  Mechanical stretching of the I27 domain of titin and of its double and triple
repeats are studied through molecular dynamics simulations of a Go-like model
with Lennard-Jones contact interactions. We provide a thorough characterization
of the system and correlate the sequencing of the folding and unraveling events
with each other and with the contact order. The roles of cantilever stiffness
and pulling rate are studied. Unraveling of tandem titin structures has a
serial nature. The force-displacement curves in this coarse-grained model are
similar to those obtained through all atom calculations.
