Cover Picture: Design, Synthesis and Characterization of a New Anionic Cell-Penetrating Peptide: SAP(E) (ChemBioChem 6/2011)

Authors

  • Irene Martín,

    1. Institute for Research in Biomedicine (IRB Barcelona), Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona (Spain), Fax: (+34) 93-4037126
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  • Dr. Meritxell Teixidó,

    Corresponding author
    1. Institute for Research in Biomedicine (IRB Barcelona), Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona (Spain), Fax: (+34) 93-4037126
    • Institute for Research in Biomedicine (IRB Barcelona), Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona (Spain), Fax: (+34) 93-4037126
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  • Prof. Dr. Ernest Giralt 

    Corresponding author
    1. Institute for Research in Biomedicine (IRB Barcelona), Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona (Spain), Fax: (+34) 93-4037126
    2. Department of Organic Chemistry, University of Barcelona, Martí i Franquès 1–11, 08028 Barcelona (Spain)
    • Institute for Research in Biomedicine (IRB Barcelona), Barcelona Science Park, Baldiri Reixac 10, 08028 Barcelona (Spain), Fax: (+34) 93-4037126
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Abstract

original image

The cover picture shows a rocket representing the anionic cell-penetrating peptide (CPP) SAP(E) reported by E. Giralt, M. Teixidó and I. Martín on p. 896 ff. The “moon” is a confocal microscopy image of HeLa cells after 3 hours of coincubation with CF-SAP and Rd-SAP(E). To the best of our knowledge, SAP(E) is one of the first anionic CPPs to be described. It adopts a polyproline II secondary structure in aqueous buffer and self-assembles to form aggregated structures able to internalize different cell lines with almost no toxic effects. The internalization mechanism proposed for SAP(E) is clathrin-independent. Much can be achieved from a negatively charged CPP, for example, the spectrum of possible cargoes increases enormously. Positively charged cargoes could now be added to the list of molecules with the capacity to be delivered by these promising vectors. Illustration made with the valuable help of José Alberto Santos.

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