[Construction of the human cytomegalovirus B gene clone and its restriction site analysis by computer].

We constructed two clones of the human cytomegalovirus strain AD169, using the plasmid pBR322 and the recipient bacterium Escherichia coli strain HB101. The human cytomegalovirus B gene was isolated from the recombinant plasmid pAT153 that contained the 20.7-kb Hind III F fragment of the human cytomegalovirus genome. The recombinant plasmid pAT153 was digested with BamHI and a 8.5-kb fragment was isolated and ligated with BamHI-digested pBR322 to form the recombinant plasmid pB1. pB1 was further digested with BamHI-Hind III and a 5.1-kb fragment was isolated, and ligated with BamHI-Hind III digested pBR322 to form the recombinant plasmid pBH1. The human cytomegalovirus B gene sequence was analysed by Beckman Microgenie Systems. The results indicated that the human cytomegalovirus B gene could be further digested by 13 kinds of restrict endonucleases. The size of the restrict fragments was between 22 base pairs to 2.9 kilobase pairs. The construction of the expression plasmid that contained human cytomegalovirus B gene is now in progress.