Chapter 13.8, Problem 2CC

Summary Introduction

A process by which a polypeptide chain folds to form an active protein is known as protein folding. The structure of a protein is very critical for its function. A process by which a protein molecules move between cellular compartments is known as protein translocation. The translocation process advances the mRNA-tRNA moiety on the ribosome, in order to permit the next codon to enter into the decoding center. There are two translocation systems such as Sec system and Tat system and two secretion systems, such as Type I and Type IV are present in both Gram-positive bacteria and Gram-negative bacteria.

The translocation or secretion system that is most widespread of all the translocation system is the Sec system. The Sec system is occasionally termed as the general secretion pathway. This is because, it is highly conserved and have been identified in all three domains of life, such as eukaryotes, bacteria, and archaea. The Sec system translocates unfolded proteins across the plasma membrane or incorporates the unfolded proteins in the plasma membrane itself.