脂肪酸在哺乳动物的能量代谢中发挥着至关重要的作用，同时也是合成细胞膜磷脂和其他生物活性化合物的重要物质.脂肪酸在血液中的溶解度很低，主要以与蛋白质结合状态存在，白蛋白是游离脂肪酸的主要运输者和储存者.因此，研究脂肪酸和白蛋白的相互作用具有非常重要的医学和生物学意义.本文主要利用基于核磁共振（NMR）的组氨酸选择性检测技术T2W-RD-WaterLOGSY研究天然同位素丰度人血清白蛋白（HSA）与脂肪酸的相互作用，结果发现脂肪酸结合前后，HSA的特征组氨酸谱图变化明显，部分组氨酸信号的相对强度随脂肪酸浓度的增加而不断减小，相应的滴定曲线分析表明HSA表面有两个强的脂肪酸结合位点.此外，部分谱线的化学位移变化说明HSA和脂肪酸的强结合还会引发HSA相应的构象变化.
高东莉
,
孙鹏
,
王倩文
,
刘买利
,
张许
. 运用NMR研究白蛋白与脂肪酸的相互作用[J]. 波谱学杂志, 2018
, 35(3)
: 338
-344
.
DOI: 10.11938/cjmr20182641
Fatty acids are important substrates for the synthesis of membrane phospholipids and other bioactive compounds, and thus play vital roles in mammalian energy metabolism. Fatty acids often bind to proteins in the blood. Albumin is a major carrier and depot of free fatty acids. In this paper, the interactions between human serum albumin (HSA) and fatty acids were studied using nuclear magnetic resonance (NMR)-based histidine selective detection technology T2W-RD-WaterLOGSY. The spectra of HSA before and after fatty acids binding were compared. It was found that signals of the characterized His in HSA changed significantly with the addition of fatty acids. Two high-affinity binding sites between the HSA and fatty acids were identified from the titration curve. It was also demonstrated that binding to fatty acids could induce conformation changes for HSA.
[1] SLEEP D. Albumin and its application in drug delivery[J]. Expert Opin Drug Deliv, 2015, 12(5):793-812.
[2] KENDALL F E. Studies on human serum proteins[J]. J Biol Chem, 1941, 138(1):97-109.
[3] SUGIO S, KASHIMA A, MOCHIZUKI S, et al. Crystal structure of human serum albumin at 2.5Å resolution[J]. Protein Eng Des Sel, 1999, 12(6):439-446.
[4] FREDRICKSON D S, JR R S G. The metabolism of albumin-bound C14-labeled unesterified fatty acids in normal human subjects[J]. J Clin Invest, 1958, 37(11):1504-1515.
[5] LIAO S M, DU Q S, MENG J Z, et al. The multiple roles of histidine in protein interactions[J]. Chem Cent J, 2013, 7(1):44.
[6] SCHNEIDER F. Histidine in enzyme active centers[J]. Angew Chem Int Ed Engl, 1978, 17(8):583-592.
[7] BLINDAUER C A, HARVEY I, BUNYAN K E, et al. Structure, properties, and engineering of the major zinc binding site on human albumin[J]. J Biol Chem, 2009, 284(34):23116-23124.
[8] KANEKO K, CHUANG V T, MINOMO A, et al. Histidine146 of human serum albumin plays a prominent role at the interface of subdomains IA and ⅡA in allosteric ligand binding[J]. IUBMB Life, 2011, 63(4):277-285.
[9] BHATTACHARYA A A, GRüNE T, CURRY S. Crystallographic analysis reveals common modes of binding of medium and long-chain fatty acids to human serum albumin[J]. J Mol Biol, 2000, 303(5):721-732.
[10] DAI C Y, ZHANG Z T, LIU M L, et al. Application of NMR in the studies of structure and interactions of α-synuclein[J]. Chinese J Magn Reson, 2016, 33(1):153-167. 戴晨晔, 张则婷, 刘买利, 等. NMR在α-Synuclein的结构及相互作用研究中的应用[J]. 波谱学杂志, 2016, 33(1):153-167.
[11] CHENG K, YAO C D, XU G H, et al. Interaction of GB1 with metal ions studied by NMR spectroscopy[J]. Chinese J Magn Reson, 2018, 35(1):1-7. 成凯, 姚陈叠, 徐国华, 等. GB1与金属离子相互作用的NMR研究[J]. 波谱学杂志, 2018, 35(1):1-7.
[12] SIMARD J R, ZUNSZAIN P A, HAMILTON J A, et al. Location of high and low affinity fatty acid binding sites on human serum albumin revealed by NMR drug-competition analysis[J]. J Mol Biol, 2006, 361(2):336-351.
[13] HAMILTON J A. NMR reveals molecular interactions and dynamics of fatty acid binding to albumin[J]. Biochim Biophys Acta, 2013, 1830(12):5418-5426.
[14] DALVIT C, PEVARELLO P, TATÒ M, et al. Identification of compounds with binding affinity to proteins via magnetization transfer from bulk water[J]. J Biomol NMR, 2000, 18(1):65-68.
[15] DALVIT C, FOGLIATTO G, STEWART A, et al. WaterLOGSY as a method for primary NMR screening:practical aspects and range of applicability[J]. J Biomol NMR, 2001, 21(4):349-359.
[16] SUN P, JIANG X W, JIANG B, et al. Biomolecular ligands screening using radiation damping difference WaterLOGSY spectroscopy[J]. J Biomol NMR, 2013, 56(3):285-290.
[17] CHEN Y, SUN P, LIU M L, et al. Effects of metal ions on human serum albumin studied by radiation damping water-ligand observed via gradient spectroscopy[J]. Chinese J Magn Reson, 2017, 34(3):266-274. 陈瑶, 孙鹏, 刘买利, 等. 离子对人血清白蛋白影响的1H NMR研究[J]. 波谱学杂志, 2017, 34(3):266-274.
[18] 陈瑶. 人血清白蛋白与配体之间相互作用的核磁共振研究[D]. 武汉:中国科学院武汉物理与数学研究所, 2016.
[19] FANALI G, DI MASI A, TREZZA V, et al. Human serum albumin:from bench to bedside[J]. Mol Aspects Med, 2012, 33(3):209-290.
[20] WOSILAIT W D, SOLER-ARGILAGA C. A theoretical analysis of the multiple binding of palmitate by bovine serum albumin:The relationship to uptake of free fatty acids by tissues[J]. Life Sci, 1975, 17(1):159-166.
[21] VAN DER VUSSE G J. Albumin as fatty acid transporter[J]. Drug Metab Pharmacokinet, 2009, 24(4):300-307.
