| abstract |
The invention provides methods for identifying polypeptides by simultaneously determining the mass of a subset of parent polypeptides from a population of polypeptides and the mass of fragments of the subset of parent polypeptides; comparing the determined masses to an annotated polypeptide index; and identifying one or more polypeptides of the annotated polypeptide index having the determined masses. The invention also provides methods for identifying a polypeptide by determining two or more characteristics associated with the polypeptide, or a fragment thereof, one of the characteristics being mass of a fragment of the polypeptide, the fragment mass being determined by mass spectrometry; comparing the characteristics associated with the polypeptide to an annotated polypeptide index; and identifying one or more polypeptides in the annotated polypeptide index having the characteristics. The method can additionally include the step of quantitating the amount of the identified polypeptide in a sample containing the polypeptide. |