Site-directed PEGylation of A2 domain residues and effect on prothrombin processing. (A) Cartoon representation of full-length pseutarin C, colored as in Figure 2, indicating the positions of mutated and PEGylated residues on the A2 domain, shown as blue balls. (B) Effects of both Cys mutation (red circle) and PEGylation (blue square) on thrombin generation were tested by the chromogenic assay. mAu, milli–absorbance unit.