Abstract: Purified cartilage and/or bone inductive proteins and processes for producing them are disclosed. The proteins may be used in the treatment of bone and/or cartilage defects and in wound healing and related tissue repair.

Abstract: The method of the invention provides novel compounds, termed acid-labile isotope-coded extractants (ALICE), for quantitative mass spectrometric analysis of protein mixtures. The compounds contain a thiol-reactive group that is used to capture cysteine-containing peptides from all peptide mixtures, an acid-labile linker, and a non-biological polymer. One of the two acid-labile linkers is isotopically labeled and therefore enables the direct quantitation of peptides/proteins through mass spectrometric analysis. Because no functional proteins are required to capture peptides, a higher percentage of organic solvent can be used to solubilize the peptides, particularly hydrophobic peptides, through the binding, washing and eluting steps, thus permitting much better recover of peptides. Moreover, since the peptides are covalently linked to the non-biological polymer (ALICE), more stringent washing is allowed in order to completely remove non-specifically bound species.

Abstract: Arginine-containing cysteine-modifying compounds useful for MALDI-MS analysis of proteins are provided. These compounds termed isotope-coded ionization enhancement reagents (ICIER) can provide ionization enhancement in MALDI-MS, relative quantitation, and additional database searching constraints at the same time without any extra sample manipulation. More specifically, ICIER increase the ionization efficiency of cysteine-containing peptides by attachment of a guanidino functional group. ICIER also increase the overall hydrophilicity of these peptides due to the hydrophilic nature of ICIER and thus increase the percentage of recovery of these peptides during sample handling and processing such as in-gel digestion or liquid chromatography.

Abstract: The method of the invention provides novel compounds, termed acid-labile isotope-coded extractants (ALICE), for quantitative mass spectrometric analysis of protein mixtures. The compounds contain a thiol-reactive group that is used to capture cysteine-containing peptides from all peptide mixtures, an acid-labile linker, and a non-biological polymer. One of the two acid-labile linkers is isotopically labeled and therefore enables the direct quantitation of peptides/proteins through mass spectrometric analysis. Because no functional proteins are required to capture peptides, a higher percentage of organic solvent can be used to solubilize the peptides, particularly hydrophobic peptides, through the binding, washing and eluting steps, thus permitting much better recovery of peptides. Moreover, since the peptides are covalently linked to the non-biological polymer (ALICE), more stringent washing is allowed in order to completely remove non-specifically bound species.

Abstract: Arginine-containing cysteine-modifying compounds useful for MALDI-MS analysis of proteins are provided. These compounds termed isotope-coded ionization enhancement reagents (ICIER) can provide ionization enhancement in MALDI-MS, relative quantitation, and additional database searching constraints at the same time without any extra sample manipulation. More specifically, ICIER increase the ionization efficiency of cysteine-containing peptides by attachment of a guanidino functional group. ICIER also increase the overall hydrophilicity of these peptides due to the hydrophilic nature of ICIER and thus increase the percentage of recovery of these peptides during sample handling and processing such as in-gel digestion or liquid chromatography.

Abstract: The method of the invention provides novel compounds, termed acid-labile isotope-coded extractants (ALICE), for quantitative mass spectrometric analysis of protein mixtures. The compounds contain a thiol-reactive group that is used to capture cysteine-containing peptides from all peptide mixtures, an acid-labile linker, and a non-biological polymer. One of the two acid-labile linkers is isotopically labeled and therefore enables the direct quantitation of peptides/proteins through mass spectrometric analysis. Because no functional proteins are required to capture peptides, a higher percentage of organic solvent can be used to solubilize the peptides, particularly hydrophobic peptides, through the binding, washing and eluting steps, thus permitting much better recovery of peptides. Moreover, since the peptides are covalently linked to the non-biological polymer (ALICE), more stringent washing is allowed in order to completely remove non-specifically bound species.

Abstract: Purified cartilage and/or bone inductive proteins and processes for producing them are disclosed. The proteins may be used in the treatment of bone and/or cartilage defects and in wound healing and related tissue repair.