Recombinant BβArg448 and BβLys448 fibrinogen, permeation, and polymerization curves of fibrin formed from the 2 variants. (A) Recombinant fibrinogen resolved on 12% to 24% SDS-PAGE: lane 1 Lys448, lane 2 Arg448. (B) Mean turbidity curves (± SEM) of 4 experiments with each Arg448 and Lys448 fibrin variants at fibrinogen concentration of 1.3 μM, 2.5 mmol CaCl2, and 0.5 U/mL thrombin. The final maximum absorbency at 350 nm was lower in the less common variant Lys448 than in the more common Arg448, indicating the presence of thinner fibers in Lys448 fibrin clots. (C) Mean turbidity curves (± SEM) of 4 experiments with each Arg448 and Lys448 fibrin variants after addition to fibrinogen-depleted plasma (1 volume of plasma was added to 3 volumes of recombinant fibrinogen at 1.3 μM concentration), 2.5 mmol CaCl2, and 0.5 U/mL thrombin.
