结核杆菌D29噬菌体几丁质酶基因的表达及功能研究  

Expression and Function Analysis of Mycobacteriophage D29 Chitinase Gene

作　　者：朱成钢[1] 丁志山 

机构地区：[1]浙江大学生命科学学院生物化学研究所,杭州310029 [2]浙江省中医学院生命科学系,杭州310053

出　　处：《生物化学与生物物理进展》2005年第8期753-757,共5页Progress In Biochemistry and Biophysics

摘　　要：噬菌体一般通过表达内溶素来降解宿主菌细胞壁上的肽聚糖.用PCR技术从结核杆菌D29噬菌体基因组中克隆了gene10,并使其在大肠杆菌中得到了高效表达,蛋白质C端带有6×His.用镍柱亲和纯化了大肠杆菌表达的gp10蛋白可溶性部分.活性测定表明,gp10不但具有几丁质酶活性,还具有溶菌酶活性,是一种双功能的酶.耻垢杆菌经gp10作用后,其生长受到抑制,扫描电镜观察发现部分耻垢杆菌被降解.说明与其他种类噬菌体降解细胞壁的方式不同,D29噬菌体可能利用gp10的溶菌酶活性使结核杆菌细胞壁降解.这有助于揭示结核杆菌噬菌体与其宿主的相互作用机制,是关于噬菌体几丁质酶的首次报道.Endolysins or lysins are cell-wall-hydrolysing enzymes synthesized during late gene expression in the lyric cycle of bacteriophage mutiplication and enable the release of progeny virions from infected cells through degradation of the bacterial peptidoglycan. The gene10 was amplified from purified DNA of Mycobacteriophage D29 by using PCR and was expressed with 6×His tag in E.coli. The soluble portion of recombinant protein was purified by Ni-NTA column and the activity was detected. The results showed that gp10 is a bi-functional enzyme, has chitinase and lysozyme activities. The cell wall degradation was observed by SEM.

关 键 词：噬菌体 结核杆菌 几丁质酶 

分 类 号：Q786[生物学—分子生物学] S855.2[农业科学—临床兽医学]