Optical Whole-Genome Restriction Mapping as a Tool for Rapidly Distinguishing and Identifying Bacterial Contaminants...

Optical restriction genome mapping is a technology in which a genome is linearized on a surface and digested with specific restriction enzymes, giving an arrangement of the genome with gaps whose order and size are unique for a given organism. Current applications of this technology include assisting with the correct scaffolding and ordering of genomes in conjunction with whole-genome sequencing, observation of genetic drift and evolution using comparative genomics and epidemiological monitoring of the spread of infections. Here, we investigated the suitability of genome mapping for use in clinical labs as a potential diagnostic tool.

Using whole genome mapping, we investigated the basic performance of the technology for identifying two bacteria of interest for food-safety (Lactobacilli spp. and Enterohemorrhagic Escherichia coli). We further evaluated the performance for identifying multiple organisms from both simple and complex mixtures.

We were able to successfully generate optical restriction maps of four Lactobacillus species as well as a strain of Enterohemorrhagic Escherichia coli from within a mixed solution, each distinguished using a common compatible restriction enzyme. Finally, we demonstrated that optical restriction maps were successfully obtained and the correct organism identified within a clinical matrix.

With additional development, whole genome mapping may be a useful clinical tool for rapid invitro diagnostics.