A naturally occurring bacterial Tat signal peptide lacking one of the ‘invariant’ arginine residues of the consensus targeting motif

• Published in: FEBS letters 2001-05, Vol.497 (1), p.45-49
• Main Authors: Hinsley, Andrew P., Stanley, Nicola R., Palmer, Tracy, Berks, Ben C.
• Format: Article
• Language: English
• Subjects: Amino Acid Motifs - physiology; Amino Acid Substitution; Arginine - genetics; Bacterial protein export; Bacterial Proteins - chemistry; Bacterial Proteins - genetics; Bacterial Proteins - metabolism; Consensus Sequence - physiology; Molecular Sequence Data; Mutagenesis, Site-Directed; Oxidoreductases - chemistry; Oxidoreductases - genetics; Oxidoreductases - metabolism; Protein Sorting Signals - physiology; Protein Transport - physiology; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; Rieske protein; Salmonella enterica - enzymology; Sec-independent; Sequence Homology, Amino Acid; Structure-Activity Relationship; Subcellular Fractions - chemistry; Tat pathway; Tetrathionate reductase; Twin–arginine signal peptide
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/S0014-5793(01)02428-0

Currently described substrates of the bacterial Tat protein transport system are directed for export by signal peptides containing a pair of invariant arginine residues. The signal peptide of the TtrB subunit of Salmonella enterica tetrathionate reductase contains a single arginine residue but is nevertheless able to mediate Tat pathway transport. This naturally occurring example of a Tat signal peptide lacking a consensus arginine pair expands the range of sequences that can target a protein to the Tat pathway. The possible implications of this finding for the assembly of electron transfer complexes containing Rieske proteins in plant organelles are discussed.