esis ▁of ▁the ▁pe pt ide ▁ch ains . ▁Where as ▁in ▁the ▁SR P ▁path way , ▁Y id C ▁is ▁the ▁ch aper one , ▁and ▁transport ▁prote ins ▁to ▁the ▁cell ▁memb rane ▁while ▁they ▁are ▁still ▁under going ▁pe pt ide ▁synth esis . ▁ ▁Sec A ▁or ▁post - trans l ational ▁path way ▁ ▁Prote ins ▁are ▁synth es ised ▁in ▁rib os om es ▁by ▁a ▁process ▁of ▁serial ly ▁adding ▁am ino ▁ac ids , ▁called ▁translation . ▁In ▁Sec A ▁path way , ▁a ▁ch aper one ▁trigger ▁factor ▁( TF ) ▁first ▁bind ▁to ▁the ▁exposed ▁N - term inal ▁signal ▁sequence ▁of ▁the ▁pe pt ide ▁chain . ▁As ▁el ong ation ▁of ▁pe pt ide ▁chain ▁continues , ▁T F ▁is ▁replaced ▁by ▁Sec B . ▁Sec B ▁specifically ▁maintain s ▁the ▁pe pt ide ▁in ▁an ▁unfold ed ▁state , ▁and ▁a ids ▁in ▁the ▁binding ▁of ▁Sec A . ▁The ▁complex ▁can ▁then ▁bind ▁to ▁Sec Y EG , ▁by ▁which ▁Sec A ▁is ▁activ ated ▁by ▁binding ▁with ▁ATP . ▁D ri ven ▁by ▁ATP ▁energy , ▁Sec A ▁push es ▁the ▁protein ▁through ▁the ▁sec Y EG ▁channel . ▁Sec D / F ▁complex ▁also ▁helps ▁in ▁the ▁pulling ▁of ▁the ▁protein ▁from ▁the ▁other ▁side ▁of ▁the ▁cell ▁memb rane . ▁ ▁SR P ▁path way ▁ ▁In ▁this ▁path way , ▁SR P ▁compet es ▁with ▁T F ▁and ▁bind s ▁to ▁the ▁N -