Isotopically-Labeled Proteome Standards

A method for quantifying one or more biomolecules comprising:

• providing at least one sample having a biomolecule of interest to be quantified;
• providing a copy of the biomolecule of interest, the copy made or replicated using recombinant expression and said copy having at least one isotope having a mass different than that of naturally occurring isotopes of the biomolecule of interest;
• quantifying the copy biomolecule of interest;
• introducing a known quantity of the copy into the sample;
• analyzing the sample by mass spectrometry;
• and
• comparing obtained mass spectrometry peak pairs resulting from the one or more biomolecules or one or more fragments thereof, and the copy or one or more fragments thereof, to determine the quantity of the one or more biomolecules in said at least one sample.

A kit comprising at least one amino acid containing one or more atomic isotopes that are different in molecular mass from naturally-occurring isotopes;

• and one or more of:
• a culture medium for in vitro culture;
• is a template instruction for synthesizing a biomolecule standard;
• a cell lysis reagent;
• a resin for purifying said biomolecule standard;
• a protein quantitation reagent;
• an enzyme or chemical reagent capable of cleaving said biomolecule standard;
• a host cell;
• a vector;
• and
• a polymerase.

A kit comprising at least one amino acid containing one or more atomic isotopes that are different in molecular mass from naturally-occurring isotopes;

• and one or more of:
• a protein synthesis system;
• a template instruction for synthesizing a biomolecule standard;
• a resin for purifying said biomolecule standard;
• a protein quantitation reagent;
• an enzyme or chemical reagent capable of cleaving said biomolecule standard;
• a resin for purifying said biomolecule standard;
• an enzyme or chemical preparation capable of cleaving said biomolecule standard;
• a vector;
• and
• a polymerase.

A method of making an isotopically-labeled biomolecule standard comprising

• expressing a copy of a biomolecule of interest in recombinant cells cultured in media that comprises at least one isotopically-labeled precursor molecule;
• purifying said isotopically-labeled biomolecule standard;
• and
• quantitating said isotopically-labeled biomolecule standard;
• wherein the copy is enriched with at least one heavy isotope labeled molecule.

A method of making an isotopically-labeled polypeptide standard comprising

• expressing a copy of a biomolecule of interest in a protein synthesis system that comprises at least one isotopically-labeled precursor molecule;
• purifying said isotopically-labeled biomolecule standard;
• and
• quantitating said isotopically-labeled biomolecule standard;
• wherein the copy is an isotopically-labeled polypeptide standard.