重组人溶菌酶理化及生物学特性的鉴定  

Characterization of recombinant human lysozyme expressed in the mammary glands of transgenic mice

作　　者：李国才[1] 孙怀昌[2] 钱科[2] 居杏珠[1] 陈瑾[1] 张泉[2] 朱秋菊[2] 

机构地区：[1]扬州大学医学院,江苏扬州225001 [2]扬州大学兽医学院,江苏扬州225009

出　　处：《中国乳品工业》2005年第4期11-14,共4页China Dairy Industry

基　　金：江苏省高新技术(BJ2001315)资助项目;国家教育部骨干教师培养计划项目(2000)

摘　　要：为了研究转基因小鼠乳腺表达的重组人溶菌酶(rhLYZ)的理化特性及抑菌活性,将适当稀释的含rhLYZ的母鼠乳汁置于60,72,85,100℃的水浴中,每隔0,1,3,5,10,15,20,30min取样,用微球菌溶解法测定rhLYZ的热稳定性;将稀释乳样的pH值调节为2.0,4.0,5.0,7.4,9.0和10.0,37℃作用30min后检测乳样中rhLYZ的活性;将不同的金属离子加入乳样中,使其终浓度为10mmol/L,然后测定金属离子对rhLYZ活性的影响;用培养的革兰氏阳性菌、革兰氏阴性菌及真菌涂布琼脂平板,以平板扩散法检测乳样中rhLYZ抑菌谱,在此基础上挑选敏感菌株进行定量抑菌试验。结果表明,转基因小鼠乳腺表达的rhLYZ与人乳中天然hLYZ都具有很强的热稳定性、相似的pH值活性范围和金属离子敏感性,对多种革兰阳性及阴性细菌具有不同程度的抑菌作用。To study the physical and chemic properties and anti-bacterial activit ies of recombinant human lysozyme (rhLYZ) expressed in mammary glands of the tra nsgenic mice, the milk samples and human colostrum were subjected to heat treatm ent at 60, 72, 85 or 100 ℃ for 1, 3, 5, 10, 15, 20 or 30 min for comparison of their similarity in thermal stability. pH of the two kinds of milk samples were adjusted to 2, 4, 5, 7.4, 9 or 10 followed by incubation at 37 ℃ for 30 min for detection of their pH stability. In addition, the two kinds of milk samples wer e mixed with solutions containing different ions at the final concentration of 1 0 mmol/L. The lysozyme activities in the samples treated using the above methods were detected using micrococcal lysis assay, which showed that rhLYZ expressed in transgenic mice milk had similar thermal, pH and ions stability to natural hL YZ in human colostrums.11 different bacterial strains and 1 fungal strain were a ssayed by agar diffusion test for bacteriocidal spectrums of rhLYZ expressed in the milk of transgenic mice and natural hLYZ in human colostrum. The results sho wed that both rhLYZ and natural hLYZ shared almost the same bactericidal spectru m, indicating authentic folding, post-translational modification and thus activi ty of the expressed rhLYZ.

关 键 词：转基因小鼠 d1LYZ 稳定性 抑菌活性 

分 类 号：Q556[生物学—生物化学]