基于LTQ-Orbitrap液相色谱-质谱联用技术的乳源乳清蛋白组分的差异性研究  

Study on Differences of Milk Proteins by Linear Trap Quadropole-Orbitrap LC-MS/MS

作　　者：徐明芳[1] 戴金凤[1] 向明霞[1] 成希飞[1] 曾晓琮 万丛庆 周卫军[1] 

机构地区：[1]暨南大学生命科学技术学院,广州510632

出　　处：《分析化学》2014年第4期501-506,共6页Chinese Journal of Analytical Chemistry

基　　金：广东省科技计划项目(No.2009B011300003)资助

摘　　要：利用LTQ Orbitrap XL组合型傅立叶变换高分辨质谱系统分析了乳源蛋白主要组分肽指纹图谱。对南方水牛乳与不同来源的乳清蛋白的氨基酸序列研究结果表明,乳清蛋白经酶解后主要为α-乳白蛋白(α-La)和β-乳球蛋白(β-Lg)组分,乳清蛋白肽质指纹谱的分析显示水牛乳与荷斯坦奶乳清蛋白α-La氨基酸发生变异的比率明显少于山羊奶乳清蛋白α-La,说明荷斯坦奶α-La和水牛乳α-La的差异更小,同源性更强;而水牛乳β-Lg与荷斯坦乳β-Lg氨基酸发生变异的部位比率要多于山羊奶,水牛乳β-Lg与山羊奶同源性更强;乳源酪蛋白酶解后的肽段主要组分为αs1-CN,β-CN,κ-N,通过对水牛乳酪蛋白的氨基酸序列的差异性分析,不同品种的乳源酪蛋白的氨基酸序列明显存在差异。与乳清蛋白相比,奶牛品种差异导致乳蛋白发生氨基酸差异现象更显著,酪蛋白的氨基酸序列对比表明,水牛奶酪蛋白与山羊奶酪蛋白比与乳牛酪蛋白的差异更大。Abstract The peptide mass fingerpringting differences of whey（a-La） and （β-Lg） and caseins （asl-CN, β-CN, K-CN） components by enzymatic hydrolysis of milk protein from the Southern water buffalo compared with goat and Holstein milk were analyzed by using the linear trap quadropole （LTQ） Orbitrap XL mass spectrometer with high resolution. Results showed that peptide mass fingerpringting differences of a-La amino acid mutation in Southern water buffalo and Holstein milk whey protein were lower than in the goat milk whey protein, however, the differences of of β-Lg amino acid mutation in Southern water buffalo and Holstein milk whey protein were higher than that in the goat milk whey protein. In contrast , the amino acids sequence differences of caseins （asl-CN, β-CN, K-CN ） components compared within three different milk-producing species changed significantly than in whey protein and indicated that the peptide mass fingerprinting differences of milk protein, especially impacted greatly on casein other than in whey protein, result from species variety.

关 键 词：LTQ Orbitrap质谱 乳源蛋白 酪蛋白 乳清蛋白 肽质指纹谱 差异性 

分 类 号：O657.63[理学—分析化学] TS252.7[理学—化学]