kcat enzyme substrate Km kcat enzyme substrate Km substrate IIa 0.556 IIa_alpha2M compartment_1 HenriMichaelisMenten_irreversible_kcat kcat_X RVV X km_X compartment_1 ki_Xa Xa compartment_1 k_PT Va Xa PL k_PL PT compartment_1 HenriMichaelisMenten_irreversible_kcat kcat_V IIa V km_V compartment_1 HenriMichaelisMenten_irreversible_kcat kcat_II PT II km_II compartment_1 HenriMichaelisMenten_irreversible_kcat kcat_2 Xa II km_2 compartment_1 ki_IIaAlpha2M IIa compartment_1 ki_IIaATIII IIa