Abstract: Modified proteins are represented by the formula R-L-R′, wherein R and R′ are peptides or pseudopeptides linked to one another by linkage L. Linkage L may be either a thiol ester pseudopeptide backbone linkage or a selenol ester pseudopeptide backbone linkage.

Abstract: Synthetic erythropoiesis stimulating proteins are provided. Also provided are methods for synthesizing the proteins. The invention further relates to derivatives of such synthetic erythropoiesis stimulating proteins that are polymer-modified in a defined manner. Methods and uses for such proteins and derivatized proteins are also provided.

Abstract: The invention is directed to nucleophile-stable thioester generating compounds comprising an orthothioloester or a carboxyester thiol, methods of production and use. The compounds and methods have wide applicability in organic synthesis, including the generation of peptide-, polypeptide- and other polymer-thioesters. The invention is particularly useful for generating activated-thioesters from precursors that are made under conditions in which strong nucleophiles are employed, such as peptides or polypeptides made using Fmoc SPPS, as well as multi-step ligation or conjugation schemes that require (or benefit from the use of) compatible selective approaches for directing a specific ligation or conjugation reaction of interest.

Abstract: Method is described for sequencing polypeptides by forming peptide ladders comprising a series of polypeptides in which adjacent members of the series vary by one amino acid residue and determining the identity and position of each amino acid in the polypeptide by mass spectroscopy.

Abstract: The present invention relates to methods and compositions for lipid matrix-assisted chemical ligation and synthesis of membrane polypeptides that are incorporated in a lipid matrix. The invention is exemplified in production of a prefolded membrane polypeptide embedded within a lipid matrix via stepwise chemoselective chemical ligation of unprotected peptide segments, where at least one peptide segment is embedded in a lipid matrix. Any chemoselective reaction chemistry amenable for ligation of unprotected peptide segments can be employed. Suitable lipid matrices include liposomes, micelles, cell membrane patches and optically isotropic cubic lipidic phase matrices. Prefolded synthetic and semi-synthetic membrane polypeptides synthesized according to the methods and compositions of the invention also permit site-specific incorporation of one or more detectable moieties, such as a chromophore, which can be conveniently introduced during synthesis.

Abstract: 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. peptidem has a substitute amino acid at positionm 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.

Abstract: The present invention provides methods, apparatus and kits for synthesizing assembled peptides and proteins on a solid phase with sequential ligation of three or more unprotected peptide segments using chemoselective and mild ligation chemistries in aqueous solution. Also provided are methods of monitoring solid phase sequential ligation reactions using MALDI or electrospray ionization mass spectrometry of reaction products.

Abstract: Processes for the preparation of modified proteins comprising the coupling of a first peptide segment having a haloacyl group at the N-terminus thereof with a second peptide sequent having a carbonylthiol group at the C-terminus thereof are disclosed. Novel modified proteins produced by the process are also disclosed.

Abstract: The present invention provides methods, apparatus and kits for synthesizing assembled peptides and proteins on a solid phase with sequential ligation of three or more unprotected peptide segments using chemoselective and mild ligation chemistries in aqueous solution. Also provided are methods of monitoring solid phase sequential ligation reactions using MALDI or electrospray ionization mass spectrometry of reaction products.

Abstract: The present invention relates to methods and compositions for lipid matrix-assisted chemical ligation and synthesis of membrane polypeptides that are incorporated in a lipid matrix. The invention is exemplified in production of a prefolded membrane polypeptide embedded within a lipid matrix via stepwise chemoselective chemical ligation of unprotected peptide segments, where at least one peptide segment is embedded in a lipid matrix. Any chemoselective reaction chemistry amenable for ligation of unprotected peptide segments can be employed. Suitable lipid matrices include liposomes, micelles, cell membrane patches and optically isotropic cubic lipidic phase matrices. Prefolded synthetic and semi-synthetic membrane polypeptides synthesized according to the methods and compositions of the invention also permit site-specific incorporation of one or more detectable moieties, such as a chromophore, which can be conveniently introduced during synthesis.

Abstract: Novel proteins and libraries comprising them are disclosed. The proteins comprise one or more functional protein modules from different parent protein molecules. The proteins and libraries are exemplified by the preparation of cross-over chemokines comprising various combinations of peptide segments derived from RANTES, SDF-1 and vMIP-I and vMIP-II. The proteins and libraries are extremely pure and can be provided in non-limiting high yields suitable for diagnostic and high-throughput screening assays.

Abstract: The present invention provides methods, apparatus and kits for synthesizing assembled peptides and proteins on a solid phase with sequential ligation of three or more unprotected peptide segments using chemoselective and mild ligation chemistries in aqueous solution. Also provided are methods of monitoring solid phase sequential ligation reactions using MALDI or electrospray ionization mass spectrometry of reaction products.

Abstract: 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.

Abstract: Method is described for sequencing polypeptides by forming peptide ladders comprising a series of polypeptides in which adjacent members of the series vary by one amino acid residue and determining the identity and position of each amino acid in the polypeptide by mass spectroscopy.

Abstract: A method of increasing the sensitivity and efficiency of MALDI-MS analysis of an oligosaccharide which comprises derivatization, prior to analysis by MALDI-MS, of said oligosaccharide by efficient ligation to a basic aminooxyacetylpeptide by oxime formation reaction to result in the formation of a glycoconjugate.

Abstract: 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.

Abstract: A solid-phase method for the synthesis of N-substituted oligomers, such as poly (N-substituted glycines) (referred to herein as poly NSGs) is used to obtain oligomers, such as poly NSGs of potential therapeutic interest which poly NSGs can have a wide variety of side-chain substituents. Each N-substituted glycine monomer is assembled from two "sub-monomers" directly on the solid support. Each cycle of monomer addition consists of two steps: (1) acylation of a secondary amine bound to the support with an acylating agent comprising a leaving group capable of nucleophilic displacement by --NH.sub.2, such as a haloacetic acid, and (2) introduction of the side-chain by nucleophilic displacement of the leaving group, such as halogen (as a resin-bound .alpha.-haloacetamide) with a sufficient amount of a second sub-monomer comprising an --NH.sub.2 group, such as a primary amine, alkoxyamine, semicarbazide, acyl hydrazide, carbazate or the like.

Abstract: Disclosed herein are template assembled synthetic protein (TASP) molecules that contain dendritic linkage units having the structure .psi. (CO--S--CH.sub.2 --CO--NH). Also disclosed are methods of preparing the template assembled synthetic proteins.

Abstract: Process for the preparation of modified proteins comprising the coupling of a first peptide segment having a haloacyl group at the N-terminus thereof with a second peptide segment having a carbonylthiol group at the C-terminus thereof are disclosed. Novel modified proteins produced by the process are also disclosed.

Abstract: A solid-phase method for the synthesis of N-substituted oligomers, such as poly (N-substituted glycines) (referred to herein as poly NSGs) is used to obtain oligomers, such as poly NSGs of potential therapeutic interest which poly NSGs can have a wide variety of side-chain substituents. Each N-substituted glycine monomer is assembled from two "sub-monomers" directly on the solid support. Each cycle of monomer addition consists of two steps: (1) acylation of a secondary amine bound to the support with an acylating agent comprising a leaving group capable of nucleophilic is displacement by --NH.sub.2, such as a haloacetic acid, and (2) introduction of the side-chain by nucleophilic displacement of the leaving group, such as halogen (as a resin-bound .alpha.-haloacetamide) with a sufficient amount of a second sub-monomer comprising an --NH.sub.2 group, such as a primary amine, alkoxyamine, semicarbazide, acyl hydrazide, carbazate or the like.