TABLE 1.

Amino acid residues at positions 120 and 121 in PIB proteins from strains isolated from transformation of FA19 penA4 mtr (PIB) with porIB DNA harboring randomized codon mutations at these positions

No. of clonesAmino acid 120Amino acid 121
2KF
4KH
1KM
3KN
4KR
2KT
2KY
1RH
1PP