The introduction of MALDI TOF mass spectrometry (MALDI TOF MS) in clinical microbiology at the end of 2010 has been a revolution for microbial identification [1]. Unlike the conventional uses of MALDI TOF MS in clinical chemistry laboratories, detecting and quantifying specific peaks of known proteins, the routine use of MALDI TOF MS in clinical microbiology is based on the comparison of mass spectra (intensity of m/z values corresponding to peptides in the low m/z region) to a database of mass spectra, allowing the attribution of matching scores without any a priori on the corresponding proteins.