Isolation of lactoferrin from milk of different species:: Calorimetric and antimicrobial studies
Isolation of lactoferrin from milk of different species:: Calorimetric and antimicrobial studies
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DOI：
10.1016/j.cbpb.2008.02.005
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发表时间：
2008-05-01
影响因子：
2.2
通讯作者：
Evans, Robert W.
中科院分区：
文献类型：
--
作者：
Conesa, Celia;Sanchez, Lourdes;Evans, Robert W.
乳铁蛋白（LF）是一种结合铁的糖蛋白，存在于哺乳动物的不同生物体液和中性粒细胞中。它被认为参与了许多功能，包括对病原体的保护。本研究尝试用离子交换色谱法（SP-Sepharose）对以下动物的乳铁蛋白进行纯化：绵羊（Ovis aries）、山羊（Capra hircus）、骆驼（Camelus bactrianus）、羊驼（Lama pacos）、大象（Elephas maximus）和灰海豹（Halichoerus grypus），以及人类（Homo sapiens）。除灰海豹牛奶外，其余牛奶均含有乳铁蛋白。用差示扫描量热法（DSC）研究了纯化乳铁蛋白在天然和铁饱和形式下的热稳定性。饱和乳铁蛋白的最高温度、起始温度和变性焓变均高于其天然形态，表明铁结合后蛋白质结构的稳定性增加。人类乳铁蛋白的耐热性最强，其他乳铁蛋白的耐热性不同程度，大象乳铁蛋白的耐热性最差。研究了不同分离得到的乳铁蛋白对大肠杆菌O157:H7的抑菌活性。最小抑制浓度（mic）通过测量吸光度在620环确定。测定了最低抑菌浓度（MBCs），发现骆驼乳铁蛋白对大肠杆菌O157:H7的抑菌活性最高，而羊驼和人乳铁蛋白的抑菌活性最低。(C) 2008爱思唯尔公司版权所有。
Lactoferrin (LF) is an iron-binding glycoprotein found in different biological fluids of mammals and in neutrophils. It has been proposed to be involved in many functions, including protection from pathogens. In this work, purification of lactoferrin using an ion-exchange chromatography (SP-Sepharose) was attempted for the milk of the following animals: sheep (Ovis aries), goat (Capra hircus), camel (Camelus bactrianus), alpaca (Lama pacos), elephant (Elephas maximus) and grey seal (Halichoerus grypus), as well as human (Homo sapiens). Lactoferrin was identified in all the milks apart from that from grey seal. The thermal stability of the purified lactoferrins, in their native and iron-saturated forms, was studied by differential scanning calorimetry (DSC). Maximum temperature, onset temperature and enthalpy change of denaturation were higher when lactoferrins were saturated with iron than in their native form, indicating an increase in the stability of the protein structure upon iron-binding. Human lactoferrin was found to be the most heat-resistant and the other lactoferrins presented different degrees of thermoresistance, that of elephant being the least resistant. The antimicrobial activity of the different isolated lactoferrins was investigated against Escherichia coli O157:H7. The minimal inhibitory concentrations (MICs) were determined by measuring the absorbance at 620 rim. The minimum bactericidal concentrations (MBCs) were also measured and it was found that camel lactoferrin was the most active lactoferrin against E. coli O157:H7, whereas alpaca and human lactoferrins were the least active. (C) 2008 Elsevier Inc. All rights reserved.