Methods for detection and identification of pathogenic bacteria

Abstract

Scope and Method of Study:

1. Identification of unique genomic sequences associated with low versus high cytotoxicity isolates of Clostridium piliforme.;

2. Develop an amplified fluorescent antigen displacement assay directed toward methicillin-resistant Staphylococcus aureus low affinity penicillin binding protein PBP2a.;

3. Develop a label-free multiplex assay for specific detection of enteric pathogens Salmonella typhimurium and E. coli O157:H7 using optical microring resonators.

Findings and Conclusions:

1. Markers specific for high cytotoxicity C. piliforme isolate were not identified. However, 16 possible and 1 confirmed C. piliforme-specific marker were identified.;

2. Amplified fluorescent peptide displacement assay component was developed, intended as part of a flow-through detection platform. Some detection of antigen (labeled peptide) was detected in assay when applied to Amplifying Fluorescent Polymer (AFP), but results were not strongly positive, possibly due to poor performing peptide antigen-derived antibody.

3. Label-free detection of whole bacterial cells was clearly demonstrated with concentrations as low as 10e5 CFU/ml. Whole cell detection on microring arrays was performed in a sequential binding assay to demonstrate multiplex capability with good success.