Abstract: The invention provides methods for quantifying biomolecules, such as polypeptides in mass spectrometric analysis. The methods include use of a biomolecule standard having at least one atomic isotope different than that of the naturally occurring isotopes in the biomolecule of interest. Methods of the present invention also include methods for quantifying biomolecules where the copy biomolecule standard is made by expressing the biomolecule using a recombinant cell. Further included are the biomolecule standards themselves, method for making such standards, kits, systems, reagents, and engineered cells relating to the use of biomolecule standards in mass spectrometric analysis.

Abstract: The invention provides methods for quantifying biomolecules, such as polypeptides in mass spectrometric analysis. The methods include use of a biomolecule standard having at least one atomic isotope different than that of the naturally occurring isotopes in the biomolecule of interest. Methods of the present invention also include methods for quantifying biomolecules where the copy biomolecule standard is made by expressing the biomolecule using a recombinant cell. Further included are the biomolecule standards themselves, method for making such standards, kits, systems, reagents, and engineered cells relating to the use of biomolecule standards in mass spectrometric analysis.

Abstract: The invention provides methods for quantifying biomolecules, such as polypeptides in mass spectrometric analysis. The methods include use of a biomolecule standard having at least one atomic isotope different than that of the naturally occurring isotopes in the biomolecule of interest. Methods of the present invention also include methods for quantifying biomolecules where the copy biomolecule standard is made by expressing the biomolecule using a recombinant cell. Further included are the biomolecule standards themselves, method for making such standards, kits, systems, reagents, and engineered cells relating to the use of biomolecule standards in mass spectrometric analysis.

Abstract: The invention provides methods for quantifying biomolecules, such as polypeptides in mass spectrometric analysis. The methods include use of a biomolecule standard having at least one atomic isotope different than that of the naturally occurring isotopes in the biomolecule of interest. Methods of the present invention also include methods for quantifying biomolecules where the copy biomolecule standard is made by expressing the biomolecule using a recombinant cell. Further included are the biomolecule standards themselves, method for making such standards, kits, systems, reagents, and engineered cells relating to the use of biomolecule standards in mass spectrometric analysis.

Abstract: Methods are provided for identifying proteins that are differentially expressed in disease state and normal cells. Stable isotope labeling of cells in culture allows for the identification of a multiplicity of proteins whose differential abundance in normal and disease state cells can be indicative of the disease state. Biomarkers are identified for breast cancer, in which the biomarkers are proteins having a two-fold or greater difference in abundance between breast cancer and normal cells. Identified biomarkers can be used detection methods that can provide diagnosis, typing, staging, or prognosis of cancer, such as breast cancer, or can be used to predict the response of cancer, such as breast cancer, to one or more anti-cancer agents.

Abstract: Compositions and methods for mass spectroscopy are disclosed. The compositions and methods relate to the analysis of proteins and other biopolymers using mass spectroscopy, particularly matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS).

Abstract: The invention provides methods for quantifying biomolecules, such as polypeptides in mass spectrometric analysis. The methods include use of a biomolecule standard having at least one atomic isotope different than that of the naturally occurring isotopes in the biomolecule of interest. Methods of the present invention also include methods for quantifying biomolecules where the copy biomolecule standard is made by expressing the biomolecule using a recombinant cell. Further included are the biomolecule standards themselves, method for making such standards, kits, systems, reagents, and engineered cells relating to the use of biomolecule standards in mass spectrometric analysis.

Abstract: The invention provides methods for quantifying biomolecules, such as polypeptides in mass spectrometric analysis. The methods include use of a biomolecule standard having at least one atomic isotope different than that of the naturally occurring isotopes in the biomolecule of interest. Methods of the present invention also include methods for quantifying biomolecules where the copy biomolecule standard is made by expressing the biomolecule using a recombinant cell. Further included are the biomolecule standards themselves, method for making such standards, kits, systems, reagents, and engineered cells relating to the use of biomolecule standards in mass spectrometric analysis.

Abstract: Compositions and methods for mass spectroscopy are disclosed. The compositions and methods relate to the analysis of proteins and other biopolymers using mass spectroscopy, particularly matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS).

Abstract: Methods are provided for identifying proteins that are differentially expressed in disease state and normal cells. Stable isotope labeling of cells in culture allows for the identification of a multiplicity of proteins whose differential abundance in normal and disease state cells can be indicative of the disease state. Biomarkers are identified for breast cancer, in which the biomarkers are proteins having a two-fold or greater difference in abundance between breast cancer and normal cells. Identified biomarkers can be used detection methods that can provide diagnosis, typing, staging, or prognosis of cancer, such as breast cancer, or can be used to predict the response of cancer, such as breast cancer, to one or more anti-cancer agents.

Abstract: Methods are provided for identifying proteins that are differentially expressed in disease state and normal cells. Stable isotope labeling of cells in culture allows for the identification of a multiplicity of proteins whose differential abundance in normal and disease state cells can be indicative of the disease state. Biomarkers are identified for breast cancer, in which the biomarkers are proteins having a two-fold or greater difference in abundance between breast cancer and normal cells. Identified biomarkers can be used detection methods that can provide diagnosis, typing, staging, or prognosis of cancer, such as breast cancer, or can be used to predict the response of cancer, such as breast cancer, to one or more anti-cancer agents.

Abstract: The invention provides methods for quantifying biomolecules, such as polypeptides in mass spectrometric analysis. The methods include use of a biomolecule standard having at least one atomic isotope different than that of the naturally occurring isotopes in the biomolecule of interest. Methods of the present invention also include methods for quantifying biomolecules where the copy biomolecule standard is made by expressing the biomolecule using a recombinant cell. Further included are the biomolecule standards themselves, method for making such standards, kits, systems, reagents, and engineered cells relating to the use of biomolecule standards in mass spectrometric analysis.

Abstract: Compositions and methods for mass spectroscopy are disclosed. The compositions and methods relate to the analysis of proteins and other biopolymers using mass spectroscopy, particularly matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS).

Abstract: The invention provides compositions, kits, and methods for calibrating a mass spectrometer using two or more recombinant proteins and one or more energy-absorbing molecules. The recombinant proteins of the invention display high purities, making them suitable for use in mass spectrometry.