摘要
目的研究广州地区新生儿感染人巨细胞病毒（HCMV）临床低传代分离株UL138基因序列特征与多态性。方法从10例被证实为临床HCMV感染的新生儿尿液标本中分离HCMV低传代临床病毒株，进行多重PCR鉴定。对临床分离株进行HCMVUL138基因扩增、克隆、鉴定、测序及呈报GenBank；同时在GenBank搜索HCMVUL138同源序列，行序列分析，应用生物信息学在线软件分析UL138基因翻译后修饰位点、二级结构及等电点。结果成功分离3株HCMV临床病毒株，分别命名为HCMVD3、D2和D52。克隆测序后呈报GenBank并被收录。收录序列号分别为：DQ180375、DQ180387和DQ180359。分析结果显示在HCMV临床低传代D3、D2和D52病毒株UL138基因全序列841个碱基中，存在16个位点变异，可能编码的蛋白质氨基酸残基总数为169个，其基因序列高度保守，核苷酸变异均为碱基替换，无插入或缺失，碱基替换导致了7处氨基酸的改变。HCMVUL138蛋白翻译后修饰位点在除Toledo株外的所有分离株中均高度保守；所有分离株UL138蛋白的预测等电点均为6．51。结论广州地区感染婴儿的HCMVUL138基因及其编码的氨基酸序列极为保守，但仍具有一定的多态性，这在HCMV临床感染与致病机制研究中具有重要意义。
Objective To analyze the nucleotide sequences and genetic polymorphisms of UL138 gene of low passage human cytomegalovirus （HCMV） strains isolated from infants in Guangzhou province. Methods The low passage strains of HCMV were isolated from urine samples of 10 infants with HCMV in- fection in Guangzhou province and identified by multiplex PCR. The UL138 genes were amplified, cloned and identified with sequencing. The sequences were analyzed together with the homologous sequences of 10 clinical isolates published in GenBank. The sequences of UL138 genes were analyzed by using bioinformatics soflwares for investigation of the post-translational modification sites, isoelectric points and second structures of UL138 proteins. Results Three low passage strains of HCMV （ D2, D3 and D52） were isolated from in- fants with congenital HCMV infection, The complete sequences of UL138 genes of the three strains were sub- mitted to GenBank after sequencing identification with the GcnBank accession numbers of DQ180375, DQ180387 and DQ180359, respectively. The UL138 gene sequences of the three clinical isolates were high- ly conservative. Among the 841 base pairs of the UL138 gene sequences, mutations were identified in 16 sites with base substitution, no any insertion and deletion mutation was found. The 16 mutations resulted in 7 amino acid changes. No additional or deleted sites were found with regard to the post translational modifi- cation sites of UL138 protein in all clinical isolates except the Toledo strain. The isoelectric point of UL138 protein was 6.51 for all clinical isolates. Conclusion The UL138 genes and the deduced amino acid se- quences of HCMV strains isolated from infants in Guangzhou were highly conservative, regardless of the poly- morphism of UL138 gene. This study paved the way for further investigation on HCMV infection and its path- ogenic mechanism.
出处
《中华微生物学和免疫学杂志》
CAS
CSCD
北大核心
2015年第6期407-413,共7页
Chinese Journal of Microbiology and Immunology
基金
国家自然科学基金（81070516）
