played an important role in virus particle assembly and infectivity. Thus, the pI value of the recombinant CP constructs was adjusted to more closely resemble the wild-type CP pI value by inserting the acidic amino acid (glutamate) to the 3 end of CP ( Table 2 ). The experiments (Table 1) , however, showed that although the pI was still higher than that of the wild type (Table 2) , the construct pCG+FSRTRE remained infectious. This implies that infectivity of the clones was not directly related to the deviation in pI value with the wild-type virus CGMMV CP.