title: Juxtaposition of signal-peptide charge and core region hydrophobicity is critical for functional signal peptides.
abstract: 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.
authors.affiliation: Department of Molecular and Cell Biology, University of Connecticut, 75 North Eagleville Road, Storrs, CT 06269-3044, USA.
authors.forename: Sharyn L
authors.initials: SL
authors.lastname: Rusch
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Mascolo
authors.forename: Maha O
authors.initials: MO
authors.lastname: Kebir
authors.forename: Debra A
authors.initials: DA
authors.lastname: Kendall
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D004926:Escherichia coli / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism; D057927:Hydrophobic and Hydrophilic Interactions; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D011498:Protein Precursors / Q000378:metabolism; D021382:Protein Sorting Signals / Q000235:genetics / Q000502:physiology*; D021381:Protein Transport; D000069816:SEC Translocation Channels; D000081416:SecA Proteins
chemical_list: D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; D011498:Protein Precursors; D021382:Protein Sorting Signals; D000069816:SEC Translocation Channels; D000469:Alkaline Phosphatase; D000251:Adenosine Triphosphatases; D000081416:SecA Proteins