Methods based on genomic and proteomic approaches are described as effective tools for the identification of microorganisms. The development of methodologies capable of differentiating, interspecifically, pathogenic, wild and genetically modified Escherichia coli strains is desirable for the fields of healthcare and Biotechnology. The purpose of this study was to verify the viability of ERIC-PCR and MALDI TOF methods in differentiating lineages of Escherichia strains. For this purpose, laboratory Escherichia coli ATCC8739, Escherichia coli W3110, Escherichia coli BL21DE3+, Escherichia coli JM109, Escherichia coli MC 1061 and Escherichia coli DH5α were subjected to ERIC-PCR and MALDI TOF mass spectrometry analyzes. Genomic (ERIC-PCR) and proteomic (MALDI-TOF) methods were able to discriminate different lineages of Escherichia coli strains including lineages of Escherichia coli K-12. However, the MALDI TOF proteomic approach revealed being able to differentiate interspecifically lineages of Escherichia coli strains. The determination of the most frequent masses found in the studied Escherichia coli strains in addition to future experiments of peptide sequencing profile and SDS-PAGE can be used as a guideline for validating a method for proteomic identification of these strains.
Key words: Escherichia coli, MALDI TOF, ERIC-PCR, proteomics and genomics