic gonadotropin,β-hCG)和孕酮(progesterone,Prog)时,建立一种简易、有效的抗生物素干扰方法。方法采用... 目的在基于生物素-链霉亲和素(biotin-avidin/streptavidin,BAS)的化学发光技术检测人绒毛膜促性腺激素β亚基(β-human chorionic gonadotropin,β-hCG)和孕酮(progesterone,Prog)时,建立一种简易、有效的抗生物素干扰方法。方法采用两种浓度链霉亲和素磁珠(streptavidin coated magnetic micro particles,M)检测不同生物素浓度的高、中、低水平的β-hCG和Prog血清,通过回收试验评价两种浓度M的抗生物素干扰能力以及采用低浓度M的校准曲线时高浓度M检测的准确度。结果①β-hCG和Prog的抗生物素干扰能力在低浓度M(0.72 mg/ml)时分别为100和25 ng/ml,在高浓度M(1.44 mg/ml)时分别为500和50 ng/ml。②使用和低浓度M相同的校准曲线时,高浓度M对于生物素浓度在500 ng/ml以下的β-hCG三个水平的回收率均在90%~110%之间;对于生物素浓度在50 ng/ml以下的高、中水平的Prog,其回收率在90%~110%之间。结论在基于BAS化学发光技术检测血清β-hCG和Prog时,采用高浓度M(1.44 mg/ml)是一种简易、有效且可靠的抗生物素干扰方法。 展开更多
关键词 生物素 链霉亲和素磁珠 人绒毛膜促性腺激素β亚基 孕酮
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邻近标记技术在弓形虫蛋白质组学研究中的应用进展
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作者 潘明 李龙娇 +1 位作者 葛层层 黄思扬 《中国兽医杂志》 CAS 北大核心 2024年第5期101-106,共6页
弓形虫编码数量众多的分泌蛋白,储存在微线体、棒状体和致密颗粒等虫体特有的细胞器中,于虫体入侵宿主细胞前后分泌到不同部位,并在虫体的感染、寄生和致病过程中发挥重要作用,对这些分泌蛋白的鉴定和功能研究是弓形虫致病机制研究中的... 弓形虫编码数量众多的分泌蛋白,储存在微线体、棒状体和致密颗粒等虫体特有的细胞器中,于虫体入侵宿主细胞前后分泌到不同部位,并在虫体的感染、寄生和致病过程中发挥重要作用,对这些分泌蛋白的鉴定和功能研究是弓形虫致病机制研究中的热点和难点。传统的蛋白质组学技术在弓形虫亚细胞器的分离和组分鉴定上存在样品纯化困难和蛋白质组学信息覆盖率低等不足,且该技术在检测瞬时的或较弱的蛋白质相互作用时灵敏性较低。近年来,快速发展的邻近标记技术(PL)克服了传统技术的局限性。PL是将具有特定催化活性的工具酶与诱饵蛋白进行融合,进而添加生物素或生物素苯酚对诱饵蛋白邻近的靶蛋白进行生物素酰化标记的一门技术。该技术整合了酶促反应效率高的优点,可将特定空间内的蛋白进行高效标记,并可检测较弱的蛋白质相互作用,近年来在生物学研究中被广泛使用。本文对基于生物素连接酶(BirA)和抗坏血酸过氧化物酶(APEX)催化的PL在弓形虫蛋白质组学研究中的应用进行阐述,介绍2种标记方法在弓形虫分泌蛋白的挖掘和蛋白质相互作用研究中的贡献,为弓形虫致病机制的研究和弓形虫病的防控提供参考。 展开更多
关键词 邻近标记技术(PL) 弓形虫 蛋白质组学 生物素连接酶(BirA) 抗坏血酸过氧化物酶(APEX)
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硫化氢介导的S-巯基化修饰及其化学检测技术
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作者 张珍 全心雨 唐志书 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2024年第1期44-53,共10页
硫化氢(hydrogen sulfide, H_(2)S)是继一氧化氮和一氧化碳之后的第3种内源性气体信号分子,通过影响细胞信号通路调节机体各个系统,具有广泛的生理和病理作用。近年的研究发现,H2S的作用主要通过对靶蛋白进行S-巯基化修饰,改变其结构,... 硫化氢(hydrogen sulfide, H_(2)S)是继一氧化氮和一氧化碳之后的第3种内源性气体信号分子,通过影响细胞信号通路调节机体各个系统,具有广泛的生理和病理作用。近年的研究发现,H2S的作用主要通过对靶蛋白进行S-巯基化修饰,改变其结构,影响其活性、稳定性以及蛋白质之间互相作用,进而调控细胞内信号通路及相关生物学过程。本文基于国内外对S-巯基化修饰的研究,主要综述了:S-巯基化修饰的研究现状,详细总结了目前已揭示S-巯基化修饰及其具体半胱氨酸(cysteine, Cys)位点的研究,并进一步总结了S-巯基化修饰与S-亚硝基修饰之间的关系;S-巯基化修饰的反应类型,3种化学检测(马来酰亚胺法、改良生物素转换法和标记转换法)方法的检测原理和特点,通过S-巯基化修饰检测的条件和应用范围,将这3种方法进行对比,并对各方法在检测过程中应注意的事项进行了讨论。根据作者在S-巯基化修饰研究方面积累的经验,重点阐述马来酰亚胺法检测过程中,细胞和组织样品的制备及其较详细的实验步骤。此外,本文还讨论了当前S-巯基化修饰检测方法存在的不足及该领域未来亟待解决的问题,为S-巯基化修饰的相关研究提供参考。 展开更多
关键词 硫化氢 S-巯基化修饰 马来酰亚胺法 改良生物素转换法 标记转换法
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Effects of a rumen protected B vitamin blend substituted for biotin upon milk production and component yield in lactating dairy cows 被引量:2
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作者 Essi Evans David T. Mair 《Open Journal of Animal Sciences》 2013年第2期93-98,共6页
Results from 4 switchback field trials involving 608 cows were combined to assess the effects of a protected B vitamin blend (BVB) vs 10 mg of unprotected biotin upon milk yield (kg), fat %, protein %, fat yield (kg) ... Results from 4 switchback field trials involving 608 cows were combined to assess the effects of a protected B vitamin blend (BVB) vs 10 mg of unprotected biotin upon milk yield (kg), fat %, protein %, fat yield (kg) and protein yield (kg) in primiparous and multiparous cows. Trials consisted of 3 DHIA periods executed in the order control-test-control. Cows from 45 to 300 days in milk (DIM) at the start of the experiment that were available for all 3 periods were included in the analysis. No diet changes other than the substitution of 3 grams/cow/day of the BVB for 10 mg of biotin during the test period occurred. Results from the two control periods were compared to results obtained during the test period by individual cow using a paired T test. Results for all cows showed that the provision of the BVB resulted in increased (P < 0.05) milk, fat percentage (%), protein %, fat yield and protein yield. Analysis by age revealed that milk production and milk protein yield were only improved in mature cows. Milk production had a negative effect upon the magnitude of the increase in milk components. The change in milk yield was greatest in early lactation and declined with DIM. Protein % and fat % increased with DIM in mature cows, but not in first lactation cows. Differences in fat yields between test and control feeding periods did not change with DIM, but the improvement in protein yield in mature cows declined with DIM. These results indicate that the BVB provided economically important advantages throughout lactation beyond those witnessed with biotin, but expected results would vary with cow age and stage of lactation. 展开更多
关键词 B VITAMIN BLEND biotin MILK Components
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A Simple Method Designed for the Separation of Biotinylated Ligate from Free Biotin 被引量:1
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作者 LI Tian yu, ZHOU Chang cheng, FANG Rui, QI Jie, ZHOU Hui and LI Wei (Department of Life Science, Jilin University, Changchun, 130023) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第4期72-74,共3页
IntroductionDuringtheprocesofbiotinlabeling,theseparationofbiotinylatereagentfrombiotiny-latedproteinisaness... IntroductionDuringtheprocesofbiotinlabeling,theseparationofbiotinylatereagentfrombiotiny-latedproteinisanessentialstep,especi... 展开更多
关键词 biotinylated Ligate biotin PROTEIN
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Establishment of Cell Free Conversion System With Biotin-labelled Recombinant PrP^(sen) Expressed in E.coli 被引量:1
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作者 JIN ZHANG JIAN-MEI GAO +7 位作者 FENG LI JUN HAN LAN CHEN BAO-YUN ZHANG XIAO-FAN WAMG WEI ZHOU YONG LIU XIAO-PING DONG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2006年第3期214-218,共5页
Objective To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope. Methods A hamster PrP protein (HaPrP) was expressed in E. coli and purified with HIS-tag affinity ch... Objective To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope. Methods A hamster PrP protein (HaPrP) was expressed in E. coli and purified with HIS-tag affinity chromatograph. After being labelled with biotin, HaPrP was mixed with PrP^sen preparation from scrapie strain 263K. Results Protease-resistant bands were detected after four-day incubation. Conclusion The new conversion model provides a reliable, easily handling, and environment-friendly method for studies of prion and transmissible spongiform encephalopathies. 展开更多
关键词 Transmissible spongiform eneephalopathies PRION biotin Cell free conversion E. coli
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Avidin-biotin system pretargeting radioimmunoimaging and radioimmunotherapy and its application in mouse model of human colon carcinoma 被引量:5
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作者 Gui-Ping Li Hui Zhang +2 位作者 Cheng-Mo Zhu, Jian Zhang Xu-Feng Jiang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第40期6288-6294,共7页
AIM: To evaluate the multi-step pretargeting radioimmunoimaging (RII) and radioimmunotherapy (RIT) in nude mice bearing human colon carcinoma with avidin-biotin system labeled with 153Sm.METHODS: Two- and three-step s... AIM: To evaluate the multi-step pretargeting radioimmunoimaging (RII) and radioimmunotherapy (RIT) in nude mice bearing human colon carcinoma with avidin-biotin system labeled with 153Sm.METHODS: Two- and three-step strategies for avidinbiotin system pretargeting techniques were established.In a three-step procedure, human colon carcinoma bearing nude mice were first injected with biotinylated monoclonal antibody (McAb-Bt) followed by cold avidin (Av) 48 h later and then 153Sm-DB2 24 h thereafter;whereas the twostep procedure consisted of injection of 153Sm-SA 48 h after pretargeting with biotinylated anti-CEA monoclonal antibody (CEA McAb-Bt). SPECT imaging and biodistribution were performed at 4, 24, 48, or 72 h after injection of 153Sm-labeled compounds. Five groups of nude mice subcutaneously grafted with human colon carcinoma were treated 3 d after grafting. One group received the injection with 100 μg CEA McAb-Bt followed by cold avidin (80 μg)after 2 d and 11.1 MBq 153Sm-DB2 after 1d. Four control groups were treated respectively with 11.1 MBq 153SmCEA McAb, 11.1 MBq 153Sm-nmIgG, 11.1 MBq 153Sm-DB2,100 Μl normal saline. Toxicity was evaluated by changes of leukocyte count, and the efficacy by variation in tumor volume. Histological analyses of tumors were performed.RESULTS: The three-step procedure allowed faster blood clearance and yielded higher tumor blood ratios (5.76 at4 h and 12.94 at 24 h) of the 153Sm-DB2. The tumor was clearly visualized at 4 h in y-imaging after the injection of 153Sm-DB2, while a significant accumulation of 153Sm-SA in the tumor was observed only 24 h after the injection and tumor blood ratios at 4 and 24 h were 1.00 and 2.03,respectively, in the two-step procedure. Pretargeting RIT and 153Sm-CEA McAb had a strong tumor-inhibiting effect.The tumor inhibitory rate was 80.67% and 78.44%,respectively, five weeks after therapy. Histopathological evidence also indicated radioactive damage in tumor tissues as necrosis of tumor cells, while in the other organs such as liver and kidney no radioactive damage was observed. Leukocyte counts showed significant decrease after treatment in groups of 153Sm-CEA Mc Ab and 153SmnmIgG.CONCLUSION: The two kinds of pretargeting strategies can elevate the target-to-nontarget ratio, decrease the blood background and shorten the imaging time compared to 153Sm-CEA McAb. Three-step pretargeting RIT is as efficient as 153Sm-CEA Mc Ab, but markedly less toxic. This study provides experimental evidence for the clinical application of pretargeting RII and RIT. 展开更多
关键词 抗生物素蛋白 放射免疫疗法 结肠癌 动物实验
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Post-Marketing Surveillance of Fixed Dose Combination of Methylcobalamin, Alpha Lipoic Acid, Folic Acid, Biotin, Benfotiamine &Vitamin B6-Nutripathy for the Management of Peripheral Neuropathy 被引量:1
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作者 Manish Maladkar Chitra Tekchandani Urja Dave 《Journal of Diabetes Mellitus》 2014年第2期124-132,共9页
Background: Peripheral neuropathy is a commonly encountered troublesome condition which is often disabling & worsens when left untreated. Traditional neuropathic pain medications primarily provide symptomatic reli... Background: Peripheral neuropathy is a commonly encountered troublesome condition which is often disabling & worsens when left untreated. Traditional neuropathic pain medications primarily provide symptomatic relief;however, the pathogenesis of nerve damage remains unresolved. Extensive literature survey reveals that patients with peripheral neuropathy experience significant benefits with the use of B-vitamins like methylcobalamin (B12), folic acid (B9), biotin (B7), benfotiamine (B1) and pyridoxine (B6). The other well documented antineuropathic agents include alpha lipoic acid, glutathione, omega fatty acids, myoinositol, certain trace elements, etc. Materials and Methods: A multicentre, prospective, open-label, non-comparative clinical study was carried out in 497 patients with peripheral neuropathy. A fixed dose combination of methylcobalamin, alpha lipoic acid (ALA), folic acid, biotin, benfotiamine & vitamin B6 capsule was orally administered once daily for 12 weeks. Results: Treatment led to significant reduction from baseline score in various neuropathy symptoms from the 4th week itself. After 12 weeks of treatment, the mean pain score declined by 78.0%, numbness by 92.1% and muscle weakness by 96.9%. Also, there was 96.0% & 99.2% reduction in tingling & burning sensation respectively. No serious adverse events were reported.Conclusion: The current study confirms that fixed dose combination of methylcobalamin, ALA, folic acid, biotin, benfotiamine & vitamin B6 is effective & well tolerated in the management of peripheral neuropathy. 展开更多
关键词 Peripheral NEUROPATHY METHYLCOBALAMIN Alpha Lipoic ACID Folic ACID biotin BENFOTIAMINE VITAMIN B6
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IgG-Biotin-Avidin-HRP信号转导探针结合免疫比色法快速检测克罗诺阪崎肠杆菌 被引量:2
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作者 叶玲娴 黄浩然 +4 位作者 柳露 吴遵义 黄建锋 赵广英 窦文超 《中国食品学报》 EI CAS CSCD 北大核心 2020年第7期237-243,共7页
本文建立了一种快速检测克罗诺阪崎肠杆菌的新型免疫比色法。用抗体修饰的磁球(MNPs-IgG)作为捕获探针分离、富集克罗诺阪崎肠杆菌,再通过免疫夹心法分别结合生物素标记的克罗诺阪崎肠杆菌抗体(Biotin-IgG)和亲和素标记的辣根过氧化物酶... 本文建立了一种快速检测克罗诺阪崎肠杆菌的新型免疫比色法。用抗体修饰的磁球(MNPs-IgG)作为捕获探针分离、富集克罗诺阪崎肠杆菌,再通过免疫夹心法分别结合生物素标记的克罗诺阪崎肠杆菌抗体(Biotin-IgG)和亲和素标记的辣根过氧化物酶(Avidin-HRP),形成的复合物与底物四甲基联苯胺(3,3′,5,5′-Tetramethylbenzidine,TMB)发生显色反应,经硫酸终止后,有色产物的吸光度值与克罗诺阪崎肠杆菌浓度的对数有良好的线性关系,在103~107CFU/mL范围内,线性方程为y=0.2353x-0.2307。本研究成功设计优化了基于比色法的克罗诺阪崎肠杆菌定量检测新方法,检测限为8.68×10^2CFU/mL(S/N=3),加标样品检出率96%,检测时间不超过2.5 h,为实际应用与商品化提供了理论支撑。 展开更多
关键词 信号转导探针 免疫磁性纳米颗粒 生物素亲和素系统 免疫比色法 食源性致病菌
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Determination of Biotin in Pharmaceutical Formulations by Potassium Permanganate-luminol-CdTe Nanoparticles Chemiluminescence System
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作者 TRAORE Zoumana Sékou SU Xing-guang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第4期604-608,共5页
A sensitive flow-injection chemiluminescence method was developed for the determination of biotin in the pharmaceutical formulations.The affinity between avidin and biotin was used to adsorb biotin on the polystyrene,... A sensitive flow-injection chemiluminescence method was developed for the determination of biotin in the pharmaceutical formulations.The affinity between avidin and biotin was used to adsorb biotin on the polystyrene,with subsequent quantification of biotin based on its ability to enhance the chemiluminescence(CL) signal generated by the redox reaction of potassium permanganate-luminol-CdTe nanoparticles CL system.The investigations prove that apart from 3-aminophthalate,the CdTe quantum dots(QDs) play both catalytic and emitter roles.Under optimum conditions,the linear range for the determination of biotin was 0.01―25 ng/mL with a detection limit of 7.3×10-3 ng/mL(S/N=3).The relative standard deviation of 5 ng/L biotin was 2.06%(n=7).The proposed method was used to determine the biotin concentration in the pharmaceutical formulations and the recovery was between 96.4% and 104%.The proposed method is simple,convenient,rapid and sensitive. 展开更多
关键词 FLOW-INJECTION CHEMILUMINESCENCE biotin CdTe nanoparticle
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A Sensitive Competitive ELISA for Determination of Biotin in Transformed Yeast Culture Media 被引量:1
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作者 YANGHong 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第4期201-206,共6页
Aim To develop a sensitive competitive ELISA for the determination of biotin in transformed yeast culture media.Methods The ELISA plate was firstly coated with Mycoplasma hyopneumoniae, and then successively incubated... Aim To develop a sensitive competitive ELISA for the determination of biotin in transformed yeast culture media.Methods The ELISA plate was firstly coated with Mycoplasma hyopneumoniae, and then successively incubated with rabbit ami-Mycoplasma hyopneumoniae serum and goat anti-rabbit IgG-biotin to form the solid biotin, which competed with the biotin in the solution (standard or sample) for the limited streptavidin-horse radish peroxidase conjugate. The standard calibration curve for biotin analysis was constructed in the range of 50-2000ng·L^-1. Results The detection limit for biotin was found to be 83 ng·L^-1 , which waa about 1000 times lower than the lowest determination concenlration in the reported ELISA for biotin analysis. The relative standard deviations for the spiked samples at biotin concerarations of 200 ng·L^-1, 500 ng·L^-1 , and 1000 ng·L^-1 were 24.87%, 6.15%, and 7.86%, respectively, with the average recovery of 101.13%. The wild yeast and its sixty-three transformed yeast culture media were applied to the developed ELISA for the determination of biotin. It was found that the biotin concentrations in more than 85 % of the tested samples were enhanced with different increase factors after transformation. Conclusion Utilization of Mycoplasma hyopnetunoniae as the coating protein improves the precision and accmacy oftbe ELISA assay, which might be used for the biotin assay in other media. 展开更多
关键词 维生素H 酵母培养基 ELISA 亲和力 药品检验
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Synthesis of Biotinylated Galiellalactone Analogues
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作者 Zilma Escobar Martin Johansson +2 位作者 Anders Bjartell Rebecka Hellsten Olov Sterner 《International Journal of Organic Chemistry》 2014年第4期225-235,共11页
Two biotinylated derivatives of the fungal metabolite galiellalactone (1) were synthesized in order to facilitate the investigation of the molecular mechanism of action of the galiellalactonoids. Galiellalactone is a ... Two biotinylated derivatives of the fungal metabolite galiellalactone (1) were synthesized in order to facilitate the investigation of the molecular mechanism of action of the galiellalactonoids. Galiellalactone is a STAT3-signaling inhibitor that inhibits growth in vitro as well as in vivo of prostate cancer cells expressing activated STAT3. To provide a suitable point of attachment for biotin, the 8-hydroxymethyl derivative (3) and its 7-phenyl analogue 4 were synthesized by a modified tandem Pd-catalysed carbonylation and intramolecular vinyl allene Diels-Alder procedure previously developed. The two primary alcohols obtained, 3 and 4, were coupled to biotin as the 6-aminohexanoic acid amide, activated as the acid chloride, yielding the derivatives 5 and 6. 展开更多
关键词 STAT3 Galiellalactone biotin SYNTHESIS
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