term inal ▁signal ▁sequence . ▁Prote ins ▁from ▁inner ▁memb rane ▁stops ▁the ▁process ▁of ▁chain ▁el ong ation . ▁The ▁SR P ▁then ▁bind s ▁to ▁a ▁memb rane ▁re ceptor , ▁F ts Y . ▁The ▁pe pt ide ▁chain - SR P - F ts Y ▁complex ▁is ▁then ▁transport ed ▁to ▁Seg Y , ▁where ▁pe pt ide ▁el ong ation ▁res umes . ▁ ▁Tat ▁system ▁ ▁The ▁tw in ▁arg in ine ▁trans location ▁( T at ) ▁system ▁is ▁similar ▁to ▁Sec ▁in ▁the ▁process ▁of ▁protein ▁secret ion , ▁however , ▁it ▁sends ▁prote ins ▁only ▁in ▁their ▁fol ded ▁( ter ti ary ) ▁state . ▁It ▁is ▁used ▁by ▁all ▁types ▁of ▁b acter ia , ▁as ▁well ▁as ▁arch ae a , ▁and ▁ch lor op last s ▁and ▁mit och ond ria ▁of ▁plants . ▁In ▁b acter ia , ▁the ▁Tat ▁system ▁exports ▁prote ins ▁from ▁the ▁cy top las m ▁across ▁the ▁inner ▁cell ▁memb rane ; ▁whereas ▁in ▁ch lor op last s , ▁it ▁is ▁present ▁in ▁the ▁thy la ko id ▁memb rane ▁where ▁it ▁a ids ▁the ▁import ▁of ▁prote ins ▁from ▁the ▁st rom a . ▁Tat ▁prote ins ▁are ▁highly ▁variable ▁in ▁different ▁b acter ia ▁and ▁are ▁class ified ▁into ▁three ▁major ▁types , ▁namely ▁Tat A , ▁Tat B , ▁and ▁Tat C . ▁For ▁example , ▁while ▁there ▁are ▁only ▁two ▁functional ▁Tat ▁prote ins ▁in ▁Bac ill us ▁sub