Difference between revisions of "Part:BBa K208005"

Latest revision as of 16:45, 22 October 2009

TorA Signal Peptide - Silver Fusion Compatible

This is a Silver-fusion compatible BioBrick part that can be attached to other proteins to target those proteins for export out of the cytoplasm. The TorA sequence targets folded proteins to the Tat-dependent pathway of Type II secretion.

Usage and Biology

The TorA signal peptide has been used by multiple researchers to export folded GFP into the periplasm of cells (Barrett, 2003; Santini, 2001; Thomas, 2001). It can be fused to non-exportable proteins as a tag for translocation out of the periplasm by the Tat-dependent system.

The Twin-arginine-translcocation system is used to export folded proteins into the periplasmic space (Choi, 2004). Like the Sec-dependent pathways, specific N-terminal signal peptide sequences target a protein for export by the TAT machinery. Although similar, TAT signal peptides differ from those that target proteins to the Sec machinery. TAT signal peptides contain a conserved sequence of seven amino acids, (S/T)-R-R-x-F-L-K, at the interface between the N- and H-regions, where x represents a polar amino acid (Berks, 2000; Palmer, 2004). The twin-arginine residues are consistently present in TAT signal peptides, and the occurrence of the other amino acids is greater than 50% (Berks 1996, Berks 2000, Palmer, 2004). The qualities, such as hydrophobicity, affect the secretion mechanism for which it targets. Sequence and Features