Archaeal Sec-Dependent Protein Translocation

University Of Pennsylvania, Philadelphia PA

Investigators

Abstract

Protein transport across hydrophobic membranes is an essential cellular process in all organisms. However, the way in which this process occurs remains largely uncharacterized. Understanding the mechanism of this transport in the archaea, organisms which comprise one of the three domains of life and are proposed to be the closest ancestors of the eukaryotes (animals and plants, among others), may be key in resolving some of the pertinent issues, such as the identification of 1) the mechanisms by which proteins are directed to the membrane, and 2) the energy sources required for protein translocation. Thus, using biochemical and molecular biological tools, researchers seek a better understanding of the protein translocation mechanism of an archaeon that is amenable to these studies. An exploration of the biology of protein transport in the archaea, organisms in which this process is still poorly understood, will shed light on novel processes by which proteins cross archaeal membranes. However, it will also provide new insights into previously-identified bacterial and eukaryotic protein translocation mechanisms. For example, in eukaryotes, secreted antibodies are essential for the defense against pathogens, while some prokaryotes secrete toxins, which are central to their pathogenicity. Thus, the understanding gained through these studies may allow us to modulate the secretion of pathogenic compounds, as well as optimize defense mechanisms against them. Additionally, this research has implications for advancements in biotechnology. Many microorganisms secrete enzymes to scavenge extracellular molecules. A significant number of these enzymes are extremely useful in many industrial settings, including chemical, pharmaceutical, and agricultural industries. Thus, understanding protein export mechanisms will help in the large-scale production of recombinant secreted proteins of interest in the industrial sector.