FIG 2.

Creation of chimeric SV41 HN proteins. (A) Schematic diagram. Positions of the epitopes for the SV41 HN-specific MAb (127A-1) and HPIV2 HN-specific MAb (173-1A) are indicated. The previously reported chimeric HN protein CH95-571 was renamed SCA after the restriction enzyme ScaI, which had been utilized for the chimeric recombination (10). Filled circles below the diagrams of SCA and SCA-RII indicate the positions of EcoRI sites in the cDNA encoding these chimeric proteins. (B) Primary structures of 20 intermediates between SCA-RII and SCA. The residue numbers of 13 amino acids of region II that are not conserved between SCA-RII and SCA (that is, between the SV41 HN protein and the HPIV2 HN protein) are denoted. The primary structure of each intermediate is represented by a combination of these 13 amino acids: black boxes indicate amino acids characteristic of SCA-RII, while gray boxes indicate those characteristic of SCA.