Apocytochrome b 5 (apocyt b 5), a small b-type cytochrome with heme prosthetic group removal, has been subjected to steered molecular dynamics (SMD) simulations for investigating the consequences of mechanical force-induced unfolding. Both constant velocity (0.5 and 1.0 Å/ps) and constant force (500, 750 and 1000 pN) stretching have been employed to model forced unfolding of apocyt b 5. The results of SMD simulations elucidate that apocyt b 5 is protected against external stress mainly through the interstrand hydrogen bonding between its β1–...
