USA As Represented by Secretary of the Navy

The Scripps Research Institute

University of Chicago

Sanford Burnham Prebys Medical Discovery Institute

Philip E Dawson

Igor L Medintz

James B Delehanty

Jeffrey R Deschamps

Hedi M Mattoussi

Stephen B H Kent

Kimihiro Susumu

Tom W Muir

Michael H Stewart

Kelly Boeneman

Juan Bautista Blanco-Canosa

Glyn Dawson

Alan L Huston

Eunkeu Oh

Alexander L Efros

Okhil Nag

Lauren D Field

Richard A Lerner

Lynne Canne Bannen

Stephen B Kent

Elena B Pasquale

Steven J Bark

Jia Xie

Hongkai Zhang

Harry Tetsuo Uyeda

Joyce A Breger

Parag Chitnis

Nashaat Rasheed

Markus Muttenthaler

Stefan J Riedl

Ryan Walters

Erika Olson

Johanna Scheinost

Emmanuel Sturchler

Michael C Fitzgerald

Patricia McDonald

John R Cressman

A construct for detecting cellular membrane potential includes a nanoparticle operable as an electron donor; a modular peptide attached to the nanoparticle, the peptide comprising a nanoparticle association domain, a motif configured to mediate peptide insertion into the plasma membrane, and at least one attachment point for an electron acceptor positioned at a controlled distance from the nanoparticle; and an electron acceptor. The nanoparticle can be a quantum dot and the electron acceptor can be Cfullerene. Emission correlates with cellular membrane potential.

Modular, multifunctional nanoparticle-based bioconjugate for realtime visualization of cellular membrane potential

A construct for detecting cellular membrane potential includes a nanoparticle operable as an electron donor; a modular peptide attached to the nanoparticle, the peptide comprising a nanoparticle association domain, a motif configured to mediate peptide insertion into the plasma membrane, and at least one attachment point for an electron acceptor positioned at a controlled distance from the nanoparticle; and an electron acceptor. The nanoparticle can be a quantum dot and the electron acceptor can be Cfullerene. Photoacoustic emission from the construct correlates with cellular membrane potential.

Multifunctional nanoparticle bioconjugates for photoacoustic-based recording of cellular membrane potential

The invention provides combinatorial peptide or polypeptide libraries that can become membrane tethered once expressed in cells. The invention additionally provides methods for selecting peptide modulators (e.g., agonists) of GPCRs from the combinatorial libraries of the invention. The invention also provides novel GPCR polypeptide modulators, e.g., biased polypeptide agonists of the glucagon-like peptide 1 receptor (GLP-1R). The invention further provides methods of promoting insulin sensitivity, lowering blood glucose, and reducing body weight as well as methods for treating various diseases such as diabetes and obesity.

Methods and compositions related to GPCR agonist polypeptides

The present specification discloses APY cyclic peptides having EphA4 antagonistic activity, pharmaceutical compositions containing such EphA4 antagonists, and methods and uses of treating an EphA4-based disease, disorder or pathology in an individual using such APY cyclic peptides or pharmaceutical compositions.

EPHA4 cyclic peptide antagonists for neuroprotection and neural repair

Nanoparticles (and optionally a cargo such as a drug) can be delivered to cells by attaching just a single dendritic peptide to the nanoparticle. The dendritic peptide includes a polyhisitidine motif and a hinge and a spacer connecting the polyhistidine to a lysine-based dendritic wedge displaying at least two copies of a cell-penetrating peptide motif.

Use of single dendritic wedge cell penetrating peptides to facilitate cellular delivery of nanoparticles and nanoparticles carrying cargos

A peptide attached to a nanoparticles (such as quantum dots) selectively directs the nanoparticles to neurons in a tissue or organism.

Delivery of nanoparticles to neurons

A peptide directs nanoparticles (such as quantum dots) to the plasma membrane of mammalian cells. A method of delivery of a nanoparticle to a plasma membrane of a cell includes providing to the cell a nanoparticle attached to a peptide configured to direct the nanoparticle the plasma membrane, and allowing the cell to take up the nanoparticle. The nanoparticle can be a FRET donor to an organic dye.

Modular functional peptides for delivery of nanoparticles

Described are nucleic acids encoding a polypeptide for delivery of a nanoparticle to the cytosol, the peptide comprising: (a) a nanoparticle association domain, (b) a spacer domain, (c) an uptake domain, and (d) a vesicle escape domain, wherein the domains (a) through (d) appear in the same order as listed above, and wherein the peptide, upon addition of a non-hydrolyzable lipophilic moiety to the vesicle escape domain and binding to a nanoparticle, is effective to induce uptake of a nanoparticle by a cell and delivery of the nanoparticle to the cytosol of the cell. Also described are methods of delivery of a nanoparticle to the cytosol of a cell, the method comprising providing to a cell a nanoparticle attached to such a peptide. Exemplary nanoparticles include quantum dots.

Modular functional peptides for the intracellular delivery of nanoparticles

Described are peptides for delivery of a nanoparticle to the cytosol, the peptide comprising: (a) a nanoparticle association domain; (b) a proline-rich spacer domain; (c) an uptake domain; and (d) a vesicle escape domain comprising a non-hydrolyzable lipid moiety, wherein the spacer domain is between the nanoparticle association domain and the uptake and vesicle escape domains, and wherein the peptide, when attached to an extracellular nanoparticle, is effective to induce uptake of the nanoparticle by a cell and delivery of the nanoparticle to the cytosol of the cell. Also described are methods of delivery of a nanoparticle to the cytosol of a cell, the method comprising providing to a cell a nanoparticle attached to such a peptide. Exemplary nanoparticles include quantum dots.

A method for covalent attachment of peptides to luminescent quantum dots or other inorganic nanoparticles. The first step in the method involves functionalizing at least a portion of a surface of the quantum dot or nanoparticle with one or more materials having at least one reactive functional group therein. Subsequently, a peptide having a reactive functional group is reacted with at least some of the quantum dot or nanoparticle reactive functional groups to covalently bond at least some of the peptide to the quantum dots or nanoparticles. Modifications of the basic method are disclosed which provide methods allowing customized fabrication of quantum dots having a variety of different functional properties and combinations of functional properties. Also disclosed are quantum dots and nanoparticles made by the methods of the present invention.

Covalent attachment of peptides and biological molecules to luminescent semiconductor nanocrystals

Proteins of moderate size having native peptide backbones are produced by a method of native chemical ligation. Native chemical ligation employs a chemoselective reaction of two unprotected peptide segments to produce a transient thioester-linked intermediate. The transient thioester-linked intermediate then spontaneously undergoes a rearrangement to provide the full length ligation product having a native peptide bond at the ligation site. Full length ligation products are chemically identical to proteins produced by cell free synthesis. Full length ligation products may be refolded and/or oxidized, as allowed, to form native disulfide-containing protein molecules. The technique of native chemical ligation is employable for chemically synthesizing full length proteins.

Synthesis of proteins by native chemical ligation

A protein signature analysis is obtained using a peptide ladder library. The molecular signature of a protein is defined to be that subsequence of amino acid positions within the protein which are essential for the protein to bind to a target molecule. The molecular signature may be determined by screening a peptide ladder library which corresponds to the protein against the target molecule. The peptide ladder library is a library of m peptides wherein each peptide has an amino acid sequence of length m corresponding to an amino acid sequence of the protein, with one exception, viz. peptide has a substitute amino acid at position and the substitute amino acid is attached by a labile bond to its neighboring amino acid. Screening the peptide ladder library against the target molecule results in a division of the original mixture into a positive (functional) pool and a negative (non-functional) pool. The pools are separated and subjected to cleavage to obtain cleavage products. Analysis of cleavage products by mass spectrometry identifies the positions that are essential for the protein to bind to its molecular target.

Process for characterizing proteins

Disclosed herein is a process whereby oligopeptides are ligated to form ligation peptide products. In the first step, two starting oligopeptides are ligated to form an intermediate having an amino-thioester linkage. In the second step, the aminothioester linkage undergoes a rearrangement to form a peptide having an N-substituted amide linkage. In an optional third step, the N-substitution of the amide linkage is chemically removed to form a native peptide linkage.

General chemical ligation

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San Diego, CA, United States of America

Philip E Dawson