Performance evaluation of endopeptidase Lys-C spin column rapid digestion compared to traditional in-solution endopeptidase Lys-C digestion

摘要

The performance of the prototype endopeptidase Lys-C spin column was favorable compared to the traditional overnight in-solution endopeptidase Lys-C digestion based on the total number of unique peptide identifications as well as their average charge state and average peptide length. The number of unique peptide identifications obtained from the analysis of the endopeptidase Lys-C spin column sample ranged from 70-92percent of that obtained from the analysis of the in-solution endopeptidase Lys-C digestion (Figure 2). These numbers are within the range expected for spin column systems due to incomplete elution of peptides off the column. Improvement in total unique peptide identifications may be assisted by performing multiple elutions. Analysis of a second elution from the Lys-C spin column yielded additional unique peptide identifications ranging from 33-72percent relative to the first elution (Figure 2). Comparison of the datasets from each elution showed that the second elution contained peptides from proteins not identified in the first elution.