[Cloning and expression of the 3C-proteinase gene from the poliomyelitis virus in E. coli cells]

Expression of the 3C protease gene of poliovirus type 1 (Mahoney) in E. coli cells using various vectors was studied. The 3C gene was shown to be expressed effectively upon its cloning in HindII/HindII (bases 5240 to 6770) and in HindII/HindIII (bases 5240 to 6056) fragments of poliovirus cDNA in pTTQ8 vector containing tac-promoter and lacI-repressor gene. Products of processing at the N-terminal 3C protease Gln-Gly site and polypeptides formed upon translation from an alternative methionine, which was coded by bases 5516-5518 of poliovirus cDNA, were found among virus-specific proteins. Processing at the C-terminal 3C protease Gln-Gly site was not observed.