鸡毒霉形体HS株pMGA多基因族序列分析  

Sequence Analysis of the pMGA Multigene Family of Mycoplasma Gallisepticum Strain HS

作　　者：沈青春[1] 毕丁仁[1] 翁长江[1] 李自力[1] 石德时[1] 许青荣[1] 程峰[1] 

机构地区：[1]华中农业大学畜牧兽医学院,湖北武汉430070

出　　处：《兽医大学学报》2003年第3期243-246,共4页

基　　金：湖北省自然科学基金资助项目 ( 99J0 10 4)

摘　　要：用限制性核酸内切酶对鸡毒霉形体 (MG) HS株基因文库中经初步估测可能含有的 4个鸡毒霉形体粘附蛋白(protein of Mycoplasma gallisepticumadhesin,p MGA)基因的 Mg W1 7重组质粒进行了不同组合的酶消化 ,根据消化片段的大小及酶切位点绘制了 7.5 kb外源片段的物理图谱 ;然后根据所得的物理图谱 ,选用 Pst 和 Eco R 将Mg W1 7外源片段酶解成 1 .3、2 .0、4 .2 kb3个部分 ,将它们分别亚克隆到 SK( + ) 质粒上 ,得到了 3个亚克隆子SGp1 0 0、SGp2 0 0、SGp30 0。使用核酸外切酶 缺失法构建缺失子系列 ,经序列分析后得到 Mg W1 7外源片段的全部序列。序列全长 74 34bp,中间含有 2个完整的 p MGA基因和另 2个不完整的 p MGA基因的首部和尾部 ,分别将它们顺次命名为 H- p MGA1 .1、H- p MGA1 .2、H- p MGA1 .3和 H- p MGA1 .4。 2个完整的 p MGA基因的阅读框长度分别为1 96 7bp(1 .2 )和 2 0 39bp(1 .3) ;H- p MGA1 .1首部不完整的阅读框的长度为 72 0 bp,尾部不完整的 H- p MGA1 .4的长度为 1 75 2 bp。将 H- p MGA基因与已报道的 MG.S6株、F株的 p MGA基因进行了比较 ,探讨了 p MGA基因在不同MG菌株中的相似性、基因启动子结构的差异、间隔区内MgW17 recombinant plasmid containing four pMGA genes from (MG) HS gene library was cleaved by different grouped restriction endonuclease.A physical map of the 7 5 kb inserted DNA was constructed according to the size of digesting fragments.MgW17 inserted DNA was digested into three segments(1 3 kb,2 0 kb and 4 2 kb),and sub cloned to SK (+) plasmid which named for SGp100,SGp200 and SGp300 respectively.ExoⅢ was used to construct a set of deletion plasmid of SGp200 and SGp300.The whole sequence of MgW17 inserted DNA was obtained after sequence analysis.The results showed that the size of fragment is 7 434 bp,containing two intact pMGA gene in the midst and two fragmentary pMGA gene in the head and tail.They were named for H pMGA1 1,H pMGA1 2,H pMGA1 3,and H pMGA1 4 sequentially.The open reading frame(ORF) of the H pMGA 1 2 and the H pMGA 1 3 are 1 968 bp and 2 040 bp.The fragmentary ORF of H pMGA 1 1 and H pMGA 1 4 is 720 bp and 1 750 bp.In this article,we compared the H pMGA gene with that of the other MG strains including S6 and F which had been reported previously.We discussed the similarity of the pMGA gene in different MG strains,the property as membrane protein coded by pMGA gene,the structure of promoter and the affection to the transcriptional control of the repeat sequence of GAA in the interval region.

关 键 词：鸡毒霉形体 HS株 pMGA多基因族 序列分析 

分 类 号：S852.62[农业科学—基础兽医学]