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Updated: Jun 7, 2026

Identification of Antibacterial Immunity Proteins in Escherichia coli using MALDI-TOF-TOF-MS/MS and Top-Down Proteomic Analysis
Published on: May 23, 2021
Discriminating antigen and non-antigen using proteome dissimilarity: bacterial antigens
Kamna Ramakrishnan1, Darren R Flower
1The Jenner Institute, University of Oxford, Compton, Newbury, Berkshire, United Kingdom, RG20 7NN; Medical Genetics Section,University of Edinburgh, Edinburgh, United Kingdom. EH4 2XU.
Abstract:
It has been postulated that immunogenicity results from the overall dissimilarity of pathogenic proteins versus the host proteome. We have sought to use this concept to discriminate between antigens and non-antigens of bacterial origin. Sets of 100 known antigenic and nonantigenic peptide sequences from bacteria were compared to human and mouse proteomes. Both antigenic and non-antigenic sequences lacked human or mouse homologues. Observed distributions were compared using the non-parametric Mann-Whitney test. The statistical null hypothesis was accepted, indicating that antigen and non-antigens did not differ significantly. Likewise, we were unable to determine a threshold able to separate meaningfully antigen from non-antigen. Thus, antigens cannot be predicted from pathogen genomes based solely on their dissimilarity to the human genome.
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