Identified scFv antibody sequences. Peptide sequences are reported in single-letter code. Amino acids in the mutated clones identical to parental MA39 are represented by a dash. CP1 – B18 and E1 – E16 groups of clones were isolated from first and second maturation libraries, respectively. Letters "q" and "t" correspond to glutamine and tryptophan amino acids in suppressed nonsense codons.