摘要
在双生病毒DNA中存在保守序列5′TAATATTAC3′,推测也存在于印度木薯花叶双生病毒(ICMV)基因组中。以此序列的互补链为引物,合成 ICMV cDNA,cDNA 的主带大小为2.7kb。测定了外壳蛋白的基因序列共768个核苷酸,并分析了外壳蛋白的一级结构。ICMV 外壳蛋白由20种氨基酸的256个残基组成,其中脂肪族氨基酸含量高,碱性氨基酸含量高于酸性氨基酸,含硫氨基酸和亚氨基酸的含量较低。比较 ICMV 与7种木薯粉虱(Bemi-ria tabaci)传播的双生病毒外壳蛋白,其 N-末端变异程度大,而 C-末端基本恒定,中部存在3段较长的保守序列。
Geminivirus genomes have a conserved nine nucleotide sequence(5'TAATATTAC 3')thatwas hypothesised to exist in ICMV.Assuming this hypothesis to be correct,cDNA was syn-thesized by utilizing the complementary sequence as a primer(5'GTAATATTA 3')and themain product was about 2.7kb.cDNA molecules were cut with EcoRl,cloned in vector pUC19which was used to transform DH5α competent cells.By colony hybridization,thirty-nine re-combinant plasmids were found.The sizes of inserts rangetl from 0.15 kb to 2.5kb as shownby EcoRl analysis.Coat protein gene was sequenced and translated into amino acid sequencesby UWGCG software.Coat protein consisted of 256 residues belonging to 20 species of ami-no acids.Direct comparison of the coat protein of ICMV with that of seven other whitefly-transmitted geminiviruses showed that the amino acid sequences of the N-terminal regions ten-ded to be different,but the parts at the C-terminal were very similar.
出处
《微生物学报》
CAS
CSCD
北大核心
1993年第2期98-103,共6页
Acta Microbiologica Sinica
关键词
外壳蛋白
木薯
双生病毒
结构
Indian cassava mosaic geminivirus
Coat protein
DNA sequence
