Essential component of the PAM complex, a complex required for the translocation of transit peptide-containing proteins from the inner membrane into the mitochondrial matrix in an ATP-dependent manner. Seems to control the nucleotide-dependent binding of SSC1 to substrate proteins and the association of SSC1 with TIM44. Component of the PAM complex, at least composed of SSC1 (mtHsp70), MGE1, TIM44, PAM16/TIM16, PAM17 and PAM18/TIM14. Interacts with SSQ1. The N-terminus is blocked. Belongs to the GrpE family.