Gene-Engineered Hydrophobilization to Alter the Bactericidal Activity of Lysozyme
Gene-Engineered Hydrophobilization to Alter the Bactericidal Activity of Lysozyme
复制标题
基因工程疏水化改变溶菌酶的杀菌活性
DOI：
10.1106/q11w-f3ed-u05c-4gur
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发表时间：
2000
影响因子：
1.7
通讯作者：
Y. Imanishi
中科院分区：
文献类型：
--
作者：
Yoshihiro Ito;O. Kwon;M. Ueda;A. Tanaka;Y. Imanishi
利用重组DNA技术，将具有不同链长的疏水多肽脯氨酸连接到人溶菌酶的c端。人溶菌酶的疏水性随着脯氨酸链长度的增加而增加。圆二色光谱分析显示，聚脯氨酸链的掺入对溶菌酶二级结构没有明显的扰动。虽然野生型人溶菌酶的杀菌活性仅限于革兰氏阳性菌（M. luteus和B. subtilis），但突变型溶菌酶对革兰氏阴性菌（E. coli和P. aeruginosa）也有杀菌活性，且活性随着突变型酶疏水性的增加而增强。大肠杆菌磷脂脂质体实验表明，突变体溶菌酶增强了脂质体含量的释放，并随着疏水性的增加而增加。突变型酶疏水性的增强可能诱导溶菌酶与大肠杆菌外膜相互作用，进而渗透到内膜，导致杀菌活性的增强。
The hydrophobic polypeptide, polyproline, which has different chain lengths, was connected to the C-terminus of human lysozyme by recombinant DNA techniques. The hydrophobicity of human lysozyme increased with the increasing length of the polyproline chain. No significant perturbation of the secondary structure of lysozyme by incorporation of the polyproline chain was observed by circular dichroism spectroscopy. Although the bactericidal activity of wild-type human lysozyme is limited to Gram-positive bacteria (M. luteus and B. subtilis), the mutant lysozymes showed bactericidal activity to Gram-negative bacteria (E. coli and P. aeruginosa), and the activity increased with the increasing hydrophobicity of the mutant enzyme. Experiments with E. coli phospholipid liposomes revealed that the mutant lysozymes enhanced the release of the liposome contents, and this release increased with the increase of hydrophobicity. The increased hydrophobicity of the mutant enzyme may induce the interaction of lysozyme with the outer membrane E. coli and subsequent penetration into the inner membrane, resulting in the increase of bactericidal activity.