Abstract: The present invention provides engineered proteins and biomedical products made from the engineered proteins. The biomedical products include lenses useful for ophthalmic purposes.

Abstract: Methods for producing modified polypeptides containing amino acid analogues are disclosed, as well as compositions comprising purified dihydrofolate reductase polypeptides, produced by the methods of the invention. In certain aspects, methionine residues of the compositions are replaced with homoallyglycine, homoproparglycine, norvaline, norleucine, cis-crotyiglycine, trans-crotylglycine, 2-aminoheptanoic acid, 2-butynyiglycine and allyglycine.

Abstract: The instant invention provides methods, reagents, and computational tools for designing non-natural substrate analogs for enzymes, especially for designing unnatural amino acid analogs for aminoacyl tRNA Synthetases (AARSs), such as the Phe tRNA Synthetase. The instant invention also provides methods to incorporate unnatural amino acid analogs, especially those with interesting functional groups, into protein products to generate proteins of modified or novel functions.

Abstract: The invention provides methods, reagents and systems for incorporating non-natural amino acids into proteins, preferably in vivo, using the endogenous protein synthesis machinery of an organism. The incorporated non-natural amino acids contain reactive groups for further chemical reagents, which may serve as a “handle” to enrich the proteins or fragments thereof in a number of uses, such as proteomic analysis, imaging of diseased tissues/cells, etc.

Abstract: The instant invention provides methods, reagents, and computational tools for designing non-natural substrate analogs for enzymes, especially for designing unnatural amino acid analogs for aminoacyl tRNA Synthetases (AARSs), such as the Phe tRNA Synthetase. The instant invention also provides methods to incorporate unnatural amino acid analogs, especially those with interesting functional groups, into protein products to generate proteins of modified or novel functions.

Abstract: The present invention relates generally to the amphiphilic polyelectrolyte, poly(2-ethylacrylic acid) and covalently bonded lipids to generate Lipo-PEAA. These Lipo-PEAA are then used to make pH-sensitive liposomes which become unstable, permeable or fusogenic with certain pH changes. In addition, this invention generally describes methods for delivering therapeutic compounds and drugs to target cells by administering to a host the pH-sensitive liposomes of the present invention.

Abstract: The invention provides a method of incorporating nonstandard amino acids into a protein by utilizing a modified aminoacyl-tRNA synthetase to charge the nonstandard amino acid to a modified tRNA, which forms strict Watson-Crick base-pairing with a codon that normally forms wobble base-pairing with natural tRNAs.

Abstract: The invention provides methods, systems and reagents for regulating pH-sensitive protein interaction by incorporating non-natural amino acids into the protein (e.g. an antibody, or its functional fragment, derivative, etc.). The invention also relates to specific uses in regulating pH-sensitive binding of antibodies to tumor site, by conferring enhanced tumor-specificity/selectivity. In that embodiment, the non-natural amino acids preferably have desirable side-chain pKa's, such that at below physiological pH (e.g. about pH 6.3-6.5) the non-natural amino acid confer enhanced binding to tumor antigens in acidic environments. Such non-natural amino acids can be incorporated by any suitable means, such as by utilizing a modified aminoacyl-tRNA synthetase to charge the nonstandard amino acid to a modified tRNA, which forms strict Watson-Crick base-pairing with a codon that normally forms wobble base-pairing with natural tRNAs (e.g. the degenerate codon orthogonal system.

Abstract: The present invention provides engineered proteins and biomedical products made from the engineered proteins. The biomedical products include lenses useful for ophthalmic purposes.

Abstract: Compositions and methods for transport or release of therapeutic and diagnostic agents or metabolites or other analytes from cells, compartments within cells, or through cell layers or barriers are described. The compositions include a membrane barrier transport enhancing agent and are usually administered in combination with an enhancer and/or exposure to stimuli to effect disruption or altered permeability, transport or release. In a preferred embodiment, the compositions include compounds which disrupt endosomal membranes in response to the low pH in the endosomes but which are relatively inactive toward cell membranes, coupled directly or indirectly to a therapeutic or diagnostic agent. Other disruptive agents can also be used, responsive to stimuli and/or enhancers other than pH, such as light, electrical stimuli, electromagnetic stimuli, ultrasound, temperature, or combinations thereof.

Abstract: The invention provides methods of identifying one or more nucleic acids in a sample. The nucleic acids, for example, expressed genes in a cell, can be identified by contacting the nucleic acids with oligonucleotides having detector tags, and selector tags to form tagged oligonucleotides. Each nucleic acid can be uniquely identified by mass-spectrophotometric analysis of the detector tag.

Abstract: The present invention provides a method for producing modified stable polypeptides introducing at least one non-natural amino acid into the hydrophobic region of the polypeptide. The thermal and chemical stability of such polypeptides is improved compared to those properties of its corresponding wild type proteins.

Abstract: Methods for producing modified polypeptides containing amino acid analogues are disclosed.

Abstract: The instant invention provides methods, reagents, and computational tools for designing non-natural substrate analogs for enzymes, especially for designing unnatural amino acid analogs for aminoacyl tRNA Synthetases (AARSs), such as the Phe tRNA Synthetase. The instant invention also provides methods to incorporate unnatural amino acid analogs, especially those with interesting functional groups, into protein products to generate proteins of modified or novel functions.

Abstract: A composition that expands or contracts upon a change in exposure to light energy is provided that comprises a protein or protein-based polymeric material having an inverse temperature transition in the range of liquid water, wherein at least a fraction of the monomers in the polymer contain an light energy-responsive group that undergoes a change in hydrophobicity or polarity upon a change in exposure to light energy and is present in an amount sufficient to provide a shift in the inverse temperature transition of the polymer upon the change in exposure to light energy. Compositions of the invention, including those further containing a side-chain chemical couple, can be used in a variety of different applications to produce mechanical work, cause turbidity changes, cause chemical changes in an enclosed environment, or transduce other free energies by varying the exposure to light energy on the composition.

Abstract: Methods for producing modified polypeptides containing amino acid analogues are disclosed. The invention further provides purified dihydrofolate reductase polypeptides, produced by the methods of the invention, in which the methionine residues have been replaced with homoallyglycine, homoproparglycine, norvaline, norleucine, cis-crotylglycine, trans-crotylglycine, 2-aminoheptanoic acid, 2-butynylglycine and allylglycine.

Abstract: The invention provides methods of identifying one or more nucleic acids in a sample. The nucleic acids, for example, expressed genes in a cell, can be identified by contacting the nucleic acids with oligonucleotides having detector tags, and selector tags to form tagged oligonucleotides. Each nucleic acid can be uniquely identified by mass-spectrophotometric analysis of the detector tag.

Abstract: Methods for producing modified polypeptides containing amino acid analogues are disclosed. The invention further provides purified dihydrofolate reductase polypeptides, produced by the methods of the invention, in which the methionine residues have been replaced with homoallyglycine, homoproparglycine, norvaline, norleucine, cis-crotylglycine, trans-crotylglycine, 2-aminoheptanoic acid, 2-butynylglycine and allylglycine.

Abstract: Compositions and methods for transport or release of therapeutic and diagnostic agents or metabolites or other analytes from cells, compartments within cells, or through cell layers or barriers are described. The compositions include a membrane barrier transport enhancing agent and are usually administered in combination with an enhancer and/or exposure to stimuli to effect disruption or altered permeability, transport or release. In a preferred embodiment, the compositions include compounds which disrupt endosomal membranes in response to the low pH in the endosomes but which are relatively inactive toward cell membranes, coupled directly or indirectly to a therapeutic or diagnostic agent. Other disruptive agents can also be used, responsive to stimuli and/or enhancers other than pH, such as light, electrical stimuli, electromagnetic stimuli, ultrasound, temperature, or combinations thereof.

Abstract: The invention is based on the discovery that a block copolymer that includes .alpha.-helical blocks, e.g., terminal blocks, which form intermolecular coiled-coil structures, and one or more random-coil blocks, which link the .alpha.-helical blocks, can form suspensions that can reversibly gel to form monodisperse hydrogels. The transition between the gel and liquid phases depends on pH, temperature, concentration, and chemical structure. The copolymers can be synthesized biologically through genetic engineering.