Juxtaposition of signal-peptide charge and core region hydrophobicity is critical for functional signal peptides

• Published in: Archives of microbiology 2002-10, Vol.178 (4), p.306-310
• Main Authors: RUSCH, Sharyn L, MASCOLO, Cynthia L, KEBIR, Maha O, KENDALL, Debra A
• Format: Article
• Language: English
• Subjects: Adenosine Triphosphatases - genetics; Adenosine Triphosphatases - metabolism; Alkaline Phosphatase - metabolism; Amino Acid Sequence; Bacterial Proteins; Bacteriology; Biological and medical sciences; Escherichia coli - chemistry; Escherichia coli - genetics; Escherichia coli - metabolism; Escherichia coli Proteins - genetics; Escherichia coli Proteins - metabolism; Fundamental and applied biological sciences. Psychology; Genetics; Hydrophobic and Hydrophilic Interactions; Membrane Transport Proteins - genetics; Membrane Transport Proteins - metabolism; Microbiology; Molecular Sequence Data; Mutation; Permeability, membrane transport, intracellular transport; Protein Precursors - metabolism; Protein Sorting Signals - genetics; Protein Sorting Signals - physiology; Protein Transport; SEC Translocation Channels
• ISSN: 0302-8933; 1432-072X
• DOI: 10.1007/s00203-002-0453-z

In Escherichia coli, exported proteins are synthesized as precursors containing an amino-terminal signal peptide which directs transport through the translocase to the proper destination. We have constructed a series of signal peptide mutants, incorporating linker sequences of varying lengths between the amino-terminal charge and core region hydrophobicity, to examine the requirement for the juxtaposition of these two structural features in promoting protein transport. In vivo and in vitro analyses indicated that high transport efficiency via signal peptides with core regions of marginal hydrophobicity absolutely requires the proximity of sufficient charge.