Secretion Signal and Protein Targeting in Bacteria: a Biological Puzzle

Abstract

Protein targeting in bacterial cells should be a rather simple process, since few subcellular compartments exist compared to eukaryotic cells, where targeting to the nucleus, mitochondria, peroxisomes, endoplasmic reticulum, or chloroplasts is required. In most cases of bacterial protein targeting, the idea is that a tag is contained within the protein, and this label gives the cell information about where the protein should be delivered. This is reminiscent of the tagging of your luggage at the airport to have it delivered where appropriate.