Despite the great promise for the field of proteomics, technologies for identifying and quantifying low abundance proteins remain limited. Mass spectrometry (MS) is the most widely used approach for peptide/protein identification and quantification, and has been the method of choice for clinical biomarker discovery. Although MS technology has rapidly advanced, the detection of current commercial instruments are limited in a dynamic range of 10⁴ ~ 10⁵ even when combined with good sample separation. These represent a significant drawback when applied to the analysis of complex biological samples, such as serum or cell lysates where the proteome can span a dynamic range of ~10¹⁰ and most valuable protein biomarkers are believed to be in low abundance (i.e., concentrations of a pmol/L or less). To address this technological bottleneck, we are developing a new technology platform--next gen protein sequencing--based on large-scale, massively parallel, single-molecule peptide sequencing. This platform is not limited in dynamic range and thus will enable identification of the composition of complete proteomes through the individual sequencing of billions of peptides, including those of low abundance. The method will also enable absolute protein quantification by digitally counting the number of peptides with the same sequence, similar to digital polymerase chain reaction (PCR).

 

key words

Protein; Single-molecule; Sequencing; Proteomics; Microfluidics; Fluorescence; Biochemistry; High-throughput;

Citizenship:  Open to U.S. citizens

Level:  Open to Postdoctoral applicants