African swine fever virus trans-prenyltransferase
African swine fever virus trans-prenyltransferase
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DOI：
10.1074/jbc.272.14.9417
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发表时间：
1997-04-04
影响因子：
4.8
通讯作者：
Salas, ML
中科院分区：
文献类型：
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作者：
Alejo, A;Yanez, RJ;Salas, ML
本研究描述了一种与戊烯基转移酶同源的非洲猪瘟病毒基因的特征。该基因被命名为B318L，位于病毒基因组中心区域的EcoRI B片段内，编码一个预计分子量为35,904的多肽。该蛋白的特点是在氨基端存在一个假定的疏水跨膜结构域。该基因在病毒感染后期表达，转录开始于相对于翻译起始密码子第一个核苷酸的-118、-119、-120和-122位点。B318L蛋白具有香叶基二磷酸合酶、法尼基二磷酸合酶和其他戊烯基转移酶所特有的四个高度保守区域和两个富含天冬氨酸的基序共线排列。在这些区域中，B318L蛋白与各种丙烯基转移酶的同源率在28.6% ~ 48.7%之间。将该基因克隆到不含氨基末端疏水区的载体pTrxFus中，并在大肠杆菌中表达。重组蛋白经亲和层析纯化基本达到均匀性，可催化不同烯丙基二磷酸异戊烯基的顺序缩合，其中二磷酸法尼酯是该反应的最佳烯丙基底物。合成了含有3-13个异戊二烯单元的全反式聚戊烯基二磷酸酯，鉴定出B318L蛋白为反式戊烯基转移酶。
The present study describes the characterization of an African swine fever virus gene homologous to prenyltransferases. The gene, designated B318L, is located within the EcoRI B fragment in the central region of the virus genome, and encodes a polypeptide with a predicted molecular weight of 35,904. The protein is characterized by the presence of a putative hydrophobic transmembrane domain at the amino end. The gene is expressed at the late stage of virus infection, and transcription is initiated at positions -118, -119, -120, and -122 relative to the first nucleotide of the translation start codon. Protein B318L presents a colinear arrangement of the four highly conserved regions and the two aspartate-rich motifs characteristic of geranylgeranyl diphosphate synthases, farnesyl diphosphate synthases, and other prenyltransferases. Throughout these regions, the percentages of identity between protein B318L and various prenyltransferases range from 28.6 to 48.7%. The gene was cloned in vector pTrxFus without the amino-terminal hydrophobic region and expressed in Escherichia coli. The recombinant protein, purified essentially to homogeneity by affinity chromatography, catalyzes the sequential condensation of isopentenyl diphosphate with different allylic diphosphates, farnesyl diphosphate being the best allylic substrate of the reaction. All-trans-polyprenyl diphosphates containing 3-13 isoprene units are synthesized, which identifies the B318L protein as a trans-prenyltransferase.