Microbial Identification and Quantitation Using MS Cleavable Tags

Abstract

Systems and methods are provided for microbial identification using cleavable tags. Control information is sent to a mass spectrometer to fragment one or more nucleic acid primers labeled with a first tag and monitor for an intensity of the first tag in a mass spectrometry (MS) method. An ion source provides a beam of ions from a polymerase chain reaction amplified sample that includes one or more nucleic acid primers labeled with the first tag. The first tag binds to one or more nucleic acid primers of a known microbe and is cleaved from the nucleic acid primers during the MS method. The mass spectrometer receives the beam of ions and is adapted to perform the MS method on the beam of ions. If the intensity of the first tag received from the mass spectrometer exceeds a threshold value, the known microbe is identified in the sample.

What is claimed is: 
     
         1 . A system for microbial identification using cleavable tags that bind to nucleic acids, comprising:
 an ion source that provides a beam of ions from a polymerase chain reaction (PCR) amplified sample that includes one or more nucleic acid primers labeled with a first tag that binds to one or more nucleic acid primers of a known microbe and is cleaved from the one or more nucleic acid primers of the known microbe during mass spectrometry;   a mass spectrometer that receives the beam of ions and is adapted to perform a mass spectrometry (MS) method on the beam of ions; and   a processor in communication with the mass spectrometer and the ion source that   sends control information to the mass spectrometer to fragment the labeled one or more nucleic acid primers and monitor for an intensity of the first tag in the MS method, and   if the intensity of the first tag received from the mass spectrometer exceeds a threshold value, identifies the known microbe in the sample, wherein the first tag includes two or more copies of a mass spectrometry enhancing group that increase the intensity of the mass spectrometry enhancing group two or more times when the labeled nucleic acid primer is fragmented to increase a signal intensity and lower a detection limit of the known microbe, wherein the mass spectrometer monitors for the mass spectrometry enhancing group, and wherein the intensity of the first tag is an intensity of the mass spectrometry enhancing group.